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991.
In the present study, we describe a participating student’s (Carol’s) distributive partitioning scheme and operations along with Steffe’s and his colleagues’ studies about children’s constructions of fraction knowledge as a particular model of mathematical learning. Analysis of Carol’s mathematical behaviors indicates that an operationally common mathematical behavior (distributive partitioning operation) was revealed in various mathematical problem situations such as fraction multiplication, fraction division, and multiplicative transformation between fractional quantities. It both provides a rationale for why becoming versed in one mathematical subject could facilitate working with another mathematical subject and also implies the necessity of describing and defining students’ mathematical behaviors from an operational view of knowledge, which might lead to building foundations of a substantial cognitive map for students’ mathematical development.  相似文献   
992.
Adopting Maria Manzon’s theoretical framework, which draws on Foucault and proposes that comparative education as an academic field is socially constructed, I suggest that the field is neither stable nor well defined. To demonstrate this, I conduct a content analysis of the Comparative Education Review, using Klaus Krippendorff’s methodological framework to study comparative and international education (CIE) researchers’ understanding of the national—and of their related knowledge production in the field. Many comparativists express interests in multiple countries, and their knowledge production takes the form of individual country studies. The countries are habitually studied using a “problem approach” focusing on one specific aspect of the country under investigation and using an associated social science methodology deemed appropriate. Few comparativists are making explicit use of or reference to any methodology that is unique to comparative education. Efforts to catalog and systematize CIE research have demonstrated that the field is becoming so inclusive that it hardly is distinguishable from educational studies as a whole. Hence, I suggest that instead of speaking about unifying features of the field, it may be more relevant to speak about frequent elements, such as a focus on the national, and a knowledge production characterized by the academic practitioner who desires to improve the education systems studied. A third frequent element may be the focus on educational development, thus justifying the label of “comparative, international, and development education.” One challenge of the field is its dependence on Western social science discourses, which may be marginalizing other voices.  相似文献   
993.
994.
Students’ affective domain has been popular in the mathematics education community in an ongoing attempt to understand students’ learning behavior. Specifically, enhancing students’ motivation in the mathematics classroom is an important issue for teachers and researchers, due to its relation to students’ behavior and achievement. This paper utilized achievement goal theory—an important theoretical prospect on students’ motivation in school settings—to investigate the existence of a model presenting the relation between motivation and other affective constructs and students’ performance in mathematics. In this regard, two types of tests were administered to 321 sixth grade students measuring their motivation and other affective constructs and their performance in mathematics. Using structural equation modeling, we examined the associations among the affective constructs, motivation, and the extent to which these constructs influence students’ performance and interest in mathematics. The data revealed that students’ performance and their interest in mathematics were influenced by fear of failure, self-efficacy beliefs, and achievement goals. We discuss these findings in terms of teaching implications in the mathematics classroom.  相似文献   
995.
996.
Students with autism may struggle to develop the academic skills necessary for success in school and beyond. Understanding and improving academic skills performance requires appropriate measurement approaches. One such option that has been minimally studied with students with autism is curriculum-based measurement (CBM). Coinciding with the need to study different approaches to academic skills measurement for students with autism was the global pandemic which forced a shift to remote service delivery with little warning. While some autistic students struggled with this shift, others thrived, raising questions about how to further support students with autism in virtual formats. The purpose of this study was to examine the feasibility of using remotely administered CBM for autistic students by studying both the practicality and acceptability of this approach. Five students with autism (Grades 2–5) participated in this pilot study, completing reading, math, and writing CBMs at three time points. Student behavior and assessor fidelity were collected to examine practicality; assessor ratings of usability provided insight regarding the acceptability of the approach. Results indicated that remotely administered CBM is feasible for some students with autism: all participants completed the study tasks with minimal behavioral difficulties, and assessor ratings of acceptability were high.  相似文献   
997.
Alcoholic liver disease (ALD) is due to excessive alcohol intake for long duration. Distinguishing ALD from non-ALD (non-alcoholic steatohepatitis, hepatitis of viral origin) is difficult as patient may deny alcohol abuse. Clinical examination, histology and serology may not differentiate these conditions. Accurate diagnosis is important as management of ALD differs from non-ALD patients. The aim of our study was (1) To evaluate the patients of ALD and non-ALD by biochemical parameters compared to controls, (2) To assess whether these parameters can differentiate ALD from non-ALD. Study was carried out on 50 patients of ALD in group I and 35 patients of NASH (non-alcoholic steatohepatitis) and acute viral hepatitis each in group II. Age matched healthy controls n = 50. Selection criteria—history of alcohol intake (amount and duration), clinical examination, sonography of abdomen, serum alanine transaminase (ALT) and bilirubin levels. Blood samples were analyzed for bilirubin, aspartate transaminase (AST), ALT, alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) by kinetic method. Statistical analysis was done by Student unpaired ‘t’ test. Patients of ALD have raised AST/ALT ratio (De Ritis ratio) (>2), ALP and GGT compared to controls (P < 0.01).There is significant difference in AST/ALT ratio, serum GGT and ALP in ALD group compared to that in NASH and acute viral hepatitis (P < 0.05). This study suggests that De Ritis ratio >2 in ALD patients may be due to alcohol induced hepatic mitochondrial injury and pyridoxine deficiency. High GGT and ALP values may indicate enzyme induction by alcohol and mild cholestasis. Thus ALD patients have severe hepatic damage. De Ritis ratio <1 and normal to mild elevation in GGT level in NASH and acute viral hepatitis suggest mild hepatic injury of non-alcoholic origin. Our study concludes that ALD patients can be differentiated from NASH and acute viral hepatitis with certainty by measuring serum AST/ALT ratio, GGT and ALP. These biochemical parameters may help clinicians to support the diagnosis of ALD and non-ALD.  相似文献   
998.
Basing treatment, policy and planning decisions on the best available research knowledge remains a central principle in modern health care around the world, yet many health professionals find acquiring and managing published research knowledge challenging. In this paper, we report on a Soft Systems Methodology-based collaborative action research initiative with a specialist mental health service from the United Kingdom's National Health Service. Our objective was to design and implement improvements to their knowledge acquisition and management activities in order to facilitate sustained and effective evidence-based practices. We report on both the factors found to impede effective research knowledge acquisition and management and the development of more integrated knowledge management processes designed to improve the situation.  相似文献   
999.
Droplet-based microfluidics has gained extensive research interest as it overcomes several challenges confronted by conventional single-phase microfluidics. The mixing performance inside droplets/slugs is critical in many applications such as advanced material syntheses and in situ kinetic measurements. In order to understand the effects of operating conditions on the mixing performance inside liquid slugs generated by a microfluidic T-junction, we have adopted the volume of fluid method coupled with the species transport model to study and quantify the mixing efficiencies inside slugs. Our simulation results demonstrate that an efficient mixing process is achieved by the intimate collaboration of the twirling effect and the recirculating flow. Only if the reagents are distributed transversely by the twirling effect, the recirculating flow can bring in convection mechanism thus facilitating mixing. By comparing the mixing performance inside slugs at various operating conditions, we find that slug size plays the key role in influencing the mixing performance as it determines the amount of fluid to be distributed by the twirling effect. For the cases where short slugs are generated, the mixing process is governed by the fast convection mechanism because the twirling effect can distribute the fluid to the flow path of the recirculating flow effectively. For cases with long slugs, the mixing process is dominated by the slow diffusion mechanism since the twirling effect is insufficient to distribute the large amount of fluid. In addition, our results show that increasing the operating velocity has limited effects on improving the mixing performance. This study provides the insight of the mixing process and may benefit the design and operations of droplet-based microfluidics.  相似文献   
1000.
This study proposes a novel cell collection method based on collagenase treatment and ultrasonic vibration. The method collects calf chondrocytes from a reusable metal cell culture substrate. To develop our concept, we calculated the natural vibration modes of the cell culture substrate by a finite element method, and conducted eigenvalue and piezoelectric-structural analyses. Selecting the first out-of-plane vibration mode of the substrate, which has a single nodal circle, we designed and fabricated the cell collection device. The excited vibration mode properly realized our intentions. We then evaluated the cell collection ratio and the growth response, and observed the morphology of the collected cells. The collagenase and ultrasonic vibration treatment collected comparable numbers of cells to conventional trypsin and pipetting treatment, but improved the proliferating cell statistics. Morphological observations revealed that the membranes of cells collected by the proposed method remain intact; consequently, the cells are larger and rougher than cells collected by the conventional method. Therefore, we present a promising cell collection method for adhesive cell culturing process.  相似文献   
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