6,960 research outputs found

    Feeding habits of anophelines (Diptera: Culicidae) in 1971-78, with reference to the human blood index: a review

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    A synoptic view is given of the data amassed by WHO, with technical assistance from the Imperial College of Science and Technology, on the origins of blood-meals in Anopheles samples collected from 1971 to 1978. Attention is focused on the proportion of each sample found to contain human blood and on the problems of interpreting from this the human blood index or degree of biting-contact with man exhibited by vector populations. The difficulties of overcoming bias in sampling, which are formidable in unsprayed areas, are further compounded where the dwellings are treated with a slow-acting residual insecticide which knocks down many engorged mosquitoes before they can be collected from their daytime resting places. There is evidence to suggest that the host-selection patterns of those vectors which are ‘opportunistic' feeders may be heavily influenced, even from village to village or from month to month, by the changing availability of alternative hosts, particularly cattle. This suggests in turn that the possibilities of manipulating the degree of mosquito-man contact by encouraging deflection to animals (zooprophylaxis) or by measures to afford a degree of personal protection should not be under-estimated by malaria strategists. It may sometimes be found less difficult to reduce the vector's human blood index than it is to measure it, but in view of the epidemiological importance of this parameter, suggestions are put forward for improving entomological field practice in this area. They include a quantitative survey of the biotopes available to the mosquito population as diurnal shelters, a longitudinal survey of the densities of blood-fed females per biotope, and a survey of the numbers and the respective distribution of people and domestic animals available as hosts. The work-load entailed by such a thorough form of investigation, to be repeated where necessary at different seasons of the year, underlines the necessity to concentrate efforts on a small number of localities, carefully chosen for the malaria situations they represent and the vector populations they support. A large-scale blood-meal sampling programme, confined to these selected localities, is most likely in our estimation to yield information of value for controlling malaria vector

    Water poverty in the northeastern hill region (India): potential alleviation through multiple-use water systems: cross-learnings from Nepal Hills

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    Water poverty index / Construction / Multiple use / Water storage / Farming systems / Villages / Social aspects / Drip irrigation / India / Nepal / Nagaland / Mon district / Lampong Sheanghah

    Seasonal Abundance of Adult and Immature Aedes Aegypti (L.) in Jakarta

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    Dari bulan Mei 1973 sampai bulan Juni 1974 telah dilakukan pengamatan nyamuk Aedes aegypti stadium dewasa dan larva di keempat daerah kota yang berpenduduk padat di Jakarta Raya. Pengamatan dikerjakan 2 kali dalam satu bulan Daya tarik nyamuk terhadap manusia rata-rata 1.2 induk betina dan 1.6 untuk nyamuk jantan tiap orang tiap jam. Dalam 100 rumah diketemukan rata-rata 180 buah bejana berisi air, dimana 58 buah positif; Container index (persentasi bejana yang tositif) 32 persen House index (persentasi rumah yang positif) adalah 47 persen dan Breteau index jumlah bejana positif dalam 100 rumah) adalah 58. Kepadatan nyamuk baik larva maupun dewasa rata-rata hampir sama sepanjang tahun, (tidak ada perbedaan pada musim hujan dan musim panas), temperatur dan kelembaban juga rata-rata hampir sama sepanjang tahun. hampir semua tempat perindukan terdapat didalam rumah, hingga sedikit sekali bejana diluar rumah yang terisi oleh air hujan dalam musim hujan

    Charge and Spin Response of the Spin--Polarized Electron Gas

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    The charge and spin response of a spin--polarized electron gas is investigated including terms beyond the random phase approximation. We evaluate the charge response, the longitudinal and transverse spin response, and the mixed spin--charge response self--consistently in terms of the susceptibility functions of a non--interacting system. Exchange--correlation effects between electrons of spin σ\sigma and σ\sigma^{'} are included following Kukkonen and Overhauser, by using spin--polarization dependent generalized Hubbard local field factors Gσ±{G_\sigma}^{\pm} and Gσˉ±{G_{\bar\sigma}}^{\pm}. The general condition for charge--density and spin--density--wave excitations of the system is discussed.Comment: 4 pages, latex, no figure

    Shape Invariant Potential and Semi-Unitary Transformations (SUT) for Supersymmetric Harmonic Oscillator in T4-Space

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    Constructing the Semi - Unitary Transformation (SUT) to obtain the supersymmetric partner Hamiltonians for a one dimensional harmonic oscillator, it has been shown that under this transformation the supersymmetric partner loses its ground state in T^{4}- space while its eigen functions constitute a complete orthonormal basis in a subspace of full Hilbert space. Keywords: Supersymmetry, Superluminal Transformations, Semi Unitary Transformations. PACS No: 14.80L

    Clinical Prognostic Value of RNA Viral Load and CD4 Cell Counts during Untreated HIV-1 Infection—A Quantitative Review

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    Background: The prognostic value of CD4 counts and RNA viral load for identifying treatment need in HIV-infected individuals depends on (a) variation within and among individuals, and (b) relative risks of clinical progression per unit CD4 or RNA difference. Methodology/Principal Findings: We reviewed these measurements across (a) 30 studies, and (b) 16 cohorts of untreated seropositive adults. Median within-population interquartile ranges were 74,000 copies/mL for RNA with no significant change during the course of infection; and 330 cells/μL for CD4, with a slight proportional increase over infection. Applying measurement and physiological fluctuations observed on chronically infected patients, we estimate that 45% of population-level variation in RNA, and 25% of variation in CD4, were due to within-patient fluctuations. Comparing a patient with RNA at upper 75th centile with a patient at median RNA, 5-year relative risks were 1.4 (95% CI 1.2-1.7) for AIDS and 1.5 (1.3-1.9) for death, without change over the course of infection. In contrast, for a patient with CD4 count at the lower 75th centile, relative risks increased from 1.0 at seroconversion to maxima of 6.3 (4.4-8.9) for AIDS and 5.5 (2.7-10.1) for death by year 6, when the population median had fallen to 300 cells/ μL. Below 300 cells/μL, prognostic power did not increase, due to a narrower CD4 range. Conclusions: Findings support the current WHO recommendation (used with clinical criteria) to start antiretroviral treatment in low-income settings at CD4 thresholds of 200-350 cells/μL, without pre-treatment RNA monitoring - while not precluding earlier treatment based on clinical, socio-demographic or public health criteria

    Background measurements and detector response studies for ISMRAN experiment

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    We report the measurement of the non-reactor environmental backgrounds and the detector response with the Indian Scintillator Matrix for Reactor Anti-Neutrinos (ISMRAN), which is \sim1 ton detector setup by volume, consisting of 10×\times9 (10 rows and 9 columns) Plastic Scintillator Bars (PSBs) array at BARC, Mumbai, India. ISMRAN is an above-ground anti-neutrino (νe\mathrm{\overline\nu_{e}}) experiment at very short baseline located at Dhruva research reactor facility. It is enclosed by a shielding made of 10 cm thick lead and 10 cm thick borated polyethylene to minimize the backgrounds and is mounted on a movable base structure, situated at \sim 13 m away from the reactor core. These measurements are useful in the context of the ISMRAN detector setup that will be used to detect the reactor νe\mathrm{\overline\nu_{e}} and measure its energy spectrum through the inverse beta decay (IBD) process. In this paper, we present the energy resolution model and energy non-linearity model of PSB and the cosmogenic muon-induced background, based on the sum of their energy depositions and number of hit bars. Reconstructed sum energy spectrum and number of hit bars distribution for 22Na\mathrm{{}^{22}Na} radioactive source has been compared with Geant4 based Monte Carlo simulations. These experimentally measured results will be useful for discriminating the correlated and uncorrelated background events from the true IBD events in reactor ON and OFF conditions inside the reactor hall.Comment: 4 pages, 4 figures. arXiv admin note: text overlap with arXiv:2208.0349

    Cell transformation assays for prediction of carcinogenic potential: State of the science and future research needs

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    Copyright @ 2011 The Authors. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.Cell transformation assays (CTAs) have long been proposed as in vitro methods for the identification of potential chemical carcinogens. Despite showing good correlation with rodent bioassay data, concerns over the subjective nature of using morphological criteria for identifying transformed cells and a lack of understanding of the mechanistic basis of the assays has limited their acceptance for regulatory purposes. However, recent drivers to find alternative carcinogenicity assessment methodologies, such as the Seventh Amendment to the EU Cosmetics Directive, have fuelled renewed interest in CTAs. Research is currently ongoing to improve the objectivity of the assays, reveal the underlying molecular changes leading to transformation and explore the use of novel cell types. The UK NC3Rs held an international workshop in November 2010 to review the current state of the art in this field and provide directions for future research. This paper outlines the key points highlighted at this meeting
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