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71.
Aldridge Jan; Lamb Michael E.; Sternberg Kathleen J.; Orbach Yael; Esplin Phillip W.; Bowler Lynn 《Canadian Metallurgical Quarterly》2004,72(2):304
Ninety 4- to 13-year-old alleged victims of sexual abuse were interviewed by police officers using the National Institute of Child Health and Human Development (NICHD) investigative interview protocol, following which they were shown a human figure drawing and asked a series of questions. The drawing and associated questions elicited an average of 86 new forensically relevant details. They were especially productive with 4- to 7-year-olds, who provided an average of 95 additional details (27% of their total) after the drawing was introduced despite having previously "exhausted" their memories. Information elicited using the drawing may be less accurate, however, because recognition memory prompts predominated, so such drawings should only be introduced late in investigative interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Yael Paran Swetlana A. Adansky-Boldin Raanan Margalit Hadassa Degani 《Israel journal of chemistry》2003,43(1-2):103-114
Diffusion MRI studies revealed specific morphological and physiological properties of MCF7 tumors implanted in the mammary gland of immunodeficient mice. These tumors mimic the histological and pathophysiological properties of human breast cancer in patients. The experiments were conducted by (1) applying varying diffusion gradient strengths, Gd, from 0 to 20 G/cm and a short diffusion time (td = 16 ms) in order to minimize the effect of restriction and exchange of water between the intra- and extracellular compartments, and (2) applying a strong constant gradient and diffusion times up to 96 ms, revealing water restriction and exchange. The normalized signal intensity was plotted against the diffusion weighting factor b , taking into account interaction with the imaging gradients. The curves were analyzed by applying a bi-exponential decay function assuming two exchanging water compartments, with fast and slow diffusion coefficients. The amplitudes and decay constants of the two exponents, a fast and a slow one, were related to the fraction and apparent diffusion coefficients of the extra- and intracellular water, respectively, considering contributions of restriction and exchange. During tumor progression the distribution of the diffusion parameters for the same experimental protocol varied and became less homogeneous. This was predominantly due to variations in the cellularity and increased necrosis. Upon treatment of the tumors with a new anti-estrogenic drug, tamoxifen methiodide, the changes in the diffusion parameters indicated increased cell swelling. Hence, this cytostatic response to treatment was detected before actual cell death was apparent. The potential capacity of diffusion MRI is of high clinical relevance and may help improve the noninvasive diagnosis and followup of treatment of this devastating disease. 相似文献
73.
Yael Miron 《Journal of hazardous materials》1980,3(4):301-321
Experimental thermal analysis and mass spectrometric results indicate that, when heated, monomethylamine nitrate dissociates to form monomethylamine anMonomethylamine, one of the dissociation products, is a flammable gas. In dry air, at room temperature, its lower limit of flammability is 4.9%. Its auPreventing acid build-up and rust formation is important for the safe handling and transport of monomethylamine nitrate. 相似文献
74.
Eli Aghion Yael Gueta Nir Moscovitch Boris Bronfin 《Journal of Materials Science》2008,43(14):4870-4875
A systematic study was carried out to evaluate the effect of up to 2.5% yttrium additions on the properties of Mg–3%Nd alloy
designated for high-temperature gravity casting applications. All the tested alloys were grain-refined by zirconium. The results
show that additions of yttrium significantly improved the tensile yield strength, fatigue strength, and creep resistance while
reducing the ductility. However, other properties such as the ultimate tensile strength and corrosion resistance in 5% NaCl
solution were nearly not affected. The strengthening effect obtained by the yttrium additions is explained in terms of solid-solution
strengthening and due to formation of a ternary phase of Mg–Nd–Y. The improved creep resistance was due to the large solubility
of yttrium in solid-solution magnesium matrix and to the effective creep deformation barriers created by the ternary phase.
The casting performance of the tested alloys in terms of fluidity was similar and no significant effect of the yttrium was
evident 相似文献
75.
UV disinfection of RBC-treated light greywater effluent: kinetics, survival and regrowth of selected microorganisms 总被引:2,自引:1,他引:1
The microbial quality of raw greywater was found to be much better than that of municipal wastewater, with 1.6 x 10(7)cfu ml(-1) heterotrophic plate count (HPC), and 3.8 x 10(4), 9.9 x 10(3), 3.3 x 10(3) and 4.6 x 10(0)cfu 100 ml(-1) faecal coliforms (FC), Staphylococcus aureus sp., Pseudomonas aeruginosa sp. and Clostridium perfringes sp., respectively. Further, three viral indicators monitored (somatic phage, host: Escherichia coli CN(13) and F-RNA phages, hosts: E. coli F+(amp), E. coli K12) were not present in raw greywater. The greywater was treated by an RBC followed by sedimentation. The treatment removed two orders of magnitude of all bacteria. UV disinfection kinetics, survival and regrowth of HPC, FC, P. aeruginosa sp. and S. aureus sp. were examined. At doses up to 69 mW s cm(-2) FC were found to be the most resistant bacteria, followed by HPC, P. aeruginosa sp. and S. aureus sp. (inactivation rate coefficients: 0.0687, 0.113, 0.129 and 0.201 cm2 mW(-1)s(-1), respectively). At higher doses (69-439 mW s cm(-2)) all but HPC (which exhibited a tailing curve) were completely eliminated. Microscopic examination showed that FC self-aggregate in the greywater effluent. This provides FC an advantage at low doses, since the concentration of suspended matter (that can provide shelter from UV radiation) in the effluent was very low. FC, P. aeruginosa sp. and S. aureus sp. did not exhibit regrowth up to 6h after exposure to increasing UV doses (19-439 mW s cm(-2)). HPC regrowth was proven to be statistically significant in un-disinfected effluent and after irradiation with high UV doses (147 and 439 mW s cm(-2)). At these doses regrowth resulted from growth of UV-resistant bacteria due to decreased competition with other bacteria eliminated by the irradiation. 相似文献
76.
Benny Y Manzanera S Prieto PM Ribak EN Artal P 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(6):1538-1544
The human eye is affected by large chromatic aberration. This may limit vision and makes it difficult to see fine retinal details in ophthalmoscopy. We designed and built a two-triplet system for correcting the average longitudinal chromatic aberration of the eye while keeping a reasonably wide field of view. Measurements in real eyes were conducted to examine the level and optical quality of the correction. We also performed some tests to evaluate the effect of the corrector on visual performance. 相似文献
77.
Peritoneal dialysis (PD) is commonly performed by using preprepared dialysis solutions containing glucose, which are thermally treated to achieve commercial sterilization. A series of glucose degradation products (GDPs) are being formed, which react with the tissue during the dialysis procedure, thus baring a negative effect on the patient and the dialysis process. The present study tested the efficacy of ohmic heating as an alternative thermal treatment for continuous sterilization of PD solutions. The process was compared to conventional retort treatment, and GDPs accumulation was measured. Thermal treatments using the ohmic heating system were performed at three temperatures (105, 125, and 150 degrees C) with residence time at each temperature ranging from 0.84 to 12.0 s. The resulting concentrations of glyoxal (GO), methylglyoxal (MGO), and 3-deoxyglucosone (3-DG) in the PD solutions were measured. None of these GDPs were found in PD fluids treated by ohmic heating at 105 degrees C. The concentration of 3-DG, after a standard sterilization treatment (121 degrees C, 20 or 40 min) was one order of magnitude higher (approximately 140 and 242 microM) than after ohmic heating treatment at 125 degrees C. The results of the present study suggest that this technique can be used to produce solutions with much lower content of GDPs. It also demonstrates the advantage of using the ohmic heating technology as a tool for high temperature short time treatment of PD fluids. 相似文献
78.
Daniel S Moran Yuval Heled Yael Arbel Eran Israeli Aharon S Finestone Rachel K Evans Ran Yanovich 《Journal of the International Society of Sports Nutrition》2012,9(1):1-7
Background
We examined the effect of four weeks of ??-alanine supplementation on isometric endurance of the knee extensors at 45% maximal voluntary isometric contraction (MVIC).Methods
Thirteen males (age 23?±?6 y; height 1.80?±?0.05?m; body mass 81.0?±?10.5?kg), matched for pre-supplementation isometric endurance, were allocated to either a placebo (n?=?6) or ??-alanine (n?=?7; 6.4?g·d-1 over 4?weeks) supplementation group. Participants completed an isometric knee extension test (IKET) to fatigue, at an intensity of 45% MVIC, before and after supplementation. In addition, two habituation tests were completed in the week prior to the pre-supplementation test and a further practice test was completed in the week prior to the post-supplementation test. MVIC force, IKET hold-time, and impulse generated were recorded.Results
IKET hold-time increased by 9.7?±?9.4?s (13.2%) and impulse by 3.7?±?1.3 kN·s-1 (13.9%) following ??-alanine supplementation. These changes were significantly greater than those in the placebo group (IKET: t (11)?=?2.9, p ??0.05; impulse: t (11)?=?3.1, p????0.05). There were no significant changes in MVIC force in either group.Conclusion
Four weeks of ??-alanine supplementation at 6.4?g·d-1 improved endurance capacity of the knee extensors at 45% MVIC, which most likely results from improved pH regulation within the muscle cell as a result of elevated muscle carnosine levels. 相似文献79.
Novel sub-millimeter cold-set whey protein isolate (WPI) microgels for the stable immobilization of lipids were prepared by an emulsification/internal gelation technique. Microgels were prepared by the addition of a denatured WPI/lipid primary emulsion (containing a micronized calcium source) into an oil bath with gentle stirring, into which an oil soluble acid was added to liberate calcium and initiate gelling of the whey-based matrices. The efficiency of these matrices to entrap lipids was assessed by comparing to extrusion/externally gelled matrices, where the production process is potentially less destructive, but microgels under 1 mm in diameter are difficult to achieve. The micron-sized (below 100 μm in diameter) internally gelled matrices produced by an optimized process, successfully immobilized incorporated lipids, with greater than 93% retention of lipids, regardless of the investigated manufacturing conditions. Migration of exterior oil, during the O/W/O production process, into the microgels was also avoided. Examination of the micro-structure by scanning electron microscopy revealed voids uniformly distributed throughout the matrix, representative in size (under 0.4 μm) of the original primary emulsion lipid droplets. The study shows relevant feasibility for the stable inclusion of a wide range of sensitive lipophilic bioactive ingredients into these matrices, where the sub-millimeter size of the microgels represents potential for incorporation into a variety of food systems. 相似文献
80.
An important strategy used in the polymer industry in recent years is blending two bio‐based polymers to attain desirable properties similar to traditional thermoplastics, thus increasing the application potential for bio‐based and bio‐degradable polymers. Miscibility of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) with poly(L ‐lactic acid) (PLA) were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Three different grades of commercially available PLAs and one type of PHBV were blended in different ratios of 50/50, 60/40, 70/30, and 80/20 (PHBV/PLA) using a micro‐compounder at 175°C. The DSC and TGA analysis showed the blends were immiscible due to different stereo configuration of PLA polymer and two distinct melting temperatures. However, some compatibility between PHBV and PLA polymers was observed due to decreases in PLA's glass transition temperatures. Additionally, the blends do not show clear separation by SEM analysis, as observed in the thermal analysis. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献