Observation of Seven Astrophysical Tau Neutrino Candidates with IceCube

We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.

Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

Evidence for neutrino emission from the nearby active galaxy NGC 1068

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy’s active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of 79 − 20 + 22 neutrinos at tera–electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera–electron volt gamma rays from this source.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9}  eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

Migration of iodine-129 and iodine-127 in soils

To draw the balance of anthropogenic 129I input into European soils, the concentrations of 129I and 127I in seven soils from Lower Saxony were analyzed down to a depth of 250 cm. In comparison with pre-nuclear soils and Ukrainian soils, we detected a significant anthropogenic input of 129I. Considering the different time periods for the input of 129I and 127I it was possible to assess the dynamics of sorption processes which dominate migration and accumulation. Anthropogenic 129I was successfully used as a tracer for a clarification of the migration processes of trace elements in soils.

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

AB0796 THE EVALUATION OF LUNG DIAGNOSTIC PROCEDURE AT THE ONSET OF INFLAMMATORY RHEUMATIC DISEASES WITH INTERSTITIAL LUNG DISEASE

Background:

Interstitial lung disease (ILD) in inflammatory rheumatic diseases (IRD) is associated with increased mortality. Moreover, the lung is one of the most effected organs on IRD. Consequently, screening methods were required to the detect ILD in IRD.

Objectives:

The objective of the following study is to evaluate the diagnostic value of lung function test, chest x-ray and HR-CT of the lung in the detection of ILD at the onset of IRD.

Methods:

The study is designed as a case-control study and includes 126 patients with a newly diagnosed IRD. It was matched by gender, age and the performance of lung function test and chest x-ray. The sensitivity and specificity were verified by crosstabs and receiver operating characteristic (ROC) curve analysis. The study cohort was divided in two groups (ILD group: n = 63 and control group: n = 63). If possible, all patients received a lung function test and optional a chest x-ray. Patients with pathological findings in the screening tests (chest x-ray or reduced diffusing capacity for carbon monoxide (DLCO) < 80 %) maintained a high-resolution computer tomography (HR-CT) of the lung. Additionally, an immunological bronchioalveolar lavage was performed in the ILD group as gold standard for the detection of ILD.

Results:

The DLCO (< 80 %) revealed a sensitivity of 83.6 % and specificity of 45.8 % for the detection of ILD. Other examined parameter of lung function test showed no sufficient sensitivity as screening test (FVC = Forced Vital Capacity, FEV1 = Forced Expiratory Volume in 1 second, TLC = Total Lung Capacity, TLCO = Transfer factor of the Lung for carbon monoxide). Also, a combination of different parameter did not increase the sensitivity. The sensitivity and specificity of chest x-ray for the verification of ILD was 64.2 % versus 73.6 %. The combination of DLCO (< 80 %) and chest x-ray showed a sensitivity with 95.2 % and specificity with 38.7 %. The highest sensitivity (95.2 %) and specificity (77.4 %) was observed for the combination of DLCO (< 80 %) and HR-CT of the lung.

Conclusion:

The study highlighted that a reduced DLCO in lung function test is associated with a lung involvement in IRD. DLCO represented a potential screening parameter for lung manifestation in IRD. Especially patients with suspected vasculitis should receive an additional chest x-ray. Based on the high sensitivity of DLCO in combination with chest x-ray or HR-CT for the detection of ILD in IRD, all patients with a reduced DLCO (< 80%) should obtained an imaging of the lung.

Disclosure of Interests:

None declared

Advanced Gel Permeation Chromatography system with increased loading capacity: Polycyclic aromatic hydrocarbons detection in olive oil as a case of study

Gel permeation chromatography (GPC) is herein used as size exclusion clean-up technique for highly sensitive and straightforward detection of Polycyclic Aromatic Hydrocarbons (PAHs) in olive oil samples. An advanced chromatographic system has been developed to isolate a series of PAHs with cancerogenic potential, including PAH4 (benzo(a)pyrene BaP, benzo(a)anthracene BaA, benzo(b)fluoranthene BbF and chrysene Chry) reported in the European Regulation. The system avails of two glass chromatographic columns and a switching valve, that allow removal of interfering analytes in olive oil without resorting to any preliminary extraction process. A seven-fold increase of the loaded sample amount versus conventional chromatographic systems (1 g vs 0.150 g) has been pursued, as well as improved PAHs detection and quantification limits (LOD-LOQ for PAH4: 0.21-0.70 ng/g for BaA, 0.26-0.86 ng/g for Chry, 0.23-0.76 ng/g for BbF, 0.32-1.06 ng/g for BaP), in accordance with the continuous need of more and more reducing these limits in food analysis by the European Regulation. The protocol developed represents a highly innovative and efficient analytical method for organic pollutants in complex biological matrices as olive oil, that can have huge impact on technology for PAHs detection in food samples, being suitable for both industrial and small-scale laboratories.

eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100  eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5  eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

Excess mortality due to COVID-19 in Germany

OBJECTIVES

The first wave of the SARS-CoV-2 pandemic in Germany lasted from week 10 to 23 in 2020. The aim is to provide estimates of excess mortality in Germany during this time.

METHODS

We analyzed age-specific numbers of deaths per week from 2016 to week 26 in 2020. We used weekly mean numbers of deaths of 2016-2019 to estimate expected weekly numbers for 2020. We estimated standardized mortality ratios (SMR) and 95% confidence intervals.

RESULTS

During the first wave observed numbers of deaths were higher than expected for age groups 60-69, 80-89, and 90+. The age group 70-79 years did not show excess mortality. The net excess number of deaths for weeks 10-23 was +8,071. The overall SMR was 1•03 (95%CI 1•03-1•04). The largest increase occurred among people aged 80-89 and 90+ (SMR=1•08 and SMR=1•09). A sensitivity analysis that accounts for demographic changes revealed an overall SMR of 0•98 (95%CI 0•98-0•99) and a deficit of 4,926 deaths for week 10-23, 2020.

CONCLUSIONS

The excess mortality existed for two months. The favorable course of the first wave may be explained by a younger age at infection at the beginning of the pandemic, lower contact rates, and a more efficient pandemic management.

Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100  TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100  TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100  TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

Psychological support in times of COVID-19: the Essen community-based CoPE concept

The SARS CoV-2-virus (COVID-19) pandemic is pushing national and international structures to their limits. Little is known about treatment options to combat the novel virus, but the same applies to the effects of COVID-19 on people’s mental health. In Germany, as in many other countries, governmental actions impact peoples’ individual freedom. These highly necessary actions to slow down the spread of the virus, however, are a burden to the community. We established a structured concept to support psychological burdened people in Essen, which is located in the Ruhr area, a metropolitan region with more than 5.1 million inhabitants in the heart of the federal state North Rhine Westphalia. The psychological burden following the spread of the virus and individual restrictions should not be neglected.

AB0822 WHICH CLINICAL FACTORS INFLUENCE MINERALIZATION OF THE METACARPAL BONES AND FINGER JOINT SPACE WIDTH IN PSORIATIC ARTHRITIS?

Background:

Metacarpal bone mineral density as measured by digital x-ray radiogrammetry (DXR-BMD) and finger joint space width quantified by computer-aided joint space analysis presented computer based and observer independent parameters for the evaluation of radiographic damage of the hand skeleton.

Objectives:

The aim of this study was to quantify clinical parameter which potential influence periarticular mineralisation of the metacarpal bones and finger joint space width in Psoriatic Arthritis (PsA)-patients.

Methods:

The study includes 201 PsA-patients. All patients received a radiograph of the hand. Bone mineral density was measured by DXR (Pronosco X-Posure System™, Version 2.0; Sectra; Sweden) and finger joint space width of all finger joints were evaluated by computer-aided joint space analysis (CAJSA, Radiogrammetry Kit, Version 1.3.6; Sectra; Sweden). The Z-Score was used as an age- and gender-independent parameter for the quantification finger joint space narrowing.

Results:

Regarding gender, the DXR-BMD was significant reduced with -0.028 g/cm2in women. An equivalent significant result was evaluated for finger joint space width (Z-ScoreMCP -1.07, Z-ScorePIP -0.81 and Z-ScoreDIP -0.76). The DXR-BMD was significantly lowert (-0.011 g/cm2) between the disease duration < 2 years (0.545±0.076 g/cm2) and >10 years (0.509±0.070 g/cm2). The Z-Score showed no significant change regarding the disease duration. Inflammatory activity as measured by c-reactive protein presented no impact on DXR-BMD and the Z-Score of all finger joints. Additionally, the use of corticosteroids was associated with a reduced DXR-BMD (-0.037 g/cm2) and an absence of finger joint space narrowing.

Conclusion:

The study highlights that the demineralisation of the metacarpal bones was associated with female gender, disease duration and the use of corticosteroids. Whereas, the prior mentioned parameters had no influence on finger joint space width. Consequently, periarticular demineralisation and finger joint space narrowing presented two different and independent radiological signs in PsA.

References:

N/A

Disclosure of Interests:

Alexander Pfeil Grant/research support from: This study Investigator Initiated Study “Automatic assessment of joint space narrowing in rheumatoid arthritis based on the Post-hoc analysis” (number: IIS-2016-110818) is a part of the of the Investigator Initiated Study “The quantification of inflammatory related periarticular bone loss in certolizumab pegol treated patients with rheumatoid arthritis” (number: IIS-2014-101458) which is supported by UCB Pharma GmbH, Monheim, Germany., Marcus Heinz: None declared, Diane Renz: None declared, Joachim Böttcher: None declared, Gunter Wolf: None declared, Peter Oelzner: None declared

THU0146 DAS28-REMISSION IS ASSOCIATED WITH AN INCREASE OF FINGER JOINT SPACE WIDTH IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

The reduction of finger joint space width in patients with rheumatoid arthritis (RA) is associated with joint destruction. Anti-TNF treatment with certolizumab pegol is an effective therapy in RA-patients. The computer-assisted joint space analysis is a new computer based technique to measure joint space width on hand radiographs.

Objectives:

The aim of this post-hoc analysis of the data set used in the RAPID 1 trial was to quantify finger joint space width of RA patients treated with Certolizumab pegol in Association to DAS28-remission.

Methods:

The post-hoc analysis includes 297 patients. These patients were treated with certolizumab pegol 200 mg (every two weeks) plus methotrexate and certolizumab pegol 400 mg (every two weeks) plus methotrexate. All patients underwent x-rays of the hand at baseline and week 52 as well as the quantification of finger joint space width of the metacarpal-phalangeal articulations (MCP) using the computer-assisted joint space analysis (Version 1.3.6; Sectra; Sweden). The joint space distance is expressed as mean joint space width of the MCP joints I to V (JSD-MCP total). Remission was defined with a Disease Activity Score 28 < 2.6.

Results:

The group with DAS28-remission (DAS28 < 2.6) presented a significant joint space increase with 3.3 % for JSD-MCP total from 0.152 ± 0.033 cm (baseline) to 0.157 ± 0.033 cm (week 52) treated with certolizumab pegol 200 mg as well as with 3.9 % for JSD-MCP total from 0.152 ± 0.031 cm (baseline) to 0.158 ± 0.032 cm (week 52). For the patients without DAS28-remission (DAS28 > 2.6) under the treatment with certolizumab pegol 400 mg a non-significant change of JSD-MCP total from 0.145 ± 0.034 cm (baseline) to 0.144 ± 0.036 cm (week 52) was observed. A similar result was evaluated for the certolizumab pegol 200 mg group (JSD-MCP total: 0.146 ± 0.037 cm [baseline] to 0.143 ± 0.037 cm [week 52]).

Conclusion:

The study highlights that patients treated with certolizumab pegol plus methotrexat and a DAS-Remission showed an increase of joint space width of the metacarpal-phalangeal articulations which is potentially associated with reparative effects of the cartilage under the anti-TNF treatment with certolizumab pegol.

References:

N/A

Disclosure of Interests:

Alexander Pfeil Grant/research support from: This study Investigator Initiated Study “Automatic assessment of joint space narrowing in rheumatoid arthritis based on the Post-hoc analysis” (number: IIS-2016-110818) is a part of the of the Investigator Initiated Study “The quantification of inflammatory related periarticular bone loss in certolizumab pegol treated patients with rheumatoid arthritis” (number: IIS-2014-101458) which is supported by UCB Pharma GmbH, Monheim, Germany., Anica Nussbaum: None declared, Diane Renz: None declared, Ansgar Malich: None declared, Joachim Böttcher: None declared, Peter Oelzner: None declared, Gunter Wolf: None declared

Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1  TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

[Analysis of referral diagnoses to the rheumatology department]

BACKGROUND

The initial presentation of patients with symptoms indicative of a rheumatic disease is in most cases not directly to a rheumatologist. This study evaluated the following questions: I. Which medical specialists refer patients to a department of rheumatology? II. Evaluation of the accordance of the presumptive referral diagnosis and the final diagnosis by a rheumatologist.

METHODS

A total of 947 patients (279 men and 668 women) who initially presented to a university hospital for rheumatological diagnostics were included in the study. The referring medical specialist fields were identified. Furthermore, a kappa analysis was performed to evaluate the accordance of the presumptive referral diagnosis and the final diagnosis generated after a rheumatological evaluation of the patients.

RESULTS

Of the referrals 73% were initiated by general practitioners or internists functioning as general practitioners. The other referrers were 5% specialists in internal medicine (excluding rheumatology), 4% orthopedic/trauma surgeons, 1% other surgeons and 4% other specialist fields. A rheumatological diagnosis was made in 58% of the patients and rheumatological inflammatory joint diseases (26%), collagenosis (14%) and vasculitides (5%) were the most frequently diagnoses. The accordance of the presumptive diagnosis of the general practitioners and the final diagnosis after rheumatological evaluation was a kappa coefficient of κ = 0.304. Lower kappa values were evaluated for orthopedic surgeons (κ = 0.277) and other specialists (κ = 0.200).

CONCLUSION

The referrals to a rheumatology institution were frequently initiated by general practitioners and internists functioning as general practitioners. In this context the presumptive diagnosis of general practitioners showed a low accordance with the final rheumatological diagnosis. In contrast, a detailed presumptive diagnosis is desirable for optimal use of the limited resources for rheumatological care.

MRI of cystic fibrosis lung manifestations: sequence evaluation and clinical outcome analysis

AIM

To evaluate different magnetic resonance imaging (MRI) sequences for diagnosis of pulmonary manifestations of cystic fibrosis (CF) in comparison to chest computed tomography (CT), including an extended outcome analysis.

MATERIALS AND METHODS

Twenty-eight patients with CF (15 male, 13 female, mean age 30.5±9.4 years) underwent CT and MRI of the lung. MRI (1.5 T) included different T2- and T1-weighted sequences: breath-hold HASTE (half Fourier acquisition single shot turbo spin echo) and VIBE (volumetric interpolated breath-hold examination, before and after contrast medium administration) sequences and respiratory-triggered PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) sequences with and without fat signal suppression, and perfusion imaging. CT and MRI images were evaluated by the modified Helbich and the Eichinger scoring systems. The clinical follow-up analysis assessed pulmonary exacerbations within 24 months.

RESULTS

The highest concordance to CT was achieved for the PROPELLER sequences without fat signal suppression (concordance correlation coefficient CCC of the overall modified Helbich score 0.93 and of the overall Eichinger score 0.93). The other sequences had the following concordance: PROPELLER with fat signal suppression (CCCs 0.91 and 0.92), HASTE (CCCs 0.87 and 0.89), VIBE (CCCs 0.84 and 0.85) sequences. In the outcome analysis, the combined MRI analysis of all five sequences and a specific MRI protocol (PROPELLER without fast signal suppression, VIBE sequences, perfusion imaging) reached similar correlations to the number of pulmonary exacerbations as the CT examinations.

CONCLUSION

An optimum lung MRI protocol in patients with CF consists of PROPELLER sequences without fat signal suppression, VIBE sequences, and lung perfusion analysis to enable high diagnostic efficacy and outcome prediction.

Observation of the universal magnetoelectric effect in a 3D topological insulator

The electrodynamics of topological insulators (TIs) is described by modified Maxwell's equations, which contain additional terms that couple an electric field to a magnetization and a magnetic field to a polarization of the medium, such that the coupling coefficient is quantized in odd multiples of α/4π per surface. Here we report on the observation of this so-called topological magnetoelectric effect. We use monochromatic terahertz (THz) spectroscopy of TI structures equipped with a semitransparent gate to selectively address surface states. In high external magnetic fields, we observe a universal Faraday rotation angle equal to the fine structure constant α=e2/2hc (in SI units) when a linearly polarized THz radiation of a certain frequency passes through the two surfaces of a strained HgTe 3D TI. These experiments give insight into axion electrodynamics of TIs and may potentially be used for a metrological definition of the three basic physical constants.

Application of groundwater thresholds for trace elements on percolation water: a case study on percolation water from Northern German lowlands

The German insignificance thresholds (GFS) for groundwater, derived with an added risk approach, will soon be adopted as trigger values for percolation water entering groundwater. The physicochemical properties of the vadose zone differ considerably from those of groundwater, which may lead to difficulties in the applicability of groundwater-derived GFS to percolation water. To test the applicability of the GFS to percolation water regarding the concentration level and the field-scale variability, 46 sites in Northern Germany were sampled, including arable land, grassland, and forest, situated on three spatially dominant parent materials: sand, glacial loam, and loess. Concentrations of As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Sn, V, Zn, and F were analyzed in percolation water from the transition between the unsaturated to the saturated zone. We compared median and 90th percentile values of the background concentrations with the GFS. In more than 10% of all samples, background concentrations of Cd, Co, Ni, V, or Zn exceeded the GFS. We evaluated the applicability of the GFS on field-scale medians of background concentrations taking field-scale interquartile distance and the bootstrap percentile confidence interval of the field scale median of trace element background concentrations into consideration. Statements about exceedance or nonexceedance of GFS values could only be made with acceptable statistical uncertainty (α ≤ 0.1) when operational median concentrations were about one third higher or lower than the corresponding GFS.

New insights into peripartum cardiomyopathy using cardiac magnetic resonance imaging

PURPOSE

The aim of this study was to evaluate a comprehensive cardiac magnetic resonance (MR) imaging approach in patients with peripartum cardiomyopathy (PPCM). The focus was on inflammatory myocardial changes.

MATERIALS AND METHODS

Retrospective analysis of 12 cardiac MR examinations was performed in 6 patients with PPCM. The protocol comprised cine sequences for the determination of chamber sizes and function. T 2-weighted sequences for determination of edema (T 2 ratio), T 1-weighted images for measurement of early gadolinium enhancement ratio (EGER), and late gadolinium enhancement (LGE) sequences were used for tissue characterization. 5 examinations were performed during the acute stage, and 7 examinations were performed during the course of the disease.

RESULTS

Initially, 3 of 5 patients presented with an elevated left ventricular end-diastolic volume (LVEDV); in one patient, the LVEDV was in the upper range. In 4 of 5 subjects, the left ventricular ejection fraction (LVEF) was decreased. The T 2 ratio and EGER values were initially elevated in all women. No LGE was detected in initial scans. In follow-up examinations, the LVEDV decreased and the LVEF increased in all patients. Tissue-characterizing parameters decreased to normal in all but 1 patient. 2 patients showing LGE did not present a favorable clinical course.

CONCLUSION

Myocardial inflammation was detected in the acute stage of PPCM, which was mostly transient. In our small group, patients showing LGE had a non-favorable clinical course. Future studies should include tissue-characterizing parameters, such as T 2 ratio and EGER. Thus, further insights into pathophysiology can be gained and therapeutic effects can be measured in a more extensive manner.

Diffusion-weighted imaging of hyperacute cerebral hypoglycemia

BACKGROUND AND PURPOSE

Cerebral hypoglycemia can result in reversible metabolic brain insults and can be associated with impaired diffusion disturbances. Our aim was to evaluate possible changes in DWI of the human brain during hyperacute short-term severe hypoglycemia.

MATERIALS AND METHODS

Ten individuals scheduled for a clinical IST were examined with DWI while the test was performed. Venous blood glucose was continuously measured, and sequential DWI sequences were performed without interruption. Hypoglycemia was terminated with intravenous glucose administration when glucose levels were at ≤2.0 mmol/L.

RESULTS

Blood glucose levels were lowered to a mean nadir of 1.75 ± 0.38 mmol/L. No alterations of cerebral diffusion could be observed in any individuals on DWI.

CONCLUSIONS

Hyperacute short-term severe hypoglycemia does not induce visible changes in DWI of the human brain.

The structure of CDK8/CycC implicates specificity in the CDK/cyclin family and reveals interaction with a deep pocket binder

Cyclin-dependent kinase (CDK) 8 associates with cyclin C (CycC) and belongs to the CDK module of the Mediator of transcription, together with MED12 and MED13. CDK8 is involved in the regulation of mRNA transcription and was identified as a potent oncogene in colon cancerogenesis. We have solved the 2.2-Å crystal structure of CDK8/CycC in complex with sorafenib, an anti-cancer drug of clinical relevance. The CDK8 structure reveals a unique CycC recognition helix that explains the specificity of the CDK8/CycC pair and discrimination among the highly promiscuous binding in the CDK/cyclin family. In contrast to all CDKs, the CDK8 activation loop appears not to be phosphorylated. Based on the structure, we discuss an alternate mode of CDK8 activation to the general CDK activation by T-loop phosphorylation. Sorafenib binds to the catalytic cleft of CDK8. It displays a deep pocket binding mode and is the first small molecule to induce a DFG-out conformation in the CDK family, which is actually DMG-out in CDK8.

Next generation 1.5 microm terahertz antennas: mesa-structuring of InGaAs/InAlAs photoconductive layers

Mesa-structuring of InGaAs/InAlAs photoconductive layers is performed employing a chemical assisted ion beam etching (CAIBE) process. Terahertz photoconductive antennas for 1.5 microm operation are fabricated and evaluated in a time domain spectrometer. Order-of-magnitude improvements versus planar antennas are demonstrated in terms of emitter power, dark current and receiver sensitivity.