2,338 research outputs found

    AQUIFER Nano-Electrofuel Energy Economy and Powered Aircraft Operations

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    The Aqueous, QUick-charging battery Integration For Electric flight Research project is explained and the major subsystems are described, including nano-electric fluid, rim-driven motors, and integration concepts. The nano-electric fluid concept is a new type of aqueous flow battery that could reduce or retire the fire and explosion hazards of conventional batteries and fuel cells. The nano-electric fluid itself could enable energy storage and increased available energy per fuel weight ratios. The rim-driven motor is being developed to improve propulsion system safety and stability and to reduce noise. The rim-driven motor concept could enable motors that are more efficient both electrically and aerodynamically. The Energy Economy of the project concept is presented as a potential renewable or green energy sustainment for utilizing in-place infrastructure. The nano-electric fluid energy charge-use-recharge cycle is presented using renewable energy input from solar, wind, and hydroelectricity. Powered aircraft operations are presented, and the logistics of the new nano-electric fluid technology are explored. Powered aircraft operations topics include weight and balance, fueling, recharging, safety, and derivative considerations

    Pure Expectations: Examining the Meaning and Implications of Virginity Culture

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    The abstract for this presentation can be downloaded by clicking on the blue download button

    Dengue virus type 2: replication and tropisms in orally infected Aedes aegypti mosquitoes

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    BACKGROUND: To be transmitted by its mosquito vector, dengue virus (DENV) must infect midgut epithelial cells, replicate and disseminate into the hemocoel, and finally infect the salivary glands, which is essential for transmission. The extrinsic incubation period (EIP) is very relevant epidemiologically and is the time required from the ingestion of virus until it can be transmitted to the next vertebrate host. The EIP is conditioned by the kinetics and tropisms of virus replication in its vector. Here we document the virogenesis of DENV-2 in newly-colonized Aedes aegypti mosquitoes from Chetumal, Mexico in order to understand better the effect of vector-virus interactions on dengue transmission. RESULTS: After ingestion of DENV-2, midgut infections in Chetumal mosquitoes were characterized by a peak in virus titers between 7 and 10 days post-infection (dpi). The amount of viral antigen and viral titers in the midgut then declined, but viral RNA levels remained stable. The presence of DENV-2 antigen in the trachea was positively correlated with virus dissemination from the midgut. DENV-2 antigen was found in salivary gland tissue in more than a third of mosquitoes at 4 dpi. Unlike in the midgut, the amount of viral antigen (as well as the percent of infected salivary glands) increased with time. DENV-2 antigen also accumulated and increased in neural tissue throughout the EIP. DENV-2 antigen was detected in multiple tissues of the vector, but unlike some other arboviruses, was not detected in muscle. CONCLUSION: Our results suggest that the EIP of DENV-2 in its vector may be shorter that the previously reported and that the tracheal system may facilitate DENV-2 dissemination from the midgut. Mosquito organs (e.g. midgut, neural tissue, and salivary glands) differed in their response to DENV-2 infection

    Análisis de la legislación en materia migratoria e inconvenientes para el flujo de personas extranjeras

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    El objetivo de este estudio es: Analizar la legislación ecuatoriana en materia migratoria y los inconvenientes para el flujo de personas extranjeras. Esto se desarrolla a través de un estudio con enfoque cualitativo, y el empleo de métodos como el analítico-sintético y el inductivo. Tomando en cuenta aportes significativos, con especial interés en el impacto de la aplicación normativa migratoria en el flujo de personas extranjeras cuya garantía constitucional de protección integral, debe ser respetada e implementada por las autoridades competentes, considerando que los abusos y discriminaciones en el contexto laboral y social, son una violación a los derechos de las personas, cuyas sanciones no se implementan adecuadamente por los operadores de justicia, siendo el aspecto negativo de más interés y relevancia. Se concluye en términos generales, que, la política migratoria del actual Gobierno ha sido aplaudida a nivel mundial por los entendidos, al ser uno de los pocos países del mundo, que trata el tema de la movilidad humana bajo el principio de la ciudadanía universal, sin embargo, sí que hacen falta cambios en materia laboral, para que este sea justo e igualitario con los migrantes. Palabras clave: Legislación, migración, flujo de personas, extranjeros.   ABSTRACT The objective of this study is to analyze the Ecuadorian legislation on migration and the drawbacks for the flow of foreigners. This is developed through a study with a qualitative approach, and the use of methods such as bibliographic and documentary analysis, taking into account significant contributions, with special interest in the impact of the application of immigration regulations on the flow of foreigners whose constitutional guarantee of comprehensive protection, must be respected and implemented by the competent authorities, considering that abuses and discrimination in the labor and social context are a violation of the rights of people, whose sanctions are not adequately implemented by justice operators, being the negative aspect of more interest and relevance. It is concluded in general terms that the immigration policy of the current Government has been applauded worldwide by experts, as it is one of the few countries in the world that deals with the issue of human mobility under the principle of universal citizenship, without However, changes are needed in labor matters, so that it is fair and equal with migrants. Keywords: Legislation, migration, flow of people, foreigners

    Compost and Biochar to Promote Soil Biological Activities under Sweet Potatoes Cultivation in a Subtropical Semiarid Region

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    South Texas is located in a subtropical semiarid climate, and due to high temperature and irregular precipitation, farmers opt to leave their fields fallow during the summer months jeopardizing overall soil health. We evaluated whether sweet potato (Ipomoea batatas) cultivation coupled with drip irrigation could restore soil biological activities compared with bare fallow. Additionally, because sweet potatoes have high demand of soil nutrients, especially potassium (K), we evaluated the nutrient supply of locally sourced soil amendments. Sweet potato was cultivated during summer 2018 in McAllen, Texas, under control (no fertilizer), NPK (synthetic fertilizer), RC (yard-waste compost), and AC (compost produced under an enhanced composting process), and biochar (gasified walnut shell at 900°C), each with three replicates. Soil amendments were applied at different amounts to result in a rate of 80 kg K ha−1. Soil biological indicators were microbial biomass phosphorous, phosphatase activity, and the rate of fluorescein diacetate hydrolysis (FDA). Available nitrogen, phosphorus, potassium, and sodium were also quantified. Aboveground biomass and storage root yield estimated sweet potato’s agronomic performance. Cultivation and irrigation stimulated soil enzyme activities and microbial biomass-phosphorous. Sweet potato yields were the highest in NPK treatment but still 2.8 times lower than variety’s potential yield. Storage root yield was inversely related to aboveground biomass, suggesting that growing conditions benefited the production of shoot versus roots. Both biochar and AC treatments stimulated FDA rates and K availability. Soil pH and sodium concentration increased in all treatments over the growing season, possibly due to river-sourced irrigation water. Together, these findings show that crop cultivation promoted soil biological activities and the maintenance of nutrient cycling, compared to bare-fallow conditions. For a better agronomic performance of sweet potato, it would be necessary to identify management practices that minimize increase in soil pH and salinity

    Aurora-A kinase is differentially expressed in the nucleus and cytoplasm in normal Müllerian epithelium and benign, borderline and malignant serous ovarian neoplasms

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    BACKGROUND: Aurora-A kinase is important for cellular proliferation and is implicated in the tumorigenesis of several malignancies, including of the ovary. Information regarding the expression patterns of Aurora-A in normal Müllerian epithelium as well as benign, borderline and malignant epithelial ovarian neoplasms is limited. METHODS: We investigated Aurora-A expression by immunohistochemistry in 15 benign, 19 borderline and 17 malignant ovarian serous tumors, and 16 benign, 8 borderline, and 2 malignant ovarian mucinous tumors. Twelve fimbriae from seven patients served as normal Müllerian epithelium controls. We also examined Aurora-A protein expression by western blot in normal fimbriae and tumor specimens. RESULTS: All normal fimbriae (n = 12) showed nuclear but not cytoplasmic Aurora-A immunoreactivity by immunohistochemistry. Benign ovarian tumors also showed strong nuclear Aurora-A immunoreactivity. Forty-eight percent (13/27) of borderline tumors demonstrated nuclear Aurora-A immunoreactivity, while the remainder (52%, 14/27) lacked Aurora-A staining. Nuclear Aurora-A immunoreactivity was absent in all malignant serous tumors, however, 47% (8/17) demonstrated perinuclear cytoplasmic staining. These results were statistically significant when tumor class (benign/borderline/malignant) was compared to immunoreactivity localization or intensity (Fisher Exact Test, p \u3c 0.01). Western blot analysis confirmed the greater nuclear Aurora-A expression in control Müllerian epithelium compared to borderline and malignant tumors. CONCLUSION: Aurora-A kinase is differentially expressed across normal Müllerian epithelium, benign and borderline serous and mucinous ovarian epithelial neoplasms and malignant serous ovarian tumors., with nuclear expression of unphosphorylated Aurora-A being present in normal and benign neoplastic epithelium, and lost in malignant serous neoplasms. Further studies of the possible biological and clinical implications of the loss of nuclear Aurora-A expression in ovarian tumors, and its role in ovarian carcinogenesis are warranted
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