157 research outputs found

    World Wide Epidemiology of Helminths Infection

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    Helminths (from the Greek Helmins, meaning worm) include three groups of parasitic worm, large multicellular organisms with complex tissues and organs. Helminths do not replicate within the human host except Strongyloides stercoralis. Prevalence is commonly combined with worm burden (intensity of infection), which is commonly measured by the number of eggs per gram (EPGs) of faeces for intestinal helminths and schistosomes. Based on EPGs and their association with morbidity, individuals are classified into categories of light, moderate and heavy infection by the WHO. In the case of soil‐transmitted helminths, the WHO recommends use of both prevalence and intensity of infection to classify communities into transmission categories—category I (high), category II (medium), and category III (low). The neglected status of the helminthiasis should be addressed on community levels and globally all over the world

    Assessment of magmatic versus post-magmatic processes in the Mueilha rare-metal granite, Eastern Desert of Egypt, Arabian-Nubian Shield

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    The Mueilha rare-metal granite, exposed in the central Eastern Desert of Egypt, is a post-collisional intrusion that formed in the final magmatic stage of the evolution of the Arabian-Nubian Shield. The Mueilha intrusion was emplaced as a high-level magmatic cupola into metamorphic country rocks. It consists of two cogenetic intrusive bodies: an early phase emplaced at shallow depth and now penetratively altered to white albite granite and a later phase of red granites emplaced at greater depth that better preserve magmatic features. The albite granite is less common and represents the upper margin of the Mueilha intrusion, the apex of the magmatic cupola. The red granites are volumetrically dominant and appears to have crystallized from the margins inward, forming a composite pluton zoned from muscovite granite to alkali feldspar granite. All parts of the Mueilha pluton appear to have been emplaced within a short time interval, before complete crystallization of the earliest phase. The geochemistry of the Mueilha granites is typical of rare-metal granites, characterized by high SiO₂, Na₂O + K₂O, Nb, Rb, Ta, Y, U, Th, Sn, and W with depletion in P, Mg, Ti, Sr and Ba. They are weakly peraluminous and highly fractionated with A-type character. The chondrite-normalized REE patterns have strongly negative Eu anomalies, typical of highly differentiated granites that evolved through a transitional magmatic–hydrothermal stage. The primary magma feeding the Mueilha intrusion was generated by partial melting of the juvenile crust of the Arabian-Nubian Shield; it subsequently underwent extensive fractional crystallization and metasomatism by late- to post-magmatic fluids. Separation of fluids from the oversaturated melt promoted both diffuse greisenization and focused segregation of pegmatite and fluorite and quartz veins. Alkalis liberated from feldspars consumed by greisenization were redeposited during albitization in the uppermost part of the magma chamber. Despite penetration of the intrusion boundary by discrete dikes, veins, and aphophyses, diffuse alteration of the metamorphic country rocks is not apparent. Primary columbite-series minerals crystallized from the melt and were later partly replaced by secondary Nb and Ta minerals (fluorcalciomicrolite and wodginite) during hydrothermal alteration

    Heavy Meson Production at COSY - 11

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    The COSY-11 collaboration has measured the total cross section for the pp --> pp eta-prime and pp --> pp eta reactions in the excess energy range from Q = 1.5 MeV to Q = 23.6 MeV and from Q = 0.5 MeV to Q = 5.4 MeV, respectively. Measurements have been performed with the total luminosity of 73 nb^(-1) for the pp --> pp eta reaction and 1360 nb^(-1) for the pp --> pp eta-prime one. Recent results are presented and discussed.Comment: Invited talk at 4th International Conference on Physics at Storage Rings (STORI 99), Bloomington, Indiana, USA, September 12-16, 199

    Enhancement Reinforcing Concrete Beams Using Polypropylene Cord-Knitted Bars

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    Currently, technical fabrics play a major role in many industries due to their multiple characteristics. The aim of this research was to utilize composite knitted bars to reinforce concrete beams. Six cord-knitted samples with two different polypropylene yarn counts (outer layer) and three different core materials were manufactured and immersed in a local epoxy material (Kemapoxy 150). Composite knitted bars were prepared in this way. Several tests were conducted for fabrics and knitted bar samples. All data were collected and analysed using two different tools: ANOVA test and radar chart area. Finally, three concrete beams with a varying number of cord-knitted bars (one bar, two bars and three bars) were produced. The results indicated that the differences in outer and core yarns for cord-knitted samples have a significant effect on several fabric and bar characteristics. The knitted bars with PP core yarn can be more beneficial for concrete that do does not require high stress, while the knitted bars using glass fibres and polypropylene (50% and 50% PE) as core materials are not appropriate for applications that require more flexibility and extensibility. Reinforced concrete beams were improved significantly with cord-knitted bars, taking into account the number of bars per area, which may cause the minimizing of flexure force through an increase in that number of bars per area

    Near-Threshold eta Meson Production in Proton-Proton Collisions

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    The production of eta mesons has been measured in the proton-proton interaction close to the reaction threshold using the COSY-11 internal facility at the cooler synchrotron COSY. Total cross sections were determined for eight different excess energies in the range from 0.5 MeV to 5.4 MeV. The energy dependence of the total cross section is well described by the available phase-space volume weighted by FSI factors for the proton-proton and proton-eta pairs.Comment: 9 pages, 1 table, 5 figure

    Continuum-mechanical, Anisotropic Flow model for polar ice masses, based on an anisotropic Flow Enhancement factor

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    A complete theoretical presentation of the Continuum-mechanical, Anisotropic Flow model, based on an anisotropic Flow Enhancement factor (CAFFE model) is given. The CAFFE model is an application of the theory of mixtures with continuous diversity for the case of large polar ice masses in which induced anisotropy occurs. The anisotropic response of the polycrystalline ice is described by a generalization of Glen's flow law, based on a scalar anisotropic enhancement factor. The enhancement factor depends on the orientation mass density, which is closely related to the orientation distribution function and describes the distribution of grain orientations (fabric). Fabric evolution is governed by the orientation mass balance, which depends on four distinct effects, interpreted as local rigid body rotation, grain rotation, rotation recrystallization (polygonization) and grain boundary migration (migration recrystallization), respectively. It is proven that the flow law of the CAFFE model is truly anisotropic despite the collinearity between the stress deviator and stretching tensors.Comment: 22 pages, 5 figure
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