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131.
132.
The present study was undertaken to evaluate antidiabetic and antioxidant activities of Cayratia trifolia root extract against streptozotocin induced diabetes in experimental rats to scientifically validate its use against diabetes in some parts of India. Ethanolic extract, showing the highest activity in in vitro experiments, was prepared in saline and administered orally to streptozotocin induced albino Wistar diabetic rats for 21 days. Biochemical parameters liver and muscles glycogen and in vivo antioxidant activity in normal, diabetic control, standard (metformin) and treated animals were determined and compared. Attempt was made to isolate, purify and characterize one of the major secondary metabolites in extract by range of chromatographic and spectroscopic techniques. Treatment of streptozotocin induced diabetic rats with ethanolic root extract (500 mg/kg) caused significant (P < 0.01) reduction in blood glucose (312–178 mg/dL), increase in body weight (181–219 g) and serum insulin (1.28–2.26 IU/dL). It also maintained lipid profile and tests of liver and kidney functions within normal range as compared to diabetic control rats and almost at par with standard drug metformin. The oxidative stress induced decline in glutathione and catalase in liver and kidney tissues showed recovery nearly to normal level as a function of treatment. The GC–MS profile of the extract showed relatively high concentration of β-sitosterol which was characterized by different spectroscopic and chromatographic techniques. The result scientifically and comprehensively validate the reported use of roots of this indigenous plant against diabetes. A strong antioxidant activity of the ethanolic root extract suitably compliments the antidiabetic effect.  相似文献   
133.
Learning analytics is a fast-growing discipline. Institutions and countries alike are racing to harness the power of using data to support students, teachers and stakeholders. Research in the field has proven that predicting and supporting underachieving students is worthwhile. Nonetheless, challenges remain unresolved, for example, lack of generalizability, portability and failure to advance our understanding of students' behaviour. Recently, interest has grown in modelling individual or within-person behaviour, that is, understanding the person-specific changes. This study applies a novel method that combines within-person with between-person variance to better understand how changes unfolding at the individual level can explain students' final grades. By modelling the within-person variance, we directly model where the process takes place, that is the student. Our study finds that combining within- and between-person variance offers a better explanatory power and a better guidance of the variables that could be targeted for intervention at the personal and group levels. Furthermore, using within-person variance opens the door for person-specific idiographic models that work on individual student data and offer students support based on their own insights.

Practitioner notes

What is already known about this topic
  • Predicting students' performance has commonly been implemented using cross-sectional data at the group level.
  • Predictive models help predict and explain student performance in individual courses but are hard to generalize.
  • Heterogeneity has been a major factor in hindering cross-course or context generalization.
What this paper adds
  • Intra-individual (within-person) variations can be modelled using repeated measures data.
  • Hybrid between–within-person models offer more explanatory and predictive power of students' performance.
  • Intra-individual variations do not mirror interindividual variations, and thus, generalization is not warranted.
  • Regularity is a robust predictor of student performance at both the individual and the group levels.
Implications for practice
  • The study offers a method for teachers to better understand and predict students' performance.
  • The study offers a method of identifying what works on a group or personal level.
  • Intervention at the personal level can be more effective when using within-person predictors and at the group level when using between-person predictors.
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