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211.
Perhaps nothing strikes more fear into the hearts of all tenure-track professors than the process itself. Are four papers in this journal good enough? Are eight papers in another okay? What if someone doesn’t like me or my area of research? These issues have plagued academia since the first essay was penned by the first researcher hundreds of years ago. While personal bias and journal preference continue to infect honest tenure reviews, solutions exist. This does not mean we have a magic bullet to solve issues of bullying or elitism. However, if we are honest in our desire to improve the Academy, we should avail ourselves of every possible tool for improvement. This essay is based on a survey sent to 2,500 mass communication educators. Of the almost 500 respondents, roughly 10% took the time to express emotions that ranged from fear and confusion to outright rage and anger, all because what ought to be clear is not. The author offers 10 ideas of how academia can improve its evaluation of new faculty, as well as a few suggestions regarding the unnecessary inclusion of personal issues in a process that ought to be about creating better researchers and teachers.  相似文献   
212.
Trust online can be a hazardous affair; many are trustworthy, but some people use the anonymity of the web to behave very badly indeed. So how can we improve the quality of evidence for trustworthiness provided online? I focus on one of the devices we use to secure others’ trustworthiness: tracking past conduct through online reputation systems. Yet existing reputation systems face problems. I analyse these, and in the light of this develop some principles for system design, towards overcoming these challenges. In providing better evidence for trustworthiness online, so we can also encourage people actually to be trustworthy more often, which is an ethically welcome outcome.  相似文献   
213.
Found in all eukaryotic cells, linker histones H1 are known to bind to and rearrange nucleosomal linker DNA. In vitro, the fundamental nature of H1∕DNA interactions has attracted wide interest among research communities-from biologists to physicists. Hence, H1∕DNA binding processes and structural and dynamical information about these self-assemblies are of broad importance. Targeting a quantitative understanding of H1 induced DNA compaction mechanisms, our strategy is based on using small-angle x-ray microdiffraction in combination with microfluidics. The usage of microfluidic hydrodynamic focusing devices facilitates a microscale control of these self-assembly processes, which cannot be achieved using conventional bulk setups. In addition, the method enables time-resolved access to structure formation in situ, in particular, to transient intermediate states. The observed time dependent structure evolution shows that the H1∕DNA interaction can be described as a two-step process: an initial unspecific binding of H1 to DNA is followed by a rearrangement of molecules within the formed assemblies. The second step is most likely induced by interactions between the DNA and the H1's charged side chains. This leads to an increase in lattice spacing within the DNA∕protein assembly and induces a decrease in the correlation length of the mesophases, probably due to a local bending of the DNA.  相似文献   
214.
We examined differences in anthropometry and training between 64 Triple Iron ultra-triathletes competing over 11.4 km swimming, 540 km cycling, and 126.6 km running, and 71 Ironman triathletes competing over 3.8 km swimming, 180 km cycling, and 42.2 km running. The association of anthropometry and training with race time was investigated using multiple linear regression analysis. The Triple Iron ultra-triathletes were smaller (P < 0.05), had shorter limbs (P < 0.05), a higher body mass index (P < 0.05), and larger limb circumferences (P < 0.01) than the Ironman triathletes. The Triple Iron ultra-triathletes trained for more hours (P < 0.01) and covered more kilometres (P < 0.01), but speed in running during training was slower compared with the Ironman triathletes (P < 0.01). For Triple Iron ultra-triathletes, percent body fat (P = 0.022), training volume per week (P < 0.0001), and weekly kilometres in both cycling (P < 0.0001) and running (P < 0.0001) were related to race time. For Ironman triathletes, percent body fat (P < 0.0001), circumference of upper arm (P = 0.006), and speed in cycling training (P = 0.012) were associated with total race time. We conclude that both Triple Iron ultra-triathletes and Ironman triathletes appeared to profit from low body fat. Triple Iron ultra-triathletes relied more on training volume in cycling and running, whereas speed in cycling training was related to race time in Ironman triathletes.  相似文献   
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During the belle époque, Belgium was a trend-setting nation in many domains, including motorised sports. Belgian automobile racers and pilots shattered world records and became international stars. Striking was the shift in sports. Indeed, around 1896, sporting members of the leisure class stepped from the bicycle into the automobile and, around 1908, from the automobile into the airplane. Although these motorised sports were extremely expensive, this article shows that sportsmen and sportswomen from the working class could achieve upward social mobility through their performances. The achievements of these motorised pioneers had a major impact and wide-ranging significance. They laid the foundations for the expansion of the automobile industry and the emergence of civilian and military aviation.  相似文献   
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218.

Teacher technology integration research on persistence is needed. Teachers’ persistence is strongly associated with their autonomous motivation, as defined by self-determination theory (SDT); however, most SDT-based studies have focused on teachers’ support and students’ motivation and well-being. SDT founders also recently suggested that future studies should include teacher motivation towards the use of technology. Accordingly, this experimental and longitudinal study aimed to investigate how the proposed support encouraged and sustained the low- and high- quality teachers’ integration practices. It proposed a school learning support intervention with three dimensions—leader, expert, and peer support—to meet teachers’ basic needs and thereby increase their motivation for and persistence in classroom technology integration. It had a sequential explanatory mixed-methods design, involved 122 school teachers and lasted for 22 months. Pre-, post- and delay- questionnaires and two arounds of interviews were used to collect the teachers perceptions on needs satisfaction and technology integration practices. The results suggest that the support increased the extent to which the teachers’ needs were met, resulting in more high-quality (student-centered) but not low-quality (lecturing) integration practices. However, the intervention sustained both types of integration practices. The findings offer three major empirical implications, makes two theoretical contributions, and offers four practical suggestions for researchers and practitioners.

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219.
Discrimination reversal learning has been used as a measure of species flexibility in dealing with changes in reinforcement contingency. In the simultaneous-discrimination, midsession-reversal task, one stimulus (S1) is correct for the first half of the session, and the other stimulus (S2) is correct for the second half. After training, pigeons show a curious pattern of choices: They begin to respond to S2 well before the reversal point (i.e., they make anticipatory errors), and they continue to respond to S1 well after the reversal (i.e., they make perseverative errors). That is, pigeons appear to be using the passage of time or the number of trials into the session as a cue to reverse, and are less sensitive to the feedback at the point of reversal. To determine whether the nature of the discrimination or a failure of memory for the stimulus chosen on the preceding trial contributed to the pigeons’ less-than-optimal performance, we manipulated the nature of the discrimination (spatial or visual) and the duration of the intertrial interval (5.0 or 1.5 s), in order to determine the conditions under which pigeons would show efficient reversal learning. The major finding was that only when the discrimination was spatial and the intertrial interval was short did the pigeons perform optimally.  相似文献   
220.
The SCOR (Supply Chain Operations Reference) Model Supply Chain Classroom Simulation is an in‐class experiential learning activity that helps students develop a holistic understanding of the processes and challenges of supply chain management. The simulation has broader learning objectives than other supply chain related activities such as the Beer Game. Competing supply chains work to produce and sell two products, each experiencing differential demand. Seasonal demand, time delays, quality defects, and disruptions offer complexities that are part of actual supply chain management. The behavioral dynamics of collaboration between various functional nodes is illustrated through students’ interactions as they try to achieve their role's objectives. Through their decisions and actions, students develop a practical understanding of the processes and complexities of supply chain management. The classroom simulation actively engages students, and has been used successfully in multiple courses at the undergraduate and graduate levels at multiple universities and by a major corporation during a manager training session. Assessments indicate that the simulation is an effective experiential learning activity. While it offers learning outcome flexibility, common debrief themes are SCOR model processes, supply chain relationships, information flow, seasonal demand, quality defects, reverse logistics, and supply chain disruptions.  相似文献   
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