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21.
介绍了JSP技术的一些特性和原理。研究了在B/S模式下,网络数据库的三层结构及各层功能,讨论了JSP访问数据库的基本方法,并介绍了利用可重用Java,Bean技术封装数据库操作的思想。  相似文献   
22.
Rapid detection of brain natriuretic peptide (BNP) concentration can be used for the diagnosis of acute heart failure and for the evaluation of the effectiveness of a clinical therapy. We used the systematic evolution of ligands by exponential enrichment method to develop DNA aptamers for BNP whose sequences were determined by cloning method and consensus sequence analysis. A total of eight conserved sequences was identified. By combining the fluorescent-labeled aptamers with fast protein lab-on-chip analysis, we could achieve quantification of BNP concentrations with high speed, sensitivity, and specificity.  相似文献   
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ABSTRACT

Research regarding the effects of high-intensity interval training (HIIT) on executive function has grown exponentially in recent years. However, there has been no comprehensive review of the current state of literature. Therefore, the aim of this systematic review is to summarize previous research regarding the acute and chronic effects of HIIT on executive function across the lifespan and highlight future research directions. The results indicated that acute bouts of HIIT has a positive effect on inhibition in children/adolescents and adults, and further that chronic HIIT benefits inhibition and working memory in children. More research employing chronic interventions, focusing on middle-aged and older adults, and examining the effects on the working memory and cognitive flexibility domains of executive function are needed. Future research should also focus on a) the use of stronger research designs, b) the effects of HIIT dosage/modality, c) consideration of individual differences, d) possible underlying mechanisms, and e) examining the feasibility of translating HIIT to real-word settings.  相似文献   
25.
We have used Brownian dynamics-finite element method (BD-FEM) to guide the optimization of a microfluidic device designed to stretch DNA for gene mapping. The original design was proposed in our previous study [C. C. Hsieh and T. H. Lin, Biomicrofluidics 5(4), 044106 (2011)] for demonstrating a new pre-conditioning strategy to facilitate DNA stretching through a microcontraction using electrophoresis. In this study, we examine the efficiency of the original device for stretching DNA with different sizes ranging from 48.5 kbp (λ-DNA) to 166 kbp (T4-DNA). The efficiency of the device is found to deteriorate with increasing DNA molecular weight. The cause of the efficiency loss is determined by BD-FEM, and a modified design is proposed by drawing an analogy between an electric field and a potential flow. The modified device does not only regain the efficiency for stretching large DNA but also outperforms the original device for stretching small DNA.  相似文献   
26.
This paper describes two studies, one a pilot and the second, an enhanced study, that compare problem-based learning and lecture-based learning in library instruction for first-year engineering students. Two distinct assessment strategies were used to provide empirical evidence that supports the use of problem-based learning as an effective teaching method. Based on the results of the enhanced study, the authors conclude that problem-based learning leads to better outcomes for the learning styles of engineering students.  相似文献   
27.
The Web-at-Risk project is a digital preservation project funded by the Library of Congress as part of the National Digital Information Infrastructure and Preservation Program. The project is developing a Web archiving service to enable curators to build, store, and manage archived collections of Web-published materials captured largely from U.S. federal and state government agency Web sites. In 2005 the project’s 22 curators, as well as librarians and archivists working primarily in academic libraries (n = 43), university researchers (n = 7), and content providers (n = 7) participated in a study to identify their needs in relation to Web archiving. This paper summarizes the issues and challenges these groups face and discusses the need for collaborations among libraries and government entities for preserving Web-published materials.  相似文献   
28.
In order to determine time efficiency between the gel-based microchip (LabChip) and traditional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), glycoproteins and lipopolysaccharides were analyzed in this study. After 90 min of gel electrophoresis, glycoproteins (bovine serum albumin, lysozyme, ovalbumin, and apo-transferrin) and fluorescent lipopolysaccharides (LPS-O and LPS-S) under reducing conditions could be analyzed by SDS-PAGE, and it would take (including imaging and analyzing) more than 3 h. The same sample could also be assayed on a Bioanalyzer in combination with the LabChip, and it would only need 30 min from start to finish. The assay software automatically calculated the size and concentration of each separated peak and displayed the results in real time, thus eliminating time-consuming procedures such as imaging and analyzing. Compared to the traditional reducing SDS-PAGE, LabChip has a faster turnaround time.  相似文献   
29.
The purpose of this study is to examine the moderating role of cognitive load experience between students’ scientific epistemic beliefs and information commitments, which refer to online evaluative standards and online searching strategies. A total of 344 science-related major students participated in this study. Three questionnaires were used to ascertain the students’ scientific epistemic beliefs, information commitments, and cognitive load experience. Structural equation modeling was then used to analyze the moderating effect of cognitive load, with the results revealing its significant moderating effect. The relationships between sophisticated scientific epistemic beliefs and the advanced evaluative standards used by the students were significantly stronger for low than for high cognitive load students. Moreover, considering the searching strategies that the students used, the relationships between sophisticated scientific epistemic beliefs and advanced searching strategies were also stronger for low than for high cognitive load students. However, for the high cognitive load students, only one of the sophisticated scientific epistemic belief dimensions was found to positively associate with advanced evaluative standard dimensions.  相似文献   
30.
Recently, we have reported the experimental results of DNA stretching by flow field in three microchannels (C. H. Lee and C. C. Hsieh, Biomicrofluidics 7(1), 014109 (2013)) designed specifically for the purpose of preconditioning DNA conformation for easier stretching. The experimental results do not only demonstrate the superiority of the new devices but also provides detailed observation of DNA behavior in complex flow field that was not available before. In this study, we use Brownian dynamics-finite element method (BD-FEM) to simulate DNA behavior in these microchannels, and compare the results against the experiments. Although the hydrodynamic interaction (HI) between DNA segments and between DNA and the device boundaries was not included in the simulations, the simulation results are in fairly good agreement with the experimental data from either the aspect of the single molecule behavior or from the aspect of ensemble averaged properties. The discrepancy between the simulation and the experimental results can be explained by the neglect of HI effect in the simulations. Considering the huge savings on the computational cost from neglecting HI, we conclude that BD-FEM can be used as an efficient and economic designing tool for developing new microfluidic device for DNA manipulation.  相似文献   
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