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91.
We present a scalable process for the fabrication of slanted carbon nanotube micropillar arrays by inclined metal deposition and capillary self-assembly. Local control of the micropillar angle from vertical to nearly horizontal is achieved, and is explained using a finite element model. These structures may be useful for microscale contacts and anisotropic smart surfaces. 相似文献
92.
This research examined the hypothesis that situational achievement cues can elicit achievement or fun goals depending on chronic differences in achievement motivation. In 4 studies, chronic differences in achievement motivation were measured, and achievement-denoting words were used to influence behavior. The effects of these variables were assessed on self-report inventories, task performance, task resumption following an interruption, and the pursuit of means relevant to achieving or having fun. Findings indicated that achievement priming (vs. control priming) activated a goal to achieve and inhibited a goal to have fun in individuals with chronically high-achievement motivation but activated a goal to have fun and inhibited a goal to achieve in individuals with chronically low-achievement motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
High-throughput method for the production and analysis of large natural product libraries for drug discovery 总被引:6,自引:0,他引:6
Eldridge GR Vervoort HC Lee CM Cremin PA Williams CT Hart SM Goering MG O'Neil-Johnson M Zeng L 《Analytical chemistry》2002,74(16):3963-3971
High-throughput methods were applied to the production, analysis, and characterization of libraries of natural products in order to accelerate the drug discovery process for high-throughput screening in the pharmaceutical and biotechnology industries. Library production integrates automated flash chromatography, solid-phase extraction, filtration, and high-throughput parallel four-channel preparative high-performance liquid chromatography to obtain the libraries in 96- or 384-well plates. Libraries consist of purified fractions with approximately one to five compounds per well. Libraries are analyzed prior to biological screening by a high-throughput parallel eight-channel liquid chromatography-evaporative light scattering detection-mass spectrometry system to determine the molecular weight, number, and quantity of compounds in a fraction. After biological screening, active fractions are rapidly purified at the microgram level and individual compounds are rescreened for confirmation of activity. Structures of active compounds are elucidated by NMR spectroscopy and mass spectrometry. Utilization of a novel microcoil probe allows NMR data to be gathered on 50 microg. As a demonstration, a library was made from the stem bark of Taxus brevifolia. Biological screening in the National Cancer Institute's in vitro panel of three cancer cell lines demonstrates that the process enables the discovery of active anticancer compounds not detected in the flash fractions from which the library originates. 相似文献
94.
William E. Hart 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2005,9(4):225-235
Although real-coded evolutionary algorithms (EAs) have been applied to optimization problems for over thirty years, the convergence properties of these methods remain poorly understood. We discuss the use of discrete random variables to perform search in real-valued EAs. Although most real-valued EAs perform mutation with continuous random variables, we argue that EAs using discrete random variables for mutation can be much easier to analyze. In particular, we present and analyze two simple EAs that make discrete choices of mutation steps. 相似文献
95.
Edzer Huitema Gerwin Gelinck Bas van der Putten Eugenio Cantatore Karel Kuijk Kees Hart Dago De Leeuw 《Journal of the Society for Information Display》2002,10(3):195-202
A 2‐in. active‐matrix display was demonstrated, containing 4096 solution‐processed polymer‐based transistors. By using the polymer‐dispersed liquid‐crystal display (LCD) effect, this results in a reflective, low‐power display with paper‐like contrast. The influence of the transistor parameters on the display performance is analyzed by use of a model for charging and discharging of the pixel capacitors. Good agreement was obtained between the model and the experimental data. Scaling behavior allows estimation of the performance required for transistors in a quarter‐VGA display. These requirements are met by solution‐processed pentacene transistors. 相似文献
96.
Kelly RM Meyer JD Matsuura JE Shefter E Hart MJ Malone DJ Manning MC 《Drug development and industrial pharmacy》1999,25(1):15-20
For certain patients who experience intense vertigo arising from unilateral vestibular lesions, the primary therapy is a vestibular nerve section, an intracranial surgical procedure. One alternative to this treatment is therapeutic ablation of vestibular function on the unaffected side using an ototoxic agent. We prepared a biodegradable sustained-release gel delivery system using sodium hyaluronate that can be administered into the middle ear using only a local anesthetic. The gel contains gentamycin sulfate, the ototoxic agent of choice for treatment of unilateral vestibulopathy, and it exhibits diffusion-controlled release of the drug over a period of hours. The released gentamycin could then diffuse into the inner ear through the round membrane. This represents an important advance over previous formulations, which used only gentamycin sulfate solutions, in that it should allow more careful control of the dose, it should reduce loss of the drug from the middle ear site, and it should maintain intimate contact with the round membrane. By carefully controlling the dose, it should be possible to inhibit vestibular function while minimizing hearing loss. Herein we describe the in vitro release kinetics of gentamycin sulfate from sodium hyaluronate gels and find that the system obeys Fickian behavior. 相似文献
97.
We report a detailed investigation of nonresonant laser-induced thermal acoustics (LITA) for the single-shot measurement of the speed of sound (v(S)) in an oven containing room air. A model for the speed of sound that includes important acoustic relaxation effects is used to convert the speed of sound into temperature. A reference LITA channel is used to reduce uncertainties in v(S). Comparing thermocouple temperatures with temperatures deduced from our v(S) measurements and model, we find the mean temperature difference from 300 to 650 K to be 1% (+/-2sigma). The advantages of using a reference LITA channel are discussed. 相似文献
98.
OBJECTIVE: To determine whether administration of commercially available Escherichia coli antiserum to neonatal foals would affect serum IgG concentration or morbidity and mortality rates during the first 60 days of life. DESIGN: Randomized controlled trial. ANIMALS: 271 neonatal foals on 4 well-managed farms. PROCEDURE: Foals were randomly assigned to a treatment or control group. All foals were allowed to suckle colostrum normally. In addition, treatment-group foals were given E coli antiserum (10 micromilligrams) orally between 0 and 8 hours after birth. Serum samples were obtained between 18 and 36 hours after birth, and serum IgG concentration was determined. Foals were monitored for the first 60 days after birth, and causes of disease or death were recorded. RESULTS: Groups did not differ significantly in regard to breed, sex, month of birth, season of birth, age of dams, parity of dams, duration of gestation, or specific gravity of colostrum before suckling. In addition, groups did not differ significantly in regard to mean serum IgG concentration, prevalence of complete or partial failure of passive transfer of immunity, frequency or causes of disease, or frequency of death from infectious causes. CLINICAL IMPLICATIONS: In this group of foals on well-managed farms, administration of E coli antiserum did not alter serum IgG concentrations or morbidity and mortality rates during the first 60 days of life. 相似文献
99.
KL Syrjala SL Roth-Roemer JR Abrams JM Scanlan MK Chapko S Visser JE Sanders 《Canadian Metallurgical Quarterly》1998,16(9):3148-3157
PURPOSE: To describe the prevalence of sexual difficulties in men and women after marrow transplantation (MT), and to define medical, demographic, sexual, and psychologic predictors of sexual dysfunction 3 years after MT. PATIENTS AND METHODS: Four hundred seven adult MT patients were assessed pretransplantation. Survivors repeated measures of psychologic and sexual functioning at 1 and 3 years posttransplantation. RESULTS: Data were analyzed from 102 event-free 3-year survivors who defined themselves as sexually active. Men and women did not differ in sexual satisfaction pretransplantation. At 1 and 3 years posttransplantation, women reported significantly more sexual dysfunction than men. Eighty percent of women and 29% of men reported at least one sexual problem by 3 years after MT. No pretransplantation variables were significant predictors of 3-year sexual satisfaction for women. For men, pretransplantation variables of older age, poorer psychologic function, not being married, and lower sexual satisfaction predicted sexual dissatisfaction at 3 years (R2=.28; P < .001). Women who were more dissatisfied 3 years after MT did not receive hormone replacement therapy (HRT) at 1 -year posttransplantation and were less satisfied at 1 year, but not pretransplantation (R2=.35; P < .001). CONCLUSION: Sexual problems are significant in the lives of MT survivors, particularly for women. Although HRT before 1 year posttransplantation improves sexual function, it does not ensure sexual quality of life. Intervention for women is needed to apply hormonal, mechanical, and behavioral methods to prevent sexual difficulties as early after transplantation as possible. 相似文献
100.
Bodakian B. Hart F.X. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1994,1(2):181-187
The permittivity and conductivity of beef and chicken samples were measured in the frequency range of 1 Hz to 1 MHz. Differences were observed in these dielectric spectra for commercially purchased, as compared to freshly slaughtered samples. In particular, fresh samples display a greater directional anisotropy in their electrical properties and a smaller, frequency-dependent conductivity. Changes in the dielectric properties are also produced by freezing and cooking procedures. These results indicate that measurement of the low-frequency dielectric properties of meat products could serve as a monitor of their storage and preparation history 相似文献