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21.
Nathan H. Field Sophia Choukas-Bradley Matteo Giletta Eva H. Telzer Geoffrey L. Cohen Mitchell J. Prinstein 《Child development》2024,95(3):879-894
This study examined whether conformity to high- but not low-status e-confederates was associated with increases in identification with popular peers and subsequent increases in self-esteem. A sample of 250 adolescents (55.1% male; Mage = 12.70 years; 40.3% White, 28.2% Black, 23.4% Hispanic/Latino, and 7.7% multiracial/other) participated in a well-established experimental chat room paradigm where they were exposed to norms communicated by high- and low-status e-confederates. Results revealed that for boys in the high-status condition only, but not girls, the positive relation between conformity and self-esteem was mediated by greater response alignment with popular peers. These findings bolster prior research by suggesting that conformity to popular peers may be partly motivated by drives for self-esteem and alignment with a valued reference group. 相似文献
22.
Martino Colonna Nicola Pazi Matteo Moncalero Claudio Gioia Federico De Bon Davide Giovanelli Elisabetta Farella 《Sports Engineering》2017,20(4):275-282
We have performed a study on the thermo-formation process of plastic shells of boots for winter sports. The aim of the work has been to determine how the process parameters can improve the ergonomic and thermal comfort for athletes and winter sports participants. We have found that the initial deformation and memory effect are strongly influenced by the type of thermoplastic material used, heating time and cooling procedure. We have also found that the ovens currently used for this process are not correctly designed to obtain an efficient heat transfer and, therefore, a heating time of at least 12 min is necessary to achieve an average deformation of more than 2 mm. The measure of the boot flexural stiffness has shown that there are no changes in the load–deflection behavior after the thermo-formation process of a ski boot made of thermoplastic polyurethane. We have also found that the thermo-formation process decreases the pressure on skier’s feet of more than five times and, therefore, improves the comfort of the skier. 相似文献
23.
Lisanne L. Stone Matteo Giletta Mara Brendgen Roy Otten Rutger C.M.E. Engels Jan M.A.M. Janssens 《Early childhood research quarterly》2013
A key factor identified in friendship formation and stability is similarity. Homophily of externalizing problems has been reported frequently, but less attention has been directed at homophily of internalizing problems. Whether young children who are friends resemble each other in their internalizing problems is thus largely unknown. In order to increase understanding of the social risk factors implicated in the etiology of internalizing problems, it is important to establish whether internalizing problems cluster in friendships. The present study examines homophily of internalizing problems while controlling for externalizing problems in a sample of children aged 4–8. 相似文献
24.
A historical case study concerning the serious doubts that arose in early 1930s about the validity of the law of energy conservation in nuclear disintegrations, and the hypothesis of neutrino, will be closely analyzed with the goal of promoting understanding of the nature of science. This work is based upon primary archival and printed sources, with a particular focus on the proceedings of the first International Conference of Nuclear Physics which was held in Rome on October 1931. 相似文献
25.
Matteo Leone 《Science & Education》2014,23(4):923-953
The present paper advocates the use of History of Science into the teaching of science in primary education through a case study in the field of electricity. In this study, which provides both historical and experimental evidence, a number of conceptual difficulties faced by early nineteenth century physicists are shown to be a useful tool to detect 5th grade pupils’ conceptions about the simple electric circuits. This result was obtained through the administration of schematics showing circuital situation inspired to early 1800s experiments on the effects of electric current on water electrolysis and on the behaviour of magnetic compasses. It is also shown that the detecting of pupils’ alternative ideas about electric current in a circuit is highly dependent on the survey methodology (open ended questions and drawings, multiple-choice item, connecting card work, and history of science tasks were considered in this study) and that the so-called “unipolar model” of electric circuit is more pervasive than previously acknowledged. Finally, a highly significant hybrid model of electric current is identified. 相似文献
26.
Gabriel Lima-Oliveira Gian Luca Salvagno Giuseppe Lippi Elisa Danese Matteo Gelati Martina Montagnana Geraldo Picheth Gian Cesare Guidi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(3):343-349
Background:
Presently the necessity of fasting time for coagulation tests is not standardized. Our hypothesis is that this can harm patient safety. This study is aimed at evaluating whether a light meal (i.e. breakfast) can jeopardize laboratory coagulation tests.Materials and methods:
A blood sample was firstly collected from 17 fasting volunteers (12 h). Immediately after blood collection, the volunteers consumed a light meal. Then samples were collected at 1, 2 and 4 h after the meal. Coagulation tests included: activated partial thromboplastin time (APTT), prothrombin time (PT), fibrinogen (Fbg), antithrombin III (AT), protein C (PC) and protein S (PS). Differences between samples were assessed by Wilcoxon ranked-pairs test. The level of statistical significance was set at P < 0.05. Mean % differences were determined and differences between and baseline and 1, 2 and 4h samples were compared with reference change value (RCV).Results:
A significantly higher % activity of AT was observed at 1 h and 4 h after meal vs. baseline specimen [113 (104–117) and 111 (107–120) vs. 109 (102–118), respectively; P = 0.029 and P = 0.016]. APTT at 2 h was found significantly lower than baseline samples [32.0 (29.9–34.8) vs. 34.1 (32.2–35.2), respectively; P = 0.041]. The results of both Fbg and PS tests were not influenced by a light meal. Furthermore, no coagulation tests had significant variation after comparison with RCV.Conclusion:
A light meal does not influence the laboratory coagulation tests we assessed, but we suggest that the laboratory quality managers standardize the fasting time for all blood tests at 12 hours, to completely metabolize the lipids intake. 相似文献27.
Stefano Ceccon Elena Ceseracciu Zimi Sawacha Giorgio Gatta Matteo Cortesi Claudio Cobelli 《Journal of sports sciences》2013,31(3):276-287
Abstract Kinematic analysis of swimming is of interest to improve swimming performances. Although the video recordings of underwater swimmers are commonly used, the available methodologies are rarely precise enough to adequately estimate the three dimensional (3D) joint kinematics. This is mainly due to difficulties in obtaining the required kinematic parameters (anatomical landmarks, joint centres and reference frames) in the swimming environment. In this paper we propose a procedure to investigate the right upper limb’s 3D kinematics during front crawl swimming in terms of all elbow and shoulder degrees of freedom (three rotations of the shoulder, two of the elbow). The method is based upon the Calibrated Anatomical Systems Technique (CAST), a technique widely used in clinics, which allows estimation of anatomical landmarks of interest even when they are not directly visible. An automatic tracking technique was adopted. The intra-operator repeatability of the manual tracking was also assessed. The root mean squared difference of three anatomical landmarks, processed five times, is always lower than 8 mm. The mean of the root mean squared difference between trajectories obtained with the different methodologies was found to be lower than 20 mm. Results showed that complete 3D kinematics of at least twice as many frames than without CAST can be reconstructed faster and more precisely. 相似文献
28.
Matteo Dellepiane Nicolò Dell’Unto Marco Callieri Stefan Lindgren Roberto Scopigno 《Journal of Cultural Heritage》2013,14(3):201-210
Several new tools to obtain three-dimensional information from unorganized image sets are now available for the public use. The main advantage of this software, which is based on dense stereo matching, is the possibility to generate 3D content without the need of high-cost hardware (e.g. 3D scanning devices). Nevertheless, their use in real-world application domains (like cultural heritage) is still not very diffused, due to the non-straightforward usability of the raw data produced. In this paper, we investigate the use of automatic dense stereo reconstruction tools for the monitoring of an excavation site. A methodology for the effective acquisition and processing of data is presented. In addition, the results of the data assessment demonstrate the repeatability of the data acquisition process, which is a key factor when qualitative analysis is performed. The use of three-dimensional data is integrated in an open source mesh processing tool, thus showing that a spatio-temporal analysis can be performed in a very intuitive way using off-the-shelf or free/open digital tools. Moreover, the use of peculiar rendering and the creation of snapshots from arbitrary points of view increase the amount of documentation data, and suggest a perfect integration of data produced with dense stereo matching in the future standard documentation for excavation monitoring. 相似文献
29.
The purpose of the study was to identify the optimal body shape and composition associated with physical fitness levels of children living in urban and rural areas of Italy. A total of 7102 children (11–14 years) were assessed for weight, height, percentage body fat (FM%), sit-and-reach flexibility (SAR), standing broad jump (SBJ) and sit-ups (SUP). A multiplicative allometric model, Y = a · massk1 · heightk2 ·ε, was used to predict the physical outcome variables Y = SBJ and SUP. The model was expanded to incorporate FM% and SAR as follows Y = a · massk1 · heightk2 · FM%k3 · exp(b· FM% + c· SAR) ·ε. Note that FM% was incorporated as a “gamma function” that allows an initial growth, and subsequent decline in Y as FM% increases in size. Although having an ectomorph body shape appears advantageous, being too thin appears detrimental to the strength outcomes. Being flexible would also benefit physical fitness levels. Finally, our results indicate that ursban children aged 11–14 have superior strength outcomes compared with rural children, having controlled for differences in body shape and composition, a finding that may be associated with rural environments having fewer exercise facilities compared with urban conurbations. 相似文献
30.
The use made of evaluation output is crucial for understanding the position and effectiveness of evaluation systems. This
article examines the development of evaluation in the Italian university system from the 1990 s onwards where serious problems
have been and continue to be addressed in the use of evaluation output to improve academic activities and make universities
accountable for their behaviour. There is a tendency for evaluation to generate inappropriate or undesired effects and for
those being assessed to adopt opportunistic behaviour. Underestimation of the universities’ organisational features is the
main reason for so many difficulties. 相似文献