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121.
Computer-based approaches to balancing chemical equations are discussed. Out of 13 methods surveyed, 6 are based on matrix, 2 are interactive programs, 1 is a stand alone system, 1 is developed in algorithm in Basic, 1 is based on design engineering, 1 is written in HyperCard, and 1 prepared for the World Wide Web. Features in addition to balancing chemical equations include the following: solve possible reactions from a list of molecules and ions, determine the number of independent chemical reactions, calculate yields, predict mass relationships, and balance rare reactions. Research and development issues are addressed. 相似文献
122.
Over the series of articles on circadian rhythms, we saw that living organisms exhibit daily rhythms in multiple behaviours and physiological processes. Although some rhythms may be passive responses to 24 h environmental cycles, many are regulated by endogenous-rhythmgenerating machinery called circadian clocks. We have introduced the concept of circadian clocks, their organization and the underlying molecular mechanisms. In this article, we will dwell upon one of the most fundamental questions pertaining to circadian clocks, ‘Why do we have them?’. The aim of this article is not to provide answers, but to discuss the efforts and strategies used to address this question and critically evaluate explanations proposed till date. 相似文献
123.
124.
D. Ray Reutzel Cindy D. Jones Sarah K. Clark Tamara Kumar 《The Journal of educational research》2016,109(1):81-98
There has been no research reported about if or how well primary grade teachers can identify information text structures in children's authentic informational texts. The ability to do so accurately and reliably is a prerequisite for teachers to be able to teach students how to recognize and use text structures to assist them in comprehending informational texts. The authors report the development of the Informational Text Structure Survey (ITS2). Prior to training, primary grade teachers demonstrated low accuracy and reliability in identifying traditional expository text structures in well-structured children's grade level–appropriate informational texts. Results after training with the ITS2 instrument showed significant improvements in the teachers’ accuracy and reliability in identifying traditional informational text structures in well-structured children's grade level–appropriate informational texts after training with the ITS2 instrument. 相似文献
125.
Anindya Kumar Biswas 《Resonance》2018,23(6):663-668
In this pedagogical article, we elucidate the direct derivation of total power emitted by an accelerating charged particle, known as Liénard’s generalisation, using differentiation under integral sign technique. 相似文献
126.
N. Kumar 《Resonance》2013,18(5):458-467
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. 相似文献
127.
Sujeet Kumar Sharma Mohamed Sarrab Hafedh Al-Shihi 《Interactive Learning Environments》2017,25(7):847-858
The growth of Smartphone usage, increased acceptance of electronic learning (E-learning), the availability of high reliability mobile networks and need for flexibility in learning have resulted in the growth of mobile learning (M-learning). This has led to a tremendous interest in the acceptance behaviors related to M-learning users among the information systems researchers. Despite a large amount of significant research in the field of M-learning, the measurement of user acceptance of M-learning has not received attention. This research study intends to develop and validate a survey that measures users’ acceptance of M-learning. A total sample of 806 university and higher college students from different institutes in Oman participated in this study. This research study was conducted in two stages. The first stage using a sample size of 388 students initiated a generic questionnaire, and examined factorial validity and reliability. The second stage that was conducted using different sample of 418 students employed confirmatory factor analysis to establish factorial validity and measurement invariance. A correlated six-factor model (Flexibility, Suitability, Enjoyment, Efficiency, Economic and Social) was fit using maximum likelihood estimation. The internal consistency and item reliability of Mobile Learning Acceptance Measure was found to be at acceptable level for both samples. 相似文献
128.
Ishrat Husain Ramesh Chander Jitendra Kumar Saxena Abbas Ali Mahdi Farzana Mahdi 《Indian journal of clinical biochemistry : IJCB》2015,30(1):72-77
The antidyslipidemic activity of Ocimum sanctum leaf extract was studied in streptozotocin induced diabetic rats. In this model, there was significant increase in plasma markers of diabetic-dyslipidemia following diminution of lipid metabolizing enzymes. Oral administration of leaf extract (500 mg/kg b.w.p.o.) for 15 days resulted in significant decrease in diabetogenic and dyslipidemia parameters; namely blood glucose, glycosylated hemoglobin, lipid peroxide, free fatty acids, small dense low density lipoprotein, lipid and protein components of plasma lipoproteins, adipose and liver. The regulation of lipids was accompanied by stimulation of postheparin lipolytic activity, reactivation of lecithin cholesterol acyl transferase and hepatic lipoprotein lipase enzymes. The results of the present study demonstrated antidyslipidemic and antioxidant activities in leaf extract of O. sanctum which could be used in prevention of diabetic-dyslipidemia and related complications. 相似文献
129.
Lin Tang Wei-jun Luo Zhen-li He Hanumanth Kumar Gurajala Yasir Hamid Kiran Yasmin Khan Xiao-e Yang 《Journal of Zhejiang University. Science. B》2018,19(2):147-158
Vegetables are important constituents of the human diet. Heavy metals and nitrate are among the major contaminants of vegetables. Consumption of vegetables and fruits with accumulated heavy metals and nitrate has the potential to damage different body organs leading to unwanted effects. Breeding vegetables with low heavy metal and nitrate contaminants is a cost-effective approach. We investigated 38 water spinach genotypes for low Cd and nitrate co-accumulation. Four genotypes, i.e. JXDY, GZQL, XGDB, and B888, were found to have low co-accumulation of Cd (<0.71 mg/kg dry weight) and nitrate (<3100 mg/kg fresh weight) in the edible parts when grown in soils with moderate contamination of both Cd (1.10 mg/kg) and nitrate (235.2 mg/kg). These genotypes should be appropriate with minimized risk to humans who consume them. The Cd levels in the edible parts of water spinach were positively correlated with the concentration of Pb or Zn, but Cd, Pb, or Zn was negatively correlated with P concentration. These results indicate that these three heavy metals may be absorbed into the plant in similar proportions or in combination, minimizing the influx to aerial parts. Increasing P fertilizer application rates appears to prevent heavy metal and nitrate translocation to shoot tissues and the edible parts of water spinach on co-contaminated soils. 相似文献
130.
Prabhat Kumar Nigam 《Indian journal of clinical biochemistry : IJCB》2016,31(2):237-239
The negative interference by bilirubin in serum creatinine estimation by Jaffe’s kinetic method is well known. Several approaches have been suggested to overcome this interference. In this article three different creatinine kits (Jaffe’s kinetic method) have been tested for bilirubin interference and its rectification using two simple approaches. The performance of three kits (A, B and C) supplied by three different manufacturers was tested using IQC and EQAS sera and pooled serum with added bilirubin. To overcome the bilirubin interference two approaches viz. NaOH preincubation and TCA precipitation were used. Bilirubin did interfere in creatinine estimation after a certain level (2.3 mg/dl). However, both NaOH preincubation and TCA precipitation approach rectified this interference. The performance of kit A was better than kit B and C. All the three kits showed bilirubin interference upon increasing the bilirubin concentration but kit A performed better than kit B and C. However, NaOH incubation and TCA precipitation methods overcame this interference to a great extent. 相似文献