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Haug D, Schreiter R, Thesing B, Rathmann L, Lambertz C, Hofmann P, Erhard M, Bellof G, Schmidt E. Injurious pecking in organic turkey fattening-effects of husbandry and feeding on injuries and plumage damage of a slow- (Auburn) and a fast-growing (B.U.T.6) genotype. Poult Sci 2023; 102:102746. [PMID: 37327745 PMCID: PMC10404662 DOI: 10.1016/j.psj.2023.102746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 06/18/2023] Open
Abstract
Injuries and plumage damage (PD) are important indicators of welfare. First priority in turkey fattening is to reduce injurious pecking, which includes aggressive pecking (agonistic behavior) and additionally severe feather pecking (SFP) and cannibalism with their multifactorial reasons. Still, there are few studies available evaluating different genotypes for their welfare status under organic conditions. The aim of this study was to investigate the effects of genotype and husbandry with 100% organic feeding (2 variants with different riboflavin content: V1 and V2) on injuries and PD. During rearing nonbeaktrimmed male turkeys of a slow- (Auburn, n = 256) and fast-growing (B.U.T.6, n = 128) genotype were kept in 2 indoor housing systems (without environmental enrichment (EE) = H1-, n = 144 and with EE = H2+, n = 240). During fattening 13 animals per pen of H2+ were relocated to a free-range system (H3 MS, n = 104). EE included pecking stones, elevated seating platforms and silage feeding. The study included five 4-wk feeding phases. At the end of each phase, injuries and PD were scored to assess animal welfare. Injury scores ranged from 0 (=no damage) to 3 (=severe damage) and PD from 0 to 4. Injurious pecking was observed from the 8th week onward (injuries: 16.5% and PD: 31.4%). Binary logistic regression models showed that both indicators were affected by genotype (each P < 0.001), husbandry (each P < 0.001), feeding (injuries P = 0.004; PD P = 0.003), and age (each P < 0.001). Auburn showed less injuries and PD than B.U.T.6. H1- had the fewest injuries and PD for Auburn animals compared to H2+ or H3 MS. In summary, the use of alternative genotypes (Auburn) in organic fattening improved welfare, but keeping them in free-range systems or in husbandry with EE, does not lead to a reduction of injurious pecking. Therefore, further studies are needed with more and changing enrichment materials, further management measures, changes in housing structure, and even more intensive animal care.
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Affiliation(s)
- D Haug
- Weihenstephan-Triesdorf University of Applied Sciences, 85354 Freising, Germany.
| | - R Schreiter
- Centre for Applied Research and Technology e.V. at the Dresden University of Applied Sciences, 01069 Dresden, Germany
| | - B Thesing
- Weihenstephan-Triesdorf University of Applied Sciences, 85354 Freising, Germany
| | - L Rathmann
- Bavarian State Estates, Kitzingen, Germany
| | - C Lambertz
- Research Institute of Organic Agriculture (FiBL), 37213 Witzenhausen, Germany
| | - P Hofmann
- Bavarian State Research Center for Agriculture, Kitzingen, Germany
| | - M Erhard
- Chair of Animal Welfare, Ethology, Animal Hygiene and Animal Husbandry, Department of Veterinary Sciences, LMU Munich, 80539 Munich, Germany
| | - G Bellof
- Weihenstephan-Triesdorf University of Applied Sciences, 85354 Freising, Germany
| | - E Schmidt
- Weihenstephan-Triesdorf University of Applied Sciences, 85354 Freising, Germany
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Bink DI, Pham TP, Van Bergen A, Stanicek L, Van Der Ven D, Groenen EMJ, Kaagman L, Jonk M, Hofmann P, Dimmeler S, Boon RA. Long non-coding RNA TERRA regulates DNA damage and survival of endothelial cells and cardiomyocytes: implications for aging. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.3018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Ageing is the major risk factor for cardiovascular disease. Long non-coding RNAs are emerging as novel regulators of cellular functions and contributors to cardiovascular ageing. One of the hallmarks of aging is telomere attrition. Non-coding transcripts called Telomeric repeat-containing RNA (TERRA) are molecules of 0.2–10kb in length which are transcribed from the subtelomeres and telomeres of chromosomes and might play a role in cardiovascular ageing.
Purpose
This study aims to characterize the role of TERRA in aging of the cardiovascular system.
Methods and results
TERRA molecules from different chromosomes were upregulated in the hearts of old mice compared to young mice (p=0.002). Increased TERRA expression was also shown in heart tissue of patients with ischemic heart disease compared to donors (p=0.001). In vitro an upregulation of the TERRA molecule transcribed from chromosome 20 (h20q-TERRA) was found with increasing passage in human umbilical vein endothelial cells (HUVECs) (p=0.014) and IPSC-derived cardiomyocytes (p=0.011). After h20q-TERRA knockdown with LNA GapmeRs, HUVECs show less sprout formation in a spheroid assay compared to negative control transfected HUVECs (p=0.002), without showing a change in migration (p=0.205) or proliferation (p=0.114). H20q-TERRA knockdown revealed an increase in apoptosis (p=0.015) and telomeric DNA damage (p=0.011) and a decrease in telomere length (p<0.001), while lentiviral TERRA-repeat overexpression had the opposite effect (p=0.016, p=0.031, p<0.001, resp.). Apoptosis (p=0.012) and telomeric DNA damage (p=0.007) were also increased after the knockdown of h20q-TERRA in human cardiomyocytes. An apoptosis pathway profiler array in HUVECs showed that the expression of the antioxidant PON2 was decreased after knockdown of h20q-TERRA (p=0.040). PON2 expression was increased after TERRA overexpression (p=0.003). RNA immunoprecipitation revealed that TERRA can bind to PON2. Silencing PON2 in TERRA overexpressing cells diminished the TERRA-mediated decrease in caspase activation, suggesting a detrimental role for PON2 in caspase activation and endothelial cell survival.
Conclusion
Our data demonstrates that TERRA is upregulated with ageing and plays a role in endothelial and cardiomyocyte function and survival.
Funding Acknowledgement
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020
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Affiliation(s)
- D I Bink
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - T P Pham
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - A Van Bergen
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - L Stanicek
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - D Van Der Ven
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - E M J Groenen
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - L Kaagman
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - M Jonk
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
| | - P Hofmann
- Johann Wolfgang Goethe University, Institute for Cardiovascular Regeneration , Frankfurt am Main , Germany
| | - S Dimmeler
- Johann Wolfgang Goethe University, Institute for Cardiovascular Regeneration , Frankfurt am Main , Germany
| | - R A Boon
- Amsterdam UMC - Location VUmc , Amsterdam , The Netherlands
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Hofmann P, Hagen S, Noack V, Noack V, Schanz G, Schumacher G, Sepold L. Essential experimental results of the CORA test program on severe core damage phenomena / Wesentliche experimentelle Ergebnisse des Versuchsprogramms CORA zu Phänomenen bei schwerer Corezerstörung. KERNTECHNIK 2021. [DOI: 10.1515/kern-1994-594-515] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Afroundeh R, Hofmann P, Esmaeilzadeh S, Narimani M, Pesola AJ. Agreement between heart rate deflection point and maximal lactate steady state in young adults with different body masses. Physiol Int 2021. [PMID: 33764893 DOI: 10.1556/2060.2021.00004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/20/2020] [Indexed: 11/19/2022]
Abstract
We examined the agreement between heart rate deflection point (HRDP) variables with maximal lactate steady state (MLSS) in a sample of young males categorized to different body mass statuses using body mass index (BMI) cut-off points. One hundred and eighteen young males (19.9 ± 4.4 years) underwent a standard running incremental protocol with individualized speed increment between 0.3 and 1.0 km/h for HRDP determination. HRDP was determined using the modified Dmax method called S.Dmax. MLSS was determined using 2-5 series of constant-speed treadmill runs. Heart rate (HR) and blood lactate concentration (La) were measured in all tests. MLSS was defined as the maximal running speed yielding a La increase of less than 1 mmol/L during the last 20 min. Good agreement was observed between HRDP and MLSS for HR for all participants (±1.96; 95% CI = -11.5 to +9.2 b/min, ICC = 0.88; P < 0.001). Good agreement was observed between HRDP and MLSS for speed for all participants (±1.96; 95% CI = -0.40 to +0.42 km/h, ICC = 0.98; P < 0.001). The same findings were observed when participants were categorized in different body mass groups. In conclusion, HRDP can be used as a simple, non-invasive and time-efficient method to objectively determine submaximal aerobic performance in nonathletic young adult men with varying body mass status, according to the chosen standards for HRDP determination.
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Affiliation(s)
- R Afroundeh
- 1Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, Islamic Republic of Iran
| | - P Hofmann
- 2Exercise Physiology, Training & Training Therapy Research Group; Institute of Human Movement Science, Sport & Health; University of Graz, Austria
| | - S Esmaeilzadeh
- 1Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, Islamic Republic of Iran
- 3Active Life Lab, South-Eastern Finland University of Applied Sciences, Mikkeli, Finland
| | - M Narimani
- 1Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, Ardabil, Islamic Republic of Iran
| | - A J Pesola
- 3Active Life Lab, South-Eastern Finland University of Applied Sciences, Mikkeli, Finland
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Abstract
Abstract
Ageing is the major risk factor for cardiovascular disease. Current therapies are mainly based on proteins, while targeting long non-coding RNAs (lncRNAs) is largely unexplored. Long non-coding RNAs are emerging as novel regulators of cellular functions and contributors to cardiovascular ageing. Although telomeres are heterochromatic regions, non-coding transcripts called Telomeric repeat-containing RNA (TERRA) are transcribed from the telomeres of most chromosomes. The transcription of TERRA starts at the subtelomere and ends in the telomere, leading to molecules of 0.2–10kb. This study aims to characterize the role of TERRA in the cardiovascular system.
TERRA molecules from different chromosomes were upregulated in the hearts of old mice compared to young mice (p=0.002). An increased TERRA expression was also shown in heart tissue of patients with ischemic heart disease compared to donor heart tissue (p=0.001). In vitro an upregulation of the TERRA molecule transcribed from chromosome 20 (h20q-TERRA) was found in old passage human umbilical vein endothelial cells (HUVECs) (P15–17) compared to young HUVECs (P3) (p=0.014). IPSC-derived cardiomyocytes also increased the expression of h20q-TERRA with increasing passage (p=0.011). After knockdown of h20q-TERRA with LNA GapmeRs HUVECs show less sprout formation in a spheroid assay compared to negative control transfected HUVECs (p=0.002), without showing a change in migration (p=0.205) or proliferation (p=0.114). H20q-TERRA knockdown revealed that there was more apoptosis (p=0.015), more DNA damage as measured with the comet assay (p<0.001), increased γH2AX levels (p=0.029) and an increase in γH2AX colocalization with the telomere (p=0.011). The amount of phosphorylated P53 was also increased after knockdown (p=0.038), while it was decreased after TERRA overexpression (p=0.001). Inhibition of the ATM-yH2AX-P53 pathway did however not reduce the increased apoptosis after knockdown (KU60019 p=0.399; siP53 p=0.303). Silencing the m18-TERRA molecule in mouse endothelial H5V cells led to an increase in caspase activity (p=0.004) similar to what was shown in HUVECs. In addition, increased caspase activity (p=0.012), increased γH2AX levels (p<0.001) and increased γH2AX colocalization with the telomere (p=0.007) was also shown after silencing of h20q-TERRA in human cardiomyocytes.
In summary, our data demonstrates that TERRA is upregulated with ageing and plays a role in endothelial and cardiomyocyte function and survival. These data show that TERRA transcripts are induced in cardiovascular ageing and are essential for endothelial cell function.
Funding Acknowledgement
Type of funding source: Public grant(s) – EU funding. Main funding source(s): Horizon 2020
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Affiliation(s)
- D Bink
- Amsterdam UMC - Location VUmc, Amsterdam, Netherlands (The)
| | - T.P Pham
- Amsterdam UMC - Location VUmc, Amsterdam, Netherlands (The)
| | - P Hofmann
- Amsterdam UMC - Location VUmc, Amsterdam, Netherlands (The)
| | - S Dimmeler
- Johann Wolfgang Goethe University, Institute for Cardiovascular Regeneration, Frankfurt am Main, Germany
| | - R.A Boon
- Johann Wolfgang Goethe University, Institute for Cardiovascular Regeneration, Frankfurt am Main, Germany
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6
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Hütter C, Lanner M, Aigmüller T, Simon K, Hofmann P, Kratky M, Engelmann G, Mutz-Eckhart C, Blatt-Gunegger M, Klammer S, Berger G, Bermann C, Resetarits K, Huber A, Lang P, Lessiak V, Tamussino K. Implementierung der prophylaktischen bilateralen Salpingektomie (PBS) bei der minimal-invasiven Hysterektomie. Geburtshilfe Frauenheilkd 2020. [DOI: 10.1055/s-0040-1713204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
- C Hütter
- Universitätsklinik für Frauenheilkunde und Geburtshilfe der Med. Universität Graz
| | - M Lanner
- Universitätsklinik für Frauenheilkunde und Geburtshilfe der Med. Universität Graz
| | | | - K Simon
- LKH Hochsteiermark, Standort Leoben
| | - P Hofmann
- LKH Weststeiermark, Standort Deutschlandsberg
| | - M Kratky
- LKH Weststeiermark, Standort Deutschlandsberg
| | - G Engelmann
- LKH Murtal, Standort Judenburg
- LKH Rottenmann
| | | | | | | | | | | | | | | | - P Lang
- Krankenhaus der Barmherzigen Brüder Graz
| | - V Lessiak
- Krankenhaus der Barmherzigen Brüder Graz
| | - K Tamussino
- Universitätsklinik für Frauenheilkunde und Geburtshilfe der Med. Universität Graz
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7
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Hütter C, Lanner M, Aigmüller T, Simon K, Hofmann P, Kratky M, Engelmann G, Mutz-Eckhart C, Blatt-Gunegger M, Klammer S, Berger G, Bermann C, Resetarits K, Huber A, Lang P, Lessiak V, Tamussino K. Implementierung der prophylaktischen bilateralen Salpingektomie (PBS) bei der minimal-invasiven Hysterektomie. Geburtshilfe Frauenheilkd 2020. [DOI: 10.1055/s-0039-3403389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
- C Hütter
- Universitätsklinik für Frauenheilkunde und Geburtshilfe der Med. Universität Graz
| | - M Lanner
- Universitätsklinik für Frauenheilkunde und Geburtshilfe der Med. Universität Graz
| | | | - K Simon
- LKH Hochsteiermark, Standort Leoben
| | - P Hofmann
- LKH Weststeiermark, Standort Deutschlandsberg
| | - M Kratky
- LKH Weststeiermark, Standort Deutschlandsberg
| | | | | | | | | | | | | | | | | | - P Lang
- Krankenhaus der Barmherzigen Brüder Graz
| | - V Lessiak
- Krankenhaus der Barmherzigen Brüder Graz
| | - K Tamussino
- Universitätsklinik für Frauenheilkunde und Geburtshilfe der Med. Universität Graz
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8
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Pakpour-Tabrizi AC, Schenk AK, Holt AJU, Mahatha SK, Arnold F, Bianchi M, Jackman RB, Butler JE, Vikharev A, Miwa JA, Hofmann P, Cooil SP, Wells JW, Mazzola F. The occupied electronic structure of ultrathin boron doped diamond. Nanoscale Adv 2020; 2:1358-1364. [PMID: 36133056 PMCID: PMC9417656 DOI: 10.1039/c9na00593e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 01/27/2020] [Indexed: 06/13/2023]
Abstract
Using angle-resolved photoelectron spectroscopy, we compare the electronic band structure of an ultrathin (1.8 nm) δ-layer of boron-doped diamond with a bulk-like boron doped diamond film (3 μm). Surprisingly, the measurements indicate that except for a small change in the effective mass, there is no significant difference between the electronic structure of these samples, irrespective of their physical dimensionality, except for a small modification of the effective mass. While this suggests that, at the current time, it is not possible to fabricate boron-doped diamond structures with quantum properties, it also means that nanoscale boron doped diamond structures can be fabricated which retain the classical electronic properties of bulk-doped diamond, without a need to consider the influence of quantum confinement.
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Affiliation(s)
- A C Pakpour-Tabrizi
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London 17-19 Gordon Street London WC1H 0AH UK
| | - A K Schenk
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology NO-7491 Trondheim Norway
| | - A J U Holt
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University 8000 Aarhus C Denmark
| | - S K Mahatha
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University 8000 Aarhus C Denmark
| | - F Arnold
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University 8000 Aarhus C Denmark
| | - M Bianchi
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University 8000 Aarhus C Denmark
| | - R B Jackman
- London Centre for Nanotechnology, Department of Electronic and Electrical Engineering, University College London 17-19 Gordon Street London WC1H 0AH UK
| | - J E Butler
- Cubic Carbon Ceramics 855 Carson Road Huntingtown MD 20639 USA
| | - A Vikharev
- Institute of Applied Physics, Russian Academy of Sciences 46 Ul'yanov Street Nizhny Novgorod 603950 Russia
| | - J A Miwa
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University 8000 Aarhus C Denmark
| | - P Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University 8000 Aarhus C Denmark
| | - S P Cooil
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology NO-7491 Trondheim Norway
- Department of Physics, Aberystwyth University Aberystwyth SY23 3BZ UK
| | - J W Wells
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology NO-7491 Trondheim Norway
| | - F Mazzola
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology NO-7491 Trondheim Norway
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Kutnyakhov D, Xian RP, Dendzik M, Heber M, Pressacco F, Agustsson SY, Wenthaus L, Meyer H, Gieschen S, Mercurio G, Benz A, Bühlman K, Däster S, Gort R, Curcio D, Volckaert K, Bianchi M, Sanders C, Miwa JA, Ulstrup S, Oelsner A, Tusche C, Chen YJ, Vasilyev D, Medjanik K, Brenner G, Dziarzhytski S, Redlin H, Manschwetus B, Dong S, Hauer J, Rettig L, Diekmann F, Rossnagel K, Demsar J, Elmers HJ, Hofmann P, Ernstorfer R, Schönhense G, Acremann Y, Wurth W. Time- and momentum-resolved photoemission studies using time-of-flight momentum microscopy at a free-electron laser. Rev Sci Instrum 2020; 91:013109. [PMID: 32012554 DOI: 10.1063/1.5118777] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 11/30/2019] [Indexed: 06/10/2023]
Abstract
Time-resolved photoemission with ultrafast pump and probe pulses is an emerging technique with wide application potential. Real-time recording of nonequilibrium electronic processes, transient states in chemical reactions, or the interplay of electronic and structural dynamics offers fascinating opportunities for future research. Combining valence-band and core-level spectroscopy with photoelectron diffraction for electronic, chemical, and structural analyses requires few 10 fs soft X-ray pulses with some 10 meV spectral resolution, which are currently available at high repetition rate free-electron lasers. We have constructed and optimized a versatile setup commissioned at FLASH/PG2 that combines free-electron laser capabilities together with a multidimensional recording scheme for photoemission studies. We use a full-field imaging momentum microscope with time-of-flight energy recording as the detector for mapping of 3D band structures in (kx, ky, E) parameter space with unprecedented efficiency. Our instrument can image full surface Brillouin zones with up to 7 Å-1 diameter in a binding-energy range of several eV, resolving about 2.5 × 105 data voxels simultaneously. Using the ultrafast excited state dynamics in the van der Waals semiconductor WSe2 measured at photon energies of 36.5 eV and 109.5 eV, we demonstrate an experimental energy resolution of 130 meV, a momentum resolution of 0.06 Å-1, and a system response function of 150 fs.
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Affiliation(s)
- D Kutnyakhov
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - R P Xian
- Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - M Dendzik
- Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - M Heber
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - F Pressacco
- Physics Department and Centre for Free-Electron Laser Science (CFEL), University of Hamburg, 22761 Hamburg, Germany
| | - S Y Agustsson
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - L Wenthaus
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - H Meyer
- Physics Department and Centre for Free-Electron Laser Science (CFEL), University of Hamburg, 22761 Hamburg, Germany
| | - S Gieschen
- Physics Department and Centre for Free-Electron Laser Science (CFEL), University of Hamburg, 22761 Hamburg, Germany
| | - G Mercurio
- Physics Department and Centre for Free-Electron Laser Science (CFEL), University of Hamburg, 22761 Hamburg, Germany
| | - A Benz
- Physics Department and Centre for Free-Electron Laser Science (CFEL), University of Hamburg, 22761 Hamburg, Germany
| | - K Bühlman
- Laboratorium für Festkörperphysik, ETH Zürich, 8093 Zürich, Switzerland
| | - S Däster
- Laboratorium für Festkörperphysik, ETH Zürich, 8093 Zürich, Switzerland
| | - R Gort
- Laboratorium für Festkörperphysik, ETH Zürich, 8093 Zürich, Switzerland
| | - D Curcio
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | - K Volckaert
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | - M Bianchi
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | - Ch Sanders
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell OX11 0QX, United Kingdom
| | - J A Miwa
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | - S Ulstrup
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | - A Oelsner
- Surface Concept GmbH, 55124 Mainz, Germany
| | - C Tusche
- Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-6), 52428 Jülich, Germany
| | - Y-J Chen
- Forschungszentrum Jülich GmbH, Peter Grünberg Institut (PGI-6), 52428 Jülich, Germany
| | - D Vasilyev
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - K Medjanik
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - G Brenner
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - S Dziarzhytski
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - H Redlin
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - B Manschwetus
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - S Dong
- Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - J Hauer
- Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - L Rettig
- Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - F Diekmann
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - K Rossnagel
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - J Demsar
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - H-J Elmers
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - Ph Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
| | - R Ernstorfer
- Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - G Schönhense
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - Y Acremann
- Laboratorium für Festkörperphysik, ETH Zürich, 8093 Zürich, Switzerland
| | - W Wurth
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
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10
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Beyer H, Rohde G, Grubišić Čabo A, Stange A, Jacobsen T, Bignardi L, Lizzit D, Lacovig P, Sanders CE, Lizzit S, Rossnagel K, Hofmann P, Bauer M. 80% Valley Polarization of Free Carriers in Singly Oriented Single-Layer WS_{2} on Au(111). Phys Rev Lett 2019; 123:236802. [PMID: 31868459 DOI: 10.1103/physrevlett.123.236802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Indexed: 06/10/2023]
Abstract
We employ time- and angle-resolved photoemission spectroscopy to study the spin- and valley-selective photoexcitation and dynamics of free carriers at the K[over ¯] and K[over ¯]^{'} points in singly oriented single-layer WS_{2}/Au(111). Our results reveal that in the valence band maximum an ultimate valley polarization of free holes of 84% can be achieved upon excitation with circularly polarized light at room temperature. Notably, we observe a significantly smaller valley polarization for the photoexcited free electrons in the conduction band minimum. Clear differences in the carrier dynamics between electrons and holes imply intervalley scattering processes into dark states being responsible for the efficient depolarization of the excited electron population.
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Affiliation(s)
- H Beyer
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - G Rohde
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - A Grubišić Čabo
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark
| | - A Stange
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - T Jacobsen
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - L Bignardi
- Department of Physics, University of Trieste, 34127 Trieste, Italy
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - D Lizzit
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - P Lacovig
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - C E Sanders
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell OX11 0QX, United Kingdom
| | - S Lizzit
- Elettra-Sincrotrone Trieste S.C.p.A., 34149 Trieste, Italy
| | - K Rossnagel
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
- Ruprecht-Haensel-Labor, Christian-Albrechts-Universität zu Kiel und Deutsches Elektronen-Synchrotron DESY, 24098 Kiel und 22607 Hamburg, Germany
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - P Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark
| | - M Bauer
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
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11
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Jong JD, Stoisser B, Wagner K, Tomassen M, Driessen J, Hofmann P, Putzka HA, Antalick JP, Cowles J, Felgueiras I, Hofmann P, Johannsen FH, Putzka HA, Stepinska A, Stoisser; B, Thalmann A, van der Kamp HJ, van Schalm K. Determination of Maduramicin in Feedingstuffs and Premixtures by Liquid Chromatography: Development, Validation, and Interlaboratory Study. J AOAC Int 2019. [DOI: 10.1093/jaoac/87.5.1033] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
A reversed-phase liquid chromatography method for determination of maduramicin in feedingstuffs and premixtures was developed, validated, and interlaboratory studied. The extraction solvent was methanol. Maduramicin was detected at 520 nm after postcolumn derivatization with vanillin.
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Affiliation(s)
- Jacob De Jong
- RIKILT-Institute of Food Safety, PO Box 230, 6700 AE, Wageningen, The Netherlands
| | - Bernd Stoisser
- Austrian Agency for Health and Food Safety, Agricultural Inspection Service and Research Centre Vienna (AGES-LWVIE), Spargelfeldstraße 191, A-1226 Vienna, Austria
| | - Karl Wagner
- Austrian Agency for Health and Food Safety, Agricultural Inspection Service and Research Centre Vienna (AGES-LWVIE), Spargelfeldstraße 191, A-1226 Vienna, Austria
| | | | - Jaap Driessen
- Hoffmann-La Roche Ltd., Bau 71/248, CH-4070, Basel, Switzerland
| | - Peter Hofmann
- RIKILT-Institute of Food Safety, PO Box 230, 6700 AE, Wageningen, The Netherlands
| | - Hans-Artur Putzka
- Universität Hamburg, Institut für Angewandte Botanik, PO Box 302762, D-20309, Hamburg, Germany
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12
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Tkáč V, Výborný K, Komanický V, Warmuth J, Michiardi M, Ngankeu AS, Vondráček M, Tarasenko R, Vališka M, Stetsovych V, Carva K, Garate I, Bianchi M, Wiebe J, Holý V, Hofmann P, Springholz G, Sechovský V, Honolka J. Influence of an Anomalous Temperature Dependence of the Phase Coherence Length on the Conductivity of Magnetic Topological Insulators. Phys Rev Lett 2019; 123:036406. [PMID: 31386447 DOI: 10.1103/physrevlett.123.036406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 05/08/2019] [Indexed: 06/10/2023]
Abstract
Magnetotransport constitutes a useful probe to understand the interplay between electronic band topology and magnetism in spintronic devices. A recent theory of Lu and Shen [Phys. Rev. Lett. 112, 146601 (2014)PRLTAO0031-900710.1103/PhysRevLett.112.146601] on magnetically doped topological insulators predicts that quantum corrections Δκ to the temperature dependence of conductivity can change sign across the Curie transition. This phenomenon has been attributed to a suppression of the Berry phase of the topological surface states at the Fermi level, caused by a magnetic energy gap. Here, we demonstrate experimentally that Δκ can reverse its sign even when the Berry phase at the Fermi level remains unchanged. The contradictory behavior to theory predictions is resolved by extending the model by Lu and Shen to a nonmonotonic temperature scaling of the inelastic scattering length showing a turning point at the Curie transition.
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Affiliation(s)
- V Tkáč
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-12116 Prague 2, Czech Republic
- Institute of Physics, P. J. Šafárik University, Park Angelinum 9, 040 01 Košice, Slovak Republic
| | - K Výborný
- Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnická 10, CZ-16253 Praha 6, Czech Republic
| | - V Komanický
- Institute of Physics, P. J. Šafárik University, Park Angelinum 9, 040 01 Košice, Slovak Republic
| | - J Warmuth
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - M Michiardi
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark
| | - A S Ngankeu
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark
| | - M Vondráček
- Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Prague 8, Czech Republic
| | - R Tarasenko
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-12116 Prague 2, Czech Republic
- Institute of Physics, P. J. Šafárik University, Park Angelinum 9, 040 01 Košice, Slovak Republic
| | - M Vališka
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-12116 Prague 2, Czech Republic
| | - V Stetsovych
- Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Prague 8, Czech Republic
| | - K Carva
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-12116 Prague 2, Czech Republic
| | - I Garate
- Département de physique and Institut quantique, Université de Sherbrooke, Sherbrooke (Québec), Canada J1K 2R1
| | - M Bianchi
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark
| | - J Wiebe
- Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - V Holý
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-12116 Prague 2, Czech Republic
| | - Ph Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark
| | - G Springholz
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenbergerstrasse 69, A-4040 Linz, Austria
| | - V Sechovský
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, CZ-12116 Prague 2, Czech Republic
| | - J Honolka
- Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Prague 8, Czech Republic
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13
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Tietze M, Schaumann A, Thomale U, Hofmann P, Tietze A. Dynamic cerebellar herniation in Chiari patients during the cardiac cycle evaluated by dynamic magnetic resonance imaging. Neuroradiology 2019; 61:825-832. [PMID: 31053886 DOI: 10.1007/s00234-019-02203-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 03/28/2019] [Indexed: 12/22/2022]
Abstract
PURPOSE Cerebellar herniation in Chiari patients can be dynamic, following the cerebrospinal fluid pulsatility during the cardiac cycle. We present a voxel intensity distribution method (VIDM) to automatically extract the pulsatility-dependent herniation in time-resolved MRI (CINE MRI) and compare it to the simple linear measurements. The degree of herniation is furthermore compared on CINE and static sequences, and the cerebellar movement is correlated to the presence of hydrocephalus and syringomyelia. METHODS The cerebellar movement in 27 Chiari patients is analyzed with VIDM and the results were compared to linear measurements on an image viewer (visual inspection, VI) using a paired t test. Second, an ANOVA test is applied to compare the degree of herniation on static 3D MRI and CINE. Finally, the Pearson's correlation coefficient is calculated for the correlation between cerebellar movement and the presence of hydrocephalus and syringomyelia. RESULTS VIDM showed significant movement in 85% of our patients. Assuming that movement < 1 mm cannot be detected reliably on an image viewer, VI identified movement in 29.6% of the patients (p = 0.002). The herniation was greater on static sequences than on CINE in most cases, but this was not statistically significant. The cerebellar movement was not correlated with hydrocephalus or syringomyelia (Pearson's coefficient < 0.3). CONCLUSIONS VIDM is a sensitive method to detect tissue movement on CINE MRI and could be used for Chiari patients, but also for the evaluation of cyst membranes, ventriculostomies, etc. The cerebellar movement appears not to correlate with hydrocephalus and syringomyelia in Chiari patients.
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Affiliation(s)
- M Tietze
- Pediatric Neurosurgery, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Humboldt-Universität zu Berlin, Berlin, Germany
| | - A Schaumann
- Pediatric Neurosurgery, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Humboldt-Universität zu Berlin, Berlin, Germany
| | - U Thomale
- Pediatric Neurosurgery, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Ph Hofmann
- Department of Physics and Astronomy and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus, Denmark
| | - A Tietze
- Institute of Neuroradiology, Charité Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Humboldt-Universität zu Berlin, Berlin, Germany.
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14
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Moser O, Eckstein ML, Mueller A, Birnbaumer P, Aberer F, Koehler G, Sourij C, Kojzar H, Holler P, Simi H, Pferschy P, Dietz P, Bracken RM, Hofmann P, Sourij H. Impact of physical exercise on sensor performance of the FreeStyle Libre intermittently viewed continuous glucose monitoring system in people with Type 1 diabetes: a randomized crossover trial. Diabet Med 2019; 36:606-611. [PMID: 30677187 DOI: 10.1111/dme.13909] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/05/2018] [Indexed: 01/10/2023]
Abstract
AIMS To evaluate the sensor performance of the FreeStyle Libre intermittently viewed continuous glucose monitoring system using reference blood glucose levels during moderate-intensity exercise while on either full or reduced basal insulin dose in people with Type 1 diabetes. METHODS Ten participants with Type 1 diabetes [four women, mean ± sd age 31.4 ± 9.0 years, BMI 25.5±3.8 kg/m2 , HbA1c 55±7 mmol/mol (7.2±0.6%)] exercised on a cycle ergometer for 55 min at a moderate intensity for 5 consecutive days at the clinical research facility, while receiving either their usual or a 75% basal insulin dose. After a 4-week washout period, participants performed the second exercise period having switched to the alternative basal insulin dose. During exercise, reference capillary blood glucose values were analysed using the fully enzymatic-amperometric method and compared with the interstitial glucose values obtained. Intermittently viewed continuous glucose monitoring accuracy was analysed according to median (interquartile range) absolute relative difference, and Clarke error grid and Bland-Altman analysis for overall glucose levels during exercise, stratified by glycaemic range and basal insulin dosing scheme (P<0.05). RESULTS A total of 845 glucose values were available during exercise to evaluate intermittently viewed continuous glucose monitoring sensor performance. The median (interquartile range) absolute relative difference between the reference values and those obtained by the sensor across the glycaemic range overall was 22 (13.9-29.7)%, and was 36.3 (24.2-45.2)% during hypoglycaemia, 22.8 (14.6-30.6)% during euglycaemia and 15.4 (9-21)% during hyperglycaemia. Usual basal insulin dose was associated with a worse sensor performance during exercise compared with the reduced (75%) basal insulin dose [median (interquartile range) absolute relative difference: 23.7 (17.2-30.7)% vs 20.5 (12-28.1)%; P<0.001). CONCLUSIONS The intermittently viewed continuous glucose monitoring sensor showed diminished accuracy during exercise. Absolute glucose readings derived from the sensor should be used cautiously and need confirmation by additional finger-prick blood glucose measurements.
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Affiliation(s)
- O Moser
- Diabetes Research Group, Medical School, Swansea University, Swansea, UK
- Applied Sport, Technology, Exercise and Medicine Research Centre (A-STEM), College of Engineering, Swansea University, Swansea, UK
| | - M L Eckstein
- Diabetes Research Group, Medical School, Swansea University, Swansea, UK
- Applied Sport, Technology, Exercise and Medicine Research Centre (A-STEM), College of Engineering, Swansea University, Swansea, UK
| | - A Mueller
- Exercise Physiology, Training and Training Therapy Research Group, Institute of Sports Science, Medical University of Graz, Graz, Austria
- Sport Science Laboratory, FH Joanneum University of Applied Science, Bad Gleichenberg, Austria
| | - P Birnbaumer
- Exercise Physiology, Training and Training Therapy Research Group, Institute of Sports Science, Medical University of Graz, Graz, Austria
| | - F Aberer
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - G Koehler
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - C Sourij
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - H Kojzar
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - P Holler
- Sport Science Laboratory, FH Joanneum University of Applied Science, Bad Gleichenberg, Austria
| | - H Simi
- Sport Science Laboratory, FH Joanneum University of Applied Science, Bad Gleichenberg, Austria
| | - P Pferschy
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - P Dietz
- Department of Physical Activity and Public Health, Institute of Sports Science, Medical University of Graz, Graz, Austria
- Institute of Occupational, Social and Environmental Medicine, University Medical Centre of the University of Mainz, Mainz, Germany
| | - R M Bracken
- Diabetes Research Group, Medical School, Swansea University, Swansea, UK
- Applied Sport, Technology, Exercise and Medicine Research Centre (A-STEM), College of Engineering, Swansea University, Swansea, UK
| | - P Hofmann
- Exercise Physiology, Training and Training Therapy Research Group, Institute of Sports Science, Medical University of Graz, Graz, Austria
| | - H Sourij
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
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15
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Li DY, Busch A, Jin HH, Hofmann P, Boon RA, Pelisek J, Paloschi V, Roy J, Eckstein HH, Spin JM, Tsao PS, Maegdefessel L. P3199Long non-coding RNA H19 induces abdominal aortic aneurysms. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy563.p3199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- D Y Li
- Technical University of Munich, Vascular and Endovascular Surgery, Munich, Germany
| | - A Busch
- Technical University of Munich, Vascular and Endovascular Surgery, Munich, Germany
| | - H H Jin
- Karolinska Institute, Stockholm, Sweden
| | - P Hofmann
- JW Goethe University, Frankfurt am Main, Germany
| | - R A Boon
- JW Goethe University, Frankfurt am Main, Germany
| | - J Pelisek
- Technical University of Munich, Vascular and Endovascular Surgery, Munich, Germany
| | - V Paloschi
- Technical University of Munich, Vascular and Endovascular Surgery, Munich, Germany
| | - J Roy
- Karolinska Institute, Stockholm, Sweden
| | - H H Eckstein
- Technical University of Munich, Vascular and Endovascular Surgery, Munich, Germany
| | - J M Spin
- Stanford University Medical Center, Division of Cardiovascular Medicine, Stanford, United States of America
| | - P S Tsao
- Stanford University Medical Center, Division of Cardiovascular Medicine, Stanford, United States of America
| | - L Maegdefessel
- Technical University of Munich, Vascular and Endovascular Surgery, Munich, Germany
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16
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Kröpfl JM, Tschakert G, Stelzer I, Pekovits K, Zelzer S, Dohr G, Holasek S, Stojakovic T, Scharnagl H, Spengler CM, Hofmann P. Acute Exercise-Induced Circulating Haematopoietic Stem and Progenitor Cells in Cardiac Patients - A Case Series. Heart Lung Circ 2018; 28:e54-e58. [PMID: 29933914 DOI: 10.1016/j.hlc.2018.05.095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 04/18/2018] [Accepted: 05/01/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Exercise-induced circulating haematopoietic stem and progenitor cell (HPC) number has been discussed in the context of regeneration in heart disease patients. OBJECTIVE The aim of this pilot study was to compare the effect of different exercise protocols usually applied in cardiac rehabilitation on the number of acute, exercise-induced HPCs, related to potential mediators, e.g. biomarkers of sympathetic and oxidative stress, and inflammation. METHODS This is a case series comprising seven patients suffering from coronary heart disease (CHD) undertaken at the Center for Ambulant Cardiac Rehabilitation. Patients (n=6) performed two exercise modes (constant-load, CLE; high-intensity interval, HIIE) in randomised order. Venous blood was drawn before and immediately after each test to assess CD34+/CD45+ HPC number by flow cytometry and biomarkers in blood plasma. The primary outcome was the change in HPC number, the secondary outcomes were changes in sympathetic/oxidative stress and markers of inflammation. RESULTS Both exercise modes resulted in a non-significant increase in HPC number after exercise, even when the results of both tests were combined. Overall, free norepinephrine increased significantly and was positively related to exercise-induced HPC number (r=0.70, p<0.05). Markers of sympathetic activation (fNE), oxidative stress (myeloperoxidase) and inflammation (interleukin-6) significantly increased after CLE and HIIE with no difference between tests. CONCLUSIONS Interestingly, acute CLE and HIIE did not stimulate significant HPC mobilisation in CHD, although both exercise modes elevated circulating concentrations of sympathetic activation. Haematopoietic stem and progenitor cell mobilisation could be blunted due to disease-related bone-marrow exhaustion.
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Affiliation(s)
- J M Kröpfl
- Exercise Physiology Lab, Institute of Human Movement Sciences and Sport, ETH Zurich, Zurich, Switzerland; Institute of Biophysics, Medical University of Graz, Graz, Austria.
| | - G Tschakert
- Exercise Physiology and Training Research Group, Institute of Sports Science, University of Graz, Graz, Austria
| | - I Stelzer
- Institute of Medical and Chemical Laboratory Diagnostics, LKH Hochsteiermark, Leoben, Austria
| | - K Pekovits
- Department of Ophthalmology, Medical University Graz, Graz, Austria
| | - S Zelzer
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - G Dohr
- Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - S Holasek
- Institute for Pathophysiology and Immunology, Medical University of Graz, Graz, Austria
| | - T Stojakovic
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - H Scharnagl
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - C M Spengler
- Exercise Physiology Lab, Institute of Human Movement Sciences and Sport, ETH Zurich, Zurich, Switzerland
| | - P Hofmann
- Exercise Physiology and Training Research Group, Institute of Sports Science, University of Graz, Graz, Austria
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17
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Mazzola F, Wells JW, Pakpour-Tabrizi AC, Jackman RB, Thiagarajan B, Hofmann P, Miwa JA. Simultaneous Conduction and Valence Band Quantization in Ultrashallow High-Density Doping Profiles in Semiconductors. Phys Rev Lett 2018; 120:046403. [PMID: 29437461 DOI: 10.1103/physrevlett.120.046403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 12/08/2017] [Indexed: 06/08/2023]
Abstract
We demonstrate simultaneous quantization of conduction band (CB) and valence band (VB) states in silicon using ultrashallow, high-density, phosphorus doping profiles (so-called Si:P δ layers). We show that, in addition to the well-known quantization of CB states within the dopant plane, the confinement of VB-derived states between the subsurface P dopant layer and the Si surface gives rise to a simultaneous quantization of VB states in this narrow region. We also show that the VB quantization can be explained using a simple particle-in-a-box model, and that the number and energy separation of the quantized VB states depend on the depth of the P dopant layer beneath the Si surface. Since the quantized CB states do not show a strong dependence on the dopant depth (but rather on the dopant density), it is straightforward to exhibit control over the properties of the quantized CB and VB states independently of each other by choosing the dopant density and depth accordingly, thus offering new possibilities for engineering quantum matter.
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Affiliation(s)
- F Mazzola
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - J W Wells
- Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - A C Pakpour-Tabrizi
- London Centre for Nanotechnology and Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | - R B Jackman
- London Centre for Nanotechnology and Department of Electronic and Electrical Engineering, University College London, 17-19 Gordon Street, London WC1H 0AH, United Kingdom
| | | | - Ph Hofmann
- Department of Physics and Astronomy and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Ny Munkegade 120, DK-8000 Aarhus, Denmark
| | - J A Miwa
- Department of Physics and Astronomy and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Ny Munkegade 120, DK-8000 Aarhus, Denmark
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18
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Manna S, Kamlapure A, Cornils L, Hänke T, Hedegaard EMJ, Bremholm M, Iversen BB, Hofmann P, Wiebe J, Wiesendanger R. Interfacial superconductivity in a bi-collinear antiferromagnetically ordered FeTe monolayer on a topological insulator. Nat Commun 2017; 8:14074. [PMID: 28094258 PMCID: PMC5247605 DOI: 10.1038/ncomms14074] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 11/25/2016] [Indexed: 11/09/2022] Open
Abstract
The discovery of high-temperature superconductivity in Fe-based compounds triggered numerous investigations on the interplay between superconductivity and magnetism, and on the enhancement of transition temperatures through interface effects. It is widely believed that the emergence of optimal superconductivity is intimately linked to the suppression of long-range antiferromagnetic (AFM) order, although the exact microscopic picture remains elusive because of the lack of atomically resolved data. Here we present spin-polarized scanning tunnelling spectroscopy of ultrathin FeTe1-xSex (x=0, 0.5) films on bulk topological insulators. Surprisingly, we find an energy gap at the Fermi level, indicating superconducting correlations up to Tc∼6 K for one unit cell FeTe grown on Bi2Te3, in contrast to the non-superconducting bulk FeTe. The gap spatially coexists with bi-collinear AFM order. This finding opens perspectives for theoretical studies of competing orders in Fe-based superconductors and for experimental investigations of exotic phases in superconducting layers on topological insulators.
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Affiliation(s)
- S Manna
- Department of Physics, University of Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany
| | - A Kamlapure
- Department of Physics, University of Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany
| | - L Cornils
- Department of Physics, University of Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany
| | - T Hänke
- Department of Physics, University of Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany
| | - E M J Hedegaard
- Department of Chemistry and iNANO, Center for Materials Crystallography, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - M Bremholm
- Department of Chemistry and iNANO, Center for Materials Crystallography, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - B B Iversen
- Department of Chemistry and iNANO, Center for Materials Crystallography, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Ph Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, DK-8000 Aarhus C, Denmark
| | - J Wiebe
- Department of Physics, University of Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany
| | - R Wiesendanger
- Department of Physics, University of Hamburg, Jungiusstrasse 11, D-20355 Hamburg, Germany
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Grey D, Cook M, Hofmann P, Mwanga A, Akoko L, Mchembe M, Schecter W. An alliance of educators to support post graduate surgical training in
Tanzania. Ann Glob Health 2016. [DOI: 10.1016/j.aogh.2016.04.078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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20
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Stelzer I, Kröpfl JM, Fuchs R, Pekovits K, Mangge H, Raggam RB, Gruber HJ, Prüller F, Hofmann P, Truschnig-Wilders M, Obermayer-Pietsch B, Haushofer AC, Kessler HH, Mächler P. Ultra-endurance exercise induces stress and inflammation and affects circulating hematopoietic progenitor cell function. Scand J Med Sci Sports 2014; 25:e442-50. [PMID: 25438993 DOI: 10.1111/sms.12347] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2014] [Indexed: 01/18/2023]
Abstract
Although amateur sports have become increasingly competitive within recent decades, there are as yet few studies on the possible health risks for athletes. This study aims to determine the impact of ultra-endurance exercise-induced stress on the number and function of circulating hematopoietic progenitor cells (CPCs) and hematological, inflammatory, clinical, metabolic, and stress parameters in moderately trained amateur athletes. Following ultra-endurance exercise, there were significant increases in leukocytes, platelets, interleukin-6, fibrinogen, tissue enzymes, blood lactate, serum cortisol, and matrix metalloproteinase-9. Ultra-endurance exercise did not influence the number of CPCs but resulted in a highly significant decline of CPC functionality after the competition. Furthermore, Epstein-Barr virus was seen to be reactivated in one of seven athletes. The link between exercise-induced stress and decline of CPC functionality is supported by a negative correlation between cortisol and CPC function. We conclude that ultra-endurance exercise induces metabolic stress and an inflammatory response that affects not only mature hematopoietic cells but also the function of the immature hematopoietic stem and progenitor cell fraction, which make up the immune system and provide for regeneration.
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Affiliation(s)
- I Stelzer
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - J M Kröpfl
- Institute of Human Movement Sciences and Sport, Exercise Physiology Lab, ETH Zurich, Zurich, Switzerland.,Institute of Biophysics, Medical University of Graz, Graz, Austria
| | - R Fuchs
- Institute of Pathophysiology and Immunology, Medical University of Graz, Graz, Austria
| | - K Pekovits
- Department of Ophthalmology, Medical University of Graz, Graz, Austria
| | - H Mangge
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - R B Raggam
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - H-J Gruber
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - F Prüller
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - P Hofmann
- Institute of Sports Science, Karl-Franzens-University of Graz, Graz, Austria
| | - M Truschnig-Wilders
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - B Obermayer-Pietsch
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - A C Haushofer
- Institute of Medical and Chemical Laboratory Diagnostics Wels-Grieskirchen, Wels-Grieskirchen, Austria
| | - H H Kessler
- Research Unit Molecular Diagnostics, IHMEM, Medical University of Graz, Graz, Austria
| | - P Mächler
- Center for Cardiac Rehabilitation, SKA-PVA St. Radegund, Graz, Austria
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21
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Redler S, Birch P, Drichel D, Hofmann P, Dobson K, Böhmer A, Becker J, Giehl K, Tazi-Ahnini R, Kruse R, Wolff H, Miesel A, Fischer T, Böhm M, Nuwayhid R, Garcia Bartels N, Lutz G, Becker T, Blume-Peytavi U, Nöthen M, Messenger A, Betz R. The oestrogen receptor 2 (ESR2) gene in female-pattern hair loss: replication of association with rs10137185 in German patients. Br J Dermatol 2014; 170:982-5. [DOI: 10.1111/bjd.12756] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Redler
- Institute of Human Genetics; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
| | - P. Birch
- Department of Dermatology; Royal Hallamshire Hospital; Sheffield U.K
| | - D. Drichel
- German Center for Neurodegenerative Diseases (DZNE); Bonn Germany
| | - P. Hofmann
- Institute of Human Genetics; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
- Department of Genomics, Life & Brain Center; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
| | - K. Dobson
- Department of Dermatology; Royal Hallamshire Hospital; Sheffield U.K
| | - A.C. Böhmer
- Institute of Human Genetics; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
- Department of Genomics, Life & Brain Center; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
| | - J. Becker
- Institute of Human Genetics; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
- Department of Genomics, Life & Brain Center; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
| | - K.A. Giehl
- Department of Dermatology; University of Munich; Munich Germany
| | - R. Tazi-Ahnini
- Department of Infection and Immunity; University of Sheffield; Sheffield U.K
| | - R. Kruse
- Dermatological Practice; Paderborn Germany
| | - H. Wolff
- Department of Dermatology; University of Munich; Munich Germany
| | - A. Miesel
- Department of Dermatology; University of Lübeck; Lübeck Germany
| | - T. Fischer
- Department of Dermatology; University of Lübeck; Lübeck Germany
| | - M. Böhm
- Department of Dermatology; Laboratory for Neuroendocrinology of the Skin and Interdisciplinary Endocrinology; University of Münster; Münster Germany
| | - R. Nuwayhid
- Clinical Research Center for Hair and Skin Science; Department of Dermatology and Allergy; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - N. Garcia Bartels
- Clinical Research Center for Hair and Skin Science; Department of Dermatology and Allergy; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - G. Lutz
- Dermatological Practice, Hair & Nail; Wesseling Germany
| | - T. Becker
- German Center for Neurodegenerative Diseases (DZNE); Bonn Germany
- Institute for Medical Biometry Informatics and Epidemiology; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
| | - U. Blume-Peytavi
- Clinical Research Center for Hair and Skin Science; Department of Dermatology and Allergy; Charité-Universitätsmedizin Berlin; Berlin Germany
| | - M.M. Nöthen
- Institute of Human Genetics; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
- Department of Genomics, Life & Brain Center; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
| | - A.G. Messenger
- Department of Dermatology; Royal Hallamshire Hospital; Sheffield U.K
| | - R.C. Betz
- Institute of Human Genetics; University of Bonn; Sigmund-Freud-Street 25 D-53127 Bonn Germany
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22
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23
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Moser O, Müller A, Gröschl W, Köhler G, Hofmann P. Zusammenhang zwischen dem Abfall der Blutzucker-Konzentration und definierten physischen Belastungen am Fahrrad-Ergometer bei Diabetes mellitus Typ I - Einzelfallstudie. DIABETOL STOFFWECHS 2013. [DOI: 10.1055/s-0033-1347769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Kroepfl J, Stelzer I, Pekovits K, Fuchs R, Poncza B, Allard N, Hofmann P, Dohr G, Wallner-Liebmann S, Domej W, Mueller W. Norepinephrine directly influences circulating hematopoietic progenitor cell functionality in vitro: a possible hint for an exercise-induced stress model. Cytotherapy 2013. [DOI: 10.1016/j.jcyt.2013.01.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Leuenberger D, Yanagisawa H, Roth S, Dil JH, Wells JW, Hofmann P, Osterwalder J, Hengsberger M. Excitation of coherent phonons in the one-dimensional Bi(114) surface. Phys Rev Lett 2013; 110:136806. [PMID: 23581358 DOI: 10.1103/physrevlett.110.136806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Indexed: 06/02/2023]
Abstract
We present time-resolved photoemission experiments from a peculiar bismuth surface, Bi(114). The strong one-dimensional character of this surface is reflected in the Fermi surface, which consists of spin-polarized straight lines. Our results show that the depletion of the surface state and the population of the bulk conduction band after the initial optical excitation persist for very long times. The disequilibrium within the hot electron gas along with strong electron-phonon coupling cause a displacive excitation of coherent phonons, which in turn are reflected in coherent modulations of the electronic states. Beside the well-known A(1g) bulk phonon mode at 2.76 THz, the time-resolved photoelectron spectra reveal a second mode at 0.72 THz which can be attributed to an optical surface phonon mode along the atomic rows of the Bi(114) surface.
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Affiliation(s)
- D Leuenberger
- Physics Institute, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
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26
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Schlenk T, Bianchi M, Koleini M, Eich A, Pietzsch O, Wehling TO, Frauenheim T, Balatsky A, Mi JL, Iversen BB, Wiebe J, Khajetoorians AA, Hofmann P, Wiesendanger R. Controllable magnetic doping of the surface state of a topological insulator. Phys Rev Lett 2013; 110:126804. [PMID: 25166834 DOI: 10.1103/physrevlett.110.126804] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Indexed: 05/04/2023]
Abstract
A combined experimental and theoretical study of doping individual Fe atoms into Bi(2)Se(3) is presented. It is shown through a scanning tunneling microscopy study that single Fe atoms initially located at hollow sites on top of the surface (adatoms) can be incorporated into subsurface layers by thermally activated diffusion. Angle-resolved photoemission spectroscopy in combination with ab initio calculations suggest that the doping behavior changes from electron donation for the Fe adatom to neutral or electron acceptance for Fe incorporated into substitutional Bi sites. According to first principles calculations within density functional theory, these Fe substitutional impurities retain a large magnetic moment, thus presenting an alternative scheme for magnetically doping the topological surface state. For both types of Fe doping, we see no indication of a gap at the Dirac point.
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Affiliation(s)
- T Schlenk
- Institute for Applied Physics, Universität Hamburg, D-20355 Hamburg, Germany
| | - M Bianchi
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark
| | - M Koleini
- Bremen Center for Computational Materials Science, University of Bremen, D-28359 Bremen, Germany
| | - A Eich
- Institute for Applied Physics, Universität Hamburg, D-20355 Hamburg, Germany
| | - O Pietzsch
- Institute for Applied Physics, Universität Hamburg, D-20355 Hamburg, Germany
| | - T O Wehling
- Bremen Center for Computational Materials Science, University of Bremen, D-28359 Bremen, Germany and Institute for Theoretical Physics, University of Bremen, D-28359 Bremen, Germany
| | - T Frauenheim
- Bremen Center for Computational Materials Science, University of Bremen, D-28359 Bremen, Germany
| | - A Balatsky
- Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA and Nordic Institute for Theoretical Physics (NORDITA), S-106 91 Stockholm, Sweden
| | - J-L Mi
- Center for Materials Crystallography, Department of Chemistry, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark
| | - B B Iversen
- Center for Materials Crystallography, Department of Chemistry, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark
| | - J Wiebe
- Institute for Applied Physics, Universität Hamburg, D-20355 Hamburg, Germany
| | - A A Khajetoorians
- Institute for Applied Physics, Universität Hamburg, D-20355 Hamburg, Germany
| | - Ph Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark
| | - R Wiesendanger
- Institute for Applied Physics, Universität Hamburg, D-20355 Hamburg, Germany
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27
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Bottomley D, Stuckert J, Hofmann P, Tocheny L, Hugon M, Journeau C, Clément B, Weber S, Guentay S, Hozer Z, Herranz L, Schumm A, Oriolo F, Altstadt E, Krause M, Fischer M, Khabensky V, Bechta S, Veshchunov M, Palagin A, Kiselev A, Nalivaev V, Goryachev A, Zhdanov V, Baklanov V. Severe accident research in the core degradation area: An example of effective international cooperation between the European Union (EU) and the Commonwealth of Independent States (CIS) by the International Science and Technology Center. Nuclear Engineering and Design 2012. [DOI: 10.1016/j.nucengdes.2012.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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28
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Honolka J, Khajetoorians AA, Sessi V, Wehling TO, Stepanow S, Mi JL, Iversen BB, Schlenk T, Wiebe J, Brookes NB, Lichtenstein AI, Hofmann P, Kern K, Wiesendanger R. In-plane magnetic anisotropy of Fe atoms on Bi2Se3(111). Phys Rev Lett 2012; 108:256811. [PMID: 23004640 DOI: 10.1103/physrevlett.108.256811] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Indexed: 06/01/2023]
Abstract
The robustness of the gapless topological surface state hosted by a 3D topological insulator against perturbations of magnetic origin has been the focus of recent investigations. We present a comprehensive study of the magnetic properties of Fe impurities on the prototypical 3D topological insulator Bi(2)Se(3) using local low-temperature scanning tunneling spectroscopy and integral x-ray magnetic circular dichroism techniques. Single Fe adatoms on the Bi(2)Se(3) surface, in the coverage range ≈ 1% of a monolayer, are heavily relaxed into the surface and exhibit a magnetic easy axis within the surface plane, contrary to what was assumed in recent investigations on the supposed opening of a gap. Using ab initio approaches, we demonstrate that an in-plane easy axis arises from the combination of the crystal field and dynamic hybridization effects.
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Affiliation(s)
- J Honolka
- Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
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29
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King PDC, Hatch RC, Bianchi M, Ovsyannikov R, Lupulescu C, Landolt G, Slomski B, Dil JH, Guan D, Mi JL, Rienks EDL, Fink J, Lindblad A, Svensson S, Bao S, Balakrishnan G, Iversen BB, Osterwalder J, Eberhardt W, Baumberger F, Hofmann P. Large tunable Rashba spin splitting of a two-dimensional electron gas in Bi2Se3. Phys Rev Lett 2011; 107:096802. [PMID: 21929260 DOI: 10.1103/physrevlett.107.096802] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Indexed: 05/13/2023]
Abstract
We report a Rashba spin splitting of a two-dimensional electron gas in the topological insulator Bi(2)Se(3) from angle-resolved photoemission spectroscopy. We further demonstrate its electrostatic control, and show that spin splittings can be achieved which are at least an order-of-magnitude larger than in other semiconductors. Together these results show promise for the miniaturization of spintronic devices to the nanoscale and their operation at room temperature.
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Affiliation(s)
- P D C King
- School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, United Kingdom
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30
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Li X, Breitkreutz H, Burfeindt J, Bernhardt HG, Trieloff M, Hopp J, Jessberger EK, Schwarz WH, Hofmann P, Hiesinger H. Evaluation of neutron sources for ISAGE-in-situ-NAA for a future lunar mission. Appl Radiat Isot 2011; 69:1625-9. [PMID: 21680192 DOI: 10.1016/j.apradiso.2011.05.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 05/19/2011] [Indexed: 11/27/2022]
Abstract
For a future Moon landing, a concept for an in-situ NAA involving age determination using the (40)Ar-(39)Ar method is developed. A neutron source (252)Cf is chosen for sample irradiation on the Moon. A special sample-in-source irradiation geometry is designed to provide a homogeneous distribution of neutron flux at the irradiation position. Using reflector, the neutron flux is likely to increase by almost 200%. Sample age of 1Ga could be determined. Elemental analysis using INAA is discussed.
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Affiliation(s)
- X Li
- Forschungs-Neutronenquelle Heinz Maier-Leibnitz, FRM II, Technische Universität München, Garching, Germany.
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31
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King PDC, Veal TD, McConville CF, Zúñiga-Pérez J, Muñoz-Sanjosé V, Hopkinson M, Rienks EDL, Jensen MF, Hofmann P. Surface band-gap narrowing in quantized electron accumulation layers. Phys Rev Lett 2010; 104:256803. [PMID: 20867408 DOI: 10.1103/physrevlett.104.256803] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Indexed: 05/29/2023]
Abstract
An energy gap between the valence and the conduction band is the defining property of a semiconductor, and the gap size plays a crucial role in the design of semiconductor devices. We show that the presence of a two-dimensional electron gas near to the surface of a semiconductor can significantly alter the size of its band gap through many-body effects caused by its high electron density, resulting in a surface band gap that is much smaller than that in the bulk. Apart from reconciling a number of disparate previous experimental findings, the results suggest an entirely new route to spatially inhomogeneous band-gap engineering.
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Affiliation(s)
- P D C King
- Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom.
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32
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Hofmann P, Knözinger E, Diwald O, Mustafa A. Thermally stable CaO surfaces on highly dispersed MgO - New aspects for methane activation. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bbpc.19971011135] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Eissner B, Hofmann P. Wassergeburt –„Wellnessgeburten“ mit erhöhtem Risiko? Geburtshilfe Frauenheilkd 2010. [DOI: 10.1055/s-0030-1254924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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35
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Speel EJM, Schmidt A, Baumann M, Haesevoets A, Diebold J, Hofmann P, Kurrer M, Willi N, Offner F, Sauter G, Zsikla V, Cathomas G. Abstract 5352: A high percentage of Merkel cell carcinomas is biologically associated with Merkel cell polyomavirus. Cancer Res 2010. [DOI: 10.1158/1538-7445.am10-5352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Merkel cell polyomavirus (MCPyV) DNA has been detected by PCR in 75-100% of Merkel cell carcinomas (MCC), an aggressive neuroendocrine skin cancer. MCPyV is a 5.4 kb DNA virus that expresses tumor (T) antigen in tumor tissues. The aim of this study was to analyze which subset of MCC is biologically associated with MCPyV using various viral detection methods.
Genomic DNA isolated from paraffin-embedded tissue of 61 MCC was analyzed by MCPyV-specific PCR. Using a 5kb MCPyV DNA probe, the physical status of MCPyV was determined by fluorescence in situ hybridization (FISH) using tyramide signal amplification and ApoTome microscopy. Expression of large T antigen was assessed by immunohistochemistry (IHC) using monoclonal antibody CM2B4 (kindly provided by Y. Chang).
A total of 44 of 61 (72%) MCC were positive for MCPyV by PCR. 34 of these 44 cases (77%) were also positive for MCPyV by FISH and 28 (64%) showed strong nuclear large T antigen expression by IHC. In contrast, none of the 17 PCR-negative tumors showed FISH signals and only 1 case showed a weak immunostaining for large T antigen. FISH analysis showed in 16 cases (47%) tumor nuclei with a single punctate signal indicating viral integration. In 8 of these tumors also areas were observed with a granular pattern with >1 nuclear signals varying significantly in size and intensity, indicating the presence of episomal viral DNA and/or RNA. In the remaining 18 cases (53%) an exclusive granular FISH pattern was observed.
Our data indicate that a subset of MCC is caused by MCPyV as determined by PCR, FISH and IHC analysis (46% is positive with all 3 detection methods). FISH and IHC showed a strong positive and negative concordance. FISH signal evaluation furthermore suggests viral integration in half of the positive MCC and a non-clonal viral persistence in the remaining positive cases. Further studies have to validate these findings and elucidate the molecular mechanisms underlying MCV-positive and -negative MCC development.
Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5352.
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Affiliation(s)
| | | | - M Baumann
- 2Kantonales Institute for Pathology, Liestal, Switzerland
| | | | - J Diebold
- 3Pathology Institute, Luzern, Switzerland
| | - P Hofmann
- 4Laboratory for Anatomy and Pathology, Nice, France
| | | | - N Willi
- 2Kantonales Institute for Pathology, Liestal, Switzerland
| | - F Offner
- 6Akademisches Lehrkrankenhaus, Feldkirch, Austria
| | - Guido Sauter
- 7University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - V Zsikla
- 2Kantonales Institute for Pathology, Liestal, Switzerland
| | - Gieri Cathomas
- 2Kantonales Institute for Pathology, Liestal, Switzerland
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36
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Song F, Wells JW, Handrup K, Li ZS, Bao SN, Schulte K, Ahola-Tuomi M, Mayor LC, Swarbrick JC, Perkins EW, Gammelgaard L, Hofmann P. Direct measurement of electrical conductance through a self-assembled molecular layer. Nat Nanotechnol 2009; 4:373-376. [PMID: 19498399 DOI: 10.1038/nnano.2009.82] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Accepted: 03/17/2009] [Indexed: 05/27/2023]
Abstract
The self-assembly of organic molecules on surfaces is a promising approach for the development of nanoelectronic devices. Although a variety of strategies have been used to establish stable links between molecules, little is known about the electrical conductance of these links. Extended electronic states, a prerequisite for good conductance, have been observed for molecules adsorbed on metal surfaces. However, direct conductance measurements through a single layer of molecules are only possible if the molecules are adsorbed on a poorly conducting substrate. Here we use a nanoscale four-point probe to measure the conductivity of a self-assembled layer of cobalt phthalocyanine on a silver-terminated silicon surface as a function of thickness. For low thicknesses, the cobalt phthalocyanine molecules lie flat on the substrate, and their main effect is to reduce the conductivity of the substrate. At higher thicknesses, the cobalt phthalocyanine molecules stand up to form stacks and begin to conduct. These results connect the electronic structure and orientation of molecular monolayer and few-layer systems to their transport properties, and should aid in the rational design of future devices.
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Affiliation(s)
- F Song
- Institute for Storage Ring Facilities, and Interdisciplinary Nanoscience Center, University of Aarhus, Aarhus C, Denmark
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37
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Hofmann P. Untersuchung der Desinfektionskraft van Sepso-Tinktur im Vergleich zu der offizinellen Jodtinktur. Dtsch Med Wochenschr 2009. [DOI: 10.1055/s-0028-1123200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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38
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Eissner B, Hofmann P. Wassergeburt –„Wellnessgeburten“ mit erhöhtem Risiko? Geburtshilfe Frauenheilkd 2009. [DOI: 10.1055/s-0029-1225084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Wells JW, Dil JH, Meier F, Lobo-Checa J, Petrov VN, Osterwalder J, Ugeda MM, Fernandez-Torrente I, Pascual JI, Rienks EDL, Jensen MF, Hofmann P. Nondegenerate metallic States on Bi(114): a one-dimensional topological metal. Phys Rev Lett 2009; 102:096802. [PMID: 19392548 DOI: 10.1103/physrevlett.102.096802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Indexed: 05/27/2023]
Abstract
The (114) surface of the semimetal Bi is found to support a quasi-one-dimensional, metallic surface state. As required by symmetry, the state is degenerate along the Gamma-Y line of the surface Brillouin zone with a highest binding energy of approximately 150 meV. In the Gamma-X direction the degeneracy is lifted by the strong spin-orbit splitting in Bi, as directly shown by spin-resolved photoemission. This results in a Fermi contour consisting of two closely separated, parallel lines of opposite spin direction. It is argued that similar states on related insulators would give rise to a one-dimensional quantum spin Hall effect.
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Affiliation(s)
- J W Wells
- Institute for Storage Ring Facilities (ISA) and Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark
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Abstract
Several approaches for surface-sensitive conductance measurements are reviewed. Particular emphasis is placed on nanoscale multi-point probe techniques. The results for two model systems, which have given rise to some dispute, are discussed in detail: Si(111)(7 × 7) and ([Formula: see text])Ag-Si(111). Other recent examples are also given, such as phase transitions in quasi-one-dimensional structures on semiconductor surfaces and the surface sheet conductivity of Bi(111), the surface of a semimetal.
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Zöller M, Grevot A, Mätz-Rensing K, Hofmann P, Jurek V, Schulz-Schaeffer W, Kaup FJ. Leucoencephalopathy with cerebral calcinosis in a young chimpanzee (Pan troglodytes) - a case report. J Med Primatol 2008; 36:385-90. [PMID: 17976045 DOI: 10.1111/j.1600-0684.2006.00199.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
CASE HISTORY A 4-year-old chimpanzee (Pan troglodytes) had a clinical history of a 2-year progressive central nervous dysfunction including convulsions and severe paralysis. RESULTS Gross pathology revealed cerebral atrophy, ventricular enlargement and a severe encephalomalacia with extensive calcifications. Histologically, the white matter showed diffuse demyelination as well as vascular and perivascular calcifications which also involved the basal ganglia. Blood vessels with less distinctive calcium deposits exhibited periodic acid Schiff positive hyalinosis. Large areas of necrosis, hemorrhage and intense gliosis were also present. Activation of astrocytes and macrophages was confirmed by immunohistochemical methods. CONCLUSIONS The etiology of the leucoencepalopathy could not be ascertained by macroscopic, histological and immunohistochemical examinations. Potential differential diagnoses include the rarely occurring Fahr's disease in humans, arteriosclerosis, storage disease and the Aicardi-Goutières syndrome. Based on the results of the postmortal examinations Fahr's disease is regarded as the most likely diagnosis in the present case of the chimpanzee.
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Affiliation(s)
- M Zöller
- Department of Infectious Pathology, German Primate Center, Göttingen, Germany.
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Schmidt EZ, Reininghaus B, Enzinger C, Ebner C, Hofmann P, Kapfhammer HP. Changes in brain metabolism after ECT-positron emission tomography in the assessment of changes in glucose metabolism subsequent to electroconvulsive therapy--lessons, limitations and future applications. J Affect Disord 2008; 106:203-8. [PMID: 17662472 DOI: 10.1016/j.jad.2007.06.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 06/19/2007] [Accepted: 06/20/2007] [Indexed: 11/18/2022]
Abstract
BACKGROUND Electroconvulsive therapy (ECT) has been used as an effective treatment option in severe and treatment resistant cases of depression for decades. However the mode of action of ECT is still not fully understood. Advances in neuroimaging created new possibilities to understand the functional changes of the human brain. METHODS Literature review of studies assessing possible changes in cerebral glucose metabolism pre- and post-ECT by PET, identified by PubMed. RESULTS Studies were limited by small sample size, inhomogeneous study population with uni- and bipolar depressive patients and methodological inconsistencies. Despite considerable variance, reduction in glucose metabolism after ECT in bilateral anterior and posterior frontal areas represented the most consistent findings. CONCLUSIONS Future research into this issue should include larger and more consistent cohorts of patients. Assessing clinical improvement of depression after ECT should allow to correlate changes in brain glucose metabolism with functional scores. Follow up PET scans after six or twelve months should be performed to test if changes in brain metabolism are persistent.
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Affiliation(s)
- E Z Schmidt
- Department of Psychiatry, Medical University Graz, Auenbruggerplatz 31, 8036 Graz, Austria.
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Hack G, Hofmann P, Brackmann H, Stoeckel H, Pichotka H. Erste Erfahrungen mit rückenmarksnahen Regionalanästhesietechniken beim Hämophiliepatienten. Anasthesiol Intensivmed Notfallmed Schmerzther 2008. [DOI: 10.1055/s-2007-1005121] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Bornemann A, Norris RD, Friedrich O, Beckmann B, Schouten S, Damste JSS, Vogel J, Hofmann P, Wagner T. Isotopic Evidence for Glaciation During the Cretaceous Supergreenhouse. Science 2008; 319:189-92. [DOI: 10.1126/science.1148777] [Citation(s) in RCA: 201] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Hofmann P, Jürimäe T, Jürimäe J, Purge P, Maestu J, Wonisch M, Pokan R, von Duvillard SP. HRTP, Prolonged Ergometer Exercise, and Single Sculling. Int J Sports Med 2007; 28:964-9. [PMID: 17534783 DOI: 10.1055/s-2007-965074] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The use of the heart rate turn point (HRTP) to set target heart rate (THR) for prolonged rowing ergometer (E) and single scull rowing (R) was evaluated. Ten trained subjects (age 21.3 +/- 4.0 yrs; VO (2max) 4.77 +/- 0.62 l . min-1) performed incremental exercise tests and 30-min prolonged E and R. Expired air and heart rate (HR) were measured continuously. During E and R, blood lactate concentration (La) was measured at rest and after 5, 10, 20, and 30 min. HRTP and V (E)TP (2) were determined as the deflection point of the heart rate performance curve and the second TP in minute ventilation (V. (E)). No significant differences were found for work rate (W), HR, and VO (2) between HRTP and V. (E)TP (2) and they were significantly related (r = 0.94, p < 0.001; r = 0.96, p < 0.001). Mean HR, VO (2), VCO (2), and V. (E) were not significantly different between E and R. La remained at a steady state in both E and R but was slightly higher in E. Tidal volume (V (T)) was found to be lower and breathing rate (BR) was significantly higher in R. HR at HRTP from an incremental rowing ergometer exercise test is valid to establish a THR consistent with constant metabolic training intensity in prolonged ergometer and single scull rowing.
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Affiliation(s)
- P Hofmann
- Institute of Sports Science, KF-University of Graz, Graz, Austria.
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Wells JW, Kallehauge JF, Hofmann P. Thermal switching of the electrical conductivity of Si(111)([Formula: see text])Ag due to a surface phase transition. J Phys Condens Matter 2007; 19:176008. [PMID: 21690945 DOI: 10.1088/0953-8984/19/17/176008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The temperature-dependent surface conductivity of the Si(111)([Formula: see text])Ag surface was measured using a microscopic four-point probe. The conductivity was found to undergo a sharp increase of about three orders of magnitude when the system was heated above about 220 K. This strong conductivity change is reversible and attributed to the phase transition which is generally believed to occur on this surface. It is also shown that, in order to find the true surface conductivity, it is necessary to separate it from the contribution of the bulk and space charge layer. In this work, this is achieved by using a finite-element model. A percolating network of Ag islands on Si(111) was also studied and a much simpler behaviour (compared to that of Si(111)([Formula: see text])Ag) was found. The temperature-dependent conductivity of this system was found to display typical metallic behaviour. The absolute value of the conductivity is comparable to the value expected by modelling the Ag film as exhibiting the bulk Ag transport properties.
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Affiliation(s)
- J W Wells
- Institute for Storage Ring Facilities and Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark
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Schreuer J, Wiehl L, Biehler J, Hofmann P. Crystal structure of tetrakis( μ-betaine-O,O')dibromo-dicopper(II) tetrabromocuprate( II) monohydrate, [Cu2{(CH3)3NCH2COO}4Br2][CuBr4]·H2O, with a propeller-shaped dinuclear copper complex. Z KRIST-NEW CRYST ST 2006. [DOI: 10.1524/ncrs.2006.0185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Wells JW, Kallehauge JF, Hansen TM, Hofmann P. Disentangling surface, bulk, and space-charge-layer conductivity in Si(111)-(7 x 7). Phys Rev Lett 2006; 97:206803. [PMID: 17155703 DOI: 10.1103/physrevlett.97.206803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2006] [Indexed: 05/12/2023]
Abstract
A novel approach for extracting genuine surface conductivities is presented and illustrated using the unresolved example of Si(111)-(7 x 7). Its temperature-dependent conductivity was measured with a microscopic four point probe between room temperature and 100 K. At room temperature the measured conductance corresponds to that expected from the bulk doping level. However, as the temperatures is lowered below approximately 200 K, the conductance decreases by several orders of magnitude in a small temperature range and it saturates at a low temperature value of approximately 4 x 10(-8) Omega(-1), irrespective of bulk doping. This abrupt transition is interpreted as the switching from bulk to surface conduction, an interpretation which is supported by a numerical model for the measured four point probe conductance. The value of the surface conductance is considerably lower than that of a good metal.
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Affiliation(s)
- J W Wells
- Institute for Storage Ring Facilities and Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark.
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Jürimäe J, Hofmann P, Jürimäe T, Mäestu J, Purge P, Wonisch M, Pokan R, von Duvillard SP. Plasma adiponectin response to sculling exercise at individual anaerobic threshold in college level male rowers. Int J Sports Med 2006; 27:272-7. [PMID: 16572368 DOI: 10.1055/s-2005-865661] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The purpose of the investigation was to study plasma adiponectin response to a single exercise session in male rowers. Eight college level, single scull rowers (VO2max: 5.01+/-0.43 l.min-1; age: 21.5+/-4.5 yrs; height: 184.9+/-5.0 cm; body mass: 78.5+/-8.4 kg; body fat: 11.8+/-1.2%) participated in this study. Venous blood samples were obtained before, immediately after, and following the first 30 min of recovery of constant load on-water rowing over a distance of 6.5 km (approximately 30 min) at the individual anaerobic threshold (75.2+/-2.9% of VO2max). Adiponectin was unchanged (p>0.05) immediately after the exercise. However, adiponectin was significantly increased above the resting value after the first 30 min of recovery (+14.7%; p<0.05). Similarly, leptin was unchanged immediately after exercise and was significantly decreased after the first 30 min of recovery (-18.2%; p<0.05). Plasma insulin was significantly reduced immediately after exercise and remained significantly lower during the first 30 min of recovery period. Glucose increased with exercise and returned to the pre-exercise level after the first 30 min of recovery. Basal adiponectin was significantly related to VO2max (r=-0.62; p=0.034). However, there was no relationship between basal adiponectin and other measured variables. Similarly, basal leptin demonstrated no relationship with other measured variables. In conclusion, the results of the present study suggest that plasma adiponectin is sensitive in the first 30 min of recovery to the effects of relatively short-term exercise at individual anaerobic threshold when all major muscle parts are involved.
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Affiliation(s)
- J Jürimäe
- Institute of Sport Pedagogy and Coaching Sciences, Centre of Behavioural and Health Sciences, University of Tartu, Tartu, Estonia.
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50
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Hofmann P, Friess P, Findeisen M, Tomcik P. [Case report of successful therapy of necrotizing fasciitis using a device of vacuum assisted closure]. Zentralbl Chir 2006; 131 Suppl 1:S72-4. [PMID: 16575649 DOI: 10.1055/s-2006-921475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Successful wound management is reported in a case of extended and life threatening necrotizing fasciitis of the leg of a poly-morbid older woman by use of standards of septic surgery (sufficient excision of necrotic tissue, use of bacteria adapted antibiotics, programmed wound revisions) and use of an industrial supplied device of vacuum assisted closure (V.A.C.).
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Affiliation(s)
- P Hofmann
- Kliniken Dr. Drogula GmbH, Neustadt bei Coburg.
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