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51.
Solar Cells: Ionic Liquid Control Crystal Growth to Enhance Planar Perovskite Solar Cells Efficiency (Adv. Energy Mater. 20/2016)
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52.
A potential interaction between the local hemodynamics and the artery wall response has been suggested for vascular graft failure by intimal hyperplasia (IH). Among the various hemodynamic factors, wall shear stress has been implicated as the primary factor responsible for the development of IH. In order to explore the role of hemodynamics in the formation of IH in end-to-side anastomosis, computational fluid dynamics is employed. To validate the numerical simulations, comparisons with existing experimental data are performed for both steady and pulsatile flows. Generally, good agreement is observed with the velocity profiles whereas some discrepancies are found in wall shear stress (WSS) distributions. Using the same end-to-side anastomosis geometry, numerical simulations are extended using a femoral artery waveform to identify the possible role of unsteady hemodynamics. In the current simulations, Carreau-Yasuda model is used to account for the non-Newtonian nature of blood. Computations indicated a disturbed flow field at the artery-graft junction leading to locally elevated shear stresses on the vascular wall. Furthermore, the shear stress distribution followed the same behavior with oscillating magnitude over the entire flow cycle. Thus, distal IH observed in end-to-side artery-graft models may be caused by the fluctuations in WSS's along the wall. 相似文献
53.
Basha SJ Naveed SA Tiwari NK Shashikumar D Muzeeb S Kumar TR Kumar NV Rao NP Srinivas N Mullangi R Srinivas NR 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,853(1-2):88-96
Simultaneous separation and quantification of ezetimibe (EZM) and its phase-I metabolite i.e., ezetimibe ketone (EZM-K) and phase-II metabolite i.e., ezetimibe glucuronide (EZM-G) in various matrices was accomplished by gradient HPLC with UV detection. The assay procedure involved deproteinization of 500 microL of either incubation or bile sample containing analytes and internal standard (IS, theophylline) with 75 microL acetonitrile containing 25% perchloric acid. An aliquot of 100 microL supernatant was injected onto a C18 column. The chromatographic separation was achieved by gradient elution consisting of 0.05 M formic acid:acetonitrile:methanol:water at a flow rate of 1.0 mL/min. The detection of analyte peaks were achieved by monitoring the eluate using an UV detector set at 250 nm. Nominal retention times of IS, EZM-G, ezetimibe ketone glucuronide (EZM-KG), EZM and EZM-K were 9.39, 24.23, 27.82, 29.04 and 30.56 min, respectively. Average extraction efficiencies of EZM, EZM-G and IS was >75-80% and for EZM-K was >50% from all the matrices tested. Limit of quantitation (LOQ) for EZM, EZM-K and EZM-G was 0.02 microg/mL. Due to the lack of availability of reference standard of EZM-KG, the recovery and LOQ aspects for this metabolite were not assessed. Overall, the method is suitable for simultaneous measurement of EZM, and its phase-I and phase-II metabolite (EZM-G) in in vitro and in vivo studies. 相似文献
54.
Background
This paper presents a unified framework for finding differentially expressed genes (DEGs) from the microarray data. The proposed framework has three interrelated modules: (i) gene ranking, ii) significance analysis of genes and (iii) validation. The first module uses two gene selection algorithms, namely, a) two-way clustering and b) combined adaptive ranking to rank the genes. The second module converts the gene ranks into p-values using an R-test and fuses the two sets of p-values using the Fisher's omnibus criterion. The DEGs are selected using the FDR analysis. The third module performs three fold validations of the obtained DEGs. The robustness of the proposed unified framework in gene selection is first illustrated using false discovery rate analysis. In addition, the clustering-based validation of the DEGs is performed by employing an adaptive subspace-based clustering algorithm on the training and the test datasets. Finally, a projection-based visualization is performed to validate the DEGs obtained using the unified framework. 相似文献55.
56.
Sudheer Pamidimarri DV Singh S Mastan SG Patel J Reddy MP 《Molecular biology reports》2009,36(6):1357-1364
Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel,
is emerging as an alternative to petro-diesel. The deoiled seed cake remains after oil extraction is toxic and cannot be used
as a feed despite having best nutritional contents. No quantitative and qualitative differences were observed between toxic
and non-toxic varieties of J. curcas except for phorbol esters content. Development of molecular marker will enable to differentiate non-toxic from toxic variety
in a mixed population and also help in improvement of the species through marker assisted breeding programs. The present investigation
was undertaken to characterize the toxic and non-toxic varieties at molecular level and to develop PCR based molecular markers
for distinguishing non-toxic from toxic or vice versa. The polymorphic markers were successfully identified specific to non-toxic
and toxic variety using RAPD and AFLP techniques. Totally 371 RAPD, 1,442 AFLP markers were analyzed and 56 (15.09%) RAPD,
238 (16.49%) AFLP markers were found specific to either of the varieties. Genetic similarity between non-toxic and toxic verity
was found to be 0.92 by RAPD and 0.90 by AFLP fingerprinting. In the present study out of 12 microsatellite markers analyzed,
seven markers were found polymorphic. Among these seven, jcms21 showed homozygous allele in the toxic variety. The study demonstrated
that both RAPD and AFLP techniques were equally competitive in identifying polymorphic markers and differentiating both the
varieties of J. curcas. Polymorphism of SSR markers prevailed between the varieties of J. curcas. These RAPD and AFLP identified markers will help in selective cultivation of specific variety and along with SSRs these
markers can be exploited for further improvement of the species through breeding and Marker Assisted Selection (MAS). 相似文献
57.
Gangishetti U Breitenbach S Zander M Saheb SK Müller U Schwarz H Moussian B 《European journal of cell biology》2009,88(3):167-180
Chitin is an essential constituent of the insect exoskeleton, the cuticle, which is an extracellular matrix (ECM) covering the animal. It is produced by the glycosyltransferase chitin synthase at the apical plasma membrane of epidermal and tracheal cells. To fulfil its role in cuticle elasticity and stiffness it associates with proteins, thereby adopting a stereotypic arrangement of helicoidally stacked sheets, which run parallel to the surface of the animal. One approach to understand the mechanisms of chitin synthesis and organisation is to dissect these processes genetically. However, since only a few genes coding for factors involved in chitin synthesis and organisation have been identified to date using the model arthropod Drosophila melanogaster insight arising from mutant analysis is rather limited. To collect new data on the role of chitin during insect cuticle differentiation, we have analysed the effects of chitin synthesis inhibitors on Drosophila embryogenesis. For this purpose, we have chosen the benzoylphenylurea diflubenzuron and lufenuron that are widely used as insect growth regulators. Our data allow mainly two important conclusions. First, correct organisation of chitin seems to directly depend on the amount of chitin synthesised. Second, chitin synthesis and organisation are cell-autonomous processes as insecticide-treated larvae display a mosaic of cuticle defects. As benzoylphenylurea are used not only as insecticides but also as anti-diabetic drugs, the study of their impact on Drosophila cuticle differentiation may be fruitful for understanding their mode of action on a cellular pathway that is seemingly conserved between vertebrates and invertebrates. 相似文献
58.
Manganese(II) complexes, Mn2L13(ClO4)4, MnL1(H2O)2(ClO4)2, MnL2(H2O)2(ClO4)2, and {(μ-Cl)MnL2(PF6)}2 based on N,N′-bis(2-pyridinylmethylene) ethanediamine (L1) and N,N′-bis(2-pyridinylmethylene) propanediamine (L2) ligands have been prepared and characterized. The single crystal X-ray diffraction analysis of Mn2L23(ClO4)4 shows that each of the two Mn(II) ion centers with a Mn-Mn distance of 7.15 Å are coordinated by one ligand while a common third ligand bridges the metal centers. Solid-state magnetic susceptibility measurements as well as DFT calculations confirm that each of the manganese centers is high-spin S = 5/2. The electronic structure obtained shows no orbital overlap between the Mn(II) centers indicating that the observed weak antiferromagentism is a result of through space interactions between the two Mn(II) centers. Under different reaction conditions, L1 and Mn(II) yielded a one-dimensional polymer, MnL1(H2O)2(ClO4)2. Ligand L2 when reacted with manganese(II) perchlorate gives contrarily to L1 mononuclear MnL2(H2O)2(ClO4)2 complex. The analysis of the structural properties of the MnL2(H2O)2(ClO4)2 lead to the design of dinuclear complex {(μ-Cl)MnL2(PF6)} where two chlorine atoms were utilized as bridging moieties. This complex has a rhomboidal Mn2Cl2 core with a Mn-Mn distance of 3.726 Å. At room temperature {(μ-Cl)MnL2(PF6)} is ferromagnetic with observed μeff = 4.04 μB per Mn(II) ion. With cooling, μeff grows reaching 4.81 μB per Mn(II) ion at 8 K, and then undergoes ferromagnetic-to-antiferromagnetic phase transition. 相似文献
59.
The present work deals with the biosorption performance of raw and chemically modified biomass of the brown seaweed Lobophora variegata for removal of Cd(II) and Pb(II) from aqueous solution. The biosorption capacity was significantly altered by pH of the solution
delineating that the higher the pH, the higher the Cd(II) and Pb(II) removal. Kinetic and isotherm experiments were carried
out at the optimal pH 5.0. The metal removal rates were conspicuously rapid wherein 90% of the total sorption occurred within
90 min. Biomass treated with CaCl2 demonstrated the highest potential for the sorption of the metal ions with the maximum uptake capacities i.e. 1.71 and 1.79 mmol g−1 for Cd(II) and Pb(II), respectively. Kinetic data were satisfactorily manifested by a pseudo-second order chemical sorption
process. The process mechanism consisting of both surface adsorption and pore diffusion was found to be complex. The sorption
data have been analyzed and fitted to sorption isotherm of the Freundlich, Langmuir, and Redlich–Peterson models. The regression
coefficient for both Langmuir and Redlich–Peterson isotherms were higher than those secured for Freundlich isotherm implying
that the biosorption system is possibly monolayer coverage of the L. variegata surface by the cadmium and lead ions. FT-IR studies revealed that Cd(II) and Pb(II) binding to L. variegata occurred primarily through biomass carboxyl groups accompanied by momentous interactions of the biomass amino and amide groups.
In this study, we have observed that L. variegata had maximum biosorption capacity for Cd(II) and Pb(II) reported so far for any marine algae.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
60.
Jhillu Singh Yadav Kamani Satyanarayana Pamu Sreedhar Pabbaraja Srihari Thokhir Basha Shaik Shasi Vardhan Kalivendi 《Bioorganic & medicinal chemistry letters》2010,20(12):3814-3817
The racemic total synthesis of elegansidiol, farnesiferol B, and farnesiferol D has been obtained following a Diels–Alder approach. Gillman addition, cross metathesis reaction are the other key steps involved in the target synthesis. 相似文献