320 research outputs found

    Disjunctures within conventional knowledge of black male homosexual identity in contemporary South Africa

    Get PDF
    This thesis provides a sociological understanding of how conventional knowledge of sexuality negates the identity formation of black gay men in contemporary South Africa. It investigates the coming out experiences of six black gay men in order to reveal the disjunctures between being black and being gay. The theoretical formation of disjuncture is pursued through examining a number of sociological, historical, psychoanalytical, and feminist approaches to identity, sexuality, and society; featuring specifically the theories of George Herbert Mead, Michel Foucault, and Judith Butler. The chosen research paradigm is symbolic interactionism, postulating both „pragmatist‟ and „empiricist‟ trends that lead to both interactionist and structuralist forms of argumentation. The interactionist approach to sexuality is central to the deconstruction of sexual conventions. It involves conceptualising modern sexuality in the landscapes of African colonial history and the global gay and lesbian movement. The prescribed literature on homosexuality is thus reviewed in conjunction with the South African gay and lesbian struggle, so as to spawn themes and perspectives for conducting life story interviews. The use of the life story interview favours the participants‟ own view of the studied phenomenon, yet aims to depict the structural influence on homosexual identification. Following the qualitative research tradition, the data analysis is based on the interpretation of narratives. It illustrates interpersonal relationships and microscopic experiences that lead to the self-acceptance and self-actualisation of homosexuality. Within these processes, various disjunctures that exist between the cultural sanction of lifestyle and individual choice, between parents and children, between religious belief and personal desires, and between gender identity and sexual orientation are disclosed. The findings are associated with the historical transformation of masculinity in South Africa, sex role performance, and the heterosexualisation of desire. The solution to the proposed research problem is discussed through concepts of socialisation and gender conformity

    A Pore-Skeleton-based Method for Calculating Permeability and Capillary Pressure

    Get PDF

    Community prevalence of carbapenemase-producing Gram-negative bacteria

    Get PDF
    Purpose: To raise awareness of carbapenemase-producing organisms, identify “at-risk” patients when admitted in a medical healthcare facility, and to outline effective infection prevention and control measures in order to halt the entry and spread of these organisms. Methods: A total of 1043 un-duplicated urine specimens of healthy volunteers who had no travel history or history of hospitalization were screened. The carbapenemase genotype of each imipenem-resistant strain was determined. Molecular typing and homology analysis of the main carbapenemase-producing strains were used to reveal the mode of transmission of resistance genes. Through transfer joint experiments, the potential risk of spread of carbapenemase genes was assessed. Results: A total of 19 carbapenemase-producing strains from 1,043 non-duplicated healthy volunteers (1.82 %) were identified. The main carbapenemase-producing organism was E. coli (42.1 %, 8/19). The main carbapenemase genotype of E. coli was blaKPC-2 (7 strains). Results from multi-locus sequence typing (MLST) indicated that 7 E. coli isolates belonged to ST-10, ST-101, ST-131, ST-405, ST-410 and ST-1193 and ST-2562. Homologous cluster analysis revealed that the sequence types among the 7 E. coli were high in diversity. The blaKPC-2 gene was successfully transferred from these isolates to 10.22-14 via conjugation. All recipient cells showed marked decreases in carbapenem sensitivity to imipenem (p < 0.05)). The degrees of conjugation were 2.10±0.12 ×10-4, 1.96±0.14×10-4, 2.72±0.18 ×10-4, 3.15±0.20 × 10-4, 2.92±0.23 ×10-4, 3.50±0.20 ×10-4 and 4.12±0.24 ×10-4 in recipient cells of TC7.23-51, TC8.9-42, TC8.15-11, TC8.23-59-3, TC8.23-83, TC9.08-47 and TC10.13-15, respectively. Conclusion: The findings demonstrate the pattern and features of carbapenemase-insensitive E. coli. The blaKPC-2 was the main community-prevalent gene of carbapenem-resistant E. coli. In view of increasing incidence of resistance to multi-drug therapy, surveillance of insensitivity to antibiotics is vital, especially urinary system infection due to carbapenem-insensitive E. coli

    ESIA: An Efficient and Stable Identity Authentication for Internet of Vehicles

    Full text link
    Decentralized, tamper-proof blockchain is regarded as a solution to a challenging authentication issue in the Internet of Vehicles (IoVs). However, the consensus time and communication overhead of blockchain increase significantly as the number of vehicles connected to the blockchain. To address this issue, vehicular fog computing has been introduced to improve efficiency. However, existing studies ignore several key factors such as the number of vehicles in the fog computing system, which can impact the consensus communication overhead. Meanwhile, there is no comprehensive study on the stability of vehicular fog composition. The vehicle movement will lead to dynamic changes in fog. If the composition of vehicular fog is unstable, the blockchain formed by this fog computing system will be unstable, which can affect the consensus efficiency. With the above considerations, we propose an efficient and stable identity authentication (ESIA) empowered by hierarchical blockchain and fog computing. By grouping vehicles efficiently, ESIA has low communication complexity and achieves high stability. Moreover, to enhance the consensus security of the hierarchical blockchain, the consensus process is from the bottom layer to the up layer (bottom-up), which we call B2UHChain. Through theoretical analysis and simulation verification, our scheme achieves the design goals of high efficiency and stability while significantly improving the IoV scalability to the power of 1.5 (^1.5) under similar security to a single-layer blockchain. In addition, ESIA has less communication and computation overhead, lower latency, and higher throughput than other baseline authentication schemes

    Integrin α6 targeted cancer imaging and therapy

    Get PDF
    Integrins represent ideal targets for molecular imaging and targeted therapy of cancer and their role in cancer has been reviewed extensively elsewhere. Except for αVβ3 and αVβ5, the remaining integrins were not systematically considered and tested as potential therapeutic targets. In recent years, the studies on integrin α6 as a cancer imaging and therapeutic target are increasing, due to their highly expressed in several cancers, and their expression has been associated with poor survival. Integrin α6 appears to be a particularly attractive target for cancer imaging and therapy, and therefore we have developed a wide array of integrin α6-target molecular probes for molecular imaging and targeted therapy of different cancers. Despite the studies on integrin α6 as a cancer imaging and therapeutic target increasing in recent years, most of them were derived from preclinical mouse models, revealing that much more can be done in the future. The development of integrin α6 drugs may now be at an important point, with opportunities to learn from previous research, to explore new approaches. In this review, we will briefly introduce integrin α6 and highlighted the recent advances in integrin α6 targeted imaging and therapeutics in cancer

    Design, synthesis, and biological activity of novel heptacyclic pyrazolamide derivatives : a new candidate of dual-target insect growth regulators

    Get PDF
    Insect growth regulators (IGRs) can cause abnormal growth and development in insects, resulting in incomplete metamorphosis or even death of the larvae. Ecdysone receptor (EcR) and chitinase in insects play indispensable roles in the molting process. Ecdysone analogues and chitinase inhibitors are considered as potential IGRs. In order to find new and highly effective IGR candidates, based on the structure-activity relationship and molecular docking results of the active compound 6i (3-(tert-butyl)-N-(4-(tert-butyl)phenyl)-1-phenyl-1H-pyrazole-5-carboxamide) discovered in our previous work, we changed the t-butyl group on the pyrazole ring into heptacycle to enhance the hydrophobicity. Consequently, a series of novel heptacyclic pyrazolamide derivatives were designed and synthesized. The bioassay results demonstrated that some compounds showed obvious insecticidal activity. Especially, D-27 (N-(4-(tert-butyl)phenyl)-2-phenyl-2,4,5,6,7,8-hexahydrocyclohepta[c]pyrazole-5-carboxamide) showed good activities against Plutella xylostella (LC50, 51.50 mg.L-1) and Mythimna separata (100% mortality at 2.5 mg.L-1). Furthermore, protein validation indicated that D-27 acts not only on the EcR but also on chitinase Of ChtI. Molecular docking and molecular dynamics simulation explained the vital factors in the interaction between D-27 and receptors. D-27 may be a new lead candidate with a dual target in which Of ChtI shall be the main one. This work created a new starting point for discovering a novel type of IGRs

    Prime-Boost Vaccine Regimen for SjTPl and SjC23 Schistosome Vaccines, Increases Efficacy in Water Buffalo in a Field Trial in China

    Get PDF
    Schistosomiasis remains a serious zoonotic disease in China and the Philippines. Water buffalo and cattle account for the majority of transmission. Vaccination of water buffalo is considered a key strategy to reduce disease prevalence. Previously, we showed that vaccination of water buffalo with SjC23 or SjCTPI plasmid DNA vaccines, induced 50% efficacy to challenge infection. Here, we evaluated several parameters to determine if we can develop a two dose vaccine that maintains the efficacy of the three dose vaccine. We performed four trials evaluating: (1) lab produced vs. GLP grade vaccines, (2) varying the time between prime and boost, (3) the influence of an IL-12 adjuvant, and (4) a two dose heterologous (DNA-protein) prime-boost. We found the source of the DNA vaccines did not matter, nor did increasing the interval between prime and boost. Elimination of the IL-12 plasmid lowered homologous DNA-DNA vaccine efficacy. A major finding was that the heterologous prime boost improved vaccine efficacy, with the prime-boost regimen incorporating both antigens providing a 55% reduction in adult worms and 53% reduction in liver eggs. Vaccinated buffalo produced vaccine-specific antibody responses. These trials suggest that highly effective vaccination against schistosomes can be achieved using a two dose regimen. No adjuvants were used with the protein boost, and the potential that addition of adjuvant to the protein boost to further increase efficacy should be evaluated. These results suggest that use of these two schistosome vaccines can be part of an integrated control strategy to reduce transmission of schistosomiasis in Asia
    corecore