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121.
Sulfidation of NiMn‐Layered Double Hydroxides/Graphene Oxide Composites toward Supercapacitor Electrodes with Enhanced Performance 下载免费PDF全文
Supercapacitors can deliver high‐power density and long cycle stability, but the limited energy density due to poor electronic and ionic conductivity of the supercapacitor electrode has been a bottleneck in many applications. A strategy to prepare microflower‐like NiMn‐layered double hydroxides (LDH) with sulfidation is delineated to reduce the charge transfer resistance of supercapacitor electrode and realize faster reversible redox reactions with notably enhanced specific capacitance. The incorporation of graphite oxide (GO) in NiMn LDH during sulfidation leads to simultaneous reduction of GO with enhanced conductivity, lessened defects, and doping of S into the graphitic structure. Cycling stability of the sulfidized composite electrode is enhanced due to the alleviation of phase transformation during electrochemical cycling test. As a result, this sulfidation product of LDH/GO (or LDHGOS) can reach a high‐specific capacitance of 2246.63 F g?1 at a current density of 1 A g?1, and a capacitance of 1670.83 F g?1 is retained at a high‐current density of 10 A g?1, exhibiting an outstanding capacitance and rate performance. The cycling retention of the LDHGOS electrode is also extended to ≈ 67% after 1500 cycles compared to only ≈44% of the pristine NiMn LDH. 相似文献
122.
Jia-Xiang See Chandramathi Samudi Alireza Saeidi Nivedita Menon Leang-Chung Choh Jamuna Vadivelu Esaki M. Shankar 《PLoS neglected tropical diseases》2016,10(3)
BackgroundBurkholderia pseudomallei (B. pseudomallei), the causative agent of melioidosis, is a deadly pathogen endemic across parts of tropical South East Asia and Northern Australia. B. pseudomallei can remain latent within the intracellular compartment of the host cell over prolonged periods of time, and cause persistent disease leading to treatment difficulties. Understanding the immunological mechanisms behind persistent infection can result in improved treatment strategies in clinical melioidosis.MethodsTen-day LD50 was determined for the small-colony variant (SCV) and its parental wild-type (WT) via intranasal route in experimental BALB/c mice. Persistent B. pseudomallei infection was generated by administrating sub-lethal dose of the two strains based on previously determined LD50. After two months, peripheral blood mononuclear cells (PBMCs) and plasma were obtained to investigate host immune responses against persistent B. pseudomallei infection. Lungs, livers, and spleens were harvested and bacterial loads in these organs were determined.ResultsBased on the ten-day LD50, the SCV was ~20-fold less virulent than the WT. The SCV caused higher bacterial loads in spleens compared to its WT counterparts with persistent B. pseudomallei infection. We found that the CD4+ T-cell frequencies were decreased, and the expressions of PD-1, but not CTLA-4 were significantly increased on the CD4+ and CD8+ T cells of these mice. Notably, persistent infection with the SCV led to significantly higher levels of PD-1 than the WT B. pseudomallei. Plasma IFN-γ, IL-6, and IL-17A levels were elevated only in SCV-infected mice. In addition, skewed plasma Th1 and Th17 responses were observed in SCV-infected mice relative to WT-infected and uninfected mice.ConclusionB. pseudomallei appears to upregulate the expression of PD-1 on T cells to evade host immune responses, which likely facilitates bacterial persistence in the host. SCVs cause distinct pathology and immune responses in the host as compared to WT B. pseudomallei. 相似文献
123.
Identification of genetic variants in erythrocyte lysate by two-dimensional gel electrophoresis. 总被引:8,自引:4,他引:4
B B Rosenblum J V Neel S M Hanash J L Joseph N Yew 《American journal of human genetics》1984,36(3):601-612
Two-dimensional gel electrophoresis followed by silver-staining has been employed to study 27 red cell lysates for genetic variation. Forty-six polypeptides selected without respect to variability were considered suitable for scoring. Only 23 of the total of 1,242 polypeptides could not be scored unambiguously. Of the remaining 1,219 polypeptides, 38 exhibited the combination of a normal and a variant polypeptide. All variants were present in either the father or the mother of the subjects. The observed index of heterozygosity was 3.1% +/- 0.5%. 相似文献
124.
The development of the retina of the albino rat was studied after sectioning of the optic nerves on the 2nd postnatal day. The 2nd day represents a stage at which the retina shows only the ganglion cell layer clearly delineated from an undifferentiated mass. Section of optic nerves at this stage did not affect the subsequent retinal development. Both control and experimental eyes developed at the same pace. Some minor degrees of 'retardation' e.g. the sizes of outer segments, appeared to deviate in the experimental retinae. 相似文献
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The alkaline phosphatase and DNA-RNA activities in the retinas of young and old albino mice were determined histochemically after photic exposure. Different patterns between the two age groups were obtained for the alkaline phosphatase reaction before and after photic exposure. In the young animals, more retinal layers showed increased activity after exposure whereas in the old animals, the converse was true. DNA-RNA reaction revealed decreased DNA activities in the old animals 30 h after exposure. The results were also correlated with biochemical studies on the uptake of 2-deoxyglucose, dopamine and leucine. 相似文献
129.
Steffen Fritz Linda See Ian McCallum Liangzhi You Andriy Bun Elena Moltchanova Martina Duerauer Fransizka Albrecht Christian Schill Christoph Perger Petr Havlik Aline Mosnier Philip Thornton Ulrike Wood‐Sichra Mario Herrero Inbal Becker‐Reshef Chris Justice Matthew Hansen Peng Gong Sheta Abdel Aziz Anna Cipriani Renato Cumani Giuliano Cecchi Giulia Conchedda Stefanus Ferreira Adriana Gomez Myriam Haffani Francois Kayitakire Jaiteh Malanding Rick Mueller Terence Newby Andre Nonguierma Adeaga Olusegun Simone Ortner D. Ram Rajak Jansle Rocha Dmitry Schepaschenko Maria Schepaschenko Alexey Terekhov Alex Tiangwa Christelle Vancutsem Elodie Vintrou Wu Wenbin Marijn van der Velde Antonia Dunwoody Florian Kraxner Michael Obersteiner 《Global Change Biology》2015,21(5):1980-1992
A new 1 km global IIASA‐IFPRI cropland percentage map for the baseline year 2005 has been developed which integrates a number of individual cropland maps at global to regional to national scales. The individual map products include existing global land cover maps such as GlobCover 2005 and MODIS v.5, regional maps such as AFRICOVER and national maps from mapping agencies and other organizations. The different products are ranked at the national level using crowdsourced data from Geo‐Wiki to create a map that reflects the likelihood of cropland. Calibration with national and subnational crop statistics was then undertaken to distribute the cropland within each country and subnational unit. The new IIASA‐IFPRI cropland product has been validated using very high‐resolution satellite imagery via Geo‐Wiki and has an overall accuracy of 82.4%. It has also been compared with the EarthStat cropland product and shows a lower root mean square error on an independent data set collected from Geo‐Wiki. The first ever global field size map was produced at the same resolution as the IIASA‐IFPRI cropland map based on interpolation of field size data collected via a Geo‐Wiki crowdsourcing campaign. A validation exercise of the global field size map revealed satisfactory agreement with control data, particularly given the relatively modest size of the field size data set used to create the map. Both are critical inputs to global agricultural monitoring in the frame of GEOGLAM and will serve the global land modelling and integrated assessment community, in particular for improving land use models that require baseline cropland information. These products are freely available for downloading from the http://cropland.geo-wiki.org website. 相似文献
130.
Mustafa S See HB Seeber RM Armstrong SP White CW Ventura S Ayoub MA Pfleger KD 《The Journal of biological chemistry》2012,287(16):12952-12965
We have provided the first evidence for specific heteromerization between the α(1A)-adrenoceptor (α(1A)AR) and CXC chemokine receptor 2 (CXCR2) in live cells. α(1A)AR and CXCR2 are both expressed in areas such as the stromal smooth muscle layer of the prostate. By utilizing the G protein-coupled receptor (GPCR) heteromer identification technology on the live cell-based bioluminescence resonance energy transfer (BRET) assay platform, our studies in human embryonic kidney 293 cells have identified norepinephrine-dependent β-arrestin recruitment that was in turn dependent upon co-expression of α(1A)AR with CXCR2. These findings have been supported by co-localization observed using confocal microscopy. This norepinephrine-dependent β-arrestin recruitment was inhibited not only by the α(1)AR antagonist Terazosin but also by the CXCR2-specific allosteric inverse agonist SB265610. Furthermore, Labetalol, which is marketed for hypertension as a nonselective β-adrenoceptor antagonist with α(1)AR antagonist properties, was identified as a heteromer-specific-biased agonist exhibiting partial agonism for inositol phosphate production but essentially full agonism for β-arrestin recruitment at the α(1A)AR-CXCR2 heteromer. Finally, bioluminescence resonance energy transfer studies with both receptors tagged suggest that α(1A)AR-CXCR2 heteromerization occurs constitutively and is not modulated by ligand. These findings support the concept of GPCR heteromer complexes exhibiting distinct pharmacology, thereby providing additional mechanisms through which GPCRs can potentially achieve their diverse biological functions. This has important implications for the use and future development of pharmaceuticals targeting these receptors. 相似文献