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431.
A Shell‐Shaped Carbon Architecture with High‐Loading Capability for Lithium Sulfide Cathodes 下载免费PDF全文
Lithium sulfide (Li2S) is considered a highly attractive cathode for establishing high‐energy‐density rechargeable batteries, especially due to its high charge‐storage capacity and compatibility with lithium‐metal‐free anodes. Although various approaches have recently been pursued with Li2S to obtain high performance, formidable challenges still remain with cell design (e.g., low Li2S loading, insufficient Li2S content, and an excess electrolyte) to realize high areal, gravimetric, and volumetric capacities. This study demonstrates a shell‐shaped carbon architecture for holding pure Li2S, offering innovation in cell‐design parameters and gains in electrochemical characteristics. The Li2S core–carbon shell electrode encapsulates the redox products within the conductive shell so as to facilitate facile accessibility to electrons and ions. The fast redox‐reaction kinetics enables the cells to attain the highest Li2S loading of 8 mg cm?2 and the lowest electrolyte/Li2S ratio of 9/1, which is the best cell‐design specifications ever reported with Li2S cathodes so far. Benefiting from the excellent cell‐design criterion, the core–shell cathodes exhibit stable cyclability from slow to fast cycle rates and, for the first time, simultaneously achieve superior performance metrics with areal, gravimetric, and volumetric capacities. 相似文献
432.
433.
Effect of supplementation of recombinant Regucalcin in extender on cryopreservation of spermatozoa of water buffalo (Bubalus bubalis) 下载免费PDF全文
434.
Khadar Syed Musthafa Sunil Kumar Sahu Arumugam Veera Ravi Kandasamy Kathiresan 《World journal of microbiology & biotechnology》2013,29(10):1851-1858
The present study was carried out to assess the anti-quorum sensing (anti-QS) activity of bark extract obtained from the mangrove plant Rhizophora annamalayana Kathir. against Gram-negative bacteria. In microtitre plate assay, the bark extract at a concentration of 1 mg/ml inhibited the QS-dependent violacein production in Chromobacterium violaceum ATCC 12472. Further, the QS-dependent bioluminescence production in the aquatic bacterial pathogen Vibrio harveyi MTCC 3438 was also reduced to the level of 99 % when treated with the same concentration of the extract. Gas chromatography–mass spectrum analysis identified the presence of seven different chemical constituents, 1H-purin-6-amine, cycloheptasiloxane, cyclooctasiloxane, cyclononasiloxane, cyclononasiloxane octadecamethyl, cyclodecasiloxane eicosamethyl and 1,1,1,5,7,7,7-heptamethyl-3,3-bis(trimethylsiloxy)tetrasiloxane. The molecular docking analysis of the identified compounds revealed that the compounds cyclononasiloxane octadecamethyl and cyclodecasiloxane eicosamethyl exhibited the best docking energy with the QS receptors of C. violaceum and V. harveyi with that of the natural ligand N -hexanoyl- l -homoserine lactone (C6-HSL) and furanosyl borate diester (AI-2). Similarly, another compound 1,1,1,5,7,7,7-heptamethyl-3,3-bis(trimethylsiloxy)tetrasiloxane showed best docking energy only against C6-HSL. Thus, the results of the present study divulge the activity of R. annamalayana bark extract to interfere with bacterial QS. 相似文献
435.
Tang SC Arumugam TV Cutler RG Jo DG Magnus T Chan SL Mughal MR Telljohann RS Nassar M Ouyang X Calderan A Ruzza P Guiotto A Mattson MP 《Journal of neurochemistry》2007,101(3):729-736
Histidine is a naturally occurring amino acid with antioxidant properties, which is present in low amounts in tissues throughout the body. We recently synthesized and characterized histidine analogues related to the natural dipeptide carnosine, which selectively scavenge the toxic lipid peroxidation product 4-hydroxynonenal (HNE). We now report that the histidine analogue histidyl hydrazide is effective in reducing brain damage and improving functional outcome in a mouse model of focal ischemic stroke when administered intravenously at a dose of 20 mg/kg, either 30 min before or 60 min and 3 h after the onset of middle cerebral artery occlusion. The histidine analogue also protected cultured rat primary neurons against death induced by HNE, chemical hypoxia, glucose deprivation, and combined oxygen and glucose deprivation. The histidine analogue prevented neuronal apoptosis as indicated by decreased production of cleaved caspase-3 protein. These findings suggest a therapeutic potential for HNE-scavenging histidine analogues in the treatment of stroke and related neurodegenerative conditions. 相似文献
436.
437.
John Thundyil Silvia Manzanero Dale Pavlovski Tanya R. Cully Ker-Zhing Lok Alexander Widiapradja Prasad Chunduri Dong-Gyu Jo Chie Naruse Masahide Asano Bradley S. Launikonis Christopher G. Sobey Mark G. Coulthard Thiruma V. Arumugam 《PloS one》2013,8(1)
Ephrin (Eph) signaling within the central nervous system is known to modulate axon guidance, synaptic plasticity, and to promote long-term potentiation. We investigated the potential involvement of EphA2 receptors in ischemic stroke-induced brain inflammation in a mouse model of focal stroke. Cerebral ischemia was induced in male C57Bl6/J wild-type (WT) and EphA2-deficient (EphA2−/−) mice by middle cerebral artery occlusion (MCAO; 60 min), followed by reperfusion (24 or 72 h). Brain infarction was measured using triphenyltetrazolium chloride staining. Neurological deficit scores and brain infarct volumes were significantly less in EphA2−/− mice compared with WT controls. This protection by EphA2 deletion was associated with a comparative decrease in brain edema, blood-brain barrier damage, MMP-9 expression and leukocyte infiltration, and higher expression levels of the tight junction protein, zona occludens-1. Moreover, EphA2−/− brains had significantly lower levels of the pro-apoptotic proteins, cleaved caspase-3 and BAX, and higher levels of the anti-apoptotic protein, Bcl-2 as compared to WT group. We confirmed that isolated WT cortical neurons express the EphA2 receptor and its ligands (ephrin-A1–A3). Furthermore, expression of all four proteins was increased in WT primary cortical neurons following 24 h of glucose deprivation, and in the brains of WT mice following stroke. Glucose deprivation induced less cell death in primary neurons from EphA2−/− compared with WT mice. In conclusion, our data provide the first evidence that the EphA2 receptor directly contributes to blood-brain barrier damage and neuronal death following ischemic stroke. 相似文献
438.
439.
The effect of strain rate on the stress-strain behaviour of skin is studied. It is observed that the plastic set in the skin
is dependent on strain rate. The scanning electron micrographs of the fractured skin sample shows thicker fibrils and thinner
one at low strain rates. The plastic flow is clearly brought out in the stress-strain curves at different strain rates. The
stress relaxation behaviour at any given strain is clearly brought out in the 3-dimensional plot. 相似文献
440.
Ganesh Kumar Arumugam Sekaran Ganesan Swarnalatha Somasundaram Prasad Rao Burusa 《World journal of microbiology & biotechnology》2005,21(6-7):999-1007
Summary The solid resinous product (SRP) containing unsaturated/saturated dicarboxylic acid residues, phthalic acid and maleic acid
is discharged as a solid waste during cracking of benzene over vanadium at temperatures above 500°C in the dicarboxylic acid
manufacturing industry. In the present study the solid waste was diluted with water to a concentration of 0.5% w/v for microbial
degradation. The waste was fermented in a reactor containing mesoporous activated carbon on which was immobilized Saccharomyces cerevisiae at an optimum residence time of 24 h at pH 6.5. The immobilized-yeast-treated samples were further treated in an upflow anaerobic
reactor at an hydraulic retention time (HRT) of 0.1038 days at a hydraulic flow rate of 7.34 × 10−3 m3/day and chemical oxygen demand (COD) loading rate of 2.19 kg/m3/day. The pathway followed in the degradation of dicarboxylic acid into end products by anaerobic metabolism in the yeast
cell fermentor and in the upflow anaerobic reactor was confirmed through HPLC, Fourier transform infra red spectroscopy and
proton and 13C NMR spectroscopy. 相似文献