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51.
This investigation examined the oxidative stress (F2-Isoprostane; F2-IsoP) and inflammatory (interleukin-6; IL-6) responses to repeat-sprint training in hypoxia (RSH). Ten trained male team sport athletes performed 3(sets)*9(repetitions)*5?s cycling sprints in simulated altitude (3000?m) and sea-level conditions. Mean and peak sprint power output (MPO and PPO) were recorded, and blood samples were collected pre-exercise, and again at 8 and 60?min post-exercise. Both MPO and PPO were significantly reduced in hypoxia (compared to sea-level) in the second (MPO: 855?±?89 vs. 739?±?95?W, p?=?.006; PPO: 1024?±?114 vs. 895?±?112?W, p?=?.010) and third (MPO: 819?±?105 vs. 686?±?83?W, p?=?.008; PPO: 985?±?125 vs. 834?±?99?W, p?=?.008) sets, respectively. IL-6 was significantly increased from pre- to 1?h post-exercise in both hypoxia (0.7?±?0.2 vs. 2.4?±?1.4?pg/mL, p?=?.004) and sea-level conditions (0.7?±?0.2 vs. 1.6?±?0.3?pg/mL, p?d?=?0.80) suggesting higher IL-6 levels of post-hypoxia. F2-IsoP was significantly lower 1?h post-exercise in both the hypoxic (p?=?.005) and sea-level (p?=?.002) conditions, with no differences between trials. While hypoxia can impact on exercise intensity and may result in greater post-exercise inflammation, it appears to have little effect on oxidative stress. These results indicate that team sport organisations with ready access to hypoxic training facilities could confidently administer RSH without significantly increasing the post-exercise inflammatory or oxidative stress response.  相似文献   
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The academic award restructuring of 1991 established a trial period for academic staff appraisal for the purposes of staff development. The trend in Australia towards more formal performance management for academics has occurred during a period of substantial change to the structure of higher education and institutional management, and brought debate on whether appraisal, for either summative purposes (where performance assessment is for remuneration or promotion purposes) or formative purposes (where the emphasis is on planning personal development), is appropriate for academic staff. Arguments have been put forward for the benefits of appraisal processes with primarily developmental intent. Thus far there have been reports of the characteristics and processes of appraisal schemes, but less data on outcomes; in particular, little evidence to indicate the extent to which schemes lead to worthwhile staff development. This paper reports selected findings of a study of the evolving appraisal scheme of The University of Melbourne. The study was conducted after the scheme's second year of operation by the Centre for the Study of Higher Education which played an advisory role in an internal review of the scheme. The findings reveal some uncertainty among staff about the intentions of the scheme, and tensions between summative and formative purposes, perhaps not surprising given the contentious issue which staff appraisal has been in higher education. Nevertheless, positive outcomes were identified, but possibly too few to claim that the scheme was fully achieving a developmental objective. These findings raise questions about the effectiveness of academic staff appraisal nationally and suggest that it is time to reconsider the policy linkage between appraisal and staff development.  相似文献   
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This paper addresses a dynamic portfolio investment problem. It discusses how we can dynamically choose candidate assets, achieve the possible maximum revenue and reduce the risk to the minimum level. The paper generalizes Markowitz's portfolio selection theory and Sharpe's rule for investment decision. An analytical solution is presented to show how an institutional or individual investor can combine Markowitz's portfolio selection theory, generalized Sharpe's rule and Value-at-Risk(VaR) to find candidate assets and optimal level of position sizes for investment (dis-investment). The result shows that the generalized Markowitz's portfolio selection theory and generalized Sharpe's rule improve decision making for investment.  相似文献   
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Purpose: This paper reports the results of survey research conducted with tribal producers between 2011 and 2012 on 19 of the largest American Indian reservations in Idaho, Nevada, North Dakota, Oregon, South Dakota, and Washington. The purpose of the research was to identify potential barriers to sustainable agriculture on reservation lands. This article reports the results of this research in an effort to promote Extension professionals' understanding of these barriers, which may help to improve outreach programs on American Indian reservations. Understanding the obstacles to sustaining agriculture that American Indian tribes face may inform international agricultural outreach efforts to increase food security targeting indigenous and tribal peoples worldwide.

Design/Methodology/Approach: American Indian agricultural producers comprised the study group. Study objectives included: (1) identify agricultural and natural resource issues of greatest concern to a self-selected sample of tribal agricultural producers on reservation lands; (2) evaluate access to Extension and other US Department of Agriculture outreach and assistance programs; and (3) evaluate the quality of these programs in terms of their relativity to tribal needs.

Findings: Study results indicate that tribal agricultural producers surveyed ranked 29 of 39 agricultural and natural resource issues as a concern. Similarly, they rated access to and quality of outreach programs as fair. Further, tribal producers operating on reservation trust land rated issues more severely than did tribal producers operating on fee simple lands.

Practical Implications: Results of this research will help Extension and other outreach professionals to understand the barriers indigenous and tribal peoples face in sustaining agricultural operations, particularly tribal groups living on federally reserved trust lands, such as American Indians. An increased understanding can inform agricultural policy-makers and outreach professionals in improving programs designed to increase agricultural sustainability, improve food security, enhance economic well-being and improve quality of life of indigenous and tribal peoples worldwide.

Originality/Value: This research provides important information to agricultural policy-makers and Extension professionals striving to sustain agricultural productivity and enhance food security with indigenous and tribal peoples.  相似文献   

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Increasingly, online learning is perceived as an effective method of instruction. Much recent educational research has focused on examining the purposes and situations for which online education is best suited. In this paper, students enrolled in two online courses are compared with their peers enrolled in equivalent classroom‐based courses to investigate aspects of the relationship between learning style and mode of delivery. Student satisfaction measures are taken from participants in both modes of delivery and compared with student learning style. Feedback from the ‘Reflector’ learning style demonstrates higher satisfaction levels with the online mode of delivery compared with their matched counterparts following equivalent classroom‐based courses. Therefore, whilst ‘Reflectors’ might be regarded as Introverts in the traditional classroom setting, the additional time for reflection offered by online delivery makes this group more likely to contribute to online discussion, report higher satisfaction levels and generally behave more like online Extraverts.  相似文献   
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There are many subtle but extremely important differences between grouping students and tracking students for purposes of designing appropriate instructional interventions. Unfortunately, in many inner-city urban settings, the policy of grouping students eventually becomes a policy ofde facto tracking of students. While grouping students seems to be an educationally justifiable policy in many school situations, tracking students raises serious concerns with regard to its educational value, social desirability, and complicity with the legal notions of due process and equal protection. This study examines the use of a specific form ofshort-term grouping of students that is based on an information-referenced criterion for selection. Using a large sample of ninth- and eleventh-grade students, an information-referenced grouping procedure was designed for the areas of language arts and mathematics. The study finds that grouping selections, using an information-referenced criterion, are strongly associated with teachers perceptions of these students' actual educational and information needs. In addition, the information-referenced grouping design provides important specific educational feedback to both students and teachers to help low-attaining students move to mainstream classes. Finally, many of the due process concerns raised by educational researchers with regard to abuses and shortcomings of presently used ability or standardized test-driven grouping efforts are addressed.  相似文献   
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Recent economic pressures have demanded higher education institutions respond with strong, authentic brand promises. This mixed method multi-case study explored the authenticity of common brand promises at three Universities in Canada through Twitter and Facebook postings from February to April 2016 using a cloud-based text and network analytic tool. Our study revealed the content shared on social media channels, while largely trustworthy, was fraught with shades of gray and revealed that sometimes brand promises were used against the university when they appeared disingenuous or threatened institutional norms around equity and social justice. Further, social media strategies are still largely limited to push notification suggesting universities are missing opportunities to strengthen their brand and counter negative messaging. For marketing managers it reinforces investments should be directed toward creating engaging and authentic content that can be expressed through multiple touch-points including social media and this can be monitored through low-cost analytic tools.  相似文献   
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