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151.
Recent advance in medical education is in correlation with the advances in information technology and thus computer-based learning is being increasingly employed. The objective of the present study was to design and evaluate an e-learning module in anatomy and assess the perceptions of students and faculty about this e-learning module. The participating students were randomized into three groups by block stratified randomization and Google groups were created for each of the three groups. The e-learning module was implemented in three sessions by rotating the three groups. Validated questionnaires were sent to faculty and participating students via Google forms to obtain feedback. The results of ANOVA showed that there was a significant difference among the groups in terms of marks obtained with conventional (F = 2.403, P = 0.103), online (F = 6.050, P = 0.005), and blended (F = 5.801, P = 0.006). Post hoc comparisons using the Tukey HSD test, about the gain of knowledge, indicated that the results were insignificant when comparing the conventional group with the online group, but were significant when comparing the blended group with the conventional and online group. The qualitative data regarding the perception of students toward e-learning were analyzed using thematic analysis. The introduction of an interactive e-learning module in anatomy was effective and well received by the students and faculty. The study showed that blended learning has a positive impact on the students' learning by improving cognitive gain and receptive perception for e-learning.  相似文献   
152.
As geospatial missions age, one of the challenges for the usability of data is the availability of relevant and updated metadata with sufficient documentation that can be used by future generations of users to gain knowledge from the original data. Given that remote sensing data undergo many intermediate processing steps, for example, an understanding of the exact algorithms employed and the quality of that data produced could be key considerations for these users. As interest in global climate data is increasing, documentation about older data, their origins, and their provenance are valuable to first-time users attempting to perform historical climate research or comparative analysis of global change. Incomplete or missing documentation could be what stands in the way of a new researcher attempting to use the data. Therefore, preservation of documentation and related metadata is sometimes just as critical as the preservation of the original observational data. The Goddard Earth Sciences–Data and Information Service Center (GES DISC), a NASA Earth science Distributed Active Archive Center (DAAC) that falls under the management structure of the Earth Science Data and Information System (ESDIS), is actively pursuing the preservation of all necessary artifacts needed by future users.

In this article, we will detail the data custodial planning and the data lifecycle process developed for content preservation, and our implementation of a Preservation System to safeguard documents and associated artifacts from legacy (older) missions, as well as detail lessons learned regarding access rights and confidentiality of information issues. We also elaborate on key points that made our preservation effort successful; the primary points being drafting of a governing baseline for historical data preservation from satellite missions and using the historical baseline as a guide to content filtering of what documents to preserve. The Preservation System currently archives documentation content for High Resolution Dynamics Limb Sounder (HIRDLS), Upper Atmosphere Research Satellite (UARS), Total Ozone Mapping Spectrometer (TOMS) mission data, and the 1960s era Nimbus mission. Documentation from other missions like the Tropical Rainfall Measuring Mission (TRMM), the Ozone Monitoring Instrument (OMI), and the Atmospheric Infra-Red Sounder (AIRS) are also slated to be added to this repository, as well as other mission datasets to be preserved at the GES DISC.  相似文献   
153.
In traditional medicine, Eucalyptus globulus (eucalyptus) was used for the treatment of diabetes mellitus. Hyperglycemia in diabetes has been associated with increased formation of reactive oxygen species (ROS) and oxidative damage to tissue compounds. The aim of this study was to evaluate the effects of eucalyptus in the diet (20 g/Kg) and drinking water (2.5 g/L) on lipid peroxidation, protein oxidation and antioxidant power in plasma and liver homogenate, as well as glycated-Hb (HbA1C) of blood in streptozotocin-induced diabetic rats for a period of 4 weeks. Diabetes induced in rats by a single intraperitoneal injection of streptozotocin (STZ, 65 mg/Kg). At the end of the treatment period, the level of plasma glucose, plasma and liver malondialdehyde (MDA, the main product of lipid peroxidation), protein carbonyl (PC, one of the protein oxidation products) and HbA1C increased and ferric reducing antioxidant power (FRAP) decreased in diabetic rats compared to normal rats. Eucalyptus administration for 4 weeks caused a significant decrease in the plasma glucose levels, plasma and liver MDA, PC and HbA1C, also a concomitant increase in the levels of FRAP in diabetic treated rats. In conclusion, the present study showed that eucalyptus posses antioxidant activities. Eucalyptus probably restores antioxidant power, due to the improved hyperglycemia in streptozotocin-induced diabetic rats.  相似文献   
154.
Time-lapse videos of growing biofilms were analyzed using a background subtraction method, which removed camouflaging effects from the heterogeneous field of view to reveal evidence of streamer formation from optically dense biofilm segments. In addition, quantitative measurements of biofilm velocity and optical density, combined with mathematical modeling, demonstrated that streamer formation occurred from mature, high-viscosity biofilms. We propose a streamer formation mechanism by sudden partial detachment, as opposed to continuous elongation as observed in other microfluidic studies. Additionally, streamer formation occurred in straight microchannels, as opposed to serpentine or pseudo-porous channels, as previously reported.  相似文献   
155.
This paper discusses a partnership involving teachers and a teacher educator working together to develop teaching and learning practices in Pakistan. The partnership was established in response to the teachers’ need for support in developing their professional practices within the actual contexts and realities of their schools, after they had attended an in-service training course at a university. Providing case studies, the paper analyses the processes and outcomes of this co-learning partnership. The findings suggest that the collaborative process advances the understanding of teachers’ problems, resolves them on the spot, and provides teachers with the confidence and courage to transcend the constraints of their workplaces while developing professionally.  相似文献   
156.
The present comparative study investigates the perceptions of male and female teachers regarding the relationship between empowerment and job satisfaction. The study aims to look at factors that empower teachers and lead to job satisfaction from teachers’ perspectives. For that purpose, teachers were selected from three educational levels (primary, middle and secondary) in Al-Farwaniya District in the State of Kuwait. A total of 231 teachers from the Al-Farwaniya School District responded to a questionnaire. Both t-test and one-way ANOVA were applied. Data analysis reveals a lack of job empowerment and a high degree of dissatisfaction among teachers. The study concludes with several suggestions including opening up a dialogue with teachers in order to understand their problems and needs and involving them in the process of decision-making and change.  相似文献   
157.
158.
In this study, a 3D passivated-electrode, insulator-based dielectrophoresis microchip (3D πDEP) is presented. This technology combines the benefits of electrode-based DEP, insulator-based DEP, and three dimensional insulating features with the goal of improving trapping efficiency of biological species at low applied signals and fostering wide frequency range operation of the microfluidic device. The 3D πDEP chips were fabricated by making 3D structures in silicon using reactive ion etching. The reusable electrodes are deposited on second glass substrate and then aligned to the microfluidic channel to capacitively couple the electric signal through a 100 μm glass slide. The 3D insulating structures generate high electric field gradients, which ultimately increases the DEP force. To demonstrate the capabilities of 3D πDEP, Staphylococcus aureus was trapped from water samples under varied electrical environments. Trapping efficiencies of 100% were obtained at flow rates as high as 350 μl/h and 70% at flow rates as high as 750 μl/h. Additionally, for live bacteria samples, 100% trapping was demonstrated over a wide frequency range from 50 to 400 kHz with an amplitude applied signal of 200 Vpp. 20% trapping of bacteria was observed at applied voltages as low as 50 Vpp. We demonstrate selective trapping of live and dead bacteria at frequencies ranging from 30 to 60 kHz at 400 Vpp with over 90% of the live bacteria trapped while most of the dead bacteria escape.  相似文献   
159.
Due to the proliferation and abundance of information on the web, ranking algorithms play an important role in web search. Currently, there are some ranking algorithms based on content and connectivity such as BM25 and PageRank. Unfortunately, these algorithms have low precision and are not always satisfying for users. In this paper, we propose an adaptive method, called A3CRank, based on the content, connectivity, and click-through data triple. Our method tries to aggregate ranking algorithms such as BM25, PageRank, and TF-IDF. We have used reinforcement learning to incorporate user behavior and find a measure of user satisfaction for each ranking algorithm. Furthermore, OWA, an aggregation operator is used for merging the results of the various ranking algorithms. A3CRank adapts itself with user needs and makes use of user clicks to aggregate the results of ranking algorithms. A3CRank is designed to overcome some of the shortcomings of existing ranking algorithms by combining them together and producing an overall better ranking criterion. Experimental results indicate that A3CRank outperforms other combinational ranking algorithms such as Ranking SVM in terms of P@n and NDCG metrics. We have used 130 queries on University of California at Berkeley’s web to train and evaluate our method.  相似文献   
160.
The ability to engage and inspire younger generations in novel areas of science is important for bringing new researchers into a burgeoning field, such as lab-on-a-chip. We recently held a lab-on-a-chip workshop for secondary school students, for which we developed a number of hands-on activities that explained various aspects of microfluidic technology, including fabrication (milling and moulding of microfluidic devices, and wax printing of microfluidic paper-based analytical devices, so-called μPADs), flow regimes (gradient formation via diffusive mixing), and applications (tissue analysis and μPADs). Questionnaires completed by the students indicated that they found the workshop both interesting and informative, with all activities proving successful, while providing feedback that could be incorporated into later iterations of the event.  相似文献   
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