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61.
Torsten Bronger Paul H. Wöbkenberg Jan Wördenweber Stefan Muthmann Ulrich W. Paetzold Vladimir Smirnov Stephan Traut Ümit Dagkaldiran Stephan Wieber Michael Cölle Anna Prodi‐Schwab Odo Wunnicke Matthias Patz Martin Trocha Uwe Rau Reinhard Carius 《Liver Transplantation》2014,4(11)
Solution‐based semiconductors give rise to the next generation of thin‐film electronics. Solution‐based silicon as a starting material is of particular interest because of its favorable properties, which are already vastly used in conventional electronics. Here, the application of a silicon precursor based on neopentasilane for the preparation of thin‐film solar cells is reported for the first time, and, for the first time, a performance similar to conventional fabrication methods is demonstrated. Because three different functional layers, n‐type contact layer, intrinsic absorber, and p‐type contact layer, have to be stacked on top of each other, such a device is a very demanding benchmark test of performance of solution‐based semiconductors. Complete amorphous silicon n‐i‐p solar cells with an efficiency of 3.5% are demonstrated, which significantly exceeds previously reported values. 相似文献
62.
Lucas J. Gursky Jasmina Nikodinovic-Runic K. Anton Feenstra Kevin E. O’Connor 《Applied microbiology and biotechnology》2010,85(4):995-1004
The styAB genes from Pseudomonas putida CA-3, which encode styrene monooxygenase, were subjected to three rounds of in vitro evolution using error-prone polymerase
chain reaction with a view to improving the rate of styrene oxide and indene oxide formation. Improvements in styrene monooxygenase
activity were monitored using an indole to indigo conversion assay. Each round of random mutagenesis generated variants improved
in indigo formation with third round variants improved nine- to 12-fold over the wild type enzyme. Each round of in vitro
evolution resulted in two to three amino acid substitutions in styrene monooxygenase. While the majority of mutations occurred
in styA (oxygenase), mutations were also observed in styB (reductase). A mutation resulting in the substitution of valine with isoleucine at amino acid residue 303 occurred near the
styrene and flavin adenine dinucleotide binding site of styrene monooxygenase. One mutation caused a shift in the reading
frame in styA and resulted in a StyA variant that is 19 amino acids longer than the wild-type protein. Whole cells expressing the best
styrene monooxygenase variants (round 3) exhibited eight- and 12-fold improvements in styrene and indene oxidation rates compared
to the wild-type enzyme. In all cases, a single enantiomer, (S)-styrene oxide, was formed from styrene while (1S,2R)-indene oxide was the predominant enantiomer (e.e. 97%) formed from indene. The average yield of styrene oxide and indene oxide from their respective alkene substrates was
65% and 90%, respectively. 相似文献
63.
Verhoeven WM Feenstra I Van Ravenswaay-Arts C Egger JI Van Beurden JJ Tuinier S 《Genetic counseling (Geneva, Switzerland)》2006,17(3):307-313
The 18q deletion syndrome can be caused by several terminal and interstitial deletions of which terminal deletions of the distal part of 18q are the most frequent and known as the DeCroughy syndrome. The neuropsychiatric phenotype is not well documented and includes disorganised and disinhibited behaviours as well as language difficulties. Non development of language seems to be specific for cases with a more proximally located interstitial deletions. In the present paper a 18-year-old severely mentally retarded male with an interstitial deletion of 18q is described (46.XY,del(18)(q12.1q22.1) who was referred for behavioural problems and neuropsychiatric evaluation. No categorical psychiatric diagnosis could be established. Given this and other reports, it is advocated to describe the psychopathological phenotype of 18q deletions in a dimensional way that will result in a clinical picture characterised mainly by symptoms from the motor and motivation domains. Treatment should include primarily behavioural measures, combined if necessary with symptomatic psychopharmacotherapy. 相似文献
64.
Daphnia revisited: local stability and bifurcation theory for physiologically structured population models explained by way of an example 总被引:1,自引:0,他引:1
Odo Diekmann Mats Gyllenberg J. A. J. Metz Shinji Nakaoka Andre M. de Roos 《Journal of mathematical biology》2010,61(2):277-318
We consider the interaction between a general size-structured consumer population and an unstructured resource. We show that
stability properties and bifurcation phenomena can be understood in terms of solutions of a system of two delay equations
(a renewal equation for the consumer population birth rate coupled to a delay differential equation for the resource concentration).
As many results for such systems are available (Diekmann et al. in SIAM J Math Anal 39:1023–1069, 2007), we can draw rigorous
conclusions concerning dynamical behaviour from an analysis of a characteristic equation. We derive the characteristic equation
for a fairly general class of population models, including those based on the Kooijman–Metz Daphnia model (Kooijman and Metz in Ecotox Env Saf 8:254–274, 1984; de Roos et al. in J Math Biol 28:609–643, 1990) and a model introduced
by Gurney–Nisbet (Theor Popul Biol 28:150–180, 1985) and Jones et al. (J Math Anal Appl 135:354–368, 1988), and next obtain
various ecological insights by analytical or numerical studies of special cases. 相似文献
65.
Aditi Bagchi Zachary Madaj Kelly B. Engel Ping Guan Daniel C. Rohrer Dana R. Valley Emily Wolfrum Kristin Feenstra Nancy Roche Galen Hostetter Helen M. Moore Scott D. Jewell 《The journal of histochemistry and cytochemistry》2021,69(5):297
Analysis of formalin-fixed paraffin-embedded (FFPE) tissue by immunohistochemistry (IHC) is commonplace in clinical and research laboratories. However, reports suggest that IHC results can be compromised by biospecimen preanalytical factors. The National Cancer Institute’s Biospecimen Preanalytical Variables Program conducted a systematic study to examine the potential effects of delay to fixation (DTF) and time in fixative (TIF) on IHC using 24 cancer biomarkers. Differences in IHC staining, relative to controls with a DTF of 1 hr, were observed in FFPE kidney tumor specimens after a DTF of ≥2 hr. Reductions in H-score and/or staining intensity were observed for c-MET, p53, PAX2, PAX8, pAKT, and survivin, whereas increases were observed for RCC1, EGFR, and CD10. Prolonged TIF of 72 hr resulted in significantly reduced H-scores of CD44 and c-Met in kidney tumor specimens, compared with controls with 12-hr TIF. An elevated probability of altered staining intensity due to DTF was observed for nine antigens, whereas for prolonged TIF an elevated probability was observed for one antigen. Results reported here and elsewhere across tumor types and antigens support limiting DTF to ≤1 hr when possible and fixing tissues in formalin for 12–24 hr to avoid confounding effects of these preanalytical factors on IHC. 相似文献
66.
Fode P Larsen AR Feenstra B Jespersgaard C Skov RL Stegger M Fowler VG;Danish SAB Study Group Consortium Andersen PS 《PloS one》2012,7(2):e32315
Introduction
Human beta-defensins are key components of human innate immunity to a variety of pathogens, including Staphylococcus aureus. The aim of the present study was to investigate a potential association between gene variations in DEFB1 and DEFB103/DEFB4 and the development of S. aureus bacteremia (SAB) employing a case-control design.Methods
Cases were unique patients with documented SAB, identified with the National S. aureus Bacteremia Register, a comprehensive dataset of all episodes of community associated-SABs (CA-SAB) occurring in children (≤20 yrs) in Denmark from 1990 to 2006. Controls were age-matched healthy individuals with no history of SAB. DNA obtained from cases and controls using the Danish Newborn Screening Biobank were genotyped for functional polymorphisms of DEFB1 by Sanger sequencing and copy number variation of the DEFB103 and DEFB4 genes using Pyrosequencing-based Paralogue Ratio Test (P-PRT).Results
193 ethnic Danish SAB cases with 382 age-matched controls were used for this study. S. aureus isolates represented a variety of bacterial (i.e., different spa types) types similar to SAB isolates in general. DEFB1 minor allele frequencies of rs11362 (cases vs. controls 0.47/0.44), rs1800972 (0.21/0.24), and rs1799946 (0.32/0.33) were not significantly different in cases compared with controls. Also, DEFB4/DEFB103 gene copy numbers (means 4.83/4.92) were not significantly different in cases compared with controls.Conclusions
Using a large, unique cohort of pediatric CA-SAB, we found no significant association between DEFB1 genetic variation or DEFB4/DEFB103 gene copy number and susceptibility for SAB. 相似文献67.
Leenaars CH Kalsbeek A Hanegraaf MA Foppen E Joosten RN Post G Dematteis M Feenstra MG van Someren EJ 《Chronobiology international》2012,29(3):344-355
Exposure to shiftwork has been associated with multiple health disorders and cognitive impairments in humans. We tested if we could replicate metabolic and cognitive consequences of shiftwork, as reported in humans, in a rat model comparable to 5 wks of non-rotating night shifts. The following hypotheses were addressed: (i) shiftwork enhances body-weight gain, which would indicate metabolic effects; and (ii) shiftwork negatively affects learning of a simple goal-directed behavior, i.e., the association of lever pressing with food reward (instrumental learning), which would indicate cognitive effects. We used a novel method of forced locomotion to model work during the animals' normal resting period. We first show that Wistar rats, indeed, are active throughout a shiftwork protocol. In contrast with previous findings, the shiftwork protocol attenuated the normal weight gain to 76 ± 8 g in 5 wks as compared to 123 ± 15 g in the control group. The discrepancy with previous work may be explained by the concurrent observation that with our shiftwork protocol rats did not adjust their between-work circadian activity pattern. They maintained a normal level of activity during the "off-work" periods. In the control experiment, rats were kept active during the dark period, normally dominated by activity. This demonstrated that forced activity, per se, did not affect body-weight gain (mean ± SEM: 85 ± 11 g over 5 wks as compared to 84 ± 11 g in the control group). Rats were trained on an instrumental learning paradigm during the fifth week of the protocol. All groups showed equivalent increases in lever pressing from the first (3.8 ± .7) to the sixth (21.3 ± 2.4) session, and needed a similar amount of sessions (5.1 ± .3) to reach a learning criterion (≥ 27 out of 30 lever presses). These results suggest that while on prolonged non-rotating shiftwork, not fully reversing the circadian rhythm might actually be beneficial to prevent body-weight gain and cognitive impairments. 相似文献
68.
69.
David P. Rotella Geraldine R. McFarlane Alexander Greenfield Cristina Grosanu Albert J. Robichaud Rajiah Aldrin Denny Rolf W. Feenstra Sara Núñez-García Jan-Hendrik Reinders Martina van der Neut Andrew McCreary Chris G. Kruse Kelly Sullivan Farhana Pruthi Margaret Lai Jean Zhang Dianne M. Kowal Tikva Carrick Steven M. Grauer Rachel L. Navarra Mark H. Pausch 《Bioorganic & medicinal chemistry letters》2009,19(19):5552-5555
A 5-fluoro-tetrahydrocarbazole serotonin reuptake inhibitor (SRI) building block was combined with a variety of linkers and dopamine D2 receptor ligands in an attempt to identify potent D2 partial agonist/SRI molecules for treatment of schizophrenia. This approach has the potential to treat a broader range of symptoms compared to existing therapies. Selected compounds in this series demonstrate high affinity for both targets and D2 partial agonism in cell-based and in vivo assays. 相似文献
70.
MOTIVATION: Membrane-bound proteins are a special class of proteins. The regions that insert into the cell-membrane have a profoundly different hydrophobicity pattern compared with soluble proteins. Multiple alignment techniques use scoring schemes tailored for sequences of soluble proteins and are therefore in principle not optimal to align membrane-bound proteins. RESULTS: Transmembrane (TM) regions in protein sequences can be reliably recognized using state-of-the-art sequence prediction techniques. Furthermore, membrane-specific scoring matrices are available. We have developed a new alignment method, called PRALINETM, which integrates these two features to enhance multiple sequence alignment. We tested our algorithm on the TM alignment benchmark set by Bahr et al. (2001), and showed that the quality of TM alignments can be significantly improved compared with the quality produced by a standard multiple alignment technique. The results clearly indicate that the incorporation of these new elements into current state-of-the-art alignment methods is crucial for optimizing the alignment of TM proteins. AVAILABILITY: A webserver is available at http://www.ibi.vu.nl/programs/pralinewww. 相似文献