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排序方式: 共有649条查询结果,搜索用时 15 毫秒
131.
In this study, ant colony optimisation (ACO) algorithm is used to derive near‐optimal interactions between a number of single nucleotide polymorphisms (SNPs). This approach is used to discover small numbers of SNPs that are combined into a decision tree or contingency table model. The ACO algorithm is shown to be very robust as it is proven to be able to find results that are discriminatory from a statistical perspective with logical interactions, decision tree and contingency table models for various numbers of SNPs considered in the interaction. A large number of the SNPs discovered here have been already identified in large genome‐wide association studies to be related to type II diabetes in the literature, lending additional confidence to the results.Inspec keywords: genetics, genomics, DNA, polymorphism, molecular biophysics, molecular configurations, ant colony optimisation, decision trees, bioinformatics, diseasesOther keywords: ant colony optimisation, decision tree, contingency table models, gene‐gene interactions, ACO algorithm, near‐optimal interactions, single nucleotide polymorphisms, SNP, genome‐wide association studies, type II diabetes 相似文献
132.
R. Ty Baublits Fred W. Pohlman A. Hayden Brown Jr. Ed J. Yancey Zelpha B. Johnson Palika Dias-Morse 《Journal of food science》2006,71(2):S91-S96
Beef triceps brachii muscles (6 d postmortem; n= 15; muscle sections n= 45) were sectioned into 3rds and allocated to 1 of 3 treatments. The treatments were untreated (CNT), or injected at a 12% pump rate with either tap water‐only (H2O) or a solution comprising tetrasodium pyrophosphate and sodium chloride (TSPP/ NaCl) at 0.4% and 1.0% target final product weight concentrations, respectively. Each muscle (comprising all 3 treatments) was then allocated to 2, 14, or 28 d of vacuum‐packaged 1°C storage. Purge losses during storage were greatest (P < 0.05) for H2O muscles and least (P < 0.05) for TSPP/NaCl muscles. Purge losses also increased (P < 0.05) from 2 d to 14 d of storage. Steaks enhanced with TSPP/NaCl had less (P < 0.05) free water and lower (P < 0.05) cooking losses than either CNT or H2O steaks. Storage duration did not affect (P > 0.05) Warner‐Bratzler shear force (WBS) or sensory tenderness, but juiciness decreased (P < 0.05) with increased storage duration. While storage duration did not impact (P > 0.05) instrumental color characteristics, aerobic plate counts generally increased during storage. The TSPP/NaCl steaks had lower (P < 0.05) WBS values and improved (P < 0.05) sensory tenderness and juiciness characteristics compared with CNT or H2O steaks. While CNT steaks had greater (P < 0.05) L* values (lightness) than TSPP/NaCl steaks, TSPP/NaCl steaks had similar (P > 0.05) oxymyoglobin proportions (630/580 nm) and a* values (redness) as CNT steaks. These results suggest enhancement with TSPP/NaCl can improve triceps brachii yield and palatability characteristics. Increased post‐enhancement storage did not impact or worsened palatability while increasing purge losses, suggesting general deleterious effects of increased postmortem storage for this muscle. 相似文献
133.
134.
CW Hyatt 《Canadian Metallurgical Quarterly》1998,45(3):307-311
BACKGROUND: Hepatitis G virus (HGV) is a blood-borne flavivirus that may cause acute and chronic transfusion-transmitted infections. Patients with complement component 1 (C1) inhibitor (C1-INH) deficiency may acquire blood-borne infections through infusion of plasma concentrates. STUDY DESIGN AND METHODS: Serum samples from 84 patients with C1-INH deficiency (19 who received unmodified C1-INH concentrates, 23 who received steam-heated concentrates, and 42 untreated patients) were tested for HGV RNA and hepatitis C virus (HCV) RNA by a nested polymerase chain reaction (PCR). The samples were also tested for antibodies to the E2 envelope protein of HGV (anti-HGV) and to HCV with enzyme-linked immunosorbent assays. RESULTS: Nine (11%) patients had serum HGV RNA; that is, 7 (17%) of 42 patients previously treated with C1-INH concentrates and 2 of 42 previously untreated patients. HGV RNA was as common in the 19 patients treated with unmodified concentrates as in the 23 given steam-heated concentrates (16 vs. 17%, p = 0.60). Anti-HGV was more common among the recipients of unmodified concentrates than among those given steam-heated concentrates (26 vs. 0%, p = 0.014). HCV RNA was more frequently detected in treated patients than in untreated patients (33 vs. 7%, p = 0.005) and in the 19 recipients of unmodified concentrates than in the 23 treated with steam-heated concentrates (58 vs. 16%, p = 0.003). Only one HGV RNA-seropositive patient had elevated serum aminotransferase activity, compared to 11 with HCV RNA. CONCLUSION: HGV was transmitted by both unmodified and steam-heated concentrates, but it caused persistent viremia in a minority of the cases and was rarely associated with liver disease. 相似文献
135.
136.
Reexamining adaptation and the set point model of happiness: Reactions to changes in marital status.
Lucas Richard E.; Clark Andrew E.; Georgellis Yannis; Diener Ed 《Canadian Metallurgical Quarterly》2003,84(3):527
According to adaptation theory, individuals react to events but quickly adapt back to baseline levels of subjective well-being. To test this idea, the authors used data from a 15-year longitudinal study of over 24,000 individuals to examine the effects of marital transitions on life satisfaction. On average, individuals reacted to events and then adapted back toward baseline levels. However, there were substantial individual differences in this tendency. Individuals who initially reacted strongly were still far from baseline years later, and many people exhibited trajectories that were in the opposite direction to that predicted by adaptation theory. Thus, marital transitions can be associated with long-lasting changes in satisfaction, but these changes can be overlooked when only average trends are examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
The conflict in Northern Ireland is at its most basic a struggle between those who wish to see Northern Ireland remain part of the United Kingdom and those who wish to see the reunification of the island of Ireland. It is underpinned by historical, religious, political, economic, and psychological elements. These elements underlie the violence that has spanned the past 25 years and that has led to death and injury, led to increased community divisions, and impacted on the population's mental health. In an attempt to transform the conflict, various policy initiatives have been pursued, including attempts to reduce inequality and to improve community relations, in particular through educational initiatives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
Psychopathy in instrumental and reactive violent offenders. 总被引:1,自引:0,他引:1
Cornell Dewey G.; Warren Janet; Hawk Gary; Stafford Ed; Oram Guy; Pine Denise 《Canadian Metallurgical Quarterly》1996,64(4):783
Can violent offenders who commit acts of instrumental aggression for goal-oriented purposes such as robbery be distinguished from those who commit acts of reactive (or hostile) aggression in response to provocation? Because violent offenders often have a history of both instrumental and reactive aggression, this study distinguished between offenders with a history of at least 1 instrumental violent offense and offenders with a history of reactive violent offenses. Two studies tested the hypothesis that instrumental offenders would score higher than reactive offenders and nonviolent offenders on R. D. Hare's (1991) Psychopathy Checklist. The first study sample consisted of 106 violent and nonviolent offenders recruited from a medium-security correctional facility. The second study sample consisted of 50 violent offenders referred for pretrial forensic evaluation. In both samples, instrumental offenders could be reliably distinguished from reactive offenders on the basis of violent crime behavior and level of psychopathy. Group differences could not be attributed to participant age, race, length of incarceration, or extent of prior criminal record. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
139.
Personal ideology is an individual's philosophy of how life should be lived and of what forces influence human living. In this study S. S. Tomkins's (1963, 1965, 1978, 1987) polarity theory of ideology was used to examine the manifestation of personal ideology in 4 value-laden domains of personality. Tomkins's theoretical postulates concerning the emotional foundation of personal ideology also were tested. Analyses revealed that the 2 defining dimensions of polarity theory—humanism and normativism—are related in the predicted meaningful ways to value systems, assumptions concerning human nature, religiosity, and political orientation. Evidence also was found for Tomkins's contention that specific affect clusters serve as the foundation of personal ideology. Participants who scored high in humanism ideology related autobiographical memories containing the emotion cluster of joy, distress, fear, and shame, whereas the memories of participants with normative ideologies contained relatively more anger. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
140.
Neil C. Hyatt M. O. Jones I. Gameson M. Slaski G. B. Peacock J. A. Hriljac Peter P. Edwards 《Journal of Superconductivity and Novel Magnetism》1998,11(1):141-142
We report preliminary results concerning the synthesis and structural characterisation of the chromium stabilised 1201 phases: Hg1?xCrxSr2CuO4+δ. A systematic study of the formation of phases in this system has been undertaken, together with a combined powder neutron and synchrotron x-ray diffraction study, to address the issue of chromium clustering and ordering in this system. 相似文献