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131.
Water Resources Management - The present study considered the impacts of global climate model (GCM) selection in the Couple Model Intercomparison Phase 5 (CMIP5) scenarios on the low-flow... 相似文献
132.
Y Imai S Sone S Serizawa SH Bae N Imai M Hasegawa K Yamashita 《Canadian Metallurgical Quarterly》1995,55(8):562-568
The magnetic resonance (MR) imaging and computed tomography (CT) findings in four patients (five kidneys) with non-Hodgkin's lymphoma involving the kidneys and perirenal spaces are presented. The patterns of disease in each case were as follows: bilateral renal nodules, infiltration in the perirenal space, infiltration in the perirenal space with renal involvement, and direct invasion from contiguous retroperitoneum. On plain CT, the lesions showed slight hyperdensity (three kidneys) and isodensity (two kidneys) as compared with normal renal parenchyma. But all lesions appeared as hypodense masses with more definite margins after contrast enhancement. MR imaging findings showed iso- or slight hypointense masses on T1-weighted images and definite hypointense masses on T2-weighted images as compared with the signal intensity of the renal cortex. Dynamic imaging and conventional delayed T1-weighted imaging following Gd-DTPA injection showed no significant enhancement of the lesions. In comparison with contrast enhanced CT, despite its poorer resolution, T2-weighted MR imaging showed nearly the same accuracy in the evaluation of number and extent of the lesions without contrast medium administration. MR imaging was also useful to evaluate the patency of vessel lumen surrounded by tumor mass and to determine the location and extent of huge lesions by its multiplanar imaging capabilities. 相似文献
133.
SH Ahn DW Seo YK Ko DS Sung GU Bae JW Yoon SY Hong JW Han HW Lee 《Canadian Metallurgical Quarterly》1998,21(6):657-663
OBJECTIVE: To identify factors associated with the initiation of breast-feeding in a predominantly Puerto Rican population living in inner-city Hartford, Conn. DESIGN: Retrospective study of 144 Latino women (mean +/- standard deviation age = 26.3 +/- 5.7 years) with children at least 1 year old but younger than 6 years old (mean +/- standard deviation age = 3.0 +/- 1.2 years) at the time of the survey. Women were recruited from agencies sponsoring health programs for mothers and children. They were interviewed in their homes (69%) or at the Hispanic Health Council, Hartford, Conn (31%). SUBJECTS/SETTING: Low-income Latino women who had at least 1 preschooler at the time of the interview. The women lived in inner-city Hartford, and the overwhelming majority were Puerto Rican and received welfare assistance and food stamps. Seventy-eight percent of the women chose to be interviewed in Spanish; the other 22% were interviewed in English. STATISTICAL ANALYSES: Explanatory variables that related to breast-feeding initiation (P < or = .2) in bivariate chi 2 analyses were entered into a multivariate logistic regression model that was reduced using backward stepwise elimination procedures. RESULTS: Multivariate analyses indicated that breast-feeding the previous child, shorter length of maternal residence in the United States, not receiving prenatal bottle-feeding advice, more recent birth, and higher birth weight were positively associated with breast-feeding initiation. A major reason for choosing not to breast-feed was that women felt socially uncomfortable doing it. APPLICATIONS: Breast-feeding initiation was more likely in Latino women who received prenatal breast-feeding counselling and postpartum support. Mothers of low-birth-weight infants and women breast-feeding for the first time may need additional help. These findings can be used by programs like the Special Supplemental Nutrition Program for Women, Infants, and Children to increase breast-feeding initiation. 相似文献
134.
Polysaccharides extracted from Pleurotus eryngii were chemically modified by sulfation and the effects on the structural and biological properties of the polysaccharides were investigated as a function of the degree of sulfation. 13C NMR spectroscopy demonstrated that polysaccharides from P. eryngii were mainly composed of β-(1 → 3)-glucans with β-(1 → 6) branches. The structure of the sulfated polysaccharides was confirmed by FT-IR and their degree of substitution (DS) was determined to be 0.12–0.92. When P. eryngii polysaccharides were sulfated they were shown to be effective in inhibiting cancer cell growth in a dose-dependent way. Furthermore, their DPPH radical quenching effects were improved with increasing degree of sulfation. Thus, it seemed that the chemical modification of P. eryngii polysaccharides by sulfation effectively enhanced their potential biological properties. 相似文献
135.
In a previous study we modified a double lattice model by introducing a new interaction parameter, which improved the mathematical approximation defect, and gave a new expression for the Helmholtz energy of mixing. In the model the universal constants Cβ and Cγ in the primary lattice were determined by comparing them with literature Monte Carlo simulation data, which is the only case for r1 = 1 and r2 = 100 (case I). In this study we introduce new universal constants, Cβ and Cγ, as a function of the chain length of a polymer in a solvent (case II) by comparing them with other literature simulation data for various polymer chain lengths. The proposed model is compared with polymer–solvent systems. In an upper critical solution temperature phase behavior the theoretical results of case II were improved over those of case I. However, in a lower critical solution temperature phase behavior those of case I were not very sensitive to Cβ and Cγ. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2627–2633, 1999 相似文献
136.
Taeho Kim Taehwan Ahn Byeonggeon Bae Jae Jun Jeong Byongjo Yun Kyungdoo Kim 《American Institute of Chemical Engineers》2019,65(6):e16591
This article proposes a new single optical fiber probe (OFP) sensor method for measuring local droplet parameters such as droplet fraction, droplet velocity, and droplet diameter. To this end, we developed a stretched conical optical fiber probe (SC-OFP) sensor that minimizes the wetting of the sensing tip at a high droplet velocity, a discrimination algorithm based on the first and second derivatives of the output of the raw signal of the OFP sensor, and a method that uses neural network training to determine local droplet velocity independently of droplet size. In the experiments conducted, the developed SC-OFP sensor measured local droplet velocity with a mean absolute percentage error (MAPE) smaller than 4.1% for velocities ranging from 2 to 32 m/s, and droplet diameter with a MAPE smaller than 4.9% for diameters ranging from 0.29 to 1.78 mm. 相似文献
137.
Eunjoo Bae Hee-Jin Park Jaeyong Yoon Younghun Kim Kyunghee Choi Jongheop Yi 《Korean Journal of Chemical Engineering》2011,28(1):267-271
Silver nanoparticles (AgNPs), potent antibiotic materials, have been found to cause cell-membrane damage and produce reactive oxygen species (ROS). The resultant structural change in the cell-membrane could cause an increase in cell permeability of silver ions and AgNPs. To address this issue further, in-vivo and in-vitro cytotoxicity testing of as-made nanomaterials was conducted to quantify and assess their nanotoxicity. Considering the behavior of AgNPs in the environment, toxicity may be reflected by differences in their physicochemical properties (size, agglomeration rate, adsorption properties on humic acid) dependency and toxicity depression. Therefore, we investigated the effect of the cellular uptake of AgNPs with the kinetics of agglomeration and adsorption. The amount of agglomerated and adsorbed AgNPs with sizes of <14 nm was higher than that for AgNPs with sizes of 90 and 140 nm. For 90 and 140 nm sized AgNPs, adsorption was more significant than agglomeration. It is noteworthy that the normal concept that smaller sized AgNPs are taken up more readily may be in error in cases of interactions of abiotic factors. 相似文献
138.
139.
Jin Woo Bae Tae Uk Yang Gi Joon Nam Gun Joo Lee Byeong-Uk Nam Jae Young Jho 《Polymer Bulletin》2011,67(4):729-740
Ethylene vinylacetate (EVA) copolymer-based nanocomposites with maleic anhydride-grafted ethylene-vinylacetate (EVAgMA) and
organically modified clay (o-clay) were prepared in a twin screw extruder by following a two-step melt compounding method.
EVAgMA/o-clay masterbatches with various clay contents up to 50 wt% were examined, after which the masterbatch with the highest
clay content was melt compounded with EVA for the preparation of EVA/o-clay nanocomposites containing specific amounts of
clay. Further morphological dispersion of the clay particles by highly polar EVA and shearing was confirmed in the EVA/o-clay
nanocomposites by X-ray diffraction (XRD) and transmission electron microscopy (TEM). These morphologies led to increased
thermal properties in air as well as a considerable decrease in heat release rate (HRR). EVA/o-clay/MDH nanocomposites were
also prepared using a high clay-bearing masterbatch to confirm the synergistic flame retardancy of clay as a co-additive in
EVA/MDH composites. EVA/o-clay/MDH nanocomposites prepared by substituting o-clay for MDH showed significantly lower and wider
HRR during combustion compared to EVA/MDH composite. 相似文献
140.
Suk-Hwan Kang Jae-Hong Ryu Jin-Ho Kim P. S. Sai Prasad Jong Wook Bae Joo-Young Cheon Ki-Won Jun 《Catalysis Letters》2011,141(10):1464-1471