Quasi two-level PWM operation of a nine-arm modular multilevel converter for six-phase medium-voltage motor drives

This paper proposes a hybrid converter for medium-voltage six-phase machine drive systems that mixes the operation of a traditional two-level voltage-source inverter and the modular multilevel converter (MMC) to enable operation over a wide frequency range. Topologically, the proposed converter consists of nine arms resembling two sets of three-phase MMCs with three common arms, yielding a nine-arm MMC with a 25% reduction in the number of employed arms compared to a traditional dual three-phase MMC. The multilevel property of a standard MMC is emulated in the proposed converter, however on a two-level basis, resulting in a stepped two-level output voltage waveform. The proposed converter has a reduced footprint with advantages of small voltage steps, modular structure, and ease of scalability. Further, it is able to drive high-power six-phase machines within low operating frequencies at the rated torque. The operating principle of the converter is elaborated, and its modulation scheme is discussed. The features of the proposed converter are verified through simulations and experimentally

The institutional logics of localization programs in GCC developing countries

This study explains the sociopolitical impacts of localization programs by focusing on some Gulf Cooperation Council (GCC) countries, such as Saudi Arabia, Qatar and UAE. This study is based on secondary data collected from the review of previous relevant studies and data available on the Internet. Despite contributing to achieving some political and social goals, these programs have serious impacts concerning the quality of work to be done in the labor and the business (economic) environment. This study alerts the international society to the various perspectives of the locally-taken decisions or implemented programs

Rural Women Empowerment in New Valley Governorate, Egypt

Aims: The objectives of this study are to: i) Measure the rural women’s empowerment level, and ii) Determine factors affecting rural women’s empowerment level. Study Design: One-time point cross-sectional study. Place and Duration of Study: Data were collected through personal interviews of 300 rural women (240 from Al-Mounirah village belonging to El-Kharga district and 60 ones from Al-Thaniyah (the second) village belonging to Darb El-Arbaien, Paris District), during the period from May to June, 2016 using a questionnaire form. Methodology: Frequencies, percentages, range, average, standard deviation, weighted average (relative weight), T test, Pearson’s simple correlation, Step-Wise Regression Analysis, and verification of hypotheses were used for data processing and presentation. Results: Findings revealed that dimensions of rural women’s empowerment could be ranked as social (relative weight = 60.8%), cognitive and psychological (RW = 60.7% for each), economic (RW = 58.7%), and finally the political dimension of empowerment (RW = 56%). Of the studied eleven independent variables, eight variables accounted for 71.9% of variance in rural women’s economic empowerment, seven accounted for 61.7% of variance in political empowerment, eight accounted for 69.6% of variance in social dimension, one accounted for 4% and 1.6 of variance in cognitive and psychological dimensions, respectively. Results also indicated that the eight independent variables (family type, average of sons’ education, average age of sons, family size, women’s age, women’s employment status, and husband’s age) accounted for 63.4% of variance in rural women’s overall empowerment. Conclusion: The study concluded that rural women’s empowerment could be strengthened through support factors influencing it

Longitudinal Hierarchy Co3O4 Mesocrystals with High-dense Exposure Facets and Anisotropic Interfaces for Direct-Ethanol Fuel Cells

Novel electrodes are needed for direct ethanol fuel cells with improved quality. Hierarchical engineering can produce catalysts composed of mesocrystals with many exposed active planes and multi-diffused voids. Here we report a simple, one-pot, hydrothermal method for fabricating Co 3 O 4 /carbon/substrate electrodes that provides control over the catalyst mesocrystal morphology (i.e., corn tubercle pellets or banana clusters oriented along nanotube domains, or layered lamina or multiple cantilevered sheets). These morphologies afforded catalysts with a high density of exposed active facets, a diverse range of mesopores in the cage interior, a window architecture, and vertical alignment to the substrate, which improved efficiency in an ethanol electrooxidation reaction compared with a conventional platinum/carbon electrode. On the atomic scale, the longitudinally aligned architecture of the Co 3 O 4 mesocrystals resulted in exposed low- and high-index single and interface surfaces that had improved electron transport and diffusion compared with currently used electrodes

The appearance of CSR Responsiveness in Times of crisis:UK Evidence

Purpose: The COVID-19 pandemic had a devastating impact on various corporate practices, including social activities. This impact was anticipated to motivate many companies to focus on short-term gains and postpone CSR-related investments, an issue that worth a detailed examination. Therefore, this study examines whether CSR reporting by UK companies was influenced by the COVID-19 pandemic.Methodology: We investigated CSR reported by UK companies’ C-Suite during the pandemic. Using textual analysis, we analysed UK companies’ CEOs and Chairmen statements/letters in 2020/2021. Findings: We found that C-Suite CSR reports during COVID-19 focused on employees’ moral support, safety, and online customer support, with less attention being paid to environmental performance and an ignorance of certain CSR elements such as climate change and equality. This finding confirms the context-dependent nature of CSR during crises and explains how it is configured by mega-events at the societal level.Originality: The evidence reported in this study is beneficial for understanding how global crises can reconfigure companies’ top management perceptions of CSR

The role of PLK1 in Hepatitis B Virus (HBV) infection of the liver

With 250 million reported chronic infections globally, Hepatitis B Virus (HBV) is a major human health issue, linked to increased risk for development of hepatocellular carcinoma (HCC). Current treatments to control chronic HBV infection remain ineffective. New and effective therapies that target the persisting viral molecules are needed in order to clear infection. My research aims to understand the role of hepatitis B virus (HBV) in inducing HCC and identify novel host molecules that are targeted by HBV. Understanding how HBV modifies and manipulates host cellular pathways is critical for the development of mechanism based therapeutics. Here, I provide a review for the HBV core protein (HBc), its function and the host molecules it usurps during infection and pathogenesis. I also identify Polo-like-kinase 1 (PLK1) as a proviral factor in HBV pathogenesis. I demonstrate by loss of function as well as gain of function approaches that PLK1 inhibition suppresses viral replication both in vitro and in vivo. I also show that HBc is a phosphorylation substrate for PLK1 in vitro and I mapped the PLK1 phosphorylation sites to HBc residues S168, S176 and S178. Finally, I used a global proteomics approach to study human HBc interactome identifying potential interacting partners with interesting links to viral pathogenesis. Collectively, my research expands our understanding of the role of HBc in HBV pathogenesis and the ensuing transformation of the liver