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11.
International Journal for the Advancement of Counselling - The aim of the study is to examine the mediating role of self-efficacy in the relationship between vicarious trauma (VT) and psychological...  相似文献   
12.
This study investigated the associations between cultural diversity approaches endorsed by teachers and adolescents' positive and negative intergroup contact in schools. Participants were 984 adolescents (Mage = 14.66; 62.7% female; 24.8% ethnic minority) involved in a three-wave longitudinal study between 2019 and 2020. Results highlighted that perceived equal treatment by teachers was related to higher positive and lower negative contact over time. However, perceived support for contact and cooperation and interest of teachers in children's cultural background were not related to either positive or negative contact over time. Importantly, the results were replicated across ethnic minority and majority adolescents. This study provides novel insights into the key role that teachers can play in promoting cultural diversity approaches to facilitate harmonious intergroup interactions in schools.  相似文献   
13.
This paper presents a stochastic multi-parameters divergence method for online parameter optimization of fractional-order proportional–integral–derivative (PID) controllers. The method is used for auto-tuning without the need for exact mathematical plant model and it is applicable to diverse plant transfer functions. The proposed controller tuning algorithm is capable of adaptively responding to parameter fluctuations and model uncertainties in real systems. Adaptation skill enhances controller performance for real-time applications. Simulations and experimental observations are carried on a prototype helicopter model to confirm the performance improvements obtained by the online auto-tuning of fractional-order PID structure in laboratory conditions.  相似文献   
14.
The initial time difference practical stability in terms of two measures has been investigated for nonlinear fractional differential equations in Caputo's sense and these properties have been unified with Lyapunov-like functions to establish a comparison result.  相似文献   
15.
In this special issue of Biomicrofluidics, a wide variety of applications of microfluidics to tissue engineering and cell biology are presented. The articles illustrate the benefits of using microfluidics for controlling the cellular environment in a precise yet high rate manner using minimum reagents. The topic is very timely and takes a stab at portraying a glimpse of what is to come in this exciting and emerging field of research.  相似文献   
16.
Education and Information Technologies - The technological developments of the twenty-first century have enabled the emergence of alternative teaching-learning models and instructional tools. One...  相似文献   
17.
The purpose of this study was to explore 15 graduate research assistants’ understanding of the nature of science. Data were collected through administration of a modified version of the Views of Nature of Science Questionnaire (VNOS-C). The findings suggest that graduate research assistants held underdeveloped views related to several nature of science (NOS) aspects including the argumentative nature of science, the process of modeling in science, scientists’ treatment of unexpected results, collaborative nature of science, and the process of theory formation. The discussion focuses on the missing link in preparation of future scientists and offers suggestions to address the learning needs of graduate research assistants regarding their understanding of NOS.  相似文献   
18.

Introduction

The collected and shipped blood samples are exposed to a various extra-analytical factors prior to analysis. The aim of the study was to determine the stability of analytes in serum gel tubes and plain tubes exposed to a range of storage temperatures and times after centrifugation.

Materials and methods:

Fifteen healthy volunteers were recruited and venous blood was collected into four tubes, two with and two without gel separator. Analyzing the baseline samples in 30 min, all were stored at 4ºC or 24ºC for 6, 12, 18, 24, 30, 36, 48 and 72 hours and 1 week. Sixteen biochemical anaytes were measured on each sample. Variations remained under the desirable bias considered as clinically insignificant.

Results:

On day three, most analytes remained stable including albumin, protein, creatinine, cholesterol, triglycerides, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LD) regardless of tube types. Glucose concentration decreased markedly (P = 0.001) beginning from the first hours of storage in plain serum. The stability maximized for the analytes including glucose, total bilirubin, urea nitrogen (BUN), uric acid stored at 4 ºC in gel tubes. Aspartate aminotransferase (AST) activity increased significantly (P = 0.002) up to 48-h, however bias was not significant clinically. High density lipoprotein (HDL) concentration was stable in gel tubes at 24 ºC, in plain tubes at 4 ºC stored up to 36-h.

Conclusion:

Serum gel or non-gel tubes might be used interchangeably for 11 analytes chilled or at 24 ºC, whereas some restrictions must be applied for glucose, AST, BUN, HDL, and uric acid.  相似文献   
19.
This study investigated the effects of a multi-pronged approach of increasing the nature of science (NOS) understandings of high school science students. The participants consist of 63 high school students: 31 in the intervention group and 32 in the control group. Explicit/reflective NOS instruction was imbedded within authentic inquiry experiences and supported by online discussions. The students in the intervention group were prompted to engage in various discussions focusing on essential tenets of NOS in an online environment that assured student confidentiality. NOS views were assessed through multiple data sources including pre- and post-intervention questionnaires as well as students’ responses to online discussion prompts. Results show that the instructional intervention used in this study which combined explicit/reflective NOS instruction with intense inquiry exposure along with ample reflective opportunities in an anonymous online discussion format led to positive learning gains in participants’ understanding the NOS aspects assessed. Implications for enhancing data collection with high school students and for promising professional development opportunities for science educators are discussed.  相似文献   
20.
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