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31.
Domestic violence is a significant public health issue affecting women. Numerous medical organizations have recommended that routine screening of women be conducted to assist in the prevention, identification, and care for victims of violence. This article examines the scope of domestic violence in women, reviews ways to recognize abuse, examines the potential impact of abuse upon health and discusses the management of victims.  相似文献   
32.
The form I coding region of Shigella sonnei was cloned and shown to have an operon-like rfb organization. It was found that the 11.0 kb HindIII-XbaI fragment of pHH201 encoding the form I antigen contains 10 contiguous open reading frames (ORF), ORF1 to ORF10. Deletions from either end of pHH201, within ORF1 or ORF10, eliminated form I expression. ORF1 and ORF2 share significant nucleic and amino acids homologies to two ORF's of the Salmonella typhi Vi antigen genes. ORF5 in pHH201 is identical to IS630. pHH2064, derived from pHH201, lacks the IS630 element and can stably express the form I antigen inE. coli HB101. However, pHH2064 is structurally unstable in a S. sonnei form II host. This indicates that the presence of the IS630 gene within the S. sonnei rfb operon may be necessary for the stability of form I expression in S. sonnei. This finding is substantiated by the observation that all virulent S. sonnei isolates examined in this study retained the IS630 element within their rfb operon.  相似文献   
33.
A newly proposed method, called the current-dependent hot-electron stress, is used to study InGaP-gated and AlGaAs-gated low noise PHEMT devices with different drain currents at high drain voltages. The impact ionization between gate and drain is the major mechanism affecting devices during hot-electron stressing, which are excited by the high gate-to-drain electric fields. However, the measure of the effects of the impact ionization related to the drain current during hot-electron stressing is less discussed in the published literatures. In this work, the designed hot-electron stressed conditions, which are related to the different drain currents, are used to demonstrate the influence of drain currents in hot-electron stresses and, furthermore, to estimate and compare InGaP-gated with AlGaAs-gated PHEMTs.  相似文献   
34.
CuInSe2 thin films were prepared on Mo-coated glass substrates using pulse electrodeposition with an aqueous solution containing sodium dodecyl sulfate (SDS) as an additive. The effect of SDS on the electrochemistry mechanism that inhibits secondary phases (CuxSey) was examined using cyclic voltammetry, which indicated that SDS can inhibit the reduction of Cu2+ and H2SeO3 and prohibit the formation of secondary phases. Scanning electron microscopy and atomic force microscopy revealed that the cracks and roughness of CuInSe2 films decreased considerably after adding SDS into the electrolyte. The suppression of secondary phases was also observed using X-ray diffraction and Raman spectroscopy. The optical bandgap values of the CuInSe2 films were measured using a UV–vis–NIR spectrophotometer; the bandgap values of the films deposited in the electrolyte with 0 and 1 mM SDS were approximately 0.96 and 1.05 eV, respectively. As expected, based on these differences, the CuInSe2 solar cell with the Al/AZO/i-ZnO/CdS/CuInSe2/Mo/glass structure derived from precursor film deposited in an electrolyte containing SDS demonstrated greater efficiency (η = 2.51 %) than that of the cell derived from precursor film deposited in an electrolyte without SDS (η = 0.63 %).  相似文献   
35.
36.
Turbulent flow of kerosene, which is driven by a rotating disk in a closed chamber, shows significant drag reduction when tiny amount of an oil-soluble polyisobutylene (PIB) was added. Effect of experimental parameters such as Reynolds number (Re) and temperature on the time dependence of drag reduction was investigated, in which turbulent drag reduction efficiency for the PIB–kerosene solution was found to decrease with time due to mechanical degradation of the polymer chains induced by severe turbulent flow. The change in drag reduction efficiency was fitted well with two model equations of Brostow and our proposed model as a function of time.  相似文献   
37.
In this paper, we introduce a robust monolithic integration technique for fabricating photonic integrated circuits comprising optoelectronic devices (e.g., surface-illuminated photodetectors, waveguide quantum-well modulators, etc.) that are made of completely separate epitaxial structures and possibly reside at different locations across the wafer as necessary. Our technique is based on the combination of multiple crystal growth steps, judicious placement of epitaxial etch-stop layers, a carefully designed etch sequence, and self-planarization and passivation steps to compactly integrate optoelectronic devices. This multigrowth integration technique is broadly applicable to most III-V materials and can be exploited to fabricate sophisticated, highly integrated, multifunctional photonic integrated circuits on a single substrate. As a successful demonstration of this technique, we describe integrated photonic switches that consume only a 300 /spl times/300 /spl mu/m footprint and incorporate InGaAs photodetector mesas and InGaAsP/InP quantum-well modulator waveguides separated by 50 /spl mu/m on an InP substrate. These switches perform electrically-reconfigurable optically-controlled wavelength conversion at multi-Gb/s data rates over the entire center telecommunication wavelength band.  相似文献   
38.
As an increasingly adopted storm-water best management practice (BMP) to remedy hydrology and water quality impairment from urban development, bioretention facilities need rigorous investigation to quantify performance benefits and to allow design improvements. This study examines water quality improvements [total arsenic, total cadmium, chloride, total chromium, total and dissolved copper, E. coli, fecal coliform, lead, mercury, nitrogen species, oil and grease, phosphorus, total organic carbon (TOC), total suspended solids, and total zinc] via monitoring for a 15-month period at two bioretention cells in Maryland. Both bioretention cells effectively removed suspended solids, lead, and zinc from runoff through concentration reduction. Runoff volume reduction promotes pollutant mass removal and links BMP water quality benefits with hydrologic performance. From a load perspective (kg/ha?year), all but TOC at one cell showed pollutant reduction. Bioretention effluents exhibited good water quality for all significant pollutants except for nitrate, copper, and phosphorus in one cell, the latter two of which may be attributed to media organic matter dissolution. Copper dissolved/particulate analyses showed that significant changes in copper speciation behavior result from transport through the bioretention media.  相似文献   
39.
Enhanced polarisation self-switching is observed in a vertical-cavity surface-emitting laser by involving gain saturation due to transverse mode competition. Switching between orthogonal polarisations is triggered by a quarter-wave plate external cavity and does not change the total output power  相似文献   
40.
A novel microstrip bandpass filter with three types of rectangular, photonic bandgap (PBG) loops on a middle layer was designed and demonstrated using a full-wave electromagnetic (EM) simulator, with the predicted results verified by experiment. This investigation presents the configurations of conventional parallel-coupled 2 GHz filters with arid without a PBG. The middle-layer of PBG loops adds an extra stopband-rejection mode to filter stop-band; and it provides attenuation in excess of 25 dB at the second, third, and fourth harmonics, thus demonstrating that superior stopband characteristics at high frequency can be obtained using the proposed PBG loops in microwave filters.  相似文献   
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