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951.
952.
This paper describes a method of analysing teacher growth in the context of science education. It focuses on the identification of pathways in the development of secondary school teachers’ pedagogical content knowledge (PCK) by the use of the interconnected model of teachers’ professional growth (IMTPG).The teachers (n = 12) participated in a one-year action research project focused on their individual concerns related to teaching science. The use of the IMTPG revealed that teachers use different pathways of learning to develop different aspects of their PCK. For each PCK component, three distinct pathways could be identified, two of which clearly were associated with professional growth. When examining these two pathways in detail, it was found that (1) teachers learned about new instructional strategies and assessment methods mostly through literature reviews and discussions with peers and (2) teachers who analyzed and reflected on student learning as it happened in their classrooms developed understandings that helped them to select and apply instructional strategies to further promote student learning. Both the analytical method as well as the identification of the different developmental pathways help to better understand teacher development in the context of classroom practices. 相似文献
953.
Tobias H. Stark Lars Leszczensky Sebastian Pink 《Zeitschrift für Erziehungswissenschaft》2017,20(3):475-498
Research has established that adolescents both befriend peers based on their academic achievement and adjust their own achievement to that of their friends’ over time. However, these processes may be different for ethnic minority students, because some of them may adhere to an oppositional culture that rejects striving for academic success. We examine respective differences between self-identified ethnic minority and majority students using longitudinal social network analysis (stochastic actor-oriented models) in a sample of 1175 students (aged 13) from 12 grade-level networks in Germany secondary schools. Among the students, we find that academically successful students in particular prefer friends with high grades, but that students with poor grades exert more social influence on their friends to adjust their performance. Moreover, while minority students are indeed less inclined to select friends with higher grades, both ethnic majority and minority youth prefer friends with similar academic achievement and are similarly influenced by their friends’ achievement. However, social influence is stronger from same-ethnic than from inter-ethnic friends. In sum, there is mixed evidence for an oppositional culture among ethnic minority students in our sample. 相似文献
954.
H. Alix Gallagher Nicole Arshan Katrina Woodworth 《Journal of research on educational effectiveness》2017,10(3):570-595
By 2013, all 50 states and the District of Columbia had adopted college- and career-ready standards in English language arts and mathematics, placing a greater emphasis on argument writing to prepare students for life after high school. Solving the specific problem of how to help teachers teach to new standards for argument writing as well as the broader problem of improving teaching and learning requires continued efforts to understand how to support teachers in making substantial changes in instruction. This paper reports on a district-randomized controlled trial of the National Writing Project's College-Ready Writers Program (CRWP), implemented in high-need rural districts in 10 states, testing one instance of professional development paired with supporting curricular resources and a formative assessment tool designed to shift instruction to align with the new college- and career-ready standards in English language arts classes in Grades 7–10. Researchers randomly assigned 44 rural districts either to receive two years of CRWP or to be in a business-as-usual control group and found positive impacts on teacher practice and student source-based argument writing. 相似文献
955.
An optical transparent 3-D Integrated Microchannel-Electrode System (3-DIMES) has been developed to understand the particles'' movement with electrokinetics in the microchannel. In this system, 40 multilayered electrodes are embedded at the 2 opposite sides along the 5 square cross-sections of the microchannel by using Micro Electro-Mechanical Systems technology in order to achieve the optical transparency at the other 2 opposite sides. The concept of the 3-DIMES is that the particles are driven by electrokinetic forces which are dielectrophoretic force, thermal buoyancy, electrothermal force, and electroosmotic force in a three-dimensional scope by selecting the excitation multilayered electrodes. As a first step to understand the particles'' movement driven by electrokinetic forces in high conductive fluid (phosphate buffer saline (PBS)) with the 3-DIMES, the velocities of particles'' movement with one pair of the electrodes are measured three dimensionally by Particle Image Velocimetry technique in PBS; meanwhile, low conductive fluid (deionized water) is used as a reference. Then, the particles'' movement driven by the electrokinetic forces is discussed theoretically to estimate dominant forces exerting on the particles. Finally, from the theoretical estimation, the particles'' movement mainly results from the dominant forces which are thermal buoyancy and electrothermal force, while the velocity vortex formed at the 2 edges of the electrodes is because of the electroosmotic force. The conclusions suggest that the 3-DIMES with PBS as high conductive fluid helps to understand the three-dimensional advantageous flow structures for cell manipulation in biomedical applications. 相似文献
956.
957.
Urinary abnormalities were evaluated in 100 renal stone patients with first episode of renal stone having age 22 to 45 years
from both sex and compared to 100 normal healthy control group having same age group from both sex. Twenty-four hours urinary
oxalate, calcium, uric acid, sodium, magnesium, phosphorus and citrate were estimated. The urinary pH was also determined.
In stone formers urinary oxalate, calcium, sodium and uric acid excretions were significantly higher when compared with control
group. Whereas citrate, phosphate and magnesium excretion were significantly lower in stone formers when compared with control.
The pH of urine in stone formers was lower than the controls. High dietary intake of purine rich diet causes elevated excretion
of uric acid, which leads to calcium oxalate crystal formation and precipitation. Other risk factors such as urinary oxalate,
calcium also related to formation of renal calculi.
Hypocitraturia is the main cause of renal calculi along with hypomagnesiuria and hypophosphaturia in the patient of Marathwada
region. On the basis of urinary abnormalities further stone formation in the patient can be prevented by dietary modifications. 相似文献
958.
Ajay Kumar D. H. Shah M. G. R. Rajan U. R. Thakare S. M. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):159-164
An external quality assessment was conducted to assess the performance of various laboratories for RIA of thhyroid related
hormones in two phases. In the first phase thirty five laboratories participated. At the end of first phase a meeting cum
workshop was organised to discuss the results of first phase, difficultires faced by the participants and pinpoint the short
oming. A second phase was then initiated with an objective of improvement in the performance, if any, where twelve samples
from four pools were distributed to twenty four laboratories who participated for the second phase. The overall return of
the results increased significantly from 71.8% (1586/2208) for the first phase to 92.4% (732/792) for the second phase. The
inter laboratory %CV for T3, T4 and TSH were lower during the second phase (30.6%, 19.0% and 31.6% respectively) as compared to those observed during first
phase (36.3%, 22.7% and 52.8% respectively). Similarly, there was an improvement in reproducibility of ALTM as %CV for T3, T4 and TSH decreased from 6.0%, 9.8% and 13.4% respectively to 4.5%, 4.6% and 8.5% respectively. The individual performances
of the participating laboratories viz. bias, variability of bias and imprecision also showed a trend towards improvement as
percent laboratories having desirable or acceptable results for T3, T4 and TSH increased from 10.7%, 60.7% and 0.0% respectively to 20.8%, 66.7% and 22.2% respectively. External quality assessment
thus appears to be beneficial in assessing the performane of a laboratory in comfparison with other laboratories and indeed
helps in improving the performance. 相似文献
959.
S. K. Bansal H. N. Pandey A. Bansal L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1992,7(2):179-184
Circadian rhythm of serum glucose, pyruvate, lactate and lactate dehydrogenase (LDH) was studied in normal healthy young volunteers
at the onset (I Group, 7 cases) and peak (II Group, 8 cases) of winters in India with highly varied temperature. There was
a significant difference, in the circadian rhythm of glucose, pyruvate and lactate dehydrogenase (LDH) of the two groups.
A clockwise shift was observed in acrophase except in serum lactate, which is related to the energy demand in association
with time qualified changes in diurnal activity of the individuals and change in photoperiod. 相似文献
960.
Seema Gupta Rajesh Pandey Ranjan Katyal H. K. Aggarwal R. P. Aggarwal S. K. Aggarwal 《Indian journal of clinical biochemistry : IJCB》2005,20(1):67-71
The present study was conducted to evaluate some of the components of antioxidant defense system and oxidative damage in 20
male patients of alcoholic liver disease (ALD). The results were compared with 20 healthy male smokers and 20 healthy male
non-smokers volunteers. Patients were subjected to detailed clinical examination and laboratory investigations. Blood samples
were collected for estimating reduced glutathione (GSH), total thiols (T-SH) malondialdehyde (MDA), transaminases (AST, ALT),
glutathione-S-transferease (GST) and gammaglutamyl transferase (GGT). Serum aspartate amino transferase (AST)/alanine amino
transferase (ALT) ratio was significantly (p<0.01) reduced in ALD patients as compared to the controls. However, the core
of utility of MDA and GST was found to be significantly (p<0.01) increased in ALD patients compared to controls. There was
a significant negative correlation of MDA with both GSH and TSH. Plasma GGT levels were significantly (p<0.01) increased in
alcoholics and the enzyme showed a significant positive correlation with MDA. These results give enough evidence of increased
oxidative stress and compromised antioxidant defense system in patients with ALD. 相似文献