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71.
ABSTRACT

In recent years, technology has made it possible, and at times critical, for college and university presidents to increase their campus-wide public communication. However, there is little research that analyses these frequent and timely presidential communications. Using grounded theory, this study took steps to fill this gap by analysing the unprecedented response campuses had to the 2016 United States presidential election of Donald Trump. The analysis focused on the responses of presidents from the fifty state flagship universities and found emergent themes of unity, contentious election, negative event, university values, civil dialogue, services offered, and emotional rhetoric, while also finding significance in whether the letters were sent proactively or reactively.  相似文献   
72.
This study aimed to compare youth football players’ performance during two small-sided games with different pitch orientation: i) 40x30m and ii) 30x40m formats. Twenty under-15 players (age = 14.1 ± 0.5 years) participated in nine GK+4vs4+GK situations in each format, with the duration of six minutes each. Positional data were collected using individual GPS units, and computed for tactical and physical performance indicators. The SSG were video recorded, using notational analysis for collecting technical indicators. A novel method that incorporates time dependent notational information with spatiotemporal data was used to compute multidimensional parameters. Standardised effect sizes and non-clinical magnitude-based inferences were used to compare formats. Results showed that players covered more distance at higher intensities, presented more passes and dribbles and were more synchronised in the longitudinal axis while playing in the 40x30m pitch. In the 30x40m pitch, results showed a lower distance between team centroids, higher number of shots, more lateral passes and a wider team positioning. Multidimensional indicators, as players position and distance to the closest defender while shooting, revealed a more constant distance between attacker and defender in the 40x30m pitch. These results highlight the importance of integrating information from different indicators for a contextually valid information.  相似文献   
73.
The aim of this study was to analyse the effects of a combined strength-training programme (full-back squat, YoYoTM leg curl, plyometrics and sled towing exercises) on performance in elite young soccer players and to examine the effects when this training programme was performed one or two days per week. Thirty-six male soccer players (U-17 to U-19) were recruited and assigned to experimental groups (EXP1: 1?s?w?1; EXP2: 2?s?w?1) or a control group (CON). Performance was assessed through a countermovement jump (CMJ) test (relative peak power [CMJPP] and CMJ height [CMJH]), a 20-m linear sprint test with split-times at 10-m, and a change of direction test (V-cut test) 1 week before starting the training programme and also 1 week after performing such training programme. Within-group analysis showed substantial improvements in CMJ variables (ES: 0.39–0.81) and COD (ES: 0.70 and 0.76) in EXP1 and EXP2, while EXP2 also showed substantial enhancements in all linear sprinting tests (ES: 0.43–0.52). Between-group analysis showed substantially greater improvements in CMJ variables (ES: 0.39–0.68) in experimental groups in comparison to CON. Furthermore, EXP2 achieved a substantial better performance in 20-m (ES: 0.48–0.64) than EXP1 and CON. Finally, EXP2 also showed greater enhancements in 10-m (ES: 0.50) and V-cut test (ES: 0.52) than EXP1. In conclusion, the combined strength-training programme improved jumping ability, independently of training frequency, though the achievement of two sessions per week also enhanced sprinting abilities (linear and COD) in young soccer players.  相似文献   
74.
SEAD method estimates the direction-of-arrival angles on an uniformly linear array based on the difference between the two largest singular values, what is called differential spectrum. Although it presented an outstanding performance, the ability to indicate the source positions was not elucidated yet. Inspired by the differential spectrum formulation we derived a total differential spectrum and found out that the matrix norm induced by the vector 2-norm of a modified spatial covariance matrix can be used to estimate the direction-of-arrival of multiple plane waves. Indeed we show that matrix norms are estimators and we propose their use instead of the singular value decomposition in SEAD-based methods. We present a general mathematical expression in order to explicit the operating principles of the proposed methods. Consequently, we were able to explain how the relation between the arriving and the search angles produces the larger peaks on the differential spectrum. To evaluate the important role played by matrix norms, a thousand experiments were carried out. They showed that the proposed approach proved to be as accurate as the previous SEAD-based methods, while providing a significant reduction on runtime. It also outperformed well-established methods like MODEX regarding the estimation error.  相似文献   
75.
76.
The United States National Library of Medicine (NLM) has the largest collection of biomedical information products and services in the world. Little is known of the extent to which librarians in sub-Saharan Africa are aware of and use these resources. The study's aim was to assess knowledge and frequency of use of NLM's biomedical information products and services among African librarians. Forty-three of the 50 delegates at the 11th biannual Congress of the Association of Health Information and Libraries in Africa (AHILA) participated in the study. The findings showed that participants' knowledge of NLM information products and services was low and that there is a need for increased awareness and training in the use of NLM's information products and services in order for users on the African continent to effectively benefit from them.  相似文献   
77.
Robert M. Honderson's D. W. Griffith: The Years at Biograph (Farrar, Straus & Giroux, $7.50)

Martin Levin's edited collection, Hollywood and the Great Fan Magazines (Arbor House/ World, $10.00)

Kalton C. Lahue and Sam Gill's Clown Princes and Court Jesters (A.S. Barnes, $8.50)

Collecting Classic Films (Hastings House, $6.95)

Sheilah Graham's The Garden of Allah (Crown, $5.95)

Hugo Munsterberg's The Film: A Psychological Study (sub-titled The Silent Photoplay in 1916) (Dover Paperbacks, $2.00)

Sergei Eisenstein's Notes of a Film Director (Dover Paperbacks, $3.00)

Jay Leyda's Film Essays and a Lecture (Praeger Paperbacks, $2.95)

George P. Garrett, O.B. Hardison Jr., and Jane R. Gelfman, Film Scripts One (Appleton-Century-Crofts, price to be set)

Peter Noble's The Negro in Films (Port Washington, NY: Konnihat Press, $10.00)

Eileen Bowser's edited collection, Film Notes (Museum of Modern Art, $5.00)  相似文献   
78.
Mobile devices facilitate the use of mobile services that are similar to services used via fixed Internet connections. The objective of this article is to assess displacement effects between fixed and mobile Internet services, and to research the role of technical capabilities of mobile handsets and demographics as moderators. This study is based on a sample of 628 respondents who have access to fixed and mobile Internet services. The respondents' usage of services was analyzed. An online questionnaire was used to collect data on the use of information, communication, entertainment, and transaction services. Mobile Internet reinforces, rather than replaces, Internet usage. When people possess an iPhone® or (mobile) laptop, this reinforcement effect is present for entertainment services. With respect to transaction services, the Blackberry® makes a stronger case. With the exception of gender, demographic characteristics do not have a moderating effect. Women display a stronger reinforcement effect than men in relation to transaction services. To the best of our knowledge, no study to date has investigated the displacement effects of fixed Internet services by the mobile handset. This empirical study contributes to the literature regarding the displacement effects of mobile Internet services.  相似文献   
79.
We summarize the argumentative theory of reasoning, which claims that the main function of reasoning is to argue. In this theory, argumentation is seen as being essentially cooperative (people have to listen to others' arguments and be ready to change their mind) but with an adversarial dimension (their goal as argument producers is to convince). Consistent with this theory, the experimental literature shows that solitary reasoning is biased and lazy, whereas reasoning in group discussion produces good results, provided some conditions are met. We formulate recommendations for improving reasoning performance, mainly, to make people argue more and better by creating felicitous conditions for group discussion. We also make some suggestions for improving solitary reasoning, in particular to maximize students' exposure to arguments challenging their positions. Teaching people about the value of argumentation is likely to improve not only immediate reasoning performance but also long-term solitary reasoning skills.  相似文献   
80.
Providing low cost, high quality educational services to growing numbers of multilingual communities is perhaps one of the greatest challenges facing large urban school districts. In the Los Angeles urban area, adult students who wish to attend English as a Second Language (ESL) classes are presently constrained by the limitations of school resources, public transportation and growing levels of crime and street violence. Urban distance learning programmes may provide the best alternative to meet the educational needs of Limited English Proficient (LEP) adult students because it can service large numbers of students who are separated from their schools by geographical distance, safety, convenience, transportation, etc. Using perceptual mapping and conjoint analysis methodologies, this study analytically identifies and examines the design features or attribute characteristics of an ESL urban distance learning programme for LEP adults. Using focus groups as the basis to identify these attributes, perceptual mapping methods point to a market niche in developing technology‐driven, low‐cost distance learning programmes for these students. A conjoint analysis survey finds that LEP students generally favour distance learning programmes where ‘cost’, ‘effectiveness’ and ‘assessment’ are the primary attribute components.  相似文献   
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