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951.
Today's doctoral programs continue to prepare students for a traditional academic career path despite the inadequate supply of research-focused faculty positions. We advocate for a broader doctoral curriculum that prepares trainees for a wide range of science-related career paths. In support of this argument, we describe data from our survey of doctoral students in the basic biomedical sciences at University of California, San Francisco (UCSF). Midway through graduate training, UCSF students are already considering a broad range of career options, with one-third intending to pursue a non-research career path. To better support this branching career pipeline, we recommend that national standards for training and mentoring include emphasis on career planning and professional skills development to ensure the success of PhD-level scientists as they contribute to a broadly defined global scientific enterprise. 相似文献
952.
There is a worldwide shortage of organs for transplantation. It has been shown that the attitude of healthcare professionals can improve the rates of organ donation, and that educational programs aimed at improving both attitudes and knowledge base of professionals can have positive outcomes. Although there has been research carried out on this topic, there has been none in Ireland. Anatomy dissection can be a stressor to medical students-we investigate the attitudes of Irish students to organ donation and how they change with exposure to anatomy dissection. A questionnaire was administered to first year students in the School of Medicine in University College Dublin, Ireland, three times over a nine-week period at the commencement of classes in an academic year. The attitudes of the students were positive throughout regarding organ donation by a stranger, a family member, or themselves. There was, however, a significant decrease in support for the donation of a family member's organs in a minority of students. Irish students' attitudes to postmortem organ donation are positive and are not changed by exposure to the dissecting room. There is support for the donation of organs, and willingness among students to donate their own organs and support donation by family members. 相似文献
953.
Harnessing technology to improve formative assessment of student conceptions in STEM: forging a national network 总被引:2,自引:0,他引:2
Haudek KC Kaplan JJ Knight J Long T Merrill J Munn A Nehm R Smith M Urban-Lurain M 《CBE life sciences education》2011,10(2):149-155
Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students' thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation-funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community. 相似文献
954.
Dacai Liu Zhi Liu C.L. Philip Chen Yun Zhang 《Journal of The Franklin Institute》2021,358(3):1782-1811
The existing studies on prescribed-time control cannot directly deal with nonlinear functions which don’t satisfy Lipschitz growth conditions. No results are available for prescribed-time containment control of pure-feedback UNMASs with prescribed performance. Therefore, completely unknown nonlinear function, prescribed-time tracking of system states and prescribed performance of containment errors are simultaneously considered in this paper. Fuzzy logic systems are utilized to approximate completely unknown nonlinear function. Prescribed-performance function is introduced and further incorporated into a novel speed function. Combining the proposed speed function and barrier Lyapunov function, this article presents a novel adaptive fuzzy prescribed-time containment control method which can guarantee, under prescribed performance, all followers converge to a convex formed by dynamic leaders in a prescribed time. Moreover, all tracking errors converge to predefined regions in a prescribed time. The effectiveness of the proposed prescribed-time containment control method are confirmed by strict proof and simulation. 相似文献
955.
Purpose: The purposes of this clinical perspective paper are (1) to expand physical therapists’ awareness to the topic of air quality as a health priority when providing professional services; and (2) to provide templates for screening the indoor clinical environments and patient profiles to avert respiratory exacerbations, especially in persons with asthma. Summary of Key Points: The location where a physical therapist practices determines the air quality indices to which a person is exposed. Poor indoor air quality can expose a person to even greater compromise of respiration (ie, Sick Building Syndrome) than outdoor air quality secondary to an array of factors like building materials, the ventilation exchange rate of an enclosed space, chemicals used in cleaning, and humidity. Statement of Conclusions: Extrinsic (ie, environmental) and intrinsic (eg, pre-disposition to airway hypersensitivity) factors must be accounted for by physical therapists to safeguard their patients and themselves from experiencing respiratory compromise and/or distress as a result of a treatment session or their place of employment. Recommendations: Efforts to screen indoor environments for potential triggers and patient risk profiles for abnormal airway reactivity should routinely be undertaken. Individualized Action Plans should be prospectively prepared and readied for implementation when warranted.Key Words: asthma, Sick Building Syndrome, indoor air quality, respiratory impairment 相似文献
956.
Kevin King N. C. Perkins Hugh Churchill Ryan McGinnis Ryan Doss Ron Hickland 《Sports Engineering》2011,13(2):95-104
This paper presents a novel sensor technology to deduce the dynamics of a bowling ball. The sensor, a miniature wireless inertial
measurement unit (IMU), incorporates MEMS accelerometers and angular rate gyros, a microcontroller, a low power RF transceiver,
and a rechargeable battery. When embedded in a bowling ball, the IMU transmits the acceleration and angular velocity data
that define the dynamics of the ball starting with the bowler’s delivery and its motion in the lane. Example results from
professional bowlers illustrate how this technology can be used to assess bowler skill and ball performance. For instance,
the IMU accurately measures the spin dynamics of the ball which are crucial to develop the ball “hook.” An analysis of ball
dynamics in the lane is distilled to a measurable “hook potential” metric for further assessing bowler skill. Finally, the
sensor presented herein is believed to be the world’s smallest, wireless IMU. This highly miniaturized and wireless design
will enable parallel training systems for many sports, including basketball, baseball, crew, cricket, golf, fly fishing, soccer,
softball, tennis, rowing, among others. 相似文献
957.
关联规则挖掘是解决电子商务推荐问题的重要方法之一.针对传统关联规则挖掘算法在解决移动电子商务环境个性化推荐问题时反复扫描数据库,频繁项挖掘效率低,关联规则挖掘准确率低以及规则大量冗余等不足,提出一个基于事务矩阵和用户兴趣度的关联规则挖掘算法(Matrix-and-Interestingness-based Association Rules Mining,MIbARM).该算法仅需扫描一次数据库,并在挖掘过程中不断缩小算法搜索空间以避免生成冗余候选项,同时避免了冗余规则挖掘,从而提高了挖掘效率.最后,在四组人工数据和160种参数组合的数值实验环境下,引入Apriori、CBAR 及BitTableFI算法对MIbARM进行对比验证.结果表明,在不减少有趣规则的前提下,MIbARM不但可有效避免冗余候选项集的产生,而且大幅减少了冗余规则数量,极大提高了算法的搜索效率,同时提升了个性化推荐的质量,更适用于移动电子商务环境下的个性化推荐问题. 相似文献
958.
Madhusudhana Rao A Anand U Anand CV 《Indian journal of clinical biochemistry : IJCB》2011,26(1):28-31
Numerous lines of evidence implicate a role of myeloperoxidase (MPO) in the pathogenesis of cardiovascular disease (CVD).
It is a well accepted fact that patients with chronic kidney disease (CKD) are at an increased risk for CVD. MPO is a pro-oxidant
enzyme which could be involved in the increased susceptibility of these patients to CVD. Hence, the levels of plasma MPO was
determined in healthy controls as well as in patients with CKD [stratified with the level of their kidney failure as CKD stages
II–V (end stage renal disease)]. Plasma MPO was assayed by a spectrophotometric method. Serum urea and creatinine were estimated
on a clinical chemistry analyzer using standard laboratory procedures. The mean plasma MPO levels were significantly lower
with advancing stages of renal failure (P < 0.001). There was a positive correlation between MPO and GFR (r = +0.89, P < 0.001) and a negative correlation with urea (r = −0.85, P < 0.001) and creatinine (r = −0.82, P < 0.001). While an inverse association was observed between plasma MPO and urea in CKD patients, such an association was
not observed in control subjects (P = 0.43). In conclusion, the decline in plasma MPO levels may be due to the inhibitory effect of uraemic toxins on the enzyme. 相似文献
959.
960.
Biofuel production has recently attracted much attention. Some anticipate substantial social and environmental benefits, while at the same time expecting sound profitability for investors. Others are doubtful, envisaging large trade-offs between the pursuit of social, environmental and economic objectives, particularly in poor countries in the tropics. The paper explores these issues in Tanzania, which has been an African forerunner in the cultivation of a bio-oil shrub called Jatropha curcas L. We trace how isolated Jatropha biofuel experiments developed since early 2005 towards a sectoral production and innovation system, and we investigate to what extent that system has been capable of developing and maintaining sustainable practices and producing sustainable outcomes. The application of evolutionary innovation theory allows us to view the developments in the sector as a result of evolutionary variation and selection on the one hand, and revolutionary contestation between different coalitions of stakeholders on the other. Both these processes constitute significant engines of change. While variation and selection are driven predominantly by localised technical and agronomic learning, the conflict-driven dynamics are highly globalised and occur primarily as a result of reflexive learning about problematic sustainability impacts. The sector is found to have moved some way towards a full sectoral innovation and production system, but it is impossible to predict whether a viable sector with a strong “triple bottom line” orientation will ultimate emerge, since many issues surrounding the social, environmental and financial sustainability still remain unresolved, especially relating to local and global governance. 相似文献