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991.
K Wilhelm P Mitchell A Sengoz I Hickie H Brodaty P Boyce 《Canadian Metallurgical Quarterly》1994,28(1):23-33
The clinical characteristics and treatment outcome of a series of 107 patients referred to a mood disorders unit with an episode of "treatment resistant" Major Depression are reviewed. Subjects were categorised by diagnosis (into melancholic and non-melancholic subtypes) and by adequacy of previous treatment. At subsequent review (mean period of 37.5 months) these patients were re-assessed both in terms of outcome and which treatments had been considered to be most effective. Forty one percent of the patient group were fully recovered and a further 43% were partially improved. Different treatments were considered effective for melancholic and non-melancholic sub-types. 相似文献
992.
A bubble surfactometer was used to measure the surface tension of an aqueous suspension of surfactant TA as a function of bubble area over a range of cycling rates and surfactant bulk concentrations. Results of the surface tension-interfacial area loops exhibited a rich variety of phenomena, the character of which varied systematically with frequency and bulk concentration. A model was developed to interpret and explain these data and for use in describing the dynamics of surface layers under more general circumstances. Surfactant was modeled as a single component with surface tension taken to depend on only the interfacial surfactant concentration. Two distinct mechanisms were considered for the exchange of surfactant between the bulk phase and interface. The first is described by a simple kinetic relationship for adsorption and desorption that pertains only when the interfacial concentration is below its maximum equilibrium value. The second mechanism is "squeeze-out" by which surfactant molecules are expelled from an interface compressed past a maximum packing state. The model provided good agreement with experimental measurements for cycling rates from 1 to 100 cycles/min and for bulk concentrations between 0.0073 and 7.3 mg/ml. 相似文献
993.
Carrie C. Wall Frank E. Muller-Karger Mitchell A. Roffer Wensheng Yao 《Remote sensing of environment》2008,112(6):2963-2976
Two algorithms designed to detect deepwater oceanic features and arbitrary edge profiles were tuned to automatically delineate fronts in coastal waters off west-central Florida using satellite-derived sea surface temperature (SST), chlorophyll-a concentration (Chl), normalized water-leaving radiance (nLw), and fluorescence line height (FLH) images during select periods in the spring and fall of 2004 and 2005. The dates correspond to recreational king mackerel, Scomberomorus cavalla, tournaments. A histogram-based algorithm was useful to detect coastal surface SST, nLw, and FLH fronts, specifically. A gradient-based algorithm, with a smaller kernel box of 3 × 3 pixels, best identified nearshore (< 10 m depth) features in Chl images at the mouth of Tampa Bay, but was less effective for fronts farther offshore where gradients were weaker. Local winds and tide levels estimated from a coastal observing buoy, and bathymetric gradients were examined to help understand the factors that influenced front formation and stability. Periods of strong and variable winds led to front movement of up to 10 km per day or dissipation within 2-3 days in over 80% of the fronts detected in SST, Chl, nLw, and FLH imagery. Short episodes of less variable wind velocities typically led to more stable and stationary fronts, within 3-5 km, for up to four days. The occurrence of fronts closely associated with the coastal bathymetry, namely at the 20 m and 30 m isobaths, was significantly higher in the fall SST imagery and in the spring Chl imagery. Fall SST fronts related to bathymetric gradients likely resulted from progressive cooling of the water with depth. Stronger Chl and nLw443 gradients at the mouths of estuaries in the fall compared to the spring were attributed to increased precipitation and periods of stronger winds or tides. The FLH imagery was most useful in delineating coastal algal blooms. The automatic front detection techniques applied here can be an important tool for resource managers to track coastal oceanographic features daily, over synoptic spatial scales. 相似文献
994.
When a solution of blood plasma and sodium alginate (protein: polysaccharide ratio 3:1) was extruded into coagulating baths of calcium chloride there was a rapid increase in shear strength of the fibre bundles with a rise in salt concentration up to 3% calcium chloride. Above this concentration no further increase in shear strength was observed. The ratio of plasma protein to alginate was between 0·84 and 1·1 in all tows produced from unbuffered calcium chloride baths.
Extruding the dope into 5% calcium chloride baths of pH values between 2 and 8 indicated that fibre strength was independent of pH in the range 4 to 8. Below pH 4 the tows rapidly decreased in shear strength to a minimum at pH 3·5. Decreasing the pH further led to an increase in fibre strength as acid denaturated protein coprecipitated with the polysaccharide. The ratio of plasma to alginate in the tows was around 1·0 for pH values above 3·5, rapidly increasing to 2·8 at pH 2·0. 相似文献
995.
996.
Thomas Mitchell 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(12):2057-2070
This paper discusses the subject of automatic evolutionary sound matching: systems in which evolutionary algorithms are used to automatically derive the parameters of a synthesiser to produce a sound that matches a specified target sound. The paper describes prior work and identifies the principal causes of match inaccuracy, which are often due to optimiser limitations as a result of search space problem difficulty. The components of evolutionary matching systems contributing to problem difficulty are discussed and suggestions as to how improvements can be made through problem simplification or optimiser sophistication are considered. Subsequently, a novel clustering evolution strategy is presented which enables the concurrent optimisation of multiple distinct search space solutions, intended for the purposes of sound matching with standard frequency modulation (FM) synthesisers. The algorithm is shown to outperform standard multi-membered and multi-start (1?+?1) evolution strategies in application to different FM synthesis models for static and dynamic sounds. The comparative study makes use of a contrived matching method, which ensures that results are not affected by the limitations of the matching synthesiser. 相似文献
997.
Khashayar Khoshmanesh Sara Baratchi Francisco J. Tovar-Lopez Saeid Nahavandi Donald Wlodkowic Arnan Mitchell Kourosh Kalantar-zadeh 《Microfluidics and nanofluidics》2012,12(1-4):597-606
Dielectrophoresis, the induced motion of dielectric particles in non-uniform electric fields, enables the separation of suspended bio-particles based on their dimensions or dielectric properties. This work presents a microfluidic system, which utilises a combination of dielectrophoretic (DEP) and hydrodynamic drag forces to separate Lactobacillus bacteria from a background of yeasts. The performance of the system is demonstrated at two operating frequencies of 10?MHz and 100?kHz. At 10?MHz, we are able to trap the yeasts and bacteria at different locations of the microelectrodes as they experience different magnitudes of DEP force. Alternatively, at 100?kHz we are able to trap the bacteria along the microelectrodes, while repelling the yeasts from the microelectrodes and washing them away by the drag force. These separation mechanisms might be applicable to automated lab-on-a-chip systems for the rapid and label-free separation of target bio-particles. 相似文献
998.
Handelsman Mitchell M.; Gottlieb Michael C.; Knapp Samuel 《Canadian Metallurgical Quarterly》2005,36(1):59
This article presents an approach to graduate (and professional) training that views becoming an ethical psychologist as an acculturation process. J. W. Berry's (1980, 2003) model of acculturation strategies is used as a framework for understanding ethical acculturation, a developmental process during which students can use several types of adaptation strategies. Students enter training with their own moral value traditions and concepts but are confronted with new ethical principles and rules, some of which may be inconsistent with their ethics of origin. The article explores several applications of the framework to ethics courses, practicum supervision, and other areas of training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
An experimental technique has recently been developed to characterize reactive metals, including plutonium (Pu) and cerium, using electron backscatter diffraction (EBSD). Microstructural characterization of Pu and its alloys by EBSD had been previously elusive primarily because of the extreme toxicity and rapid surface oxidation rate associated with Pu metal. The experimental technique, which included ion-sputtering the metal surface using a scanning Auger microprobe (SAM) followed by vacuum transfer of the sample from the SAM to the scanning electron microscope (SEM), used to obtain electron backscatter diffraction Kikuchi patterns and orientation maps for a Pu-gallium alloy is described and the initial microstructural observations based on the analysis are discussed. The phase transformation behavior between the δ (face-centered cubic) and ε (body-centered-cubic) structures is explained by combining the SEM and EBSD observations. 相似文献
1000.
Bard K. Dewey B. Hsu M.-T. Mitchell T. Moody K. Rao V. Rose R. Soreff J. Washburn S. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2007,95(3):530-554
IBM's high-performance microprocessor designs leverage internally developed electronic design automation tools to create high-frequency, power efficient, and robust microprocessors. This paper describes some of the tools employed in the custom circuit design methodology in IBM. The tools described include a transistor-level block-based static timer, a static noise analysis methodology, and a transistor width tuner that optimizes performance and area. We also describe the application of electrical rule checking used to enforce consistent design practices. Finally, we discuss a macro extraction tool that determines parasitic resistance and capacitance of interconnect from a layout 相似文献