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91.
Peter James Carrington Abu Syed Mahajumi Magnus C. Wagener Johannes Reinhardt Botha Qian Zhuang Anthony Krier 《Physica B: Condensed Matter》2012,407(10):1493-1496
We report on the fabrication of GaAs based p–i–n solar cells containing 5 and 10 layers of type II GaSb quantum rings grown by molecular beam epitaxy. Solar cells containing quantum rings show improved efficiency at longer wavelengths into the near-IR extending up to 1500 nm and show enhanced short-circuit current under 1 sun illumination compared to a GaAs control cell. A reduction in the open-circuit voltage is observed due to the build-up of internal strain. The MBE growth, formation and photoluminescence of single and stacked layers of GaSb/GaAs quantum rings are also presented. 相似文献
92.
Junghans P Schrader G Faust H Wagner B Hirschberg K Reinhardt R 《Isotopes in environmental and health studies》2012,48(2):208-225
During the 29th Soviet Antarctic Expedition in Novolazarevskaya from March 1984 to March 1985, the protein and energy metabolisms were studied in six expeditioners from the German Democratic Republic. The investigations were carried out at the beginning of the expedition (May), during the polar night (July) and during the polar day (December). The effect of a special stress situation (sledge trek in April 1984) was investigated in one subject. The stable nitrogen isotope (15)N was used to study the protein metabolism. The assessment of the energy metabolism was based on the oxygen consumption, which was determined by means of a spirograph. In addition, the vital capacity, the breath minute volume, the blood pressure, etc. were measured. The following results were obtained: During the polar night, the utilisation of the dietary proteins and the whole body protein synthesis calculated by means of the (15)N excretion of the total nitrogen in urine were greater (73.6±0.9 % and 3.48±0.17?g protein d(-1)?kg(-1), n=3) than the respective values during the polar day (69.7±1.2, p<0.05, n=3 and 3.05±0.07, p<0.05, n=3) and at the beginning of the expedition (69.6±1.4, p<0.02, n=5 and 2.81±0.09, p<0.01, n=5). The lowest values (58.0 % and 2.43?g protein d(-1)?kg(-1)) were obtained in the subject after the trek. The resting metabolic rate (in kJ?d(-1)?m(-2)) was decreased during the polar night (45.6±5.0, n=4) in comparison with the polar day (61.5±11.3, n=3) and the beginning of the expedition (52.3±9.6, n=4) with p<0.01 in both cases. 相似文献
93.
Viviane M. Oliveira Barrichelo Reinhardt J. Heuer Carole M. Dean Robert T. Sataloff 《Journal of voice》2001,15(3):344-350
Many studies have described and analyzed the singer's formant. A similar phenomenon produced by trained speakers led some authors to examine the speaker's ring. If we consider these phenomena as resonance effects associated with vocal tract adjustments and training, can we hypothesize that trained singers can carry over their singing formant ability into speech, also obtaining a speaker's ring? Can we find similar differences for energy distribution in continuous speech? Forty classically trained singers and forty untrained normal speakers performed an all-voiced reading task and produced a sample of a sustained spoken vowel /a/. The singers were also requested to perform a sustained sung vowel /a/ at a comfortable pitch. The reading was analyzed by the long-term average spectrum (LTAS) method. The sustained vowels were analyzed through power spectrum analysis. The data suggest that singers show more energy concentration in the singer's formant/speaker's ring region in both sung and spoken vowels. The singers' spoken vowel energy in the speaker's ring area was found to be significantly larger than that of the untrained speakers. The LTAS showed similar findings suggesting that those differences also occur in continuous speech. This finding supports the value of further research on the effect of singing training on the resonance of the speaking voice. 相似文献
94.
Laryngeal Myasthenia Gravis: Report of 40 Cases 总被引:4,自引:0,他引:4
Vivian H. Mao Mona Abaza Joseph R. Spiegel Steven Mandel Mary Hawkshaw Reinhardt J. Heuer Robert T. Sataloff 《Journal of voice》2001,15(1):122-130
Myasthenia gravis, an autoimmune disorder of the neuromuscular junction, is usually recognized because of ocular complaints or generalized weakness. We report a series of 40 patients who presented with dysphonia as their initial and primary complaint. Diagnostic testing included strobovideolaryngoscopy, electromyography (EMG) with repetitive stimulation and Tensilon testing, and laboratory and radiographic evaluation. Strobovideolaryngoscopy most commonly revealed fluctuating impairment of vocal fold mobility, either unilateral or bilateral. EMG detected evidence of neuromuscular junction abnormalities in all patients. Only one patient had evidence of antiacetylcholine receptor (ACh-R) antibodies, but many other abnormalities suggestive of autoimmune dysfunction were present. Pyridostigmine therapy was initiated in 34 patients but was not tolerated in 4. Of the remaining 30 patients, 23 reported improvement of symptoms. We conclude that myasthenia gravis can present with symptoms confined primarily to the larynx and should be included in the differential diagnosis of dysphonia. 相似文献
95.
Amy M. Zimmermann-Klemd Jakob K. Reinhardt Moritz Winker Carsten Gründemann 《Molecules (Basel, Switzerland)》2022,27(10)
Modern phytotherapy is part of today’s conventional evidence-based medicine and the use of phytopharmaceuticals in integrative oncology is becoming increasingly popular. Approximately 40% of users of such phytopharmaceuticals are tumour patients. The present review provides an overview of the most important plants and nature-based compounds used in integrative oncology and illustrates their pharmacological potential in preclinical and clinical settings. A selection of promising anti-tumour plants and ingredients was made on the basis of scientific evidence and therapeutic practical relevance and included Boswellia, gingko, ginseng, ginger, and curcumin. In addition to these nominees, there is a large number of other interesting plants and plant ingredients that can be considered for the treatment of cancer diseases or for the treatment of tumour or tumour therapy-associated symptoms. Side effects and interactions are included in the discussion. However, with the regular and intended use of phytopharmaceuticals, the occurrence of adverse side effects is rather rare. Overall, the use of defined phytopharmaceuticals is recommended in the context of a rational integrative oncology approach. 相似文献
96.
Zuo Hang Yu Christopher J. Reinhardt Thomas Hin-Fung Wong Ka Yan Tong Prof. Jefferson Chan Dr. Ho Yu Au-Yeung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(40):8794-8800
Ascorbate is an important biological reductant and enzyme cofactor. Although direct detection through ascorbate-mediated reduction is possible, this approach suffers from poor selectivity due to the wide range of cellular reducing agents. To overcome this limitation, we leverage reduction potential of ascorbate to mediate a copper-mediated oxidative bond cleavage of ether-caged fluorophores. The copper(II) complexes supported by a {bis(2-pyridylmethyl)}benzylamine or a {bis(2-pyridylmethyl)}(2-methoxybenzyl)amine ligand were identified as an ascorbate responsive unit and their reaction with ascorbate yields a copper-based oxidant that enables rapid benzylic oxidation and the release of an ether-caged dye (coumarin or fluorescein). The copper-mediated bond cleavage is specific to ascorbate and the trigger can be readily derivatized for tuning photophysical properties of the probes. The probes were successfully applied for the fluorometric detection of ascorbate in commercial food samples, human plasma, and serum, and within live cells by using confocal microscopy and flow cytometry. 相似文献
97.
C. Kippenberger F. Fischer C. Reinhardt J. Coquillion J. F. Willard G. Neumann H. Drehschmidt Klas Sondén Wilhelm Thörner W. Mac Farlone P. Caldwell R. Namias Binder W. E. Adeney W. Younger Vivian B. Lewes T. Lonatscheffsky-Petruniaka Maurice Meslans M. Arndt G. Pfeiffer Sigmund Neumann A. Lwoff F. Cowes S. B. Redwood S. Waters Murdy J. A. Wanklyn W. J. Cooper L. L. de Koninck und G. Linossier 《Fresenius' Journal of Analytical Chemistry》1896,35(1):184-200
Ohne Zusammenfassung 相似文献
98.
The kinetics for the electrode reactions with oxygen and with NO and NO2 in the presence of oxygen has been studied for La0.8Sr0.2MnO3±δ-electrodes on stabilized zirconia (8 mol% Y2O3=YSZ) in the temperature range between 500°C and 900°C for oxygen partial pressures between 1 kPa and 20 kPa by means of electrochemical
methods (impedance, I-U characteristics) and temperature programmed desorption (TPD). For oxygen reduction below 900°C a mechanism
is proposed which describes the formation of peroxidic ions at the electrode surface and a subsequent rate-determining electron
transfer at the three-phase-boundary. At temperatures below 650°C the electrode reaction between NO and NO2 is much faster than the oxygen reduction. The results for the NO2-reduction to NO can be explained by a two-step mechanism consisting of a fast one-electron transfer to adsorbed NO2 at the electrode surface and a subsequent rate-determining transfer of the second electron to NO2 at the three-phase-boundary.
Paper presented at the 1st Euroconference on Solid State Ionics, Zakynthos, Greece, 11 – 18 Sept. 1994 相似文献
99.
C. Reinhardt und Jul Schenkel 《Fresenius' Journal of Analytical Chemistry》1890,29(1):184-185
Ohne Zusammenfassung 相似文献
100.