Chemical analyses of ancient glass findings excavated in the Venetian lagoon

Although Venice is regarded as being one of the most important centres of glass manufacture and trade in Western Europe, little is known about the origins of the Venetian glassmaking. Some archaeologists suggest there is a continuity in the history of glass making, in its transplantation from the Roman centres of the mainland (Altino and Aquileia), first to some islands of the lagoon, and later to the town. Some others, instead, think that there was no continuity at all and that the art of glassmaking was imported in Venice from the Islamic glass factories of the Middle East. Of great help in answering this and other technological questions is the information about the composition of ancient glass from well-dated excavations that allows to conclude on the early technology, sources of raw materials and long-distance trade. Some significant glass findings, including fragments of pots used for glass melting, were found on the island of Torcello and, more recently, in two emergency excavations in the historic centre of Venice. In this paper, the chemical composition of a large set of glass findings (and related materials) from the Venetian lagoon dating from the 7th to the 13th centuries is determined by X-ray microanalysis in order to throw new light on the glassmaking technology in the early centuries of the Venetian tradition. The results show that in this period there occurred a gradual transition from the Roman technique (a two-ingredient formulation with silica-lime sand and natron as a fluxer), towards the use of silica sand and soda plant ash. There is evidence, therefore, for a production continuity with the Roman period (melting pots and glass scraps with a natron-based composition), yet restricted to transparent blown items. No evidence was found for a local production of glass tesserae for the mosaics of the church of St. Maria Assunta in Torcello.     

High School Internships: Utilizing a Community Cultural Wealth Framework to Support Career Preparation and College-Going Among Low-Income Students of Color

This article investigates the experience of 229 low-income students of color who participated in an innovative high school internship program between 2011 and 2015. Using mixed methods (interviews, observations, and survey), the authors aim to understand the types of knowledge, information, and supports these students develop and expand in relation to careers and the college-going process. The authors draw on students' community cultural wealth to highlight the way the internship program supports students' aspirational, navigational, linguistic, resistant, and social capital.     

Developing capabilities in new ventures: a knowledge management approach

On the basis of a knowledge management perspective, this paper expands the literature on new ventures’ capabilities by considering how these firms fill knowledge gaps and develop the technological, marketing, management, and ICT capabilities they need to compete. In particular, this paper investigates the role of networks in these dynamics. Although new technology-based firms have great potential to introduce innovative products into the market, they might suffer from more critical knowledge gaps and capability weaknesses than established firms. The results of a quantitative investigation of an original data set of more than 400 Italian new ventures specializing in high-tech industries show that these firms acquire knowledge to support their capability growth mainly through the management of intense relations with multiple external sources of knowledge. In addition, capability development is supported by the variety of founders’ industry experience and the presence of young graduates among the founding team.     

Comparing Collective and Personal Professional Theories of Experienced Practitioners

A characteristic of being a professional is the internalisation of the collective professional theory (CPT)—the shared insights of professionals. Problems arise when different opinions stemming from professionals’ personal professional theories (PPTs) obscure a CPT’s content. This study argues that cooperating professionals’ CPTs form a so-called field and can be represented by concept maps. The relations between PPTs, CPTs, and fields are examined for the fields of accountancy and teaching. The results indicate that CPTs are more complex than PPTs, and that the teachers’ field is more diverse than the accountants’ field. These insights are important because socialisation in a field may be fostered if one is aware of CPTs and the surrounding field in relation to one’s PPT.     

Cultural capital and educational strategies. Shaping boundaries between groups of students with homologous cultural behaviours

Rather than assessing its causal effect on educational attainment, the authors of this article aim to use the concept of cultural capital to define a huge, complex and interconnected collection of educational and school strategies adopted by students and families and to examine the way that these strategies are related to school inequalities. Data analysed come from the 2009 Italian survey for the Program for International Student Assessment run by the OECD. A Latent Class Regression Analysis has been applied to categorize four groups of individuals who share specific cultural habits, educational dispositions and choices, and social status; in short, the four groups differentiate individuals with a different endowment of the intangible asset, cultural capital. Moreover, using the socio-economic status as a covariate we link the latent class membership probability with individuals’ social standing and, consequently school choices.     

Effect of resistance training with different frequencies and subsequent detraining on muscle mass and appendicular lean soft tissue,IGF-1, and testosterone in older women

Objective: To analyse the effect of resistance training (RT) frequency on muscle mass, appendicular lean soft tissue, insulin-like growth factor 1 (IGF-1), testosterone, and their changes with detraining in older women. Methods: Forty-five physically independent older women (≥ 60?years) were randomly assigned to perform RT either two (G2X, n = 21) or three times/week (G3X, n = 24), during 12?weeks (8 exercises, 1 set of 10–15 repetition maximum). Muscle mass and appendicular lean soft tissue, IGF-1, testosterone, and dietary intake were measured at pre-training, post-training, and after detraining (12?weeks). Results: Muscle mass and appendicular lean soft tissue significantly increased post-training (G2X?=?+5.5% and G3X?=?+5.8%, P?P?P?Conclusion: We conclude that lower RT frequency is as effective as higher frequency to improve muscle mass and appendicular lean soft tissue, and to maintain testosterone and IGF-1. Additionally, detraining may reduce testosterone regardless of RT frequency. These results are specifically for community-dwelling older women and may not be generalized to other populations.     

What is the ‘Social’ in Climate Change Research? A Case Study on Scientific Representations from Chile

Over the last few decades climate change has been gaining importance in international scientific and political debates. However, the social sciences, especially in Latin America, have only lately become interested in the subject and their approach is still vague. Scientific understanding of global environmental change and the process of designing public policies to face them are characterized by their complexity as well as by epistemic and normative uncertainties. This makes it necessary to problematize the way in which research efforts understand ‘the social’ of climate change. How do ‘the climate’ and ‘the social’ interpenetrate as scientific objects? What does the resulting field look like? Is the combination capable of promoting reflexivity and collaboration on the issue, or does it merely become dispersed with diffuse boundaries? Our paper seeks to answer these and other related questions using Chile as a case study and examining peer-reviewed scientific research on the topic. By combining in-depth qualitative content analysis of each paper with a statistical meta-analysis, we were able to: characterize the key content and forms of such literature; identify divisions and patterns within it; and, discuss some factors and trends that may help explain these. We conclude that the literature displays two competing trends: while it is inclined to become fragmented beyond the scope of the ‘mitigation’ black box, it also tends to cluster along the lines of methodological distinctions traditionally contested within the social sciences. This, in turn, highlights the persistence of disciplinary divisions within an allegedly interdisciplinary field.

     

Analysis of the distances covered and technical actions performed by professional tennis players during official matches

The purpose of this study was to analyse the physical and technical performances of professional tennis players during official matches. The trajectories of eight players were obtained during matches, using an automatic tracking method. The distances covered and technical performances were analysed for the first and second sets. The athletes covered (mean ± standard deviation) a total of 1702.4 ± 448.2 m in the first set, 1457.6 ± 678.1 m in the second set and 3160.0 ± 880.1 in the entire match. No differences were found between the sets for the physical variables (lateral and forward displacements, distance covered per rally, per game and per set, and the percentage of time spent in each range of velocity). However, the distances covered by the athletes during the rallies in which they were serving (median = 5.2; interquartile range (IQR) = 6.7 m) were statistically smaller than when they were returning (median = 6.2; IQR = 7.7 m). Forehand ground stroke proficiency decreased from the first (mean ± standard deviation: 75.2 ± 4.11%) to the second set (mean ± standard deviation = 65.5 ± 14.3%). In conclusion, tennis players did not present reduced physical performance from the first to the second set.