Negotiating rare book purchases     

Lorenzo A. Zeugner  Jr.   《Library Collections, Acquisitions, and Technical Services》2003,26(4):367-368

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EFFECTS OF TEACHER–STUDENT RELATIONSHIPS ON PEER HARASSMENT: A MULTILEVEL STUDY     

Beatriz Lucas‐Molina  Ariel A. Williamson  Rosa Pulido  Alicia Prez‐Albniz 《Psychology in the schools》2015,52(3):298-315

Peer harassment is a major social problem affecting children and adolescents internationally. Much research has focused on student‐to‐student harassment from either an individual or a multilevel perspective. There is a paucity of multilevel research on students’ relationships with the classroom teacher. The purpose of this study was to use a socioecological perspective to examine the relationships between individual student‐level characteristics, problematic teacher–student relationships, and student‐reported peer harassment. A total of 1,864 children (50.7% female) aged 8 to 13 years (M = 9.82, SD = 1.24), nested in 27 schools (58.2% public) in Spain, participated in the study. Ninety‐four homeroom teachers reported on teacher–student relationships, and students completed self‐report measures related to peer harassment and teacher–student relationships. Multilevel models showed that relationships between students and teachers exerted a varying degree of influence on classroom levels of peer harassment. Specifically, student‐reported teacher support was associated with diminished student‐reported peer victimization, whereas direct and indirect student‐reported teacher‐to‐student aggression was associated with increased peer victimization. Additionally, student‐reported student‐to‐teacher aggression and teacher‐to‐student aggression were associated with increased student‐reported peer aggression. Teacher‐reported variables at the classroom level, however, contributed little to student‐reported outcomes. Results are discussed in the context of future research on relationships between teachers and students.  相似文献   

Resting Bradycardia,Enhanced Postexercise Heart Rate Recovery and Cardiorespiratory Fitness in Recreational Ballroom Dancers     

Carlos Janssen Gomes da Cruz  Guilherme Eckhardt Molina  Luiz Guilherme Grossi Porto  Luiz Fernando Junqueira Jr 《Research quarterly for exercise and sport》2017,88(3):371-376

Purpose: In a cross-sectional study design, we evaluated the resting heart rate (HR_baseline) and exercise and postexercise stress test-related chronotropic responses in male practitioners of recreational ballroom dancing (BD; n = 25, M_age = 26.6 ± 6.1 years) compared to a control group of insufficiently active nondancers (CG; n = 25, M_age = 25.9 ± 4.5 years). Method: All participants underwent a submaximal exercise test. At 85% of the maximal predicted HR, the recovery protocol was started, and heart rate recovery (HRR) was recorded during 1-min intervals for 5 min. Results: Compared with CG, BD showed lower HR_baseline (70 beats per minute [bpm] vs. 62 bpm, respectively, U = 143, p < .05, ES = .46), lower preexercise HR (94 bpm vs. 86 bpm, U = 157, p < .05, ES = .42), longer exercise test duration (346 s vs. 420 s, U = 95.5, p < .05, ES = .59), and higher HRR for 5 min postexercise (U = 1.29–1.89, p < .05, ES = .33–.50) as follows: 1st min (32 bpm vs. 40 bpm), 2nd min (45 bpm vs. 53 bpm), 3rd min (51 bpm vs. 58 bpm), 4th min (55 bpm vs. 59 bpm), and 5th min (59 bpm vs. 63 bpm). The coefficient of HRR from the 1st min to the 5th min postexercise was similar in both groups (U = 229–311, p > .05, ES = < .10–.22). Conclusion: Heightened cardiovascular functional status characterized by favorable enhanced chronotropic dynamics appears to occur in practitioners of recreational ballroom dancing, which suggests that this modality of exercise may result in health benefits.  相似文献   

Exploring the effects of substituting basketball players in high-level teams     

Miguel-Ángel Gómez  Roberto Silva  Alberto Lorenzo  Rasa Kreivyte  Jaime Sampaio 《Journal of sports sciences》2017,35(3):247-254

Substituting basketball players during competition is a key process to optimise collective performance. Available research on this topic is scarce, probably due to the difficulty in isolating these effects; thus, the aim of this study was to identify the temporal effects of substitutions in basketball (Spanish professional basketball league). The sample was composed of 1118 substitutions gathered from 21 basketball games. The analysed variables were coach-controlled (player and team’s personal fouls, player in and player out roles, player’s in and out minutes on-court and timeout situation); on-court (foul committed, free throws, 2- and 3-point field-goal effectiveness) and situational variables (scoreline, quality of opposition, game location and game quarter). The results showed positive scoring performances after the substitution for all the analyses. During the first quarter, there were significant effects for fouls committed, scoreline and game location after the substitution. The player’s out personal fouls, free-throw effectiveness, player in, minutes on-court player in, timeout situation and 3-point field-goal effectiveness were significant during the second quarter. The team’s personal fouls, game location, and scoreline were identified as important in the third quarter. The fourth quarter did not show significant effects on the independent variables. Current findings allow optimising coaches’ plans and team management of on-court and bench players throughout the game.  相似文献   

A Study of Prospective Primary Teachers’ Conceptions of Teaching And Learning School Geometry     

Manuel Barrantes  Lorenzo J. Blanco 《Journal of Mathematics Teacher Education》2006,9(5):411-436

There are two basic guiding referents in the present investigation: the teaching and learning of school-level geometry (basic concepts of Euclidian geometry and measure) and the analysis of the conceptions of prospective primary teachers in Spain. The work assumes that such conceptions appear and develop during school years, and that consequently, for the prospective teachers to learn to teach mathematics, account must be taken of the requirements that arise from these conceptions themselves and from the prospective teachers’ knowledge of school-level mathematics. The objective of the study was to describe and analyse prospective primary teachers’ conceptions of school-level geometry and it teaching and learning. To this end, we considered the hypothesis that the students’ memories and expectations provide information with which to characterize their conceptions of the field of geometry and its teaching/learning at the primary school level.  相似文献   

Effectiveness during ball screens in elite basketball games     

Miguel-Ángel Gómez  Otavio Battaglia  Alberto Lorenzo  Jorge Lorenzo  Sergio Jiménez  Jaime Sampaio 《Journal of sports sciences》2015,33(17):1844-1852

Ball screens are one of the most frequently used tactical behaviour in elite basketball games. The aim of the present study was to identify their predictors of success related to time, space, players, and tasks performed. The sample was composed of 818 ball screens corresponding to 20 close games (mean differences in score of 3.1 ± 0.8 points) randomly selected from the playoff games of the Spanish Basketball League (2008–2011). Classification tree analysis (CHAID) was used to analyse which variable or combination of variables, better predicts effectiveness during ball screens. The main results allowed identifying interactions with dribbler actions after the screen and the orientation of the screen on the ball. The results showed no interaction with game quarter and quarter minute temporal-related variables in both analyses. The present findings allow improving coaches’ strategic plans that involve selecting the most appropriate offensive approach when performing ball screens.  相似文献   

Analysis of integrated STATCOM-SMES based on three-phase three-level multi-pulse voltage source inverter for high power utility applications     

Marcelo G. Molina  Pedro E. Mercado 《Journal of The Franklin Institute》2011,348(9):2350-2377

This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   

Methods for documenting historical agro-industrial buildings: a comparative study and a simple photogrammetric method     

P. Arias  C. Ordez  H. Lorenzo  J. Herraez 《Journal of Cultural Heritage》2006,7(4):350-354

As an important element in the cultural heritage of a people, traditional rural constructions need to be conserved over time. Graphic and metric documentation methods play a key role in the preservation of cultural heritage. In this paper different existing methods of graphic and metric documentation are analysed in order to select the most suitable for the documentation of agro-industrial buildings according to their characteristics. The selected one is a simple close-range photogrammetry method, which is affordable and easy to understand for non experts. It is based on the use of plumb lines, a conventional digital camera and monoscopic restitution. The application of the method is illustrated in a particular case consisting on the graphic and metric documentation of a windmill. Also the accuracy of the method is evaluated in this particular case.  相似文献   

Assessment of seismic vulnerability of art objects: The “Galleria dei Prigioni” sculptures at the Accademia Gallery in Florence     

Luisa Berto  Tommaso Favaretto  Anna Saetta  Fabrizio Antonelli  Lorenzo Lazzarini 《Journal of Cultural Heritage》2012,13(1):7-21

The seismic assessment of art objects requires a multidisciplinary approach and the definition of a specific methodology for evaluating the level of safety and the possible interventions necessary for seismic risk prevention, finding a compromise between safety and conservation. This paper describes a first step in this direction, in which the different aspects of the procedure, from knowledge path of the art object to the structural analysis, were studied in the six Michelangelo's statues located in the “Galleria dei Prigioni” (Slaves’ Gallery) at the Accademia Gallery of Florence. We showed that the general principles and criteria expressed in the “Italian Guidelines for evaluation and mitigation of seismic-risk to cultural heritage”, which are specifically devoted to masonry constructions, could be profitably extended to other artworks, like statues, starting from historical research, geometrical survey and material characterization, up to the developing of specific methods of analysis. This research could be the base for future studies to be performed concerning the prevention of seismic damage of art objects, including both bare minimum interventions and specific devices, such as isolation systems.  相似文献   

Lenguaje y rendimiento escolar: Un estudio predictivo     

Grace Shum  Angeles Conde  Carmen Díaz  Francisco Martínez  Lorenzo Molina 《Cultura y Educación》2013,25(5):69-79

La incidencia de las competencias lingüistícas del escolar sobre las adquisiciones escolares en las demás áreas del currículum es una realidad que todos los maestros pueden comprobar día a día. En este trabajo se investiga esa incidencia, medida a través de la variable fracaso escolar, y sus resultados podrían permitir extraer algunos principios de intervención educativa precoz en algunos aspectos del lenguaje cruciales para la escolaridad posterior.  相似文献