6,483 research outputs found
Tracking filter and multi-sensor data fusion
In this paper factorization filtering, fusion filtering strategy and related algorithms are presented. Some results of implementation and validation using realistic data are given
Barrier modification in sub-barrier fusion reactions using Wong formula with Skyrme forces in semiclassical formalism
We obtain the nuclear proximity potential by using semiclassical extended
Thomas Fermi (ETF) approach in Skyrme energy density formalism (SEDF), and use
it in the extended -summed Wong formula under frozen density
approximation. This method has the advantage of allowing the use of different
Skyrme forces, giving different barriers. Thus, for a given reaction, we could
choose a Skyrme force with proper barrier characteristics, not-requiring extra
``barrier lowering" or ``barrier narrowing" for a best fit to data. For the
Ni+Mo reaction, the -summed Wong formula, with effects of
deformations and orientations of nuclei included, fits the fusion-evaporation
cross section data exactly for the force GSkI, requiring additional barrier
modifications for forces SIII and SV. However, the same for other similar
reactions, like Ni+Ni, fits the data best for SIII force.
Hence, the barrier modification effects in -summed Wong expression
depends on the choice of Skyrme force in extended ETF method.Comment: INPC2010, Vancouver, CANAD
Chirped pulse Raman amplification in plasma: high gain measurements
High power short pulse lasers are usually based on chirped pulse amplification (CPA), where a frequency chirped and temporarily stretched ``seed'' pulse is amplified by a broad-bandwidth solid state medium, which is usually pumped by a monochromatic ``pump'' laser. Here, we demonstrate the feasibility of using chirped pulse Raman amplification (CPRA) as a means of amplifying short pulses in plasma. In this scheme, a short seed pulse is amplified by a stretched and chirped pump pulse through Raman backscattering in a plasma channel. Unlike conventional CPA, each spectral component of the seed is amplified at different longitudinal positions determined by the resonance of the seed, pump and plasma wave, which excites a density echelon that acts as a "chirped'" mirror and simultaneously backscatters and compresses the pump. Experimental evidence shows that it has potential as an ultra-broad bandwidth linear amplifier which dispenses with the need for large compressor gratings
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The Evolution of Mentorship Capacity Development in Low- and Middle-Income Countries: Case Studies from Peru, Kenya, India, and Mozambique.
Following the Fogarty International Center-supported "Mentoring the Mentors" workshops in South America, Africa, and Asia, approaches and guidelines for mentorship at institutions within these low- and middle-income country (LMIC) contexts, appropriate for the respective regional resources and culture, were implemented. Through the presentation of case studies from these three geographic regions, this article illustrates the institutional mentorship infrastructure before the workshop and the identified gaps used to implement strategies to build mentorship capacity at the Universidad Peruana Cayetano Heredia (Peru), Kenya Medical Research Institute (Kenya), Saint John's Research Institute (India), and Eduardo Mondlane University (Mozambique). These case studies illustrate three findings: first, that mentorship programs in LMICs have made uneven progress, and institutions with existing programs have exhibited greater advancement to their mentoring capacity than institutions without formal programs before the workshops. Second, mentoring needs assessments help garner the support of institutional leadership and create local ownership. Third, developing a culture of mentorship that includes group mentoring activities at LMIC institutions can help overcome the shortage of trained mentors. Regardless of the stage of mentoring programs, LMIC institutions can work toward developing sustainable, culturally effective mentorship models that further the partnership of early career scientists and global health
Field Localization and Enhancement of Phase Locked Second and Third Harmonic Generation in Absorbing Semiconductor Cavities
We predict and experimentally observe the enhancement by three orders of
magnitude of phase mismatched second and third harmonic generation in a GaAs
cavity at 650nm and 433nm, respectively, well above the absorption edge. Phase
locking between the pump and the harmonics changes the effective dispersion of
the medium and inhibits absorption. Despite hostile conditions the harmonics
become localized inside the cavity leading to relatively large conversion
efficiencies. Field localization plays a pivotal role and ushers in a new class
of semiconductor-based devices in the visible and UV ranges
Phytotoxicity, cytotoxicity and genotoxicity evaluation of organic and inorganic pollutants rich tannery wastewater from a Common Effluent Treatment Plant (CETP) in Unnao district, India using Vigna radiata and Allium cepa
The leather industry is a major source of environmental pollution in India. The wastewater generated by leather industries contains very high pollution parameters due to the presence of a complex mixture of organic and inorganic pollutants even after the treatment at a Common Effluent Treatment Plant (CETP) and disturbs the ecological flora and fauna. The nature, characteristics and toxicity of CETP treated wastewater is yet to be fully elucidated. Thus, this study aims to characterize and evaluate the toxicity of CETP treated tannery wastewater collected from the Unnao district of Uttar Pradesh, India. In addition to measuring the physico-chemical parameters, the residual organic pollutants was identified by GC-MS analysis and phytotoxicity, cytotoxicity and genotoxicity of the treated wastewater was evaluated using Vigna radiata L. and Allium cepa L. Results showed that the treated wastewater contained very high pollution parameters (TDS 3850mg/L, BOD 680mg/L, COD-1300mg/L). GC-MS analysis revealed the presence of various types of residual organic pollutants including benzoic acid, 3-[4,-(T-butyl) Phenyl] furan-2-5-dione, benzeneacetamide, resorcinol, dibutyl phthalate, and benzene-1,2,4-triol. Further, toxicological studies showed the phytotoxic nature of the wastewater as it inhibited seed germination in V. radiata L. and root growth of A. cepa. Genotoxicity was evidenced in the root tip cell of A. cepa where chromosomal aberrations (stickiness, chromosome loss, C-mitosis, and vagrant chromosome) and nuclear abnormalities like micronucleated and binucleated cells were observed. Thus, results suggested that it is not safe to discharge these wastewater into the environment
Need of luteinizing hormone for early pregnancy in the golden hamster (Mesocricetus auratus)
Administration of LH antiserum to intact pregnant hamsters on any day from Days 6 to 11 of pregnancy resulted in termination of gestation. Following LH antiserum injection, the ovarian weights were markedly reduced
Low-stress mechanical properties and fabric hand of cotton and polylactic acid fibre blended knitted fabrics
Low-stress mechanical behavior of cotton-rich/polylacticacid blended fabrics has been investigated and the results arecompared with cotton and polylactic acid fibre fabrics. Thepolylactic acid fibres are mixed with cotton fibres in two differentproportions, namely 20% and 35% and spun into 14.76 tex (40sNe) yarn. The yarns are then knit into single jersey structurefollowed by chemical pretreatments and relaxation. The relaxedfabrics are tested for low-stress mechanical properties usingKawabata evaluation system for fabrics (KES-F) and the handvalues are calculated. The results show that the addition of PLAfibres to cotton enhances the smoothness and softness of theblended fabrics. The total hand value of the fabrics rangesbetween 3.2 and 3.5
Chirped pulse Raman amplification in plasma
Raman amplification in plasma has been proposed to be a promising method of amplifying short radiation pulses. Here, we investigate chirped pulse Raman amplification (CPRA) where the pump pulse is chirped and leads to spatiotemporal distributed gain, which exhibits superradiant scaling in the linear regime, usually associated with the nonlinear pump depletion and Compton amplification regimes. CPRA has the potential to serve as a high-efficiency high-fidelity amplifier/compressor stage
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