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1.
Pleurotus sajor-caju (Fr.) Singer was cultivated on selected agro wastes viz. cotton stalks, groundnut haulms, soybean straw, pigeon pea stalks and leaves and wheat straw, alone or in combinations. Cotton stalks, pigeon pea stalks and wheat straw alone or in combination were found to be more suitable than groundnut haulms and soybean straw for the cultivation. Organic supplements such as groundnut oilseed cake, gram powder and rice bran not only affected growth parameters but also increased yields. Thus bioconversion of lignocellulosic biomass by P. sajor-caju offers a promising way to convert low quality biomass into an improved human food.  相似文献   
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Several studies have found that older women report lower self-rated health than men. However, it is not clear why older women are more likely to report poor self-rated health than older men. Data for this study came from a national cross-sectional survey, Mental Health and Quality of Life of Older Malaysians (MHQoLOM). Included in the survey were 2980 respondents consisting of Malaysians aged 60 years and over, with both men (n = 1428) and women (n = 1552) represented. Results of t-tests showed older men expressed significantly higher levels of self-rated health and self-esteem than women (p < .01). Separate multivariate regression by gender revealed that age, life-threatening problems, and self-esteem were highly significant predictors of self-rated health among older men and women and explained 18.4% of variance in self-rated health for men and 18.2% for women. In the last step we examined the main effects of gender on self-rated health using General Linear Models (GLM) Univariate by adjusting for age, life-threatening problems, and self-esteem. Results showed an insignificant difference in self-rated health between older men and women (F (1,2715) = 2.26, P = 0.13) only after adjusting for self-esteem. It can be concluded that self-esteem affects responses to self-rated health of older men and women.  相似文献   
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Pedagogical content knowledge (PCK) is a type of teacher knowledge to be developed by a teacher. PCK is said to contribute to effective teaching. Most studies investigated the development of PCK and its influence on students’ learning from the teachers’ perspectives. Only a limited number of studies have investigated the components of science teachers’ PCK that helped students’ learning from the perspective of students. Thus, it is the aim of this study to investigate the level of science teachers’ PCK from students’ perspective, in particular whether or not students of different achieving ability had different views of teachers’ PCK in assisting their learning and understanding. Based on the PCK research literature, six components of PCK have been identified, which were as follows: (1) subject matter knowledge, (2) knowledge of teaching strategies, (3) knowledge of concept representation, (4) knowledge of teaching context, (5) knowledge of students, and (6) knowledge of assessment in learning science. A questionnaire consisting of 56 items on a five-point Likert-type scale were used for data collection from 316 Form Four students (16 years old). One-way analysis of variance revealed that the differences in science teachers’ PCK identified by students of different achieving abilities were statistically significant. Overall, students of various academic achieving abilities considered all the components of PCK as important. The low-achieving students viewed all the components of PCK as being less important compared to the high and moderate achievers. In particular, low-achieving students do not view ‘knowledge of concept representation’ as important for effective teaching. They valued the fact that teachers should be alert to their needs, such as being sensitive to students’ reactions and preparing additional learning materials. This study has revealed that PCK of science teachers should be different for high and low-achieving students and knowledge of students’ understanding plays a critical role in shaping teachers PCK.  相似文献   
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Teachers always played a significant role in the intellectual and moral development of students by using various techniques, assessments, and methods to improve student achievement in school's subjects. This study therefore focuses on the effect of teacher factors, such as assessment interval, communication language, the distance of residence, and the teacher's personal characteristics (gender, age, academic and professional qualification, designation, experience, and in-service training) on the 9th grade students' achievement in three subjects (English, Chemistry, and Mathematics at secondary level). The population of the study is comprised of all "public sector" secondary schools, male and female teachers, and boy and girl students. A total number of 16 secondary schools (eight for boys and eight for girls), 114 secondary school teachers (66 males and 48 females), and 2,404 students (1,400 boys and 1,004 girls) were selected through purposive sampling techniques. Multiple statistical procedures, Spearman and Pearson correlation, mean, and standard deviation were employed to obtain stronger validity to the study. The results of the study identify weak and negative weak relationship between most of the teacher factors and student achievement in three subjects but the relationship between students' background and learning achievement in all three subjects were found positively correlated.  相似文献   
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This paper deals with the leader-following consensus problem of multi-agent systems with the consideration that each agent can only transmit its position state to the neighbors at irregular discrete sampling times. In the proposed algorithm, a continuous-discrete time observer is designed for the continuous estimation of both position and velocity from the discrete position information of the neighbors. These estimated states are then used for designing a continuous control law which solves the leader-following consensus problem. Moreover, the dynamics of the leader is not fixed and can be controlled through an external input. The stability analysis has been carried out by employing the Lyapunov approach which provides sufficient conditions to tune the parameters according to the maximum allowable sampling period. The developed algorithm has been simulated and then tested on an actual multi-robot system consisting of three differential drive wheeled robots. Both simulation and hardware results validate the effectiveness of the control algorithm.  相似文献   
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非常感谢中国联合国教科文组织全国委员会的盛情邀请,对于联合国教科文组织每位成员细致人微的工作,我都赞叹不已。在此,非常感谢你们如此出色的工作,同时与这样的团队及成员合作我感到非常愉快,而且常受益匪浅。我已有七八年的时间没有从事开放与远程学习领域的工作,但我确信这个领域已经取得了长足的发展,因此站在这里我感到有些不安,报告中的不妥之处还请大家谅解。  相似文献   
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Of all the senses, that of taste is perhaps the hardest to define and quantify and elucidation of the underlying mechanisms is unrespondingly difficult. This article describes a conceptual model — at the molecular level — for the four basic taste modalities, using apparent specific volume as a fundamental parameter. It also considers possible practical applications.  相似文献   
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目的:探究桑螵蛸脂类提取物的成分及对铜绿假单胞菌的抗菌和抗生物膜作用。创新点:中国传统中药桑螵蛸一直广泛应用于肾病的治疗,在抗菌领域未见报道,本实验首次证明桑螵蛸脂类提取物对铜绿假单胞菌有明显的抗菌和抗生物膜作用。方法:采用气相色谱-质谱联用技术,测定桑螵蛸脂质提取物的化学成分及其相对比例。采用纸片扩散法和琼脂平板稀释法观察桑螵蛸脂类提取物对铜绿假单胞菌的抑菌效应并测定最小抑制浓度(MIC)。采用结晶紫染色法和扫描电镜(SEM)进行抑制生物被膜的试验。结论:桑螵蛸脂类提取物中含有16种化合物,最丰富的成分分别是倍半萜类化合物、单萜和微量芳香族化合物。桑螵蛸脂类提取物对铜绿假单胞菌的MIC为4 mg/ml,对铜绿假单胞菌生物被膜的抑制作用明显。  相似文献   
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