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101.
Recent acquisitions on the early detection and monitoring of the progression of diabetic complications (nephropathy) using the techniques of enzymology (lysosomal enzymes) are reviewed. it appears that the kidney is the principal source of urinary lysosomal enzymes. Urinary samples for lysosomal enzyme determination can be either 24-hour or spot-collection. The use of synthetic substrates (4-methylumbelliferyl substrates) provides an easy, inexpensive, sensitive and highly reproducible method of lysosomal enzyme assay. It is recommended that more than one enzyme be assayed in the process. The use of fractional enzyme excretion (FEE) ratios is further recommended. The urinary lysosomal glycosidases investigated and found to be of particular diagnostic value in the early detection of diabetic nephropathy include N-acetyl-β-D-glucosaminidase (β-hexosaminidase, NAG), β-glucuronidase and β-galactosidase, with NAG being the most useful indicator. Urinary NAG can be used in monitoring the progression of diabetic nephropathy. The fluorimetric assay of lysosomal glycosidases is particuarly recommended in developing countries since it is simple, sensitive and inexpensive.  相似文献   
102.
Although inhibitory control is typically associated with positive outcomes, several theoretical frameworks suggest that too little and too much inhibitory control may be problematic. Using a longitudinal, latent variable approach, we examined whether a multi-method index of inhibitory control at Time 1 (N = 105, 52 girls, Mage = 3.50 years, 87% White) predicted observed social behavior with an unfamiliar peer and maternal report of preschoolers’ mental health difficulties at Time 2 (Mage = 4.76 years). Data collection occurred between 2017 and 2019. Inhibitory control displayed a U-shaped relation with prospective outcomes, where high and low levels of inhibitory control were associated with higher levels of avoidant social behaviors and mental health difficulties. The results are discussed in the context of under- and over-regulation in understanding individual differences in children's social behavior and mental health difficulties.  相似文献   
103.
E‐learning tools and technologies have been used to supplement conventional courses in higher education institutions creating a “hybrid” e‐learning module that aims to enhance the learning experiences of students. Few studies have addressed the acceptance of hybrid e‐learning by learners and the factors affecting the learners’ satisfaction with these tools. This study assesses hybrid e‐learning acceptance by learners using three critical success factors: instructor characteristics, information technology infrastructure, and organizational and technical support. Structural equation modeling was applied to examine and validate the hypothesized relationships among the three factors and their effects on learners’ acceptance of hybrid e‐learning. A total of 538 usable responses from university students were used to validate the proposed research model. The influence of the three factors on learners’ decision to accept hybrid e‐learning was empirically examined. The results show that all three factors significantly and directly impacted the learners’ acceptance of hybrid e‐learning courses. Information technology infrastructure and organizational support were proven to be key determinants of the instructor characteristics as a critical success factor of hybrid e‐learning acceptance by learners. Implications of this work for higher education institutions, researchers, and instructors are described.  相似文献   
104.
105.
Carboplatin is a chemotherapeutic agent used against various malignancies such as ovarian carcinoma. The aim of this study is to improve the therapeutic efficacy of carboplatin using pegylated liposomal nanocarriers. Nanoparticles were synthesized using thin film hydration technique and characterized for shape morphology, particle size, zeta potential and drug-release properties. In the next step, A2780S and A2780CP ovarian cancer cell lines were used to determine the efficacy of nanodrug by MTT assay. The particle size and zeta potential of nanodrug were measured 244.3 ± 19.6 nm and ?22.9 ± 1.7 mV, respectively. High encapsulation capacity (78.6 ± 3.7 %) confirmed the efficiency of technique. The cytotoxicity results also showed that nanodrug compared to free drug improve the efficacy of carboplatin against both A2780S (P < 0.01) and A2780CP (P < 0.05) cell lines. In conclusion, the findings of our study suggested pegylated liposomal nanocarriers are proper for carboplatin delivery to ovarian cancer cell lines A2780S and A2780CP.  相似文献   
106.
The dysregulation of social fear has been widely studied in children's shyness, but we know little about how shy children regulate during unfair treatment. We first characterized developmental patterns of children's shyness (N = 304, ngirls = 153; 74% White, 26% Other) across 2 (Mage = 2.07), 3 (Mage = 3.08), 4 (Mage = 4.08), and 6 (Mage = 6.58) years of age. Data collection occurred from 2007 to 2014. At age 6, the high stable group had higher cardiac vagal withdrawal and lower expressed sadness and approach-related regulatory strategy than the low stable group when being treated unfairly. Although shy children may be more physiologically impacted by being treated unfairly, they may mask their sadness to signal appeasement.  相似文献   
107.
Traditional item analyses such as classical test theory (CTT) use exam-taker responses to assessment items to approximate their difficulty and discrimination. The increased adoption by educational institutions of electronic assessment platforms (EAPs) provides new avenues for assessment analytics by capturing detailed logs of an exam-taker's journey through their exam. This paper explores how logs created by EAPs can be employed alongside exam-taker responses and CTT to gain deeper insights into exam items. In particular, we propose an approach for deriving features from exam logs for approximating item difficulty and discrimination based on exam-taker behaviour during an exam. Items for which difficulty and discrimination differ significantly between CTT analysis and our approach are flagged through outlier detection for independent academic review. We demonstrate our approach by analysing de-identified exam logs and responses to assessment items of 463 medical students enrolled in a first-year biomedical sciences course. The analysis shows that the number of times an exam-taker visits an item before selecting a final response is a strong indicator of an item's difficulty and discrimination. Scrutiny by the course instructor of the seven items identified as outliers suggests our log-based analysis can provide insights beyond what is captured by traditional item analyses.

Practitioner notes

What is already known about this topic
  • Traditional item analysis is based on exam-taker responses to the items using mathematical and statistical models from classical test theory (CTT). The difficulty and discrimination indices thus calculated can be used to determine the effectiveness of each item and consequently the reliability of the entire exam.
What this paper adds
  • Data extracted from exam logs can be used to identify exam-taker behaviours which complement classical test theory in approximating the difficulty and discrimination of an item and identifying items that may require instructor review.
Implications for practice and/or policy
  • Identifying the behaviours of successful exam-takers may allow us to develop effective exam-taking strategies and personal recommendations for students.
  • Analysing exam logs may also provide an additional tool for identifying struggling students and items in need of revision.
  相似文献   
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