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Melendez LV, Nguyen CK, Wilms M, Syed N, Daeneke T, Duffy NW, Fery A, Della Gaspera E, Gómez DE. Probing the Interaction between Individual Metal Nanocrystals and Two-Dimensional Metal Oxides via Electron Energy Loss Spectroscopy. Nano Lett 2024; 24:1944-1950. [PMID: 38305174 DOI: 10.1021/acs.nanolett.3c04225] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Metal nanoparticles can photosensitize two-dimensional metal oxides, facilitating their electrical connection to devices and enhancing their abilities in catalysis and sensing. In this study, we investigated how individual silver nanoparticles interact with two-dimensional tin oxide and antimony-doped indium oxide using electron energy loss spectroscopy (EELS). The measurement of the spectral line width of the longitudinal plasmon resonance of the nanoparticles in absence and presence of 2D materials allowed us to quantify the contribution of chemical interface damping to the line width. Our analysis reveals that a stronger interaction (damping) occurs with 2D antimony-doped indium oxide due to its highly homogeneous surface. The results of this study offer new insight into the interaction between metal nanoparticles and 2D materials.
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Affiliation(s)
- Lesly V Melendez
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Chung Kim Nguyen
- School of Engineering, RMIT University, Melbourne, Victoria 3000, Australia
| | - Michael Wilms
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
| | - Nitu Syed
- School of Engineering, RMIT University, Melbourne, Victoria 3000, Australia
- School of Physics, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Torben Daeneke
- School of Engineering, RMIT University, Melbourne, Victoria 3000, Australia
| | - Noel W Duffy
- CSIRO Energy, Clayton South, Victoria 3169, Australia
| | - Andreas Fery
- Physical Chemistry of Polymeric Materials, Technische Universität Dresden, Bergstr. 66, 01069 Dresden, Germany
- Institute for Physical Chemistry and Polymer Physics, Leibniz Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany
| | | | - Daniel E Gómez
- School of Science, RMIT University, Melbourne, Victoria 3000, Australia
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Wilms M, Melendez LV, Hudson RJ, Hall CR, Ratnayake SP, Smith T, Della Gaspera E, Bryant G, Connell TU, Gomez D. Photoinitiated Energy Transfer in Porous-Cage-Stabilised Silver Nanoparticles. Angew Chem Int Ed Engl 2023:e202303501. [PMID: 37186332 DOI: 10.1002/anie.202303501] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 05/17/2023]
Abstract
We report a new composite material consisting of silver nanoparticles decorated with three-dimensional molecular organic cages based on light absorbing porphyrins. The porphyrin cages serve to both stabilize the particles and allow diffusion and trapping of small molecules close to the metallic surface. Combining these two photoactive components results in a Fano resonant interaction between the porphyrin Soret band and the nanoparticle localised surface plasmon resonance. Time resolved spectroscopy revealed the silver nanoparticles transfer up to 37% of their excited state energy to the stabilising layer of porphyrin cages. These unusual photophysics cause a 2-fold current increase in photoelectrochemical water splitting measurements. The composite structure provides a compelling proof-of-concept for advanced photosensitiser systems with intrinsic porosity for photocatalytic and sensing applications.
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Affiliation(s)
| | | | - Rohan J Hudson
- The University of Melbourne, School of Chemistry, AUSTRALIA
| | | | | | - Trevor Smith
- The University of Melbourne, School of Chemistry, AUSTRALIA
| | | | - Gary Bryant
- RMIT University, School of Science, AUSTRALIA
| | - Timothy U Connell
- Deakin University, School of Life and Environmental Science, AUSTRALIA
| | - Daniel Gomez
- RMIT University, Chemistry, Melbourne, 3000, Melbourne, AUSTRALIA
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Wilms M, Lövey G, Wilms M, Wetzig S, Stephanou M, Shaheen M, Kolberg-Liedtke C, Hadji P, Kolberg HC. MRI guided high-focused ultrasound (MRgFUS) as treatment for symptomatic uterine fibroids – experiences of 339 cases. Geburtshilfe Frauenheilkd 2020. [DOI: 10.1055/s-0040-1718102] [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: 10/23/2022] Open
Affiliation(s)
- M Wilms
- Marienhospital Wesel, Klinik für Kardiologie, Angiologie und Pneumologie
| | | | | | | | | | | | | | - P Hadji
- Frankfurter Hormon und Osteoporosezentrum
- Philipps Universität Marburg
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Shepherd W, Wilms M, van Embden J, Della Gaspera E. Accurate control of stoichiometry and doping in barium stannate perovskite oxide nanoparticles. Chem Commun (Camb) 2019; 55:11880-11883. [PMID: 31528881 DOI: 10.1039/c9cc04838c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Barium stannate (BaSnO3) is one of the most promising emerging materials for use as a transparent electrode. However, to date, its synthesis has been proven to be highly irreproducible. In this communication, we present a detailed investigation of the reproducibility issues and provide a robust approach to synthesize BaSnO3 nanomaterials with controlled stoichiometry and doping.
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Affiliation(s)
- William Shepherd
- School of Science, RMIT University, Melbourne, VIC 3000, Australia.
| | - Michael Wilms
- School of Science, RMIT University, Melbourne, VIC 3000, Australia.
| | - Joel van Embden
- School of Science, RMIT University, Melbourne, VIC 3000, Australia.
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Sothmann T, Gauer T, Wilms M, Werner R. Correspondence model-based 4D VMAT dose simulation for analysis of local metastasis recurrence after extracranial SBRT. ACTA ACUST UNITED AC 2017; 62:9001-9017. [DOI: 10.1088/1361-6560/aa955b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Ortmüller J, Gauer T, Wilms M, Handels H, Werner R. Respiratory surface motion measurement by Microsoft Kinect. Current Directions in Biomedical Engineering 2015. [DOI: 10.1515/cdbme-2015-0067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
In radiotherapy of abdominal and thoracic tumors, respiratory motion is a problem for an accurate treatment. Most current motion compensation techniques rely on externally acquired breathing signals of the patient. The systems in clinical use usually work with 1D surface motion signals to describe internal structure respiratory motion patterns. As a 1D signal is not able to describe complex motion patterns and breathing variations, in this work the Microsoft Kinect, which can record multidimensional respiratory surface motion signals, is proposed to be used instead. For the Kinect, a clinically acceptable measurement setup is designed and Kinect measurements are compared to the Varian RPM system (clinical standard). The results show that the signals are well aligned. An additional comparison of Kinect signals from different regions of interest on the chest further reveals variations between them. This illustrates that the use of a system that provides multidimensional signals is worthwhile; the knowledge about breathing variations could be applied for optimization of current clinical workflows.
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Affiliation(s)
- J. Ortmüller
- Department of Radiotherapy and Radio-Oncology, University Medical Center Hamburg-Eppendorf, Institute of Medical Informatics, University of Lübeck
| | - T. Gauer
- Department of Radiotherapy and Radio-Oncology, University Medical Center Hamburg-Eppendorf
| | - M. Wilms
- Institute of Medical Informatics, University of Lübeck
| | - H. Handels
- Institute of Medical Informatics, University of Lübeck
| | - R. Werner
- Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf
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Müller J, Wilms M, Oberhoffer R. Acute Effects of Submaximal Endurance Training on Arterial Stiffness in Healthy Middle- and Long-Distance Runners. J Clin Hypertens (Greenwich) 2015; 17:371-4. [DOI: 10.1111/jch.12530] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/23/2015] [Accepted: 01/26/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Jan Müller
- Institute of Preventive Pediatrics; Technische Universität München; München Germany
| | - Michael Wilms
- Institute of Preventive Pediatrics; Technische Universität München; München Germany
| | - Renate Oberhoffer
- Institute of Preventive Pediatrics; Technische Universität München; München Germany
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Wilms M, Werner R, Blendowski M, Ortmüller J, Handels H. Simulation of range imaging-based estimation of respiratory lung motion. Influence of noise, signal dimensionality and sampling patterns. Methods Inf Med 2014; 53:257-63. [PMID: 24993030 DOI: 10.3414/me13-01-0137] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 04/18/2014] [Indexed: 12/25/2022]
Abstract
OBJECTIVES A major problem associated with the irradiation of thoracic and abdominal tumors is respiratory motion. In clinical practice, motion compensation approaches are frequently steered by low-dimensional breathing signals (e.g., spirometry) and patient-specific correspondence models, which are used to estimate the sought internal motion given a signal measurement. Recently, the use of multidimensional signals derived from range images of the moving skin surface has been proposed to better account for complex motion patterns. In this work, a simulation study is carried out to investigate the motion estimation accuracy of such multidimensional signals and the influence of noise, the signal dimensionality, and different sampling patterns (points, lines, regions). METHODS A diffeomorphic correspondence modeling framework is employed to relate multidimensional breathing signals derived from simulated range images to internal motion patterns represented by diffeomorphic non-linear transformations. Furthermore, an automatic approach for the selection of optimal signal combinations/patterns within this framework is presented. RESULTS This simulation study focuses on lung motion estimation and is based on 28 4D CT data sets. The results show that the use of multidimensional signals instead of one-dimensional signals significantly improves the motion estimation accuracy, which is, however, highly affected by noise. Only small differences exist between different multidimensional sampling patterns (lines and regions). Automatically determined optimal combinations of points and lines do not lead to accuracy improvements compared to results obtained by using all points or lines. CONCLUSIONS Our results show the potential of multidimensional breathing signals derived from range images for the model-based estimation of respiratory motion in radiation therapy.
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Affiliation(s)
- M Wilms
- Matthias Wilms, Institute of Medical Informatics, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany, E-mail:
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Wilms M, Werner R, Ehrhardt J, Schmidt-Richberg A, Schlemmer HP, Handels H. Multivariate regression approaches for surrogate-based diffeomorphic estimation of respiratory motion in radiation therapy. Phys Med Biol 2014; 59:1147-64. [PMID: 24557007 DOI: 10.1088/0031-9155/59/5/1147] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Breathing-induced location uncertainties of internal structures are still a relevant issue in the radiation therapy of thoracic and abdominal tumours. Motion compensation approaches like gating or tumour tracking are usually driven by low-dimensional breathing signals, which are acquired in real-time during the treatment. These signals are only surrogates of the internal motion of target structures and organs at risk, and, consequently, appropriate models are needed to establish correspondence between the acquired signals and the sought internal motion patterns. In this work, we present a diffeomorphic framework for correspondence modelling based on the Log-Euclidean framework and multivariate regression. Within the framework, we systematically compare standard and subspace regression approaches (principal component regression, partial least squares, canonical correlation analysis) for different types of common breathing signals (1D: spirometry, abdominal belt, diaphragm tracking; multi-dimensional: skin surface tracking). Experiments are based on 4D CT and 4D MRI data sets and cover intra- and inter-cycle as well as intra- and inter-session motion variations. Only small differences in internal motion estimation accuracy are observed between the 1D surrogates. Increasing the surrogate dimensionality, however, improved the accuracy significantly; this is shown for both 2D signals, which consist of a common 1D signal and its time derivative, and high-dimensional signals containing the motion of many skin surface points. Eventually, comparing the standard and subspace regression variants when applied to the high-dimensional breathing signals, only small differences in terms of motion estimation accuracy are found.
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Affiliation(s)
- M Wilms
- Institute of Medical Informatics, University of Lübeck, D-23538 Lübeck, Germany
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Theodoropoulos F, Hang H, Wilms M, Freitag L, Darwiche K. Erfolgreiche Kryorekanalisation einer Hauptbronchusstenose bei Totalatelektase der linken Lunge durch ein Lipom. Pneumologie 2013. [DOI: 10.1055/s-0033-1334584] [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: 10/27/2022]
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Kukolja J, Thiel C, Wilms M, Mirzazade S, Fink G. Altersabhängige Veränderungen neuronaler Netzwerke bei räumlichem Quellengedächtnis: Eine fMRT-Studie. Akt Neurol 2006. [DOI: 10.1055/s-2006-953126] [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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Vasilev K, Zhu T, Wilms M, Gillies G, Lieberwirth I, Mittler S, Knoll W, Kreiter M. Simple, one-step synthesis of gold nanowires in aqueous solution. Langmuir 2005; 21:12399-403. [PMID: 16343020 DOI: 10.1021/la052354f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A simple procedure to synthesize gold nanowires based on the reduction of hydrogen tetrachloroaurate by 2-mercaptosuccinic acid in aqueous solution is presented. This procedure requires no additional capping or reduction agent and produces wires with an apparent curly morphology several micrometers in length with diameters as thin as 15 nm. Some of the wires produced end in a ribbonlike structure, finally terminated by a flat triangular prism. Investigations by scanning electron microscopy, transmission electron microscopy (bright and dark field), scanning transmission electron microscopy, and atomic force microscopy as well as conductivity measurements indicate fully connected, polycrystalline gold objects.
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Affiliation(s)
- Krasimir Vasilev
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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Kordonouri O, Hartmann R, Deiss D, Wilms M, Grüters-Kieslich A. Natural course of autoimmune thyroiditis in type 1 diabetes: association with gender, age, diabetes duration, and puberty. Arch Dis Child 2005; 90:411-4. [PMID: 15781936 PMCID: PMC1720371 DOI: 10.1136/adc.2004.056424] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [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] [Indexed: 11/04/2022]
Abstract
AIMS To investigate the natural history and incidence of autoimmune thyroiditis (AIT) in paediatric patients with type 1 diabetes (T1D). METHODS Since 1990, annual screening for thyroid disease has been performed in children and adolescents with T1D. Antibodies against thyroperoxidase (anti-TPO) and thyroglobulin (anti-TG) as well as TSH were measured in 659 patients (54.3% boys). In 126 patients, anti-TPO and anti-TG levels were followed at yearly intervals from onset up to five years of T1D. Anti-TPO above 30 U/ml and anti-TG above 20 U/ml were considered positive, values above 100 U/ml as significantly raised and indicative of AIT. L-thyroxine treatment was started if TSH was higher than 4.5 microU/ml and/or thyroid gland enlargement on thyroid ultrasound was present. RESULTS At initial screening, 15.4% of patients had raised anti-TPO and 14.4% anti-TG. Girls had more frequently raised antibodies than boys. Sixty two patients (9.4%, 61% girls) required treatment with L-thyroxine. The cumulative incidence (SE) of AIT after 10 years of diabetes was 0.14 (0.02), being significantly higher in females (0.18 (0.03)), particularly after the age of 12 years. At T1D onset, positive anti-TPO and anti-TG were present in 21 of 126 patients (16.7%), each. All patients with significantly increased values of anti-TPO (n = 17, 148-5340 U/ml) and anti-TG (n = 11, 140-2000 U/ml) at T1D onset remained positive during the following five years. CONCLUSIONS For early detection of autoimmune thyroiditis in children with T1D, measurement of anti-TPO and TSH at T1D onset and in yearly intervals after the age of 12 years is recommended.
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Affiliation(s)
- O Kordonouri
- Clinic of General Pediatrics, Otto-Heubner-Centrum, Charité, Campus Virchow-Klinikum, Humboldt University, Berlin, Germany.
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Eckhorn R, Stett A, Schanze T, Gekeler F, Schwahn H, Zrenner E, Wilms M, Eger M, Hesse L. Physiologische Funktionsprüfungen von Retinaimplantaten an Tiermodellen. Ophthalmologe 2001; 98:369-75. [PMID: 11374278 DOI: 10.1007/s003470170143] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [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: 10/27/2022]
Abstract
Retinal implants can--by electrical stimulation--create visual impressions in people with certain kinds of degenerative retinal diseases (e.g. Retinitis Pigmentosa). Electrically evoked potentials in the retina must be transferred into the visual cortex in an orderly manner, a prerequisite for any kind of form- and movement-perception. In the current developmental stage the difficult investigations are performed in various animal models: isolated retinae of intact chicken and of RCS-rats (a model for Retinitis Pigmentosa), as well as in anesthetised rabbits, pigs and cats with intact retinae. Our investigations show that spatially selective ganglion-cell responses can be recorded following focal electrical stimulation, in healthy and as well in degenerated retinae. Registration of activities in area 17 of the visual cortex demonstrate that electrical retinal stimulation can indeed activate it.
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Affiliation(s)
- R Eckhorn
- Philipps-Universität Marburg, FB Physik, AG Neurophysik, Renthof 7, 35032 Marburg.
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Hesse L, Schanze T, Wilms M, Eger M. Implantation of retina stimulation electrodes and recording of electrical stimulation responses in the visual cortex of the cat. Graefes Arch Clin Exp Ophthalmol 2000; 238:840-5. [PMID: 11127571 DOI: 10.1007/s004170000197] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [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: 10/27/2022] Open
Abstract
BACKGROUND Simple basic visual perception may be restored by epiretinal electrical stimulation in patients that are blind due to photoreceptor loss. To stimulate ganglion cells, epiretinally flat platinum microelectrodes embedded in thin polyimide film were developed and tested in the cat. METHODS After removal of the lens and the vitreous body a thin microfilm electrode array was implanted through a corneoscleral incision in the cat eye (n = 4). In two eyes no further attempt was made to fixate the tip of the electrode, which was pressed onto the retinal surface due to the tension of the curved polyimide film. In two eyes the tip of the electrode was fixed with cyanoacrylate adhesive. The exterior part of the microelectrode film was directed under the skin towards the forehead which allowed fixation of the microplug to a head fixation bolt. Retinal stimulation experiments were performed within 1 week after implantation. Success of stimulation was assessed by recording neuronal activities from areas 17 and 18. Retinal microelectrodes were removed 2 weeks or longer after implantation. RESULTS Intraocular inflammation or retinal detachment were not observed after implantation of the microelectrode film. In two eyes the tip of the microelectrodes dislocated spontaneously within the first few days. The lowest threshold of electrical stimulation was 35 microA, corresponding to a charge transfer of 14 nC per phase. These values were ten times higher than those obtained by needle electrodes used in prior experiments. CONCLUSIONS Intraocular implanted flat microelectrodes made of platinum and polyimide were well tolerated. Because of the flat configuration of the microelectrodes higher stimulation thresholds than for needle electrodes were found, indicating insufficient contact to the retinal surface. An alternative shape and fixation technique is required to minimise electrodes' threshold of stimulation.
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Affiliation(s)
- L Hesse
- Department of Ophthalmology, Philipps University, Marburg, Germany.
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Kronholz HL, Wilms M, Schütz J, Willich N. Herzschrittmacher in der Strahlentherapie. BIOMED ENG-BIOMED TE 1993. [DOI: 10.1515/bmte.1993.38.s1.413] [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: 11/15/2022]
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Schüttler J, Stoeckel H, Wilms M, Schwilden H, Lauven PM. [Infusion model for etomidate (author's transl)]. Anaesthesist 1980; 29:662-6. [PMID: 7212249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
An intravenous infusion scheme was established in five healthy volunteers on the basis of pharmacokinetic analysis as described by J.G. Wagner. Concentrations of etomidate in plasma were measured by gas chromatography after solvent extraction. The monitoring of EEG background activity was used for the correlation to the pharmacodynamic effect. The minimal plasma level producing an hypnotic effect was about 0.3 microgram/ml) etomidate. An infusion model was developed for a therapeutic plasma concentration of 0.5 microgram/ml etomidate. An initial fast constant-rate infusion (8 mg/min) was followed by an infusion with 0.8 mg/min for the entire duration of the application. The measured plasma levels coincided fairly well with the predicted steady state plasma levels and were accompanied by a distinct hypnotic effect in all volunteers.
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Schüttler J, Wilms M, Lauven PM, Stoeckel H, Koenig A. [Pharmacokinetics of etomidate in man (author's transl)]. Anaesthesist 1980; 29:658-61. [PMID: 7212248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The pharmacokinetic behaviour of etomidate was investigated in 7 patients. A method for the analysis of etomidate is described using gas-liquid chromatography for separation and alkali flame ionization detection. The lower limit of detection for etomidate in plasma was 0.005 microgram/ml. The pharmacokinetic behaviour of etomidate after an intravenous bolus injection of 20 mg may be described in terms of an open two-compartment model. The plasma half-life of etomidate was in the alpha-phase about 3 minutes, the biological half-life of the beta-phase was about 70 minutes. The total volume of distribution was calculated at 165 litres. The total plasma clearance amounted to 1600 ml/min. These pharmacokinetic data were used to establish an intravenous infusion scheme for etomidate.
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Abstract
The photochemical reaction cycle of bacteriorhodopsin was investigated by means of flash photometric methods. Three different intermediates with absorption maxima at about 630 nm, 411 nm, and 646 nm could be detected. Kinetic data of the occurrence of these intermediates were obtained from isolated purple membrane in different mediums and from intact halobacteria. An activation energy of 14.1 +/- 0.4 kcal-mol-1 and of about 19 kcal-mol-1 for formation of bacteriorhodopsin 411 and of bacteriorhodopsin 565, resp., was calculated. pH-changes in the medium caused by the reaction cycle of bacteriorhodopsin were detected by use of the pH-indicator bromocresol green.
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Stieve H, Wilms M, Nöll G. Measurements on the pH dependence of metarhodopsin reactions in sonicated rod outer segments. Z Naturforsch C 1973; 28:600-2. [PMID: 4272301 DOI: 10.1515/znc-1973-9-1018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Abstract
The kinetics of rhodopsin photolysis in sonicated suspensions of rod outer segments (ROS), unsonicated ROS suspensions and rhodopsin detergent solutions were compared. No significant kinetic differences were detected ; however, the energy of activation for the metarhodopsin I to metarhodopsin II reaction was somewhat higher in sonicated ROS suspensions than in the unsonicated suspensions. While the sonicated preparations contained glycerol, it was not possible to show a chemical influence of glycerol on the reactions of the rhodopsin decay. An often assumed effect that the ROS outer membrane acts as a barrier toward diffusion of protons could not be confirmed.
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Wilms M. Friedrich Trendelenburg zum 70. Geburtstag. Dtsch Med Wochenschr 1914. [DOI: 10.1055/s-0029-1190434] [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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Wilms M. Otto Leichtenstern †. Dtsch Med Wochenschr 1900. [DOI: 10.1055/s-0029-1203777] [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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Wilms M. Forcirte Wärmebehandlung bei Gelenkerkrankungen mittels eines einfachen Wärmeapparates 1). Dtsch Med Wochenschr 1898. [DOI: 10.1055/s-0029-1204421] [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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Wilms M. Myiasis dermatosa oestrosa. Dtsch Med Wochenschr 1897. [DOI: 10.1055/s-0029-1205119] [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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