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61.
Zubieta-Calleja G Zubieta-Castillo G Zubieta-Calleja L Ardaya-Zubieta G Paulev PE 《Indian journal of clinical biochemistry : IJCB》2011,26(1):62-65
As the oxygen tension of inspired air falls with increasing altitude in normal subjects, hyperventilation ensues. This acute
respiratory alkalosis, induces increased renal excretion of bicarbonate, returning the pH back to normal, giving rise to compensated
respiratory alkalosis or chronic hypocapnia. It seems a contradiction that so many normal people at high altitude should permanently
live as chronic acid–base patients. Blood gas analyses of 1,865 subjects at 3,510 m, reported a P
aCO2 (arterial carbon dioxide tension ± SEM) = 29.4 ± 0.16 mmHg and pH = 7.40 ± 0.005. Base excess, calculated with the Van Slyke
sea level equation, is −5 mM (milliMolar or mmol/l) as an average, suggesting chronic hypocapnia. THID, a new term replacing
“Base Excess” is determined by titration to a pH of 7.40 at a P
aCO2 of 5.33 kPa (40 mmHg) at sea level, oxygen saturated and at 37°C blood temperature. Since our new modified Van Slyke equations
operate with normal values for P
aCO2 at the actual altitude, a calculation of THID will always result in normal values—that is, zero. 相似文献
62.
Javier A. Gallegos Norelys Aguila-Camacho Manuel A. Duarte-Mermoud Juan C. Travieso-Torres Gustavo E. Ceballos-Benavides 《Journal of The Franklin Institute》2021,358(7):3943-3963
This paper deals with systems that can switch their structure, including the differentiation order. It is shown that there are several non-equivalent cases for them, which all coincide when the derivation order is not switched but fixed at 1. For each of these cases, (asymptotic) stability results are obtained in this paper. This is accomplished by generalizing Common Lyapunov Functions (CLF) and Multiple Lyapunov Functions (MLF) methods, the latter when applied to fractional switching systems (FSS) in the resetting. Several examples are presented to illustrate that such Lyapunov functions exist for linear and nonlinear switched order systems. It is shown that the resetting fractional switching can be easily implemented by standard software. Finally, applications in adaptive integer-order problems are made by exploiting features of both fractional and integer-order systems. 相似文献
63.
Social media technologies have begun to enter the governmental workplace as tools to accomplish improved public service and engagement. Widespread recognition of the potential of social media technology for achieving public outcomes does not match our understanding about how and why specific tools are being used for specific purposes. This paper makes use of newly collected national survey data from local government managers in five different agencies to address the questions: which social media tools are being used, for which tasks or purposes; and what organizational characteristics influence the coupling of task and technology. Findings reveal patterns of social media tool application for particular purposes, although organizations do not all use social media tools in the same way. Moreover, regression analysis shows that different organizational factors – work characteristics, innovativeness, technology and management capacity and stakeholder influence – predict each of the four technology–task couplings — social media for dissemination, social media for feedback on service quality, social media for participation, and social media for internal work collaboration. This study demonstrates that social media tools are not a monolithic group and calls for greater research attention to the complex interactions among social media technology, task and organizational context. 相似文献
64.
65.
Díaz MP Rizo OD Díaz AL Aparicio EE Díaz RR 《Journal of Zhejiang University. Science. B》2006,7(12):947-956
A discriminant method for optimizing activity in nuclear medicine studies is validated by comparison with ROC (received operating characteristic)-curves. The method is tested in 21 single photon emission computerized tomography (SPECT), performed with a cardiac phantom. Three different lesions (Lb L2 and L3) were placed in the myocardium-wall by pairs fbr each SPECT. Three activities (84, 37 or 18.5 MBq) of 99mTc were used as background. Linear discriminant analysis was used to select the parameters that characterize image quality among the measured variables in the images [(Background-to-Lesion (B/Li) and Signal-to-Noise (S/N) ratios)]. Two clusters with different image quality (P=0.021 ) were obtained. The ratios B/Lj, B/L2 and B/L3 are the parameters used to construct the function with 100% of cases correctly classified into the clusters. The value of 37 MBq was the lowest tested activity for which good results for the B/Li ratios were obtained. The result coincides with the applied ROC-analysis (r=0.89). 相似文献
66.
The Longitudinal Associations Among Temperament,Parenting, and Turkish Children's Prosocial Behaviors 下载免费PDF全文
Deborah J. Laible Asiye Kumru Gustavo Carlo Cara Streit Bilge Selcuk Melike Sayil 《Child development》2017,88(4):1057-1062
In Turkey, responsive behaviors toward kin are expected from children. Despite this, we know little about the factors that influence young Turkish children's prosocial behaviors. The goal was to explore how temperament and parenting are related to children's prosocial development in Turkey. A total of 293 Turkish children (Mage = 49 months; 48.12% females) were followed up for 3 years. Mothers completed measures of their child's prosocial behaviors, as well as measures of their warmth, inductive reasoning, and the child's approach and reactivity. Maternal warmth predicted children's reactivity, and maternal induction predicted children's sociability. Children's reactivity was inversely related to children's helping behavior and sociability was related to more prosocial behavior. Maternal warmth had indirect links with helping through lessening children's reactivity. 相似文献
67.
The aim of this research has been to prove the efficacy of an intervention programme on the problems of phonetic and semantic fluency and mazes in narrative discourse in children with Specific Language Impairment (SLI). The sample consisted of 34 children diagnosed with SLI and 34 children with normal language development. For the selection of the sample, the Clinical Evaluation of Language Fundamentals (CELF-3), Peabody Picture Vocabulary Test, Hearing Association and the Visual Association subtests of the Illinois Test of Psycholinguistic Abilities (ITPA), and the Kaufman Brief Intelligence Test (KBIT) were used. Performance in phonemes (F, A & S), semantic fluency (animals) and the appearance of mazes or repairs in a narrative task were also evaluated. The intervention programme consisted of 72 sessions of 15 minutes each, using phonetic and semantic fluency activities with phonetic and semantic clues. Differences between groups were statistically significant in repetitions and false connectors. 相似文献
68.
Luiz Gustavo Marin Emed Daniela Gunther Passaglia Surya T. Guerios Paula G. D. João André I. S. Moser Dulcinéia S. P. Abdalla 《Journal of sports sciences》2016,34(17):1657-1661
We aimed to evaluate the effects of a 24-h ultramarathon, an aerobic test of high physical load, on lipid profile and apolipoproteins B (ApoB) and A1 (ApoA1) levels, minimally modified low-density lipoprotein (LDL), and oxidised LDL. Prospective evaluation of 16 male athletes who participated in an ultramarathon run, where the objective was to run the greatest distance possible in 24 h. Fourteen participants completed the run. The mean distance achieved was 133.1 km (maximum of 169.6 km). There was a trend in reduction of triglycerides and total cholesterol (P = 0.06 and 0.05, respectively), without significant modifications in high-density lipoprotein, LDL and ApoA1 levels (P = 0.16; 0.55 and 0.67). There was a marked reduction in ApoB levels (P < 0.001), correlated directly to the distance covered (Pearson R = 0.68). Accordingly, an increase in the LDL/ApoB ratio was observed. The stress of this physical activity was not associated to an increase in minimally modified LDL or oxidised LDL. Lipid profile levels were not acutely altered by prolonged physical activity. Similarly, there was no evidence of greater oxidation of LDL over a 24-h period of physical activity. The reduction in ApoB was directly proportional to the distance covered, suggesting an acute positive change in phenotype of LDL molecules. 相似文献
69.
ABSTRACTThe study examined the links among maternal warmth and adolescents’ empathic concern, moral conviction and prosocial behaviors. Participants were 311 adolescents from a low-income community (M age = 16.10 years; range = 14–19 years; 58.7% girls; 82.7% white; 13.6% Latinx). The results demonstrated that maternal warmth was positively associated with adolescents’ empathic concern and moral conviction. Empathic concern was positively associated with three common forms of prosocial behaviors, and moral conviction was positively associated with four types of prosocial behaviors. Empathic concern and moral conviction also interacted to predict selfishly and selflessly motivated prosocial behaviors. Discussion will focus on the role of maternal warmth in fostering sociomoral tendencies. 相似文献
70.
Beatriz Mazas Mª Rosario Fernández Manzanal Francisco Javier Zarza Gustavo Adolfo María 《International Journal of Science Education》2013,35(11):1775-1799
This work presents the development of a scale of attitudes of secondary-school and university students towards animal welfare. A questionnaire was drawn up following a Likert-type scale attitude assessment model. Four components or factors, which globally measure animal welfare, are proposed to define the object of the attitude. The components are animal abuse for pleasure or due to ignorance (C1), leisure with animals (C2), farm animals (C3) and animal abandonment (C4). The final version of the questionnaire contains 29 items that are evenly distributed among the four components indicated, guaranteeing that each component is one-dimensional. A sample of 329 students was used to validate the scale. These students were aged between 11 and 25, and were from secondary schools in Aragon and the University in Zaragoza (Aragon's main and largest city, located in NE Spain). The scale shows good internal reliability, with a Cronbach's alpha value of 0.74. The questionnaire was later given to 1,007 students of similar levels and ages to the sample used in the validation, the results of which are presented in this study. The most relevant results show significant differences in gender and level of education in some of the components of the scale, observing that women and university students rate animal welfare more highly. 相似文献