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Developmental Trajectories of Acculturation: Links With Family Functioning and Mental Health in Recent‐Immigrant Hispanic Adolescents 
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下载免费PDF全文 Seth J. Schwartz Jennifer B. Unger Byron L. Zamboanga David Córdova Craig A. Mason Shi Huang Lourdes Baezconde‐Garbanati Elma I. Lorenzo‐Blanco Sabrina E. Des Rosiers Daniel W. Soto Juan A. Villamar Monica Pattarroyo Karina M. Lizzi José Szapocznik 《Child development》2015,86(3):726-748
The present study was designed to examine acculturative changes, and their effects on mental health and family functioning, in recent‐immigrant Hispanic adolescents. A sample of 302 Hispanic adolescents was assessed five times over a 2½‐year period. Participants completed measures of Hispanic and U.S. practices, collectivist and individualist values, and ethnic and U.S. identity at each time point. Baseline and Time 5 levels of mental health and family functioning were also assessed. Latent class growth analyses produced two‐class solutions for practices, values, and identifications. Adolescents who increased over time in practices and values reported the most adaptive mental health and family functioning. Adolescents who did not change in any acculturation domain reported the least favorable mental health and family functioning. 相似文献
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Marcello Farina Sergio Bittanti Lorenzo Galleani 《Journal of The Franklin Institute》2009,346(5):449-469
Precision and reliability of timescales are of importance in many situations, in particular in satellite navigation systems (i.e., Galileo system). Motivated by the necessity to improve the precision and the reliability of such clock signals, we have explored the possibility to exploit control theory in clock steering methods. First of all we provide a more robust theoretical framework for the analysis of the process. Two novel control algorithms are here proposed aiming to meet metrological specifications. Numerical simulations have been performed in order to evaluate the performances of the new control systems. 相似文献
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Shaoliang Zhang Alberto Lorenzo Miguel-Angel Gómez Nuno Mateus Bruno Gonçalves Jaime Sampaio 《Journal of sports sciences》2018,36(22):2511-2520
The aim of this study was: (i) to group basketball players into similar clusters based on a combination of anthropometric characteristics and playing experience; and (ii) explore the distribution of players (included starters and non-starters) from different levels of teams within the obtained clusters. The game-related statistics from 699 regular season balanced games were analyzed using a two-step cluster model and a discriminant analysis. The clustering process allowed identifying five different player profiles: Top height and weight (HW) with low experience, TopHW-LowE; Middle HW with middle experience, MiddleHW-MiddleE; Middle HW with top experience, MiddleHW-TopE; Low HW with low experience, LowHW-LowE; Low HW with middle experience, LowHW-MiddleE. Discriminant analysis showed that TopHW-LowE group was highlighted by two-point field goals made and missed, offensive and defensive rebounds, blocks, and personal fouls; whereas the LowHW-LowE group made fewest passes and touches. The players from weaker teams were mostly distributed in LowHW-LowE group, whereas players from stronger teams were mainly grouped in LowHW-MiddleE group; and players that participated in the finals were allocated in the MiddleHW-MiddleE group. These results provide alternative references for basketball staff concerning the process of evaluating performance. 相似文献
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Lorenzo Righetto Alessandro Spelta Emanuele Rabosio Fabio Pammolli 《Journal of Informetrics》2019,13(2):583-592
Within the perimeter of patent collaboration networks, the average distance of collaborations and the number of countries involved per each collaboration have been shown to have increased steadily in time. Less attention, though, has been devoted to assessing whether this growth of cross-country collaborations is stable in time. To address this scientific question we focus on the identification of long-term correlations (i.e. temporal persistence). Our data set consists of time series of yearly average collaboration radii and of cross-border links in the Euro-American subsystem of the global collaboration network for the period 1978–2014. To investigate the fundamental persistence properties of these time series, we use Detrended Fluctuation Analysis, a method that allows us to measure long-term correlations in detrended signals. Also, we devise a general and original procedure to assess the statistical significance of results for short time series. Our results, showing that long-term correlations do exist in the majority of our signals, reinforce the hypothesis of a diminishing role of geographical distance in technological collaborations. Results at national level show that a significant degree of heterogeneity in persistence parameters can be detected within Europe, irrespectively of the efforts towards the set-up of an integrated European Research Area. 相似文献
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Annamaria Conti Nishant Dass Francesco Di Lorenzo Stuart J.H. Graham 《Research Policy》2019,48(3):799-812
This paper employs the 2008 financial crisis as an empirical setting to examine how investment strategies of venture capitalists (VCs) vary in the presence of a liquidity supply shock, and what the performance implications of these strategies are for their portfolio startups. We show that while, on aggregate, funded startups receive no less financing during the financial crisis than in non-crisis times, VCs allocate relatively more resources to startups operating in the VCs’ core sectors. We show that this skew allocation follows from VCs choosing to double down on their core-sector investing, rather than by a changed mix of investors or startups during the financial crisis. These effects are strongest for early-stage startups, for which information problems are most severe. Furthermore, these results are driven by the investment strategies of more-experienced VCs. Building on these findings, we find superior ex post performance among crisis-funded portfolio startups operating in more-experienced VCs’ core sectors. 相似文献
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This paper aims to analyse the pricing strategies of mobile communications operators and examine the role of demand characteristics in the development of new tariff plans. In so doing, we depart from a traditional industrial organization approach to price discrimination and interpret new tariff plans as innovations. In the spirit of Schumpeter, we look at competition in this sector as depending upon this form of innovation, and we argue that, given the specific features of the industry, the development of new tariff plans is strongly related to the users’ characteristics and behaviour. Our main point is that in a context of uncertainty, demand affects firms’ innovative strategies in two ways: first, by providing information on user behaviour and by increasing the capability of market segmentation; and second, by providing the incentives to innovate. This argument is supported by an empirical analysis carried out on the basis of an original dataset which includes all the tariff plans on offer in the history of the Italian market between 1992 and 2005. We find that both a firm's installed customer base and the level of market saturation play a role in shaping firms’ innovative pricing strategies, in terms of the number and characteristics of the new tariff plans. 相似文献
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Lorenzo Garcia 《Multicultural Perspectives》2013,15(2):20-24
In this study, I examine the perspectives of preservice teachers enrolled in a multicultural education course at a large predominately White Midwestern university. Past research on the development of multicultural attitudes and knowledge of White preservice teachers is inconclusive. In an effort to examine the multicultural perspectives of preservice teachers, 13 prospective teachers enrolled in required semester-long multicultural education courses were regularly interviewed and observed. Results of the study indicate that preservice teacher perspectives toward diversity were influenced by their social and educational histories; popular culture, such as the news media and movies; and the traditional structure of the teacher education program. The single course had minimal impact on their perspectives. Recommendations include infusing a multicultural perspective throughout the teacher education program and the development of collaborations between the program and culturally diverse schools. 相似文献
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Chiara Zoppirolli Lorenzo Bortolan Federico Schena Barbara Pellegrini 《Journal of sports sciences》2020,38(8):863-872
ABSTRACTWe aimed to evaluate the changes in double poling (DP) kinematics due to a long-distance cross-country skiing race in athletes with different performance levels. A total of 100 cross-country skiers, belonging to 10 different performance groups, were filmed on flat terrain 7 and 55 km after the start line, during a 58-km classical race. Cycle velocity, frequency and length decreased from the best to the lower-ranked group, while duty cycle increased (all P <.001). Between track sections, cycle velocity and length decreased, duty cycles increased (all P <.001) while frequency was unaltered (P =.782). Group*section interactions resulted for cycle velocity (P =.005). Considering all the participants together, % change in cycle velocity between sections correlated with % change in length and duty cycle (all P <.001). Thus i) skiers in better groups showed longer and more frequent cycles as well as shorter duty cycles than skiers in slower groups; ii) throughout the race all the groups maintained the same cycle frequency while decreasing cycle velocity and length; iii) better groups showed a lower reduction in cycle velocity. Individually, a low reduction in cycle velocity during the race related to the capacity to maintain long cycles and short duty cycles. 相似文献