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951.
Janice W. Y. Wong Melissa O’Donnell Donna Bayliss Janet Fletcher Rebecca Glauert 《Educational Research for Policy and Practice》2017,16(2):109-127
Policies aiming to improve educational outcomes are typically based on academic testing data. However, such data only reflect the performance of students who completed the tests. It is possible that students who were absent have shared characteristics. The proportion of students absent out of all eligible school students and whether they have shared characteristics has not been investigated, as this is only possible through the use of linked administrative data. Participants were born in Western Australia in 1994 and 1995, and their birth records were linked to participation status in the Year 9 academic tests to determine the proportion of students who were absent. Logistic regression was conducted to investigate characteristics which predicted absence on test day. A proportion of non-Aboriginal (3.2 %) and Aboriginal students (21.9 %) were absent on test day. Risk factors which predicted the absence included contact with Child Protection and Family Services, history of maternal mental health problems, and fathers aged below 20 years at the time of their child’s birth. A significant proportion of students was absent and therefore not represented in academic achievement information. These students were more likely to have experienced adverse events and therefore are not randomly absent. As these data are typically used to inform policies which aim to improve educational outcomes, they may lack the necessary information to adequately address the complex needs of students who are absent on test day. However, findings suggest that service providers, as well as schools may play an important role in encouraging participation in school. 相似文献
952.
Organizational culture has been shown to influence the success of knowledge management practices. Hofstede's theory specifies that organizational culture is not independent of national culture. A case study of an international subsidiary was conducted to explore the extent to which knowledge sharing is dependent on national culture. Results indicate that language differences can create knowledge blocks, and cross-cultural differences can explain the direction of knowledge flows. 相似文献
953.
This paper is devoted to the identification of analytic signals and to find a solution to the following problem. Given a realization of an analytic signal, it is necessary to find the analytic function by which the signal is described. The proposed approach to this problem is based on relatively simple relationships existing between many analytic signals and their respective derivatives. These relationships are closely related to the properties of the dynamic systems which generate the signals under investigation. Simple identification procedures are described and tested by means of computer simulation. 相似文献
954.
Despite being a rather recalcitrant tool, the "Pap smear" is today the major cancer screening technology in the world. This paper examines how and why hetrogeneous actors chose to advocate the Pap smear as a screen for cervical cancer in the late 1940's, and to tinker both in and far beyond the diagnostic laboratory for over 50 years to make the Pap smear "fit" as a screening and clinical technology. Tinkerings included gendering the division of labour, attempting to automate reading of smears, juggling costs, exploring alternative screening technologies, pushing for regulation of laboratories, and settling for locally-negotiated orders of clinical accuracy instead of global standardization, still elusive today. 相似文献
955.
Munzir M. E. Ahmed J. A. S. Al-Obosi H. M. Osman M. E. Shayoub 《Indian journal of clinical biochemistry : IJCB》2016,31(2):162-170
Acetaminophen (APAP) a commonly used drug for decrease the fever and pain but is capable to induced hepatotoxicity at over dose. This study was carried out to investigate the effect of APAP on the expression of anti-apoptotic and antioxidative defense genes, and whether aldose reductase over-expressing plasmid capable to protect against APAP-induced oxidative stress and cell death. APAP treatment induced oxidative stress and hepatotoxicity, and significantly increased aldose reductase mRNA and protein expression in mouse hepatocyte (AML-12). Unexpectedly, AML-12 cells over-expressing aldose reductase augmented APAP-induced reduction in cell viability, reactive oxygen species (ROS) production, glutathione (GSH) depletion and glutathione S-transferase A2 expression. Moreover, over-expression of aldose reductase potentiated APAP induced reduction on proliferating cell nuclear antigen, B cell lymphoma-extra large (bcl-xL), catalase, glutathione peroxidase-1 (GPx-1) and abolished APAP-induced B-cell lymphoma 2 (bcl-2) inductions. Further, over-expression of aldose reductase significantly abolished AMP activated protein kinase (AMPK) activity in APAP-treated cells and induced p53 expression. This results demonstrate that APAP induced toxicity in AML-12, increased aldose reductase expression, and over-expression of aldose reductase render this cell more susceptible to APAP induced oxidative stress and cell death, this probably due to inhibition AMPK or bcl-2 activity, or may due to competition between aldose reductase and glutathione reductase for NADPH. 相似文献
956.
Globalization has contributed to the dismantling of national boundaries, which have enabled firms to compete and conduct business on a wider scale [Held, D., McGrew, A., Goldblatt, D., & Perraton, J. (1999). Global transformations. Politics, economics and culture. Cambridge: Polity Press]. Firms can move freely between different markets using Internet-based technology. While access to such markets can provide firms with greater choice of suppliers and cost efficiencies, they need to be aware of challenges that can influence their business performance. With this in mind, we examine how these factors influenced Alcoa Alumina's drive to a global procurement platform through a global marketplace. The staged adoption process experienced at Alcoa Alumina offers a learning opportunity for other firms considering the transition to global marketplace. 相似文献
957.
Simple as the outflow clock principle may seem for the measurement of time, its translation into an accurate clock raises formidable technical and conceptual problems. An attempt is made here to reconstruct the Egyptians' consciousness of these problems, and the success of their solutions. 相似文献
958.
E. Burton Swanson 《The Information Society》2020,36(2):109-123
AbstractOver some seven decades, a rather mundane transition that in its thoroughness and consequences has gone largely unacknowledged, has taken place, namely the revolution in modern information systems (IS) that guide organizations in their actions. Today, it is fair to say that IS have come to rule the world. They do this literally, by the rules they embody, which dictate how much of everyday life, as it relates to individuals and organizations and the transactions they engage in, takes place around the globe. In essence, IS have become important social and economic infrastructure. Seeking an understanding of how this has come about, I review historical developments in IS, focusing in particular on accounting systems, enterprise systems, retail automation, and electronic commerce. I argue that it is transactions and their facilitation that lie at the heart of IS and its development as a field of practice. I reflect on why this has gone mostly overlooked as such. I consider where we have now arrived with transaction facilitation as infrastructure and its importance in the light of current issues. I suggest how future studies might contribute to our learning more about where we should want to be with our transaction facilitation infrastructure. 相似文献
959.
The enzyme theory and the origin of biochemistry 总被引:3,自引:0,他引:3
960.
A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown. 相似文献