The National Student Survey: validation in Portuguese medical students

The UK National Student Survey (NSS) is a sound and widely used instrument for assessing students’ academic experiences. We aimed to translate the NSS for Portuguese students and to validate the instrument in a sample of medical undergraduates. The research team translated and adapted the NSS for Portuguese students (NSS-P). The survey was administered on an online platform to 1,256 final-year students at eight Portuguese medical schools. A total of 329 medical students (69.9% female) replied to the NSS-P, a response rate of 26.2%. Confirmatory factor analysis showed that the original six-factor structure had an adequate fit to the data. Adequate internal consistency was observed for all the subscales. Medium to large correlations were found among all the subscale scores and between the subscale scores and the students’ overall satisfaction. Multiple regression showed that the scores on the Teaching, Organization and Management and Personal Development subscales significantly predicted the students’ overall satisfaction. Approximately 64% of the students reported being satisfied with the quality of their courses. Significant differences among the medical schools in their NSS-P scores were found. The NSS-P is a valid and reliable measure for assessing medical students’ perceptions of academic quality.     

Development of a scale of Sense of Community in university online courses

Creating a sense of community in online classes contributes to student retention and to their overall satisfaction with the course itself. This study aimed to develop a scale of sense of community of students attending online university courses. A series of ordinal exploratory factor analyses were conducted on data obtained from 839 students enrolled in Italian universities. Using an item analysis method, we were able to select the 36 most valid items from an original set of 60 items we had previously defined. These items are distributed across three related factors measuring membership, influence, and fulfillment of needs. This factorial structure replicates the McMillan and Chavis’s model of sense of community, upon the basis of which this scale was developed. The three factors presented good ordinal alpha and adequate convergent/divergent validity coefficients. The scale represents an efficient tool for the design, monitoring, and evaluation of online courses.     

小功率高频数字控制DC/DC 变换器设计

This paper models a low-power high-frequency digitally controlled synchronous rectifier （SR） OUCK converter. The converter is a hybrid system with three operation modes. Digital PID controler is used. Key problems such as quantization resolution of digital pulse-width modulation （DPWM） and steady-state limit cycles of digital control switching model power supply （SMPS） are discussed, with corresponding solutions presented. Simulation of a digital control synchronous buck is performed with a fixed-point algorithm. The results show that the described approach enables high-speed dynamic performance.     

"WE ARE ONE BIG, HAPPY FAMILY": BEYOND NEGOTIATION AND COMPULSORY HAPPINESS

A bstract .  Much recent scholarship on changing educational practices in Western families focuses on the idea that negotiation has become the dominant approach to family household management. In this essay, Bruno Vanobbergen, Michel Vandenbroeck, Rudi Roose, and Maria Bouverne-De Bie examine the idea of the negotiation model functioning as a directive. To illustrate this process, they demonstrate how the contemporary vocabulary about parental education affects the construction of parental beliefs and the concepts that define research. The authors first present a genealogy of negotiation by looking at constructions of childhood and parenthood, as well as the educational practices that shape, and are in turn shaped by, these constructions. They then turn their attention to the concept of the autonomous self and its implications for family relations and family household practices.     

Intergenerational preschool experiences and the young child: Potential benefits to development

We conducted an exploratory study evaluating the potential impact of intergenerational programming (IG) on children's socio-emotional development, behavior, school performance, and attitudes and behavior toward older adults. Children currently in kindergarten through second grade (age range: 6–8 years old) who previously attended one of two preschools of comparably high quality and serving families of similar demographic profiles were compared 1–3 years after graduating from their respective programs. One program offered intergenerational (IG) programming while the other was a traditional single-generation program (SG). Face-to-face interviews were conducted with the child and one of his/her parents in their home. In addition, a mail survey was sent to the child's school teacher. The study explored whether children exposed to IG had differential outcomes on specific measures as compared to children who attended the SG program. Results showed that children from the IG program had higher levels of social acceptance, a greater willingness to help and greater empathy for older people, slightly more positive attitudes, and better able to self-regulate their behavior than children from the SG program. Although limited by the lack of a pre–post experimental design, these results provide initial evidence that an IG program can offer additional benefits to children's development whose impact can last into the their early school age years.     

Cooperative methods and self-regulated strategies development for argumentative writing

The authors analyze the efficacy of a cooperative method associated with self-regulated strategy development (SRSD) for argumentative writing compared with a SRSD single approach. Seven teachers and 230 ninth-grade students from three middle schools participated in the present study in which teachers were part of a practice-based professional development program. Schools were assigned either to the experimental group or to the comparison group. Over a three-month period, all students were taught SRSD strategies. After this period, students from the experimental group participated in a cooperative setting, whereas the comparison group followed the SRSD only. The results indicated that students in the experimental group made statistically significant greater gains in structural argumentative elements and in the quality of writing texts immediately after the intervention and one month later. Thus, the study provides evidence for the benefits of adding a cooperative setting to SRSD in implementing argumentative writing skills.     

How Computer-Assisted Learning Influences Medical Students' Performance in Anatomy Courses

Anatomy is an essential subject of the medical curriculum. Despite its relevance, the curricular time and logistical resources devoted to teaching anatomy are in decline, favoring the introduction of new pedagogical approaches based on computer-assisted learning (CAL). This new pedagogical approach provides an insight into students' learning profiles and features, which are correlated with knowledge acquisition. The aim of this study was to understand how training with CAL platforms can influence medical students' anatomy performance. A total of 611 medical students attending Musculoskeletal Anatomy (MA) and Cardiovascular Anatomy (CA) courses were allocated to one of three groups (MA Group, CA Group, and MA + CA Group). An association between the performance in these anatomy courses and the number of CAL training sessions was detected. In the MA Group (r = 0.761, P < 0.001) and the MA + CA Group (r = 0.786, P < 0.001), a large positive correlation was observed between musculoskeletal anatomy performance and the number of CAL training sessions. Similarly, in the CA Group (r = 0.670, P < 0.001) and the MA + CA Group (r = 0.772, P < 0.001), a large positive correlation was observed between cardiovascular anatomy performance and the number of CAL training sessions. Multiple linear regression models were performed, considering either musculoskeletal or cardiovascular anatomy performance as the dependent variable. The results suggest that using CAL platforms to study has a positive dose-dependent effect on anatomy performance. Understanding students' individual features and academic background may contribute to the optimization of the learning process.     

Demand and innovation in services: The case of mobile communications

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.     

Analysis of elbow muscle strength parameters in Brazilian jiu-jitsu practitioners

Upper-body dynamic and isometric maximum strength are essential components for success in Brazilian jiu-jitsu (BJJ). This study was aimed at analysing strength parameters in the elbow flexor and extensor muscles of BJJ practitioners. Participants (n = 28) performed maximum isometric contractions of elbow flexors and extensors to determine peak torque (PT), rate of force development (RFD), and the torque–angle (T–A) relationship at elbow angles of 45°, 60°, 75°, 90°, 105°, and 120°. Additionally, concentric and eccentric PTs were measured at 1.04 rad·s^-1. Student t-test and ANOVA were performed using α = 0.05. Elbow flexors were stronger isometrically (P < 0.001, ES = 1.23) but weaker concentrically (P < 0.05, ES = 0.54) than extensor muscles, possibly because of the extensive grip disputes and pushing of opponents in BJJ. The T–A relationship had an inverted “U”-shape. Torque differences across elbow angles were moderate (ES = 0.62) for the extensor and large (ES = 0.92) for the flexor muscles. Isometric torque was greatest for elbow angles of 105° and 75° and smallest for 45° and 120° for extensor and flexor muscles, respectively. Elbow flexors had a greater RFD than extensors, regardless of elbow angle. The present study provides comprehensive results for elbow muscle strength in BJJ practitioners.