排序方式： 共有57条查询结果，搜索用时 343 毫秒
41.
Montazery-Kordy H Miran-Baygi MH Moradi MH 《Journal of Zhejiang University. Science. B》2008,9(11):863-870
Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most infor-mative proteins that could be used to fred the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality re-duction procedure, the hard threshoiding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power. 相似文献
42.
Thin-walled spread foundations are used in coastal projects where the soil strength is relatively low. Developing a predictive model of bearing capacity for this kind of foundation is of interest due to the fact that the famous bearing capacity equations are proposed for conventional footings. Many studies underlined the applicability of artificial neural networks (ANNs) in predicting the bearing capacity of foundations. However, the majority of these models are built using conventional ANNs, which suffer from slow rate of learning as well as getting trapped in local minima. Moreover, they are mainly developed for conventional footings. The prime objective of this study is to propose an improved ANN-based predictive model of bearing capacity for thin-walled shallow foundations. In this regard, a relatively large dataset comprising 145 recorded cases of related footing load tests was compiled from the literature. The dataset includes bearing capacity (Qu), friction angle, unit weight of sand, footing width, and thin-wall length to footing width ratio (Lw/B). Apart from Qu, other parameters were set as model inputs. To enhance the diversity of the data, four more related laboratory footing load tests were conducted on the Johor Bahru sand, and results were added to the dataset. Experimental findings suggest an almost 0.5 times increase in the bearing capacity in loose and dense sands when Lw/B is increased from 0.5 to 1.12. Overall, findings show the feasibility of the ANN-based predictive model improved with particle swarm optimization (PSO). The correlation coefficient was 0.98 for testing data, suggesting that the model serves as a reliable tool in predicting the bearing capacity. 相似文献
43.
INTRODUCTION A number of experimental fatigue studies were conducted on plain concrete as well as on steel fibre reinforced concrete (SFRC) beams of different sizes under different loading conditions. Murdock and Kesler (1958) investigated the effect of stress ratio on the fatigue strength of plain concrete. Batson et al.(1972) reported fatigue strength of 74% and 83% of the first crack static flexural strength at 2 million cycles of complete reversed and not-reversed loads respectively… 相似文献
44.
The hypothesis that proportionately more boys than girls experience reading failure was tested on a sample of 708 children using both test-identified and teacher-identified criteria. Test-identified reading failure was defined by low scores on standardized reading achievement tests given at the end of first and third grade. For Severely Reading Disabled (total reading score at the 10th percentile or lower), the ratio of boys to girls was 1.4:1 at first grade and 1.3:1 at third. At both grades equal proportions of boys and girls were represented in the Reading Disabled category (total reading score between the 11th and 30th percentile). Teacher-identified reading failure criteria consisted of enrollment in LD and Chapter One (remedial reading) programs at first and third grades. Teacher-identified ratios of boys to girls in LD were 2:1 at both first and third grade, exceeding the test-identified ratios, while identification for Chapter One services did not show a gender difference. 相似文献
45.
ABSTRACTMultimodality has been a growing research interest in the field of applied linguistics. With the actor-network theory as an analytic framework, the purpose of the present study was to explore how university students of Teaching English as a Foreign Language (TEFL) take advantage of both material and non-material semiotic resources while being involved in the process of developing classroom activities. Furthermore, the semiotic resources of these students including their language, gaze, and gesture were analyzed using systemic functional multimodal discourse analysis (SF-MDA). To do this, using an ethnomethodology, we videotaped the interaction of a group of 6 TEFL students developing materials, for the improvement of learners’ intercultural competence, on the topic of food. The findings indicated that the participants developed these materials as they interacted with each other, as human semiotic resources, as well as their digital tools, as non-human resources. In addition, while mainly expressing their mental processes, they also conveyed positive attitudes and built negotiation expanding space using their gesture with both fast and slow graduation. Their gaze was also engaged, directed at both the group members and objects developing the classroom activities. 相似文献
46.
Developing entrepreneurial graduates is essential to the future of higher education and supply of quality human resources in developing countries. To address this issue in the agriculture sector, which is dominant in economic terms in most developing countries, an exploratory combined qualitative and quantitative research was conducted to understand entrepreneurial learning of agricultural graduate entrepreneurs. For the phenomenological study, 14 agricultural graduate entrepreneurs were purposely selected, and for the quantitative study, 92 entrepreneurs were selected through simple random sampling method. The phenomenological study revealed 12 themes on how graduates experienced entrepreneurial learning. Our study finds support for “experiential learning,” “learning by doing,” and “social learning” theories. Nine themes including previous business experience, risk-taking propensity, entrepreneurial persistence, use of various information sources, tendency to be self-employed, concerns about job or career, interest in practical courses and activities, passion for agriculture, and thinking outside the box are internal to the entrepreneur and could be seen as learner identity. The theme of “support from family and friends” could be seen as a significant external influence. The survey showed that entrepreneurial learning themes were generalizable to the studied population. Although different students can take different learning paths to become the best they can be, our findings suggest that the overall student learning experience can be designed to ensure that graduates are more likely to become entrepreneurs. 相似文献
47.
Multipotentiality is widely cited as a characteristic of the most gifted individuals. It refers to their ability and interest to pursue various activities and goals especially as related to leisure and career choice. Multipotentiality appears beneficial, but can also lead to problems in career decision-making. Evidence for such problems, however, is contradictory and often anecdotal. This research, a follow-up study to Rysiew, Shore and Carson (1984), through the examination of longitudinal empirical data, sought to ascertain the outcomes of multipotentiality and to examine its effects on career decision-making. The sample comprised 180 participants (110 males and 70 females), which is 73% of 1984 sample. The average verbal IQ (Otis & Lennon, 1969) was 124.5. Results show that multipotentiality seemed not problematic, and evidence for career indecision was lacking. As for moderating variables, participants' considered experiences to be beneficial. 相似文献
48.
DEHGHANI Mohammad Hadi MAHVI Amir Hossein NAJAFPOOR Ali Asghar AZAM Kamal 《浙江大学学报(A卷英文版)》2007,8(9):1462-1468
The effectiveness of using acoustical (sonochemical) reactor for degradation of linear alkylbenzen sulfonate (LAS) from aqueous solution was investigated. LASs are anionic surfactants,found in relatively high amounts in domestic and industrial wastewaters. In this study,experiments on LAS solution were performed using methylene blue active substances (MBAS) method. The effectiveness of acoustical processor reactor for LAS degradation is evaluated with emphasis on the effect of treatment time and initial LAS concentration. Experiments were performed at initial concentrations of 0.2,0.5,0.8 and 1.0 mg/L,acoustic fre-quency of 130 kHz,applied power of 500 W and temperature of 18 °C～20 °C. At the conditions involved,LAS degradation was found to increase with increasing sonochemical time. In addition,as the concentration increased,the LAS degradation rate de-creased in the acoustical processor reactor. 相似文献
49.
A wide range of diseases and conditions are monitored or diagnosed from blood plasma, but the ability to analyze a whole blood sample with the requirements for a point-of-care device, such as robustness, user-friendliness, and simple handling, remains unmet. Microfluidics technology offers the possibility not only to work fresh thumb-pricked whole blood but also to maximize the amount of the obtained plasma from the initial sample and therefore the possibility to implement multiple tests in a single cartridge. The microfluidic design presented in this paper is a combination of cross-flow filtration with a reversible electroosmotic flow that prevents clogging at the filter entrance and maximizes the amount of separated plasma. The main advantage of this design is its efficiency, since from a small amount of sample (a single droplet ～ 10 μl) almost 10% of this (approx 1 μl) is extracted and collected with high purity (more than 99%) in a reasonable time (5–8 min). To validate the quality and quantity of the separated plasma and to show its potential as a clinical tool, the microfluidic chip has been combined with lateral flow immunochromatography technology to perform a qualitative detection of the thyroid-stimulating hormone and a blood panel for measuring cardiac Troponin and Creatine Kinase MB. The results from the microfluidic system are comparable to previous commercial lateral flow assays that required more sample for implementing fewer tests. 相似文献
50.