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981.
The purpose of this paper is to compute the Hankel transform Fn(y) of order n of a function f(x) and its inverse transform using rationalized Haar wavelets. The integrand is replaced by its wavelet decomposition. Thus representing Fn(y) as a Fourier-Bessel series with coefficients depending strongly on the local behavior of the function , thereby getting an efficient algorithm for their numerical evaluation. Numerical evaluations of test functions with known analytical Hankel transforms illustrate the proposed algorithm. 相似文献
982.
The increasing number of interactions between Taiwan and the Mainland may bring in both opportunities and competitions among the companies in the region. Companies are forced to continuously change and develop to advance and to sustain in the competitive environment. It also holds true for the companies in the even more competitive high-tech industries. It is therefore of a value to study what challenges the high-tech firms are facing, how these challenges impact on their performance and how these firms are dealing with issues. Among the multiple challenges, supply chain operation has been a critical issue concerning the high-tech manufacturers.The purpose of this study is to investigate the relationships between the various supply chain operation determinants (relationships with business partners, internal operation) and the impacts of relationships with supply chain partners on the internal operation and the collective efficacy relating to the scheduling issues in high-tech manufacturing firms in Taiwan. A research framework linking internal operation and relationships with supply chain partners (supplier and customer) and individuals (perceived collective efficacy) is applied. 相似文献
983.
Gergely Simon Caroline Busch Marco A. B. Andrade Julien Reboud Jonathan M. Cooper Marc P. Y. Desmulliez Mathis O. Riehle Anne L. Bernassau 《Biomicrofluidics》2021,15(1)
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes. 相似文献
984.
Dong-Dong Wu Cui-Ping Yang Ming-Shan Wang Kun-Zhe Dong Da-Wei Yan Zi-Qian Hao Song-Qing Fan Shu-Zhou Chu Qiu-Shuo Shen Li-Ping Jiang Yan Li Lin Zeng He-Qun Liu Hai-Bing Xie Yun-Fei Ma Xiao-Yan Kong Shu-Li Yang Xin-Xing Dong Ali Esmailizadeh David M Irwin Xiao Xiao Ming Li Yang Dong Wen Wang Peng Shi Hai-Peng Li Yue-Hui Ma Xiao Gou Yong-Bin Chen Ya-Ping Zhang 《国家科学评论(英文版)》2020,7(6):952
Abundant and diverse domestic mammals living on the Tibetan Plateau provide useful materials for investigating adaptive evolution and genetic convergence. Here, we used 327 genomes from horses, sheep, goats, cattle, pigs and dogs living at both high and low altitudes, including 73 genomes generated for this study, to disentangle the genetic mechanisms underlying local adaptation of domestic mammals. Although molecular convergence is comparatively rare at the DNA sequence level, we found convergent signature of positive selection at the gene level, particularly the EPAS1 gene in these Tibetan domestic mammals. We also reported a potential function in response to hypoxia for the gene C10orf67, which underwent positive selection in three of the domestic mammals. Our data provide an insight into adaptive evolution of high-altitude domestic mammals, and should facilitate the search for additional novel genes involved in the hypoxia response pathway. 相似文献
985.
Ivan Bradaric Athina P. Petropulu Konstantinos I. Diamantaras 《Journal of The Franklin Institute》2002,339(2):161-187
Higher-order statistics (HOS) are well known for their robustness to additive Gaussian noise and ability to preserve phase. HOS estimates, on the other hand, have been criticized for high complexity and the need for long data in order to maintain small variance. Since rank reduction offers a general principle for reduction of estimator variance and complexity, we consider the problem of designing low-rank estimators for HOS. We propose three methods for choosing the transformation matrix that reduces the mean-square error (MSE) associated with the low-rank HOS estimates. We also demonstrate the advantages of using low-rank third-order moment estimates for blind system estimation. Results indicate that the full rank MSE corresponding to some data length N can be attained by a low-rank estimator corresponding to a length significantly smaller than N. 相似文献
986.
Size-dependent trajectories of DNA macromolecules due to insulative dielectrophoresis in submicrometer-deep fluidic channels 总被引:1,自引:0,他引:1
Gea O. F. Parikesit Anton P. Markesteijn Oana M. Piciu Andre Bossche Jerry Westerweel Ian T. Young Yuval Garini 《Biomicrofluidics》2008,2(2)
In this paper, we demonstrate for the first time that insulative dielectrophoresis can induce size-dependent trajectories of DNA macromolecules. We experimentally use λ (48.5 kbp) and T4GT7 (165.6 kbp) DNA molecules flowing continuously around a sharp corner inside fluidic channels with a depth of 0.4 μm. Numerical simulation of the electrokinetic force distribution inside the channels is in qualitative agreement with our experimentally observed trajectories. We discuss a possible physical mechanism for the DNA polarization and dielectrophoresis inside confining channels, based on the observed dielectrophoresis responses due to different DNA sizes and various electric fields applied between the inlet and the outlet. The proposed physical mechanism indicates that further extensive investigations, both theoretically and experimentally, would be very useful to better elucidate the forces involved at DNA dielectrophoresis. When applied for size-based sorting of DNA molecules, our sorting method offers two major advantages compared to earlier attempts with insulative dielectrophoresis: Its continuous operation allows for high-throughput analysis, and it only requires electric field strengths as low as ∼10 V∕cm. 相似文献
987.
Many Web sites have begun allowing users to submit items to a collection and tag them with keywords. The folksonomies built from these tags are an interesting topic that has seen little empirical research. This study compared the search information retrieval (IR) performance of folksonomies from social bookmarking Web sites against search engines and subject directories. Thirty-four participants created 103 queries for various information needs. Results from each IR system were collected and participants judged relevance. Folksonomy search results overlapped with those from the other systems, and documents found by both search engines and folksonomies were significantly more likely to be judged relevant than those returned by any single IR system type. The search engines in the study had the highest precision and recall, but the folksonomies fared surprisingly well. Del.icio.us was statistically indistinguishable from the directories in many cases. Overall the directories were more precise than the folksonomies but they had similar recall scores. Better query handling may enhance folksonomy IR performance further. The folksonomies studied were promising, and may be able to improve Web search performance. 相似文献
988.
Benedicta D’Souza Vivian D’Souza S. Sowmya G. Seema C. N. Hemalatha M. Anu G. Sajana 《Indian journal of clinical biochemistry : IJCB》2008,23(3):218-222
The study was conducted to find out the extent of lipid peroxidation and antioxidant status in ischemic stroke patients (ISPs)
with and without diabetes. Malondialdehyde (MDA) was studied as a marker of lipid peroxidation. Glutathione (GSH), uric acid
and ceruloplasmin were estimated to study the antioxidant potential of ISPs. Significantly higher levels of MDA were found
in both the groups of ISPs and the increase in MDA was more in ISPs without diabetes. GSH levels were decreased significantly
in both the groups of ISPs and maximum decline was found in ISPs with diabetes. Uric acid levels were significantly increased
in both the groups of ISPs. Ceruloplasmin levels were increased significantly in ISPs without diabetes, whereas its levels
were slightly decreased in ISPs with diabetes. A negative correlation was found between MDA and the antioxidants GSH, uric
acid and ceruloplasmin in ISPs with diabetes. This study suggests that there is an association between ischemic stroke and
increased oxidative stress and the antioxidant potential is impaired in both the groups of ISPs with and without diabetes. 相似文献
989.
This paper constitutes an attempt to explore trends, issues and challenges that emerge when three different cohorts of pre-service teachers debate contemporary issues in science education at the University of Botswana. Apart from the author's experience of teaching the course, the impetus for this study also comes from a growing interest in the contemporary literature in the need for teachers who, in the context of globalization and knowledge economy, are ‘self-reforming’ through continually addressing the key issues of their profession. Unfortunately, the current situation is such that this burden of interrogation falls heaviest on teachers, despite their lack of skills in undertaking the task. 相似文献
990.
Melissa Gilliam Patrick Jagoda Erin Jaworski Luciana E. Hebert Phoebe Lyman M. Claire Wilson 《Sex education》2016,16(4):391-404
This paper describes the development and evaluation of an interactive, narrative-based, multimedia game to promote learning and communication about sexual violence and health topics. High school-aged participants created the game concept in a three-week workshop, after which assets were assembled and refined by a university-based game design lab. The outcome, Lucidity, was a multimedia game with a nonlinear narrative that led to two different outcomes based on player decisions. The narrative followed the life of one character, an African American woman named Zaria who remembers and grapples with a sexual assault from her past. The player discovers parts of the story by reading comics, watching videos, navigating interactive websites and playing short videogames. The final evaluation consisted of gameplay, a post-game focus group and follow-up interviews. Twenty-four young people participated in three focus group discussions (n = 9, n = 5, n = 10); 23 participated in the follow-up interviews. Salient themes identified in the focus group discussions included: overall approval of the game, the acquisition of new knowledge and minimal past exposure to conversations or education about sexual violence. At follow-up, almost all (n = 22) had initiated a conversation about sexual violence with a parent, peer and/or teacher. Lucidity succeeded in engaging young people and facilitating communication with adults and peers regarding sexual violence and other sexual health topics. Ultimately, a game-based intervention such as this represents a feasible approach for introducing issues of sexual violence, with potential for future implementation in educational settings. 相似文献