A call for international research on COVID-19-induced brain dysfunctions     

Pedro A Valdes-Sosa  Alan C Evans  Mitchell J Valdes-Sosa  Mu-ming Poo 《国家科学评论(英文版)》2021,8(12)

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Cooperation in innovation activities: The importance of partners   总被引：1，自引：0，他引：1  

Pedro de Faria  Francisco Lima 《Research Policy》2010,39(8):1082-1092

This paper analyses the importance of cooperation partners for the development of innovation activities. We contribute to the literature on cooperation in innovation activities that seeks to identify the characteristics differentiating cooperative from non-cooperative firms by proposing a different approach to this problem. We distinguish firms according to their evaluation of cooperation partners in the development of innovation activities. We apply a probit selection model to account for the firm's decision to cooperate (or not). The data we use come from the Portuguese Third Community Innovation Survey. Our estimation results show that firms from high-technological industries, with higher levels of absorptive capacity and of innovation investment, who give importance to incoming spillovers management, and who cooperate with firms from the same group or with suppliers, place greater value on cooperation partners in the innovation process. Additionally, we also find that the factors influencing the importance attributed to cooperation activities are different from the ones behind the decision to cooperate.  相似文献   

Knowledge protection strategies of multinational firms—A cross-country comparison     

Pedro de Faria  Wolfgang Sofka 《Research Policy》2010,39(7):956-968

International knowledge spillovers, especially through multinational companies (MNCs), have recently been a major topic of discussion among academics and practitioners. Most research in this field focuses on knowledge sharing activities of MNC subsidiaries. Relatively little is known about their capabilities for protecting valuable knowledge from spilling over to host country competitors. We extend this stream of research by investigating both formal protection strategies (e.g. patenting) as well as strategic ones (secrecy, lead time, complex design). We conceptualize the breadth of firm's knowledge protection strategies and relate it to the particular situation of MNC subsidiaries. Moreover, we argue that their approaches differ with regard to host country challenges and opportunities. We address these issues empirically, based on a harmonized survey of innovation activities of more than 1800 firms located in Portugal and Germany. We find evidence that MNCs prefer broader sets of knowledge protection strategies in a host country with fewer opportunities for knowledge sourcing (Portugal). In Germany, though, they opt for narrower sets of knowledge protection strategies if they invest in innovation activities themselves. We deduce that these results are due to a need for reciprocity in knowledge exchanges to benefit fully from promising host country knowledge flows.  相似文献   

Classroom environment in the implementation of an innovative curriculum project in science education     

Mercedes Surez  Rosa Pías  Pedro Membiela  Dolores Dapía 《科学教学研究杂志》1998,35(6):655-671

A curriculum project can be positively or negatively influenced by the environment of the classroom in which it is implemented. Analysis of the perceptions of students, teachers, and external observers has allowed us to study the influence of classroom environment in the implementation of an innovative project in science education. The main conclusions indicate that even though the global evaluation is positive, more so among teachers than among students, there are differences between the perceptions of the participants, probably due to differences in interests and needs. Moreover, in the classroom environment, the teacher and the actual dynamic and spatial organization are of great importance, and it can be difficult to maintain interest or to achieve a satisfactory evaluation on the part of those students whose academic performance is lowest. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 655–671, 1998.  相似文献   

Math Achievement Trajectories Among Black Male Students in the Elementary- and Middle-School Years     

Afshin Zilanawala  Margary Martin  Pedro A. Noguera  Ronald B. Mincy 《Educational Studies A Journal of the American Educational Studies Association》2018,54(2):143-164

In this article, we analyze the variation in math achievement trajectories of Black male students to understand the different ways these students successfully or unsuccessfully navigate schools and the school characteristics that are associated with their trajectories. Using longitudinal student-level data from a large urban US city (n = 7,039), we analyze Black male students from one cohort to identify trajectories. We find a lack of growth in standardized math scores, suggesting that, on average, math proficiency among Black male students in our sample is declining over time. We found that the 4th-grade standardized math scores of subsidized-lunch students were somewhat lower than those of nonsubsidized students and those of retained students were substantially lower than their counterparts. The average math score of a Black male student's cohort appears to be the only variable amenable to policy manipulation that has a sizeable association with the growth of their standardized math scores, suggesting that putting Black male students in more challenging learning environments may be the best way to increase math proficiency over time. By themselves, other policy decisions (reducing student mobility, teacher turnover, or special education classification; increasing attendance or spending on after-school programming; or hiring more qualified or experienced teachers) all appear to have no or negligible associations with growth in math scores.  相似文献   

Hierarchical linear dynamical systems for unsupervised musical note recognition     

Goktug T. Cinar  Pedro M.N. Sequeira  Jose C. Principe 《Journal of The Franklin Institute》2018,355(4):1638-1662

In this paper we develop a new framework for time series segmentation based on a Hierarchical Linear Dynamical System (HLDS), and test its performance on monophonic and polyphonic musical note recognition. The center piece of our approach is the inclusion of constraints in the filter topology, instead of on the cost function as normally done in machine learning. Just by slowing down the dynamics of the top layer of an augmented (multilayer) state model, which is still compatible with the recursive update equation proposed originally by Kalman, the system learns directly from data all the musical notes, without labels, effectively creating a time series clustering algorithm that does not require segmentation. We analyze the HLDS properties and show that it provides better classification accuracy compared to current state-of-the-art approaches.  相似文献   

Spillovers in the production of knowledge: A meta-regression analysis     

Pedro Cunha Neves  Tiago Neves Sequeira 《Research Policy》2018,47(4):750-767

The production of knowledge was subjected to quantitative analysis in the second half of the twentieth century, following Arrow (1962). The determinants of knowledge and the externalities present in the innovation process were discussed with immediate policy influence. In particular, the presence and strength of the spillover of the pool of past knowledge has encouraged high subsidization of R&D in the most developed countries. We survey the empirical literature on the spillover effect in the production of knowledge and implement a meta-analytic regression. We discover that the average spillover effect is less than but close to one and is highly significant. We also find that the spillover effect tends to be greater when the estimation of knowledge production accounts for foreign inputs, and it tends to be lower when the estimation includes only rich economies, regional data are used, and the pool of knowledge is not the patent stock.  相似文献   

Protecting knowledge: How legal requirements to reveal information affect the importance of secrecy     

Wolfgang Sofka  Pedro de Faria  Edlira Shehu 《Research Policy》2018,47(3):558-572

Most firms use secrecy to protect their knowledge from potential imitators. However, the theoretical foundations for secrecy have not been well explored. We extend knowledge protection literature and propose theoretical mechanisms explaining how information visibility influences the importance of secrecy as a knowledge protection instrument. Building on mechanisms from information economics and signaling theory, we postulate that secrecy is more important for protecting knowledge for firms that have legal requirements to reveal information to shareholders. Furthermore, we argue that this effect is contingent on the location in a technological cluster, on a firm’s investment in fixed assets and on a firm’s past innovation performance. We test our hypotheses using a representative sample of 683 firms in Germany between 2005 and 2013. Our results support the moderation effect of a technological cluster and a firm’s investment in fixed assets. Our findings inform both academics and managers on how firms balance information disclosure requirements with the use of secrecy as a knowledge protection instrument.  相似文献   

Effects of a contrast training programme on jumping,sprinting and agility performance of prepubertal basketball players     

Pedro Ángel Latorre Román  Francisco Javier Villar Macias  Felipe García Pinillos 《Journal of sports sciences》2018,36(7):802-808

The purpose of this study was to examine the effects of a 10 week contrast training (CT) programme (isometric + plyometric) on jumping, sprinting abilities and agility performance in prepubertal basketball players. Fifty-eight children from a basketball academy (age: 8.72 ± 0.97 years; body mass index: 17.22 ± 2.48 kg/m²) successfully completed the study. Participants were randomly assigned to experimental groups (EG, n = 30) and control groups (CG, n = 28). The CT programme was included in the experimental group’s training sessions – twice a week – as part of their usual weekly training regime. This programme included 3 exercises: 1 isometric and 2 plyometric. Jumping, sprinting and agility performance were assessed before and after the training programme. Significant differences were found in posttest between EG and CG in sprint and T-test: EG showed better results than CG. Furthermore, there were significant differences in posttest-pretest between EG and CG in squat jump, countermovement jump, drop jump, sprint and T-test with the EG showing better results than CG. The CT programme led to increases in vertical jump, sprint and agility levels, so that the authors suggest that prepubertal children exhibit high muscular strength trainability.  相似文献   

Physical exercises for preventing injuries among adult male football players: A systematic review     

Jorge Pérez-Gómez  JoséCarmelo Adsuar  Pedro EAlcaraz  Jorge Carlos-Vivas 《运动与健康科学(英文)》2022,11(1):115-122

Background:Football is the most practised sport in the world and is associated with the risk of injuries in the players.Some studies have been published that identify injury prevention programs,but there is no review of the full body of evidence on injury prevention programs for use by football coaches.The aim of this article was to carry out a systematic review of published studies on injury prevention programs for adult male footballers,identify points of common understanding and establish recommendations that should be considered in the design of injury prevention strategies.Methods:PubMed and EMBASE databases were used to identify relevant published articles using the following keywords:"soccer"AND"injury"AND"prevention".Results:A total of 2512 studies were identified initially,but only 11 studies met the inclusion criteria,and their outcomes are presented.Results revealed that injury prevention programs in football have focused on strength training,proprioceptive training,multicomponent programs(balance,core stability,and functional strength and mobility),and warm-up programs.Conclusion:Based on results from the studies analyzed,football players can lower the incidence of match and training injuries by participating in dynamic warm-up programs that include preventive exercises before games or during training sessions,and by adding strength,balance,and mobility training to the training sessions.  相似文献