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1.
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   
2.

Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests  相似文献   
3.
This article is a response to Pike and Dunne’s research. The focus of their analysis is on reflections of studying science post-16. Pike and Dunne draw attention to under enrollments in science, technology, engineering, and mathematics (STEM) fields, in particular, in the field of physics, chemistry and biology in the United Kingdom. We provide an analysis of how the authors conceptualize the problem of scientific career choices, the theoretical framework through which they study the problem, and the methodology they use to collect and analyze data. In addition, we examine the perspective they provide in light of new developments in the field of students’ attitudes towards science and mathematics. More precisely, we draw attention to and explicate the authors’ use of identity from the perspective of emerging theories that explore the relationships between the learner and culture in the context of science and mathematics.  相似文献   
4.
This study investigates the development of an instrument to explore the views of student teachers in Turkey towards using Facebook as a tool for teaching and learning. A five-point Likert-type scale was developed for a sample of 687 student teachers from various fields in Adiyaman, Mustafa Kemal, and Inonu Universities. The sample included 445 participants in the first application and 242 participants in the second. A literature review, students’ comments, and relevant Facebook research results were considered in order to establish the items for the scale. A comparative analysis of previous studies and instruments yielded an original 33-item pool, and experts’ judgments were consulted to confirm the content validity of the scale. Exploratory and confirmatory factor analyses were conducted to determine the factor structure of the scale, revealing 17 items that could be grouped under three general factors. A Cronbach’s coefficient (α) was employed to determine the internal consistency coefficients for the whole scale and its subscales. Results indicate that this learning scale (FLTS) is a valid and reliable instrument to investigate the use of Facebook as a learning tool.  相似文献   
5.
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   
6.
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   
7.
IntroductionBlood gas analysis (BGA) is an essential test used for years to provide vital information in critically ill patients. However, the instability of the blood gases is a problem. We aimed to evaluate time and temperature effects on blood gas stability.Materials and methodsArterial blood was collected from 20 patients into syringes. Following BGA for baseline, syringes were divided into groups to stand at 4°C and 22°C for 30, 60, 90, 120 minutes. All were tested for pH, partial pressure of carbon dioxide (pCO2), partial pressure of oxygen (pO2), oxygen saturation (sO2), oxyhemoglobin (O2Hb), sodium, potassium, glucose, lactate, oxygen tension at 50% hemoglobin saturation (p50), and bicarbonate. A subgroup analysis was performed to detect the effect of air on results during storage. Percentage deviations were calculated and compared against the preset quality specifications for allowable total error.ResultsAt 4°C, pO2 was the least stable parameter. At 22°C, pO2 remained stable for 120 min, pH and glucose for 90 min, lactate and pCO2 for 60 min. Glucose and lactate were stable when chilled. Air bubbles interfered pO2 regardless of temperatures, whereas pCO2 increased significantly at 22°C after 30 min, and pH decreased after 90 min. Bicarbonate, sO2, O2Hb, sodium, and potassium were the unaffected parameters.ConclusionsCorrect BGA results are essential, and arterial sample is precious. Therefore, if immediate analysis cannot be performed, up to one hour, syringes stored at room temperature will give reliable results when care is taken to minimize air within the blood gas specimen.  相似文献   
8.

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   
9.
Journal of Science Education and Technology - Today, science educators accept that digital literacy has been one of the key concepts for science teachers in terms of creating meaningful science...  相似文献   
10.
The present article scrutinizes “the unique American vision of childhood” (UAVC) as a phenomenon undermining high academic expectations and good work ethics, and in turn, contributing to the generally low academic achievement of U.S. students compared to their counterparts in other advanced countries. It starts with a definition of UAVC, followed by a discussion of how influential it has been. The article goes on to state three reasons why UAVC is troublesome and misleading, especially in an era of global competition. Excuses devised by the proponents for UAVC’s adverse effects are also revealed. The article ends with recommendations for future research and a conclusion elaborating on the consequences of UAVC and the likelihood that other countries might adopt a similar mentality.  相似文献   
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