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21.
Bibhas Roy Gautam Chattopadhyay Debasish Mishra Tamal Das Suman Chakraborty Tapas K. Maiti 《Biomicrofluidics》2014,8(3)
An on-chip lectin microarray based glycomic approach is employed to identify glyco markers for different gastritis and gastric cancer. Changes in protein glycosylation have impact on biological function and carcinogenesis. These altered glycosylation patterns in serum proteins and membrane proteins of tumor cells can be unique markers of cancer progression and hence have been exploited to diagnose various stages of cancer through lectin microarray technology. In the present work, we aimed to study the alteration of glycan structure itself in different stages of gastritis and gastric cancer thoroughly. In order to perform the study from both serum and tissue glycoproteins in an efficient and high-throughput manner, we indigenously developed and employed lectin microarray integrated on a microfluidic lab-on-a-chip platform. We analyzed serum and gastric biopsy samples from 8 normal, 15 chronic Type-B gastritis, 10 chronic Type-C gastritis, and 6 gastric adenocarcinoma patients and found that the glycoprofile obtained from tissue samples was more distinctive than that of the sera samples. We were able to establish signature glycoprofile for the three disease groups, that were absent in healthy normal individuals. In addition, our findings elucidated certain novel signature glycan expression in chronic gastritis and gastric cancer. In silico analysis showed that glycoprofile of chronic gastritis and gastric adenocarcinoma formed close clusters, confirming the previously hypothesized linkage between them. This signature can be explored further as gastric cancer marker to develop novel analytical tools and obtain in-depth understanding of the disease prognosis. 相似文献
22.
Zhi‐Hong Chen Chih‐Yueh Chou Gautam Biswas Tak‐Wai Chan 《British journal of educational technology : journal of the Council for Educational Technology》2012,43(2):247-258
Although competition is regarded as a powerful motivator in game‐based learning, it might have a negative influence, such as damage to confidence, on students who lose the competition. In this paper, we propose an indirect approach, substitutive competition, to alleviate such negative influences. The approach is used to develop a My‐Pet v3 system, in which pupils master subject materials to make their pets stronger, and compete against each other. Specifically, pupils learn Chinese idioms in a pet‐training game scenario, and their mastery of the material is related to the pets' strength to win the competition. The result of the competition is influenced by whether pupils spend enough effort on the learning tasks. This intention is expected to alleviate the negative influence that results from direct competition. A within‐subject experiment was conducted to examine the influence of substitutive competition. The results indicated that substitutive competition seems a promising scheme to maximise the power of competition. However, there were no apparent evidences in this study to demonstrate its effect to alleviate pupils' sense of failure, as compared with other two direct competition conditions. 相似文献
23.
Gautam Puhan 《Journal of Educational Measurement》2012,49(3):312-329
Tucker and chained linear equatings were evaluated in two testing scenarios. In Scenario 1, referred to as rater comparability scoring and equating, the anchor‐to‐total correlation is often very high for the new form but moderate for the reference form. This may adversely affect the results of Tucker equating, especially if the new and reference form samples differ in ability. In Scenario 2, the new and reference form samples are randomly equivalent but the correlation between the anchor and total scores is low. When the correlation between the anchor and total scores is low, Tucker equating assumes that the new and reference form samples are similar in ability (which, with randomly equivalents groups, is the correct assumption). Thus Tucker equating should produce accurate results. Results indicated that in Scenario 1, the Tucker results were less accurate than the chained linear equating results. However, in Scenario 2, the Tucker results were more accurate than the chained linear equating results. Some implications are discussed. 相似文献
24.
Gautam Puhan Timothy P. Moses Mary C. Grant Frederick McHale 《Journal of Educational Measurement》2009,46(3):344-362
A single-group (SG) equating with nearly equivalent test forms (SiGNET) design was developed by Grant to equate small-volume tests. Under this design, the scored items for the operational form are divided into testlets or mini tests. An additional testlet is created but not scored for the first form. If the scored testlets are testlets 1–6 and the unscored testlet is testlet 7, then the first form is composed of testlets 1–6 and the second form is composed of testlets 2–7. The seven testlets are administered as a single administered form, and when a sufficient number of examinees have taken the administered form, the second form (testlets 2–7) is equated to the first form (testlets 1–6) using an SG equating design. As evident, this design facilitates the use of an SG equating and allows for the accumulation of data, both of which may reduce equating error. This study compared equatings under the SiGNET and common-item equating designs and found lower equating error for the SiGNET design in very small sample size conditions (e.g., N = 10). 相似文献
25.
Gautam Puhan Timothy P. Moses Lei Yu Neil J. Dorans 《Journal of Educational Measurement》2009,46(1):59-83
This study examined the extent to which log-linear smoothing could improve the accuracy of differential item functioning (DIF) estimates in small samples of examinees. Examinee responses from a certification test were analyzed using White examinees in the reference group and African American examinees in the focal group. Using a simulation approach, separate DIF estimates for seven small-sample-size conditions were obtained using unsmoothed (U) and smoothed (S) score distributions. These small sample U and S DIF estimates were compared to a criterion (i.e., DIF estimates obtained using the unsmoothed total data) to assess their degree of variability (random error) and accuracy (bias). Results indicate that for most studied items smoothing the raw score distributions reduced random error and bias of the DIF estimates, especially in the small-sample-size conditions. Implications of these results for operational testing programs are discussed. 相似文献
26.
Since organic solid state reactions must take place within the organised medium of the crystal lattice, their course and outcome can often be controlled and exploited. Although their major application is not in the area of organic synthesis, they are far from being academic curiosities. They have been involved in situations as diverse as observing the approach of reacting molecules, determining the absolute configurations of chiral molecules, and establishing crystallisation patterns for organic solids. 相似文献
27.
Mehtab Alam Ansari Gautam J. N. Shahwar Fatima 《Cataloging & classification quarterly》2017,55(4):247-265
The purpose of this article is to highlight the status and application of an automated cataloging system in central university libraries in north India. Data has been collected using questionnaires. Interview and observation techniques have also been used to bring objectivity in the present study. Results show that varying levels of progress have been made with respect to implementation of a cataloging system. Results also show that with the help of automation, libraries have satisfied user communities by way of easy retrieval. It has removed discrepancies and set a trend for standardization. Furthermore, staff morale has been boosted up in an automated environment. 相似文献
28.
In the present work, Dirac delta function (DF) set and sample-and-hold functions (SHF) set are used for microprocessor-based simulation of discrete time as well as sample-and-hold systems. Such simulations are useful for identification of control systems with known input and output sequence. The presented method utilizes operational matrices of different orders in the DF and SHF domain to develop different operational transfer functions. A few open-loop as well as closed-loop systems have been studied and the simulation results obtained are compared with exact solutions derived with the help of z-transform analysis. Experiments have also been carried out to establish the validity of the proposal. 相似文献
29.
Baine David Puhan Biranchi Puhan Gautam Puhan Siba 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2000,46(1-2):49-66
The paper describes a curriculum development pilot study in a rural village in India. The purpose of the study was to develop and test application of an ecological inventory approach to curriculum development integrating academic and functional skill training. Ecologically valid curricula teach the knowledge, skills, attitudes and values required by students to function effectively in current and future environments (e.g., urban and/or rural, academic, vocational, domestic, community and recreational) in which the students perform. The discussion illustrates application of ecological inventories and describes several related data collection instruments and procedures. The paper also describes an Integrated Core Curriculum Structure (ICCS) as a guide for designing curricula based on ecological inventories. An example is provided of a practical Thematic Unit Plan derived from the ICCS and integrating a variety of functional and academic skills into a guide for instruction and evaluation. The discussion provides a clear insight into many of the problems faced by students, school leavers and graduates in rural areas of developing countries, both in their daily lives and as they plan for their futures. 相似文献
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