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131.
There is an increasing need to develop powerful techniques to improve biomedical pattern discovery and visualization. This paper presents an automated approach, based on hybrid self-adaptive neural networks, to pattern identification and visualization for biomolecular data. The methods are tested on two datasets: leukemia expression data and DNA splice-junction sequences. Several supervised and unsupervised models are implemented and compared. A comprehensive evaluation study of some of their intrinsic mechanisms is presented. The results suggest that these tools may be useful to support biological knowledge discovery based on advanced classification and visualization tasks. 相似文献
132.
Capillary electrophoresis for the analysis of biopolymers 总被引:5,自引:0,他引:5
133.
The capabilities and limitations of rainbow refractometry, specifically the minimum measurable droplet size and the errors in the refractive index (temperature), have been studied. We evaluate what we believe is a new method of indirectly applying the Lorenz-Mie theory to rainbow refractometry. The results show that this new method reduces the errors and eliminates the biases that may occur if the Airy theory is used. A more precise method to filter the high-frequency oscillations associated with the measurement signals was developed. Finally, it was discovered that the errors associated with rainbow refractometry are such that a single droplet measurement is unreliable. A mean refractive index should be determined on the basis of multiple droplet measurements. 相似文献
134.
135.
Nizhnikov Michael E.; Varlinskaya Elena I.; Petrov Evgeniy S.; Spear Norman E. 《Canadian Metallurgical Quarterly》2006,120(2):267
Toward understanding why infant rats ingest high levels of ethanol without initiation procedures, the authors tested effects of mu and kappa receptor antagonists on ethanol reinforcement in neonatal rats. After an intracisternal injection of CTOP (mu antagonist), nor-Binaltorphimine (kappa antagonist), or saline, newborn (3-hr-old) rats were given conditioning pairings of an odor with intraorally infused ethanol or a surrogate nipple with ethanol administered intraperitoneally (to minimize ethanol's gustatory attributes). In each case, these opioid antagonists reduced or eliminated ethanol's reinforcement effect. The same effects occurred with saccharin as the reinforcer in olfactory conditioning. The results imply that activation of mu and kappa receptors, apparently acting jointly, is necessary for reinforcement or that antagonists of this activity impair basic conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Are there sex differences in criteria for sexual relationships? The answer depends on what question a researcher asks. Data suggest that, whereas the sexes differ in whether they will enter short-term sexual relationships, they are more similar in what they prioritize in partners for such relationships. However, additional data and context of other findings and theory suggest different underlying reasons. In Studies 1 and 2, men and women were given varying "mate budgets" to design short-term mates and were asked whether they would actually mate with constructed partners. Study 3 used a mate-screening paradigm. Whereas women have been found to prioritize status in long-term mates, they instead (like men) prioritize physical attractiveness much like an economic necessity in short-term mates. Both sexes also show evidence of favoring well-rounded long- and short-term mates when given the chance. In Studies 4 and 5, participants report reasons for having casual sex and what they find physically attractive. For women, results generally support a good genes account of short-term mating, as per strategic pluralism theory (S. W. Gangestad & J. A. Simpson, 2000). Discussion addresses broader theoretical implications for mate preference, and the link between method and theory in examining social decision processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
Douglas Kevin S.; Herbozo Sylvia; Poythress Norman G.; Belfrage Henrik; Edens John F. 《Canadian Metallurgical Quarterly》2006,3(2):97
Evidence suggests that behavioral aspects of psychopathy are associated with suicidal behavior, whereas the affective and interpersonal aspects are not. The authors tested the robustness of this bifurcated association across 1,711 persons and 12 samples of adult and juvenile criminal offenders, forensic psychiatric patients, and civil psychiatric patients. The authors observed a small but significant partial correlation (.13) between the behavioral/impulsive lifestyle features of psychopathy and suicidality, but no effect for affective/interpersonal features. Several method and sample features (mental disorder; psychopathy and suicidality measurement format) significantly strengthened or weakened this association. The authors conclude that it is not possible to speak of "the" association between psychopathy and suicide, but that this relationship appears to be partially dependent on methodological (i.e., self-report vs. clinician-administered psychopathy measures) and sample composition (i.e., age; mental illness) factors. Recommendations for practice are provided, including that clinicians should not consider psychopathy a buffer against suicidal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
A. Schneider B. Su T. W. Button L. Singleton O. Wilhelmi S. E. Huq P. D. Prewett R. A. Lawes 《Microsystem Technologies》2002,8(2-3):88-92
In this paper results are presented from a range of experiments to explore the feasibility of inserting a ceramic material
PZT (lead zirconium titanate) into different kinds of high-aspect-ratio resist moulds. Polymethylmethacrylate (PMMA) and SU-8
on silicon substrates and free-standing SU-8 membranes with micro-cavities or through-holes (defined by X-ray lithography)
have been used as moulding medium. Processing conditions for the resist materials including pre-bake, exposure, post-bake,
development and stripping have been compared. The advantages of different types of resist mould for the LIGA process has been
evaluated. Additionally a comparison of photosensitivity of PMMA and SU-8 has been carried out. Using a range of load pressures
(5 to 60 MPa), appropriate conditions for PZT embossing into resist moulds have been determined (ensuring minimum void formation
in the final PZT structures). In the final form, SU-8 moulds have been removed by laser ablation. This is the first reporting
of high-aspect-ratio ceramic microstructures fabricated using a combination of SU-8 moulds and PZT embossing.
Received: 10 August 2001/Accepted: 24 September 2001 相似文献
139.
Alemi F Neuhauser D Ardito S Headrick L Moore S Hekelman F Norman L 《The Joint Commission journal on quality improvement》2000,26(2):74-86
BACKGROUND: Continuous quality improvement (CQI) thinking and tools have broad applicability to improving people's lives--in continuous self-improvement (CSI). Examples include weight loss, weight gain, increasing exercise time, and improving relationship with spouse. In addition, change agents, who support and facilitate organizational efforts, can use CSI to help employees understand steps in CQI. A STEP-BY-STEP APPROACH: Team members should be involved in both the definition of the problem and the search for the solution. How do everyday processes and routines affect the habit that needs to change? What are the precursors of the event? Clients list possible solutions, prioritize them, and pilot test the items selected. One needs to change the daily routines until the desired behavior is accomplished habitually and with little external decision. DISCUSSION: CSI is successful because of its emphasis on habits embedded in personal processes. CSI organizes support from process owners, buddies, and coaches, and encourages regular measurement, multiple small improvement cycles, and public reporting. 相似文献
140.
To determine the impact of reducing the current legal limit of 750,000 cells/ml for somatic cell count (SCC) in US market milk, data were examined from 539,577 herd test days for Dairy Herd Improvement herds on test during 1996 and 1997. Somatic cell scores for individual cows were converted to SCC. The SCC for each cow was weighted by milk yield and used to compute herd mean on test day. The mean for each state was derived by weighting herd test-day SCC by herd test-day milk yield. State means were lowest in the West and highest in the Southeast. The percentage of herd test days with an SCC of >750,000 cells/ml ranged from 0 to 14% across states; the mean was 4%. Only 1% of the herd tests were >750,000 cells/ml on 2 consecutive test days. Mean SCC in the United States was 307,100 cells/ml for 1996 and 313,500 cells/ml for 1997. Mean SCC was lower during October through January (280,000 to 300,000 cells/ml) than during July and August (340,000 cells/ml). Herd size and SCC were negatively related; larger herds had lower SCC. Because records of some cows treated with antibiotics were included in the data, herd SCC means likely were higher than corresponding bulk tank SCC. Most herds had test-day SCC that were substantially below legal bulk tank limits and could have met lower limits (e.g., 500,000 cells/ml). 相似文献