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171.
Recently sociological analysis of what used to be identified as 'race' and 'race relations' has shifted to racism as an ideology and racialization as a process that ascribes physical and cultural differences to individuals and groups. While scholars have critically examined 'race' and 'race relations', the concept of racialization has received insufficient systematic attention. The purpose of this article is to trace the genealogy of concepts of racialization and deracialization and to demonstrate that the meaning of these designations has changed since their appearance in the late-nineteenth century to the emergence of racialization in contemporary debates on effects of racism; and to trace the different trajectories of racialization from the centre and from the periphery. 相似文献
172.
Anirban Banerjee Rohit Sharma Yusuf Chisti U. C. Banerjee 《Critical reviews in biotechnology》2013,33(3):245-279
ABSTRACT:?Botryococcus braunii, a green colonial microalga, is an unusually rich renewable source of hydrocarbons and other chemicals. Hydrocarbons can constitute up to 75% of the dry mass of B. braunii. This review details the various facets of biotechnology of B. braunii, including its microbiology and physiology; production of hydrocarbons and other compounds by the alga; methods of culture; downstream recovery and processing of algal hydrocarbons; and cloning of the algal genes into other microorganisms. B. braunii converts simple inorganic compounds and sunlight to potential hydrocarbon fuels and feedstocks for the chemical industry. Microorganisms such as B. braunii can, in the long run, reduce our dependence on fossil fuels and because of this B. braunii continues to attract much attention. 相似文献
173.
ABSTRACTTensile and creep properties of dissimilar cold weld joints (Al (metal)–Cu50Zr50 (metallic glass)) are investigated using molecular dynamics simulations. Embedded atom method potential is used to model the interactions between Al–Cu–Zr atoms. Cold welding is carried out at three different velocities (20, 30 and 40?m/s) and for three interferences (0.4, 1.3 and 2.3?nm). The strength of the welded joints is measured using the tensile test carried out at a strain rate of 1.5 × 109/s. Structure studies by radial distribution function analysis indicate amorphisation of Al in the weld regions. Tensile studies show that the maximum strength is obtained in the sample that is welded for 1.3?nm interference. Creep studies carried out over range of stresses (200–350?MPa) and temperatures (200–500?K) show very short primary creep and significant steady-state creep. The stress exponent n has two values; at lower stress, n?=?1.2, and at higher stress, n?=?4.06, respectively. The deformation mechanisms are observed to be slip by Shockley partial dislocation and by twinning in Al region. The icosahedral cluster population in metallic glass decreases as the temperature increases and contributes to large plastic strain. 相似文献
174.
175.
María José León Ana B. Fernández Rohit Ghai Cristina Sánchez-Porro Francisco Rodriguez-Valera Antonio Ventosa 《Applied and environmental microbiology》2014,80(13):3850-3857
Recent metagenomic studies on saltern ponds with intermediate salinities have determined that their microbial communities are dominated by both Euryarchaeota and halophilic bacteria, with a gammaproteobacterium closely related to the genera Alkalilimnicola and Arhodomonas being one of the most predominant microorganisms, making up to 15% of the total prokaryotic population. Here we used several strategies and culture media in order to isolate this organism in pure culture. We report the isolation and taxonomic characterization of this new, never before cultured microorganism, designated M19-40T, isolated from a saltern located in Isla Cristina, Spain, using a medium with a mixture of 15% salts, yeast extract, and pyruvic acid as the carbon source. Morphologically small curved cells (young cultures) with a tendency to form long spiral cells in older cultures were observed in pure cultures. The organism is a Gram-negative, nonmotile bacterium that is strictly aerobic, non-endospore forming, heterotrophic, and moderately halophilic, and it is able to grow at 10 to 25% (wt/vol) NaCl, with optimal growth occurring at 15% (wt/vol) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence comparison showed that strain M19-40T has a low similarity with other previously described bacteria and shows the closest phylogenetic similarity with species of the genera Alkalilimnicola (94.9 to 94.5%), Alkalispirillum (94.3%), and Arhodomonas (93.9%) within the family Ectothiorhodospiraceae. The phenotypic, genotypic, and chemotaxonomic features of this new bacterium showed that it constitutes a new genus and species, for which the name Spiribacter salinus gen. nov., sp. nov., is proposed, with strain M19-40T (= CECT 8282T = IBRC-M 10768T = LMG 27464T) being the type strain. 相似文献
176.
Rohit Surana Sakshi Sikka Wanpei Cai Eun Myoung Shin Sudha R. Warrier Hong Jie Gabriel Tan Frank Arfuso Simon A. Fox Arun M. Dharmarajan Alan Prem Kumar 《生物化学与生物物理学报:癌评论》2014
The Wnt (wingless-type) signaling pathway plays an important role in embryonic development, tissue homeostasis, and tumor progression becaluse of its effect on cell proliferation, migration, and differentiation. Secreted frizzled-related proteins (SFRPs) are extracellular inhibitors of Wnt signaling that act by binding directly to Wnt ligands or to Frizzled receptors. In recent years, aberrant expression of SFRPs has been reported to be associated with numerous cancers. As gene expression of SFRP members is often lost through promoter hypermethylation, inhibition of methylation through the use of epigenetic modifying agents could renew the expression of SFRP members and further antagonize deleterious Wnt signaling. Several reports have described epigenetic silencing of these Wnt signaling antagonists in various human cancers, suggesting their possible role as tumor suppressors. SFRP family members thus come across as potential tools in combating Wnt-driven tumorigenesis. However, little is known about SFRP family members and their role in different cancers. This review comprehensively covers all the available information on the role of SFRP molecules in various human cancers. 相似文献
177.
Sharona Sedighim Yiqing Chen Changlu Xu Rohit Mohindra Huinan Liu Devendra K. Agrawal Finosh G. Thankam 《Biotechnology and bioengineering》2023,120(3):819-835
Cardiac tissue engineering is an emerging approach for cardiac regeneration utilizing the inherent healing responses elicited by the surviving heart using biomaterial templates. In this study, we aimed to develop hydrogel scaffolds for cardiac tissue regeneration following myocardial infarction (MI). Two superabsorbent hydrogels, CAHA2A and CAHA2AP, were developed employing interpenetration chemistry. CAHA2A was constituted with alginate, carboxymethyl cellulose, (hydroxyethyl) methacrylate, and acrylic acid, where CAHA2AP was prepared by interpenetrated CAHA2A with polyvinyl alcohol. Both hydrogels displayed superior physiochemical characteristics, as determined by attenuated total reflection infrared spectroscopy spectral analysis, differential scanning calorimetry measurements, tensile testing, contact angle, water profiling, dye release, and conductivity. In vitro degradation of the hydrogels displayed acceptable weight composure and pH changes. Both hydrogels were hemocompatible, and biocompatible as evidenced by direct contact and MTT assays. The hydrogels promoted anterograde and retrograde migration as determined by the z-stack analysis using H9c2 cells grown with both gels. Additionally, the coculture of the hydrogels with swine epicardial adipose tissue cells and cardiac fibroblasts resulted in synchronous growth without any toxicity. Also, both hydrogels facilitated the production of extracellular matrix by the H9c2 cells. Overall, the findings support an appreciable in vitro performance of both hydrogels for cardiac tissue engineering applications. 相似文献
178.
The budding yeast Mph1 protein, the putative ortholog of human FANCM, possesses a 3' to 5' DNA helicase activity and is capable of disrupting the D-loop structure to suppress chromosome arm crossovers in mitotic homologous recombination. Similar to FANCM, genetic studies have implicated Mph1 in DNA replication fork repair. Consistent with this genetic finding, we show here that Mph1 is able to mediate replication fork reversal, and to process the Holliday junction via DNA branch migration. Moreover, Mph1 unwinds 3' and 5' DNA Flap structures that bear key features of the D-loop. These biochemical results not only provide validation for a role of Mph1 in the repair of damaged replication forks, but they also offer mechanistic insights as to its ability to efficiently disrupt the D-loop intermediate. 相似文献
179.
Reddi Srinu Mada Sanusi Bello Kumar Naveen Kumar Rohit Ahmad Naseer Karvande Anirudh Kapila Suman Kapila Rajeev Trivedi Ritu 《International journal of peptide research and therapeutics》2019,25(3):1147-1158
International Journal of Peptide Research and Therapeutics - In the last decade, several studies have reported health beneficial effects of milk derived bioactive peptides in several degenerative... 相似文献
180.
Helge R?der Mette Vesterhus Abdelfattah El Ouaamari Joao A. Paulo Fiona E. McAllister Chong Wee Liew Jiang Hu Dan Kawamori Anders Molven Steven P. Gygi P?l R. Nj?lstad C. Ronald Kahn Rohit N. Kulkarni 《PloS one》2013,8(4)