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91.
92.
Mulberry longicorn beetle, Apriona germari, has been reported to produce two endo-β-l,4-glucanases or AgEGases (accession Nos. Q6SS52 and Q5XQD1). AgEGase sequence contains catalytic motif (amino acid residues 37~48), which is the characteristic of family Glycohydrolase 45 and is identified as the substrate binding site. The application of bioinformatics approaches includes sequence analysis, structural modeling and inhibitor docking to relate the structure and function of AgEGases.We have dissected the sequence and structure of AgEGase catalytic motif and compared it with crystal structure of Humicola insolens endoglucanases Ⅴ. The results show an involvement of sulfur containing amino acid residues in the active site of the enzyme. Cys residues and position of disulfide bonds are highly conserved between the two structures of endoglucanases of A.germari. Surface calculation of AgEGase structure in the absence of Cys residues reveals greater accessibility of the catalytic site to the substrate involving Asp42, a highly conserved residue. For the inhibition study, tannin-based structure was docked into the catalytic site of AgEGase using ArgusLab 4.0 and it resulted in a stable complex formation. It is suggested that the inhibition could occur through formation of a stable transition state analog-enzyme complex with the tannin-based inhibitor, as observed with other insect cellulases in our laboratory.  相似文献   
93.
The educational history of the Sultanate of Oman has undergone rapid development. In 1970, there were three primary schools. Today, there is universal education, with modern public and private institutions. In 1985, the first teacher education institutions offered a diploma programme. In 1994, six Colleges of Education, offering a degree, were established. Recently, the Directorate General-Colleges of Education, Ministry of Higher Education, introduced a quality assurance process in these colleges based on self-assessment, external review, feedback, and monitored change. This paper outlines how the process was established, the challenges it presented, and the solutions that have been developed.  相似文献   
94.
This study investigated the relationship between foreign language (FL) anxiety and achievement in that language. The role of the FL teacher as perceived by the learners was also tested. Participants were 67 seventh‐grade students. They were administered an anxiety questionnaire, a Hebrew reading comprehension test, an English reading comprehension test, an English creative writing task, and an English spelling test. The results indicated that anxiety was negatively and significantly correlated to FL achievement on all FL tests. Gender and teachers' attitudes were the only significant predictors of FL anxiety among these seventh‐grade students. The results are discussed in light of findings in the literature. Some recommendations are suggested to ease anxiety in FL students.  相似文献   
95.
The present work demonstrates the use of a dielectrophoretic lab-on-a-chip device in effectively separating different cancer cells of epithelial origin for application in circulating tumor cell (CTC) identification. This study uses dielectrophoresis (DEP) to distinguish and separate MCF-7 human breast cancer cells from HCT-116 colorectal cancer cells. The DEP responses for each cell type were measured against AC electrical frequency changes in solutions of varying conductivities. Increasing the conductivity of the suspension directly correlated with an increasing frequency value for the first cross-over (no DEP force) point in the DEP spectra. Differences in the cross-over frequency for each cell type were leveraged to determine a frequency at which the two types of cell could be separated through DEP forces. Under a particular medium conductivity, different types of cells could have different DEP behaviors in a very narrow AC frequency band, demonstrating a high specificity of DEP. Using a microfluidic DEP sorter with optically transparent electrodes, MCF-7 and HCT-116 cells were successfully separated from each other under a 3.2 MHz frequency in a 0.1X PBS solution. Further experiments were conducted to characterize the separation efficiency (enrichment factor) by changing experimental parameters (AC frequency, voltage, and flow rate). This work has shown the high specificity of the described DEP cell sorter for distinguishing cells with similar characteristics for potential diagnostic applications through CTC enrichment.  相似文献   
96.
Promoting Acceleration of Comprehension and Content through Text (PACT) and similar team-based models directly engage and support students in learning situations that require cognitive elaboration as part of the processing of new information. Elaboration is subject to metacognitive control, as well (Karpicke, Journal of Experimental Psychology: General 138(4):469–485, 2009)—successful learners use metacognitive elaborative rehearsal to process and make sense of incoming information even in the absence of structured opportunities or instructional prompts for elaborating. Levels of processing and cognitive load theories suggest that students in PACT classrooms may outperform students in comparison classes because PACT engages and supports deep cognitive processing (via elaboration and discussion) at the time of learning, allowing participants to better conserve and more consistently reallocate cognitive and metacognitive resources (compared to students in the non-treated group) for encoding content. In other words, PACT may moderate the relationship of metacognitive elaborative rehearsal and content retrieval. Extant data from years 1 (n?=?419) and 2 (n?=?704) of the PACT/RFU project suggests such an effect. As hypothesized, there were no mean differences in reported metacognitive rehearsal use across the groups because metacognitive elaborative rehearsal was not taught. However, regression coefficients for content recall on metacognitive elaboration were greater in the treatment group in both samples suggesting that an instructional emphasis on deep processing leads to better content recall. The findings are discussed in the context of the Common Core State Standards and the large-scale testing programs in place currently across the USA.  相似文献   
97.
The main objective of this study was to examine the job satisfaction levels of Jordanian kindergarten teachers in relation to work-related dimensions and socio-demographic variables. The sample consisted of 264 randomly selected teachers working in private kindergartens in Amman. To meet the study’s objectives, a two part questionnaire was developed soliciting information about (1) teachers’ age, marital status, and level of education, and (2) level of satisfaction with the physical environment, school relations, working conditions, children’s behavior, and parent participation. The findings of this study revealed that Jordan’s kindergarten teachers experience an overall average level of job satisfaction. While teachers were highly satisfied with their kindergarten classroom physical environments and their relationships within the school, teachers reported average satisfaction levels with their working conditions, children’s social behaviors, and parent participation. Significant relations were found between teachers’ personal-related dimensions and job satisfaction. Several recommendations are made including a call for regulating the working conditions in the kindergarten private sector in accordance with existing international policies that promote teachers’ job satisfaction.  相似文献   
98.
This study was conducted to investigate the diagnostic performance characteristics of prostate specific antigen (PSA) by comparing serum PSA value with histological findings in patients suspevted of having prostate cancer in Aminu Kano Teaching Hospital. Nigeria. Clinical and Laboratory records were examined and collated for serum PSA values, together with histological findings of biopsy specimen, clinical diagnosis, age of patients, and mode of presentation. The serum PSA values were determined by ELECSYS 1010 autoanalysers Roche, Germany based on electrochemiluminescence immunoassay technique. The results show that serum PSA values increase with age in the assymptomatic non-cancer patients who came for medical check up but were within normal limit. In prostatic disease conditions PSA values were raised in benign prostatic hyperplasia 35.957± 4.0315ng/ml, in undifferentiated carcinoma 56.22±4.295ng/ml and adenocarcinoma >100ng/ml as compared to the normal range (0–4ng/ml). These cases were confirmed by histological diagnosis. It is concluded that PSA evaluations is a sensitive marker for prostate cancer but because of various other conditions that affect serum PSA concentration, other methods of investigations such as Digital Rectal examination, Trans Urethral Ultra-Sonography and histological examination should be combined to confirm diagnosis. Prognosis of patients will be better if early diagnosis is made.  相似文献   
99.
Children with autism often show a lack of the interactive social skills that would allow them to engage with others successfully. They therefore frequently need training to aid them in successful social interaction. Video modelling is a widely used instructional technique that has been applied to teach children with developmental disabilities such as autism, and has been shown to be effective in teaching a variety of skills. The aim of this study is to evaluate the impact of video modelling on social skills development in children with autism living in the United Arab Emirates. The research was carried out by Mohammed Alzyoudi, AbedAlziz Sartawi and Osha Almuhiri, all from the United Arab Emirates University. A sample of five boys with autism was chosen to participate in this study. The boys ranged in age between five and seven years. Each child was asked to watch a videotape which presented two individuals interacting in a role‐play setting. One person portrayed a therapist giving cues, while the second portrayed a child acting appropriately and demonstrating correct social behaviours. The boys were then asked to complete a social task and their performance was compared against baseline assessment measures. The results of this study indicate that this is an effective instruction method. Results are discussed and implications for further research and practice are provided.  相似文献   
100.
The effects of the mechanical factors with applied loads on the tribological performance of refined, bleached and deodorised (RBD) palm stearin (PS) were studied using a four-ball tribotester. All the RBD PS results were simultaneously compared with the additive-free paraffinic mineral oil (PMO). The experiments were carried out using different loads with a constant speed in order to gain a better understanding of the mechanical processes that occurred during the experiment. For each experiment, the temperature was increased to 75 °C and was run for 1 h. In a mechanical system, lubricant plays an important role in reducing wear and friction. PS exists as a semi-solid at room temperature after the fractionation process from oil palm. Due to the increasing rate of pollution to the environment, vegetable oil was chosen as the test lubricant with regard to its biodegradability. Other advantages of vegetable oil are that it is more easily harvestable and non-toxic compared to petroleum-based oil, which made it a suitable candidate. From the experiment, RBD PS is found to have a better friction constraint reduction compared with additive-free PMO.  相似文献   
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