Chemical air filtration in archives and libraries reconsidered

The implementation of chemical filtration in air-conditioning systems in archive and library repositories has become standard practice for heritage institutions in many countries. This practice is codified in official standards with general reference to a substantial body of scientific publications on the effects of air pollutants on paper materials. In this paper we report the application of a well-established decision analysis approach elaborating an integral cost-benefit perspective to provide decision support to four European national heritage institutions confronted with dilemmas in connection to chemical air filtration. Available scientific evidence for air pollution induced damage of paper material is reviewed and weighed against financial and environmental costs of air pollution control. Exposure of paper to both indoor and outdoor generated air pollutants at typical concentration levels observed within storage areas is expected to cause minimal to no additional yellowing and embrittlement, while the costs of chemical air filtration are significant. From a cost-benefit perspective the use of chemical air filtration in typical library and archive repositories is therefore discouraged.     

The terracotta modelli of Palazzo Venezia in Rome: Investigation of the constituent materials for fundamental knowledge and to aid conservation decisions

This work presents the results of the investigation carried out on a group of terracotta sculptures (modelli) (sixteenth to eighteenth century) belonging to the extraordinary collection of Palazzo Venezia in Rome. The study, the diagnostic analysis, and the conservation work, were possible thanks to the grant supplied by the Getty Foundation of Los Angeles and by the bank Intesa San Paolo. The terracotta modelli had a practical function as they were of great use as sketches to the creation of the final masterpieces or as models for restoration. As a consequence, the terracotta models allow reconstructing the creative process of artists and restorers, fundamental to outlining the ancient workshop production. X-ray fluorescence spectroscopy, micro-stratigraphic investigation, Fourier transform infrared spectroscopy, and micro-Raman spectroscopy were chosen as useful techniques to study the morphology and composition of the surface-painted layers. Usually the surfaces were painted in order to simulate the materials of the sculpture for which the model was created, for example lead white was used to obtain a white surface simulating marble. But, often the models were re-painted to make them more attractive for the antique trade. So, several pigments have been found on the surfaces such as zinc white, Prussian blue, chrome yellow, and mono-azo pigment. In some cases, the characterization of the surface paintings was particularly important to the final decision about removing or leaving the surface paint in place.     

Changeover from unsignaled to signaled avoidance with and without a feedback stimulus in rats

Two experiments are reported in which, by pressing a lever, unsignaled avoidable shocks could be changed to signaled avoidable shocks for periods of 1 min, after which unsignaled avoidance was automatically reinstated. A correlated stimulus identified the signaled schedule. Under these conditions, Ss changed over at a rate sufficient to remain in the signaled schedule more than 90% of the time. Both experiments showed that changeover performance was under the control of the correlated stimulus. Presenting the signaled schedule without the correlated stimulus did not maintain changing over. The second experiment showed that a 1-sec presentation of the correlated stimulus was sufficient to maintain changeover performance. The results were attributed to the conditioned reinforcing properties of the correlated stimulus.     

Measuring the academic reputation through citation networks via PageRank

The objective assessment of the prestige of an academic institution is a difficult and hotly debated task. In the last few years, different types of university rankings have been proposed to quantify it, yet the debate on what rankings are exactly measuring is enduring.To address the issue we have measured a quantitative and reliable proxy of the academic reputation of a given institution and compared our findings with well-established impact indicators and academic rankings. Specifically, we study citation patterns among universities in five different Web of Science Subject Categories and use the PageRank algorithm on the five resulting citation networks. The rationale behind our work is that scientific citations are driven by the reputation of the reference so that the PageRank algorithm is expected to yield a rank which reflects the reputation of an academic institution in a specific field. Given the volume of the data analysed, our findings are statistically sound and less prone to bias, than, for instance, ad–hoc surveys often employed by ranking bodies in order to attain similar outcomes. The approach proposed in our paper may contribute to enhance ranking methodologies, by reconciling the qualitative evaluation of academic prestige with its quantitative measurements via publication impact.     

Topic Knowledge,Text Coherence,and Interest: How They Interact in Learning From Instructional Texts

The effects of topic knowledge, text coherence, and topic interest on learning from text were examined. One hundred sixty high school students participated in 1 of 4 groups according to their levels of topic knowledge and interest. Participants read 1 of 3 versions of a scientific text: minimally coherent, locally coherent, and locally and globally coherent. Text comprehension was examined by tasks aimed at tapping both textbase and situation-model levels. The contribution of topic interest seemed to increase according to the quantity of learners' topic knowledge. High-knowledge and high-interest students performed significantly better than those in the other 3 groups in all tasks. Text version differentiated students' performance on all measures but 1. The expected Group x Version interactions did not emerge.     

Only one way to skin a cat? Heterogeneity and equifinality in European national innovation systems

One of the most significant results of the qualitative literature on national systems of innovation (NSIs) is that different systemic arrangements (i.e. configurations of actors and institutions) can deliver similar levels of innovative performance. Using factor analysis on a novel dataset of 29 quantitative indicators of innovative activities we provide an empirical characterization of the structure of European NSIs over the last ten years. Our results cast doubt on the empirical significance of the “equifinality” of heterogeneous systemic arrangements in the context of NSI. Innovation systems show inherent complexity, which leads to a high level of complementarity among their constituent components and configuration. This result implies that successful innovation policies should be systemic, leaving little flexibility in policy design and scope.     

R&D, higher education and regional growth: Uneven linkages among European regions

This paper examines the relationship between the economic growth of European regions and their knowledge and human capital endowments. The share of adult population with tertiary education and the intensity of R&D expenditures in value-added emerge as the most effective factors enhancing the growth of GDP per capita recorded, during 1995–2002, by the regions belonging to twelve countries of the former EU15. However, while the educational variable is effective for the whole regional set, the impact of R&D is significant only for the regions that are above a given threshold of per capita GDP. Moreover, remarkable disparities arise among the regions of different countries. In particular, only within North European countries there is a significant relationship between regional growth and the intensity of R&D and higher education. The policy implications of both findings are discussed.     

The Representation of Virtual Reality in Education

Students' opinions about the opportunities and the implications of VR in instruction were investigated by administering a questionnaire to humanities and engineering undergraduates. The questionnaire invited participants to rate a series of statements concerning motivation and emotion, skills, cognitive styles, benefits and learning outcomes associated with the use of VR in education. The representation which emerged was internally consistent and articulated into specific dimensions. It was not affected by gender, by the previous use of VR software, or by the knowledge of the main topics concerning the introduction of IT in instruction. Also the direct participation in a training session based on an immersive VR experience did not influence such a representation, which was partially modulated by the kind of course attended by students.     

Stabilizing two-dimensional stochastic systems through sliding mode control

This paper presents a stabilizing control for two-dimensional stochastic differential equations. The stability concept in this study is the stability in probability. To ensure such a stability, the control is designed based on the sliding mode technique, and applied to account stochastic systems. This finding has a practical implication—the proposed control can be used to stabilize a real-time automotive electronic throttle valve. The proposed approach is verified by data collected from experiments.     

Acute effects of two different tennis sessions on dorsal and lumbar spine of adult players

The aim of the study was to evaluate the dorsal and lumbar spine of expert and recreational tennis players before (pre) and after (post) two different training sessions. The sample consisted of 17 male tennis players, nine expert and eight recreational males (age 21.2 ± 1.6 years). We assessed the back surface by rasterstereography pre and post two different training sessions both lasting 1.5 h: a standard training and a specific over-shoulder shots training session, respectively. Lordotic and kyphotic angle, length, imbalance, inclination for trunk, pelvic torsion, left and right lateral deviation and surface rotation were measured. Tennis expertise (expert versus recreational) significantly affected the surface rotation and right lateral deviation (P < 0.05). Trunk length was affected by intervention (pre versus post) (P < 0.05). Left lateral deviation differed both for type of session (session 1 versus session 2) and intervention (P < 0.001, P < 0.05). Expert tennis players had higher values on surface rotation and right lateral deviation, around or just above physiological values (0–5° and 0–5 mm, respectively). Type of session significantly affected left lateral deviation, indicating that over-shoulder shots lead to a higher stress for the spine; the workload produced by both single sessions led to a shortening effect on trunk length. A single training session can induce acute modifications in some parameters of dorsal and lumbar spine of players.