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51.
1 Introduction 1 High temperature air combustion (HTAC) [1] can offer significantly improved thermal efficiency, reduced NOx emission and uniform heat flux field. Most of HTAC use the honeycomb regenerative system to preheat the air to a temperature above… 相似文献
52.
Donna Chamely-Wiik Brian T. Cooney Michael A. DeDonno 《Mentoring & Tutoring: Partnership in Learning》2020,28(1):78-97
ABSTRACTIn this study, we investigated a profile of faculty who mentor undergraduate researchers at a four-year Hispanic-serving, public research university. Six variables were investigated: ethnicity, gender, age, tenure status, teaching evaluations, and research productivity. Data were compiled from institutional databases. Findings showed a greater percentage of tenured faculty mentoring undergraduate researchers while the percent of minority UR faculty mentors was consistent with institutional percentages. Additionally, findings included a higher percentage of Science, Technology, Engineering, and Math (STEM) Undergraduate Research (UR) underrepresented minority faculty mentors compared to STEM Institution (INST) underrepresented minority faculty. For research productivity, UR faculty mentor funding comprised 28.0% of all external grant awards and 36.0% of all external funding during the sampling period. The majority funding for INST and UR faculty were found to be in the STEM disciplines. These findings provide evidence of potential predictors to describe UR faculty mentor profiles and can be considered important information for determining future educational policies and practices. 相似文献
53.
This study explored and compared the perspectives of Taiwanese in-service and pre-service high school mathematics teachers regarding ideal teaching behaviours; the perspectives of a nationwide sample of students were taken as the baseline. Fourteen factors contributing to ideal teaching behaviours were identified through exploratory factor analyses. Nine factors, including idea explanation and speedy lecture, were rooted in traditional Chinese culture; five factors, including concrete representation and student activities, were influenced by Western cultures. Three teacher profiles were identified through k-means clustering analysis. The perspectives of in-service teachers were dominated by a painless meaning-emphasised profile; these teachers emphasised meaningful learning for students and avoided the fast pace and demanding requirements that can cause distress in students, whereas pre-service teachers were dominated by an all-round profile, revealing their openness to all factors. Compared with pre-service teachers, in-service teachers’ perspectives were more similar to those of students. 相似文献
54.
M. I. Akpanabiatu I. B. Umoh E. O. Udosen A. E. Udoh E. E. Edet 《Indian journal of clinical biochemistry : IJCB》2005,20(2):29-34
Aqueous extract of the leaf and root ofNauclea latifolia Sm. (Rubiaceae) is used in Nigerian folk medicine for the treatment of hypertension. This work is carried out to investigate
the effect ofNauclea latifolia leaf extract on lipid profile and cardiovascular activity of rats. Normal and 10% coconut oil fed rats were treated with
the water-soluble fraction of the ethanol extract ofNauclea latifolia leaf for 2 weeks. Forty-eight mature male albino rats of the Wistar strain were divided into two experiments of four groups,
each group having 6 animals. Experiment I animals were treated with the water-soluble fraction of the ethanol extract whilst
experiment II animals were fed 10% coconut oil meal before treatment with the water-soluble fraction of the ethanol extract.
A single oral dose ofNauclea latifolia was 170, 340 and 510 mg/kg body wt/day of the extracts respectively for 2 wks. There was no significant change in the lipid
profile of the experimental animals as compared with the controls. There was about 40% relaxation on contracted thoracic aorta
that was pre-contracted with 2 μM phenylephrine. The viability of the tissue was tested against 10 μM of acetylcholine. There
was no significant (P>0.05) change in Na+ concentration in the serum. However, the K+ concentration in the serum of the experimental animals showed a significant increase. The study shows that ethanol extract
ofNauclea latifolia has vasodilator action on the aorta and that lipid profiles of experimental rats were not affected. Furthermore, the increase
in the K+ may be contributing to the vasodilator effect ofNauclea latifolia. 相似文献
55.
K. A. Faseehuddin Shakir Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2007,22(2):129-131
Antioxidant property of flaxseed chutney was evident by decreasing lipid peroxidation (TBARS) and predictor enzyme γ-glutamyl
transpeptidase profile and micronuclei formation in azoxymethane treated rats. After 10 weeks, rats fed with either fiber-free
basal diet or Antioxidant diet exhibited over sevenfold increase in γ-glutamyl transpeptidase activity and nearly fourfold
increase in micronuclei load in comparison to controls (p<0.001). A significant reduction in both γ-glutamyl transpeptidase
level (52%) and micronuclei formation (47%) was observed in fiber-free basal diet/Antioxidant diet/flaxseed chutney diet fed
rats. Relative to rats fed fiber-free basal diet, the profile of γ-glutamyl transpeptidase and micronuclei load was not significantly
altered. 相似文献
56.
从煤矿的实际需求及GIS的特性出发,阐明了系统设计的总体流程、模块设计、系统开发组件与环境;着重对等值线及剖面图生成(钻孔见煤深度、软煤层厚的表面、平面和立体等值线以及剖面生成)做了介绍,并给出了系统功能界面。 相似文献
57.
Although the ways that immigrants relate to UK culture has been a hot topic since the EU-referendum, little attention has been given to how majority group members such as Host Country Nationals (HCNs) relate to immigrants’ culture. Thus, we explored English HCNs’ globalisation-based proximal-acculturation – the extent to which they prefer to adopt aspects of immigrants’ cultures and/or maintain their national culture. Using two-step cluster analysis, a pilot study (N = 63) revealed a separated, integrated, and undifferentiated cluster, with separated HCNs perceiving cultural diversity more as a threat and less as an enrichment. Using latent profile analysis in a second study (N = 220) also revealed a three strategy-solution, identifying assimilated, integrated and separated profiles. Again we examined how these strategies differed across perceptions of cultural threat and enrichment as well as other psychosocial characteristics: identifying with fellow English citizens, recognizing cultural differences whilst not being culturally embedded (constructive marginalization), and various forms of intergroup contact. Separated HCNs identified more with fellow English citizens, endorsed less constructive marginalization, perceived less cultural enrichment yet more cultural threat than HCNs following some of the other strategies. These results stress that the onus of cultural adoption lies with both groups – minorities and majority members – with English HCNs showing distinct proximal-acculturation strategies. Lastly, when exploring a variable-centred approach, proximal-acculturation orientations (cultural maintenance/adoption) mediated the relationship between cultural threat, cultural enrichment, and intergroup contact on positive feelings towards immigrants. Thus, the ways that HCNs acculturate may provide a new route towards harmonious intergroup relations. 相似文献
58.
59.
The study of measurement invariance in latent profile analysis (LPA) indicates whether the latent profiles differ across known subgroups (e.g., gender). The purpose of the present study was to examine the impact of noninvariance on the relative bias of LPA parameter estimates and on the ability of the likelihood ratio test (LRT) and information criteria statistics to reject the hypothesis of invariance. A Monte Carlo simulation study was conducted in which noninvariance was defined as known group differences in the indicator means in each profile. Results indicated that parameter estimates were biased in conditions with medium and large noninvariance. The LRT and AIC detected noninvariance in most conditions with small sample sizes, while the BIC and adjusted BIC needed larger sample sizes to detect noninvariance. Implications of the results are discussed along with recommendations for future research. 相似文献
60.
This study compared the neuromuscular, metabolic and hormonal profiles of trained prepubescent tennis players and an untrained group. The boys in the experimental group (n = 9; mean age ± S.D. = 11.4 ± 0.5 years) had participated in tennis training for 2.3 ± 1.0 years and the boys in the control group (n = 9; mean age ± S.D. = 10.9 ± 0.4 years) were normal active volunteers. The tennis players were found to be physically more active than the controls when the comparison was made for either 1 year (4.9 ± 1.8 vs 2.6 ± 2.5 times per week; P<0.05) or for 1 week (3.4 + 1.2 vs 0.4 ± 0.5 times; P < 0.001) preceding the tests. Choice reaction time was significantly (P <0.01) shorter in the experimental group (258 ± 16 ms) than in the control group (344 + 81 ms). Dropping height in the best drop jump was significantly (P< 0.05) higher in the tennis players (0.46 + 0.19 m) than in the control boys (0.27 ± 0.10 m). The tennis players had significantly lower oxygen consumption at the ‘anaerobic threshold’ than the controls (P < 0.05). There were no significant differences between the groups in serum hormone levels. The small differences that existed may have been caused by actice participation in sport by the tennis players. 相似文献