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91.
Haidar A Potocka E Boulet B Umpleby AM Hovorka R 《Computer methods and programs in biomedicine》2012,108(1):102-112
A new stochastic computational method was developed to estimate the endogenous glucose production, the meal-related glucose appearance rate (R(a meal)), and the glucose disposal (R(d)) during the meal tolerance test. A prior probability distribution was adopted which assumes smooth glucose fluxes with individualized smoothness level within the context of a Bayes hierarchical model. The new method was contrasted with the maximum likelihood method using data collected in 18 subjects with type 2 diabetes who ingested a mixed meal containing [U-(13)C]glucose. Primed [6,6-(2)H(2)]glucose was infused in a manner that mimicked the expected endogenous glucose production. The mean endogenous glucose production, R(a meal), and R(d) calculated by the new method and maximum likelihood method were nearly identical. However, the maximum likelihood gave constant, nonphysiological postprandial endogenous glucose production in two subjects whilst the new method gave plausible estimates of endogenous glucose production in all subjects. Additionally, the two methods were compared using a simulated triple-tracer experiment in 12 virtual subjects. The accuracy of the estimates of the endogenous glucose production and R(a meal) profiles was similar [root mean square error (RMSE) 1.0±0.3 vs. 1.4±0.7μmol/kg/min for EGP and 2.6±1.0 vs. 2.9±0.9μmol/kg/min for R(a meal); new method vs. maximum likelihood method; P=NS, paired t-test]. The accuracy of R(d) estimates was significantly increased by the new method (RMSE 5.3±1.9 vs. 4.2±1.3; new method vs. ML method; P<0.01, paired t-test). We conclude that the new method increases plausibility of the endogenous glucose production and improves accuracy of glucose disposal compared to the maximum likelihood method. 相似文献
92.
Omar K. Hussain Tharam Dillon Farookh Khadeer Hussain Elizabeth Chang 《Journal of Intelligent Manufacturing》2012,23(6):2069-2084
In Demand-driven Production with Just-in-Time inputs, there are several sources of uncertainty which impact on the manufacturer??s ability to meet the required customer??s demand within the given time frame. This can result in a loss of revenue and customers, which will have undesirable impacts on the financial aspects and on the viability of the manufacturer. Hence, a key concern for manufacturers in just-in-time production is to determine whether they can meet a specific level of demand within a given time frame, to meet the customers?? orders and also to achieve the required revenue target for that period of time. In this paper, we propose a methodology by which a manufacturer can ascertain the probability of not meeting the required demand within a given period by considering the uncertainties in the availability of production units and raw materials, and the loss of financial revenue that it would experience as a result. 相似文献
93.
Generation is thought to enhance both item-specific and relational processing of generated targets as compared with read words (M. A. McDaniel & P. J. Waddill, 1990). Generation facilitates encoding of the cue-target relation and sometimes boosts encoding of relations across list items. Of interest is whether generation can also increase the encoding of target-location associations. Because the literature on this point is mixed, 3 procedural differences between 2 studies (E. J. Marsh, G. Edelman, & G. H. Bower, 2001; N. W. Mulligan, 2004) were identified and manipulated. A positive generation effect was found for location memory, but this effect was reduced when subjects wrote down the study words and when the filler task involved generation. Generation can enhance location memory in addition to item memory but only if the experimental parameters do not interfere with the processing benefits of generation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Muraven Mark; Collins R. Lorraine; Morsheimer Elizabeth T.; Shiffman Saul; Paty Jean A. 《Canadian Metallurgical Quarterly》2005,19(3):253
The authors examined whether the reciprocal relationship between alcohol consumption and distress unfolded over time in 2 samples of social drinkers. Participants monitored their alcohol intake and their cognitive and emotional responses to that drinking on hand-held computers. On mornings after drinking, those who had violated their self-imposed limits the day before reported more guilt, even after controlling for acute negative symptoms of drinking and amount consumed. Reciprocally, guilt led to poorer self-regulation of alcohol intake: Greater distress over alcohol consumption was linked to more intake, intoxication, and more limit violations. Individual differences moderated the relationships among limit violations, distress, and drinking. Consistent with the limit violation effect, violating a limit produced distress over consumption among social drinkers, and they responded to that distress by drinking more. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Frey Karin S.; Hirschstein Miriam K.; Snell Jennie L.; Edstrom Leihua Van Schoiack; MacKenzie Elizabeth P.; Broderick Carole J. 《Canadian Metallurgical Quarterly》2005,41(3):479
Six schools were randomly assigned to a multilevel bullying intervention or a control condition. Children in Grades 3-6 (N=1,023) completed pre- and posttest surveys of behaviors and beliefs and were rated by teachers. Observers coded playground behavior of a random subsample (n=544). Hierarchical analyses of changes in playground behavior revealed declines in bullying and argumentative behavior among intervention-group children relative to control-group children, increases in agreeable interactions, and a trend toward reduced destructive bystander behavior. Those in the intervention group reported enhanced bystander responsibility, greater perceived adult responsiveness, and less acceptance of bullying/aggression than those in the control group. Self-reported aggression did not differ between the groups. Implications for future research on the development and prevention of bullying are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Weaver Kathryn E.; Llabre María M.; Durán Ron E.; Antoni Michael H.; Ironson Gail; Penedo Frank J.; Schneiderman Neil 《Canadian Metallurgical Quarterly》2005,24(4):385
The authors tested a structural model that incorporated age, time since diagnosis, social support, coping, and negative mood as predictors of medication adherence and HIV viral load on 188 men and 134 women on highly active antiretroviral therapy (HAART). The authors used psychosocial latent factors formed from baseline measures to predict latent factors of adherence, as assessed by electronic monitoring and self-report, and viral load defined by indicators assessed over a 15-month period. Results from the model indicate that greater negative mood and lower social support are related to greater use of avoidance-oriented coping strategies. Use of these coping strategies by patients on HAART is related to poorer medication adherence and, subsequently, higher viral load. This model advances researchers' understanding of the contribution of psychosocial variables in predicting treatment adherence and disease progression in HIV-positive men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Thin films of Bi2Se3, Bi2Se2.9Te0.1, Bi2Se2.7Te0.3 and Bi2Se2.6Te0.4 are prepared by compound evaporation. Micro structural, optical and electrical measurements are carried out on these films. X-ray diffraction pattern indicates that the as-prepared films are polycrystalline in nature with exact matching of standard pattern. The composition and morphology are determined using energy dispersive X-ray analysis and scanning electron microscopy (SEM). The optical band gap, which is direct allowed, is 0.67 eV for Bi2Se3 thin films and the activation energy is 53 meV. Tellurium doped thin films also show strong optical absorption corresponding to a band gap of 0.70-0.78 eV. Absolute value of electrical conductivity in the case of tellurium doped thin film shows a decreasing trend with respect to parent structure. 相似文献
98.
The surveillance of a manoeuvring target with multiple sensors in a coordinated manner requires a method for selecting and positioning groups of sensors in real time. Herein, the principles of dispatching, as used for the effective operation of service vehicles, are considered. The object trajectory is first discretized into a number of demand instants (data acquisition times), to which groups of sensors are assigned, respectively. Heuristic rules are used to determine the composition of each sensor group by evaluating the potential contribution of each sensor. In the case of dynamic sensors, the position of each sensor with respect to the target is also specified. Our proposed approach aims to improve the quality of the surveillance data in three ways: (1) The assigned sensors are manoeuvred into “optimal” sensing positions, (2) the uncertainty of the measured data is mitigated through sensor fusion, and (3) the poses of the unassigned sensors are adjusted to ensure that the surveillance system can react to future object manoeuvres. If a priori target trajectory information is available, the system performance may be further improved by optimizing the initial pose of each sensor off-line. The advantages of dispatching dynamic sensors over similar static-sensor systems are demonstrated through comprehensive simulations. 相似文献
99.
Kubany Edward S.; Hill Elizabeth E.; Owens Julie A.; Iannce-Spencer Cindy; McCaig Mari A.; Tremayne Ken J.; Williams Paulette L. 《Canadian Metallurgical Quarterly》2004,72(1):3
This article describes a second treatment-outcome study of cognitive trauma therapy for battered women with posttraumatic stress disorder (PTSD; CTT-BW). CTT-BW includes trauma history exploration: PTSD education; stress management; exposure to abuse and abuser reminders; self-monitoring of negative self-talk; cognitive therapy for guilt; and modules on self-advocacy, assertiveness, and how to identify perpetrators. One hundred twenty-five ethnically diverse women were randomly assigned to immediate or delayed CTT-BW. PTSD remitted in 87% of women who completed CTT-BW, with large reductions in depression and guilt and substantial increases in self-esteem. White and ethnic minority women benefited equally from CTT-BW. Similar treatment outcomes were obtained by male and female therapists and by therapists with different levels of education and training. Gains were maintained at 3- and 6-month follow-ups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Dix Theodore; Gershoff Elizabeth T.; Meunier Leah N.; Miller Pamela C. 《Canadian Metallurgical Quarterly》2004,40(6):1212
This study investigated the maternal concerns and emotions that may regulate one form of sensitive parenting, support for children's immediate desires or intentions. While reviewing a videotape of interactions with their 1-year-olds, mothers who varied on depressive symptoms reported concerns and emotions they had during the interaction. Emotions reflected outcomes either to children (child-oriented concerns) or to mothers themselves (parent-oriented concerns). Child-oriented concerns were associated with fewer negative emotions and more supportive behavior. Supportive parenting was high among mothers who experienced high joy and worry and low anger, sadness, and guilt. However, relations depended on whether emotions were child or parent oriented: Supportive behavior occurred more when emotions were child oriented. In addition, as depressive symptoms increased, mothers reported fewer child-oriented concerns, fewer child-oriented positive emotions, and more parent-oriented negative emotions. They also displayed less supportive behavior. Findings suggest that support for children's immediate intentions may be regulated by parents' concerns, immediate emotions, and depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献