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81.
A majority of monoclonal antibodies (mAbs) raised against soluble oligomeric human immunodeficiency virus type 1 isolate IIIB (HIV-1IIIB) envelope (env) glycoprotein reacted with conformational epitopes within the gp120 or gp41 subunits. Of 35 mAbs directed against gp41, 21 preferentially reacted with oligomeric env. A subset of these mAbs reacted only with env oligomers (oligomer-specific mAbs). In contrast, only 1 of 27 mAbs directed against the gp120 subunit reacted more strongly with env oligomers than with monomers, and none were oligomer-specific. However, 50% of anti-gp120 mAbs preferentially recognized monomeric env, suggesting that some epitopes in gp120 are partially masked or altered by intersubunit contacts in the native env oligomer. Two mAbs to oligomer-dependent epitopes in gp41 neutralized HIV-1IIIB and HIV-1SF2, and binding of these mAbs to env was blocked by preincubation with HIV-1-positive human serum. Thus, immunization with soluble, oligomeric env elicits antibodies to conserved, conformational epitopes including a newly defined class of neutralizing antibodies that bind to oligomer-specific epitopes in gp41, and may also minimize the production of antibodies that preferentially react with monomeric env protein.  相似文献   
82.
Tackifier dispersions used in pressure‐sensitive adhesives are made by phase inverting an aqueous rosin ester emulsion. The recipe also includes rosin acid and potassium hydroxide which react to form a surfactant. The amount of surfactant available plays a key role in determining dispersion properties. As the surfactant concentration increases, the point of phase inversion is delayed to larger dispersed phase concentrations. This also results in excess dispersant in the liquid phase and a narrower particle size distribution, even though the droplet size remains relatively unchanged.  相似文献   
83.
Abstract:  Accurate short-term prediction of travel speed as a proxy for time is central to many Intelligent Transportation Systems, especially for Advanced Traveler Information Systems and Advanced Traffic Management Systems. In this study, we propose an innovative methodology for such prediction. Because of the inherently direct derivation of travel time from speed data, the study was limited to the use of speed only as a single predictor. The proposed method is a hybrid one that combines the use of the empirical mode decomposition (EMD) and a multilayer feedforward neural network with backpropagation. The EMD is the key part of the Hilbert–Huang transform, which is a newly developed method at NASA for the analysis of nonstationary, nonlinear time series. The rationale for using the EMD is that because of the highly nonlinear and nonstationary nature of link speed series, by decomposing the time series into its basic components, more accurate forecasts would be obtained. We demonstrated the effectiveness of the proposed method by applying it to real-life loop detector data obtained from I-66 in Fairfax, Virginia. The prediction performance of the proposed method was found to be superior to previous forecasting techniques. Rigorous testing of the distribution of prediction errors revealed that the model produced unbiased predictions of speeds. The superiority of the proposed model was also verified during peak periods, midday, and night. In general, the method was accurate, computationally efficient, easy to implement in a field environment, and applicable to forecasting other traffic parameters.  相似文献   
84.
The Task Force on the Employment of Experimental Psychologists in Industry, formed in 1982, conducted 3 surveys to assess the roles of traditionally trained psychologists in nonacademic research settings. The surveyed groups were 209 psychology department chairs, 46 recent recipients of PhDs who had taken nonacademic jobs, and approximately 60 industrial employers at managerial levels. Findings indicate the need for (1) changes in attitude and style in graduate training, (2) course work to relate to industry, (3) increases in internships and practica offered, and (4) strong positive relations between industry and academic psychology. Objectives and recommendations related to needs are offered. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
The current paper considers dynamic production scheduling for manufacturing systems producing products with deep and complex product structures and complicated process routings. It is assumed that manufacturing and assembly processing times are deterministic. Dynamic scheduling problems may be either incremental (where the schedule for incoming orders does not affect the schedule for existing orders) or regenerative (where a new schedule is produced for both new and existing orders). In both situations, a common objective is to minimize total costs (the sum of work-in-progress holding costs, product earliness and tardiness costs). In this research, heuristic and evolutionary-strategy-based methods have been developed to solve incremental and regenerative scheduling problems. Case studies using industrial data from a company that produces complex products in low volume demonstrate the effectiveness of the methods. Evolution strategy (ES) provides better results than the heuristic method, but this is at the expense of significantly longer computation times. It was found that performing regenerative planning is better than incremental planning when there is high interaction between the new orders and the existing orders.  相似文献   
86.
87.
Phase transformation, microstructure development and mechanical properties of 2.45 GHz microwave-sintered silicon nitride (Si3N4) with lithium yttrium oxide (LiYO2) and zirconia (ZrO2) sintering additives were investigated. It was found that α to β phase transformation completed at a lower temperature of 1500 °C. Scanning electron microscopy (SEM) micrographs revealed a bimodal microstructure with a large number of elongated β-Si3N4 grains in addition to smaller grains. Surface residual porosity was observed in all sintered samples due to selective localized over heating of grain-boundary glassy phase. The high aspect-ratio of β-Si3N4 grains exhibited significant crack deflection, debonding and pull-out. It was observed that Vickers hardness and indentation fracture toughness increased with increasing sintering temperature.  相似文献   
88.
This article reports on the psychometric properties of a newly constructed Hawaiian Culture Scale—Adolescent Version. A total of 2,272 Native Hawaiian and 1,170 non-Hawaiian adolescents were administered this 50-item inventory that measures the source of learning the Hawaiian way of life, how much Hawaiian beliefs are valued and important to maintain, how much non-Hawaiian beliefs are valued, Hawaiian blood quantum, and specific cultural traditions (seven subscales?=?Lifestyles, Customs, Activities, Folklore, Causes—Locations, Causes—Access, and Language Proficiency). The results strongly supported the internal consistency and validity of the measures for both the Hawaiian and non-Hawaiian groups. On the basis of the demographic data, partial support was offered for cross-cultural theories of ethnic identity. More consistent support was found for multiculturalism in Hawai'i's adolescents. Further research is needed to link these measures with indicators of psychological adjustment (e.g., depression, anxiety, substance use). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Factors affecting the electrical resistivity of soybean oil methyl ester (which is important in some industrial applications) were investigated by the addition of polar constituents [free fatty acids (FFA), water, phospholipids, monoglyceride, sterol, tocopherol, peroxides, and β-carotene] to aluminapurified soybean oil methyl ester (APSBOMe). Investigation of measuring conditions showed that reproducible results were obtained when the potential was greater than 25 V, and the charging time was greater than 10 s. The resistivity of APSBOMe increased logarithmically as temperature decreased linearly. FFA had little effect on resistivity. Saturation with water lowered the resistivity of APSBOMe much more than that of alumina-purified soybean oil (APSBO). Phospholipids reduced the resistivity significantly when added to dry ester, but the addition of water affected the resistivity of the samples containing phospholipids only slightly. Monoglyceride, sterol, tocopherol, and hydroperoxide affected the resistivity of dry methyl ester similarly, but only monoglyceride showed a significant synergistic effect with water. Diacylperoxide and β-carotene had little effect on the resistivity of the ester.  相似文献   
90.
Seven types of Swiss cheese-like products were made by recombining skim milk with various fat sources: higholeic sunflower oil (HOSO), milk fat, randomized milk fat, HOSO with commerical short-chain fatty acids (C4−C10) (SCFA) interesterified at 100 and 120% of the levels in the milk fat, HOSO with interesterified milk fat SCFA, and HOSO with dissolved free SCFA. Sensory, chemical, and physical analyses were conducted to evaluate the flavor and texture of the cheeses. All cheeses made from HOSO with interesterified SCFA were not significantly different from milk fat controls in typical Swiss flavor and volatile flavor. HOSO with interesterified SCFA scored significantly higher in these flavors than unmodified HOSO. Swiss flavor was positively correlated with sweetness (0.805), volatile flavor (0.737), caramelized flavor (0.703), non-fat solids (0.663), and SCFA (0.639), and negatively correlated with fat (−0.645) and salt (−0.482) content. A linear regression model was established for typical Swiss flavor that included fat, salt, titratable acidity, and medium- and long-chain fatty acids as variables (R 2=0.91). Instrumental texture profile analysis indicated no differences among the treatments in texture atributes except cohesiveness. The production of a good-flavored Swiss cheeselike product from HOSO with interesterified SCFA appears to be commercially feasible.  相似文献   
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