Structure and morphology of linear polyethylene extrudates induced by elongational flow

This study focuses on the structure, morphology, and properties of linear polyethylene (PE) profiles manufactured by continuous extrusion. High level of chain orientation was achieved using specific flow and processing conditions. An extrusion die with semihyperbolic convergency was used to generate high percentage of elongational flow and chain extension. Simultaneously, high extrusion pressure and relatively low melt temperature led to flow‐induced crystallization of PE extended chains. The structure of PE tapes consists of crystal aggregates with different level of orientation and crystallinity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

CSCL for intellectually disabled pupils: Stimulating interaction by using a floor control mechanism

Computer-supported collaborative learning has an unexploited potential of becoming an effective learning method for pupils with intellectual disabilities. This paper aims at showing how some specific requirements of this target group may be met by structuring a learning situation with the help of floor control, which restricts the opportunities of a learning dyad to act simultaneously within the learning environment. It was expected that floor control could improve communication between pupils with intellectual disabilities by explicitly structuring and restricting activities in the learning environment and making it necessary for the pupils to communicate. To examine if floor control really supports the collaboration process in the hypothesized way, two different versions of a CSCL environment were implemented and compared. The results revealed improved task-related communication and a higher quality of interaction outcomes.     

Changes in Older Europeans’ Health Across Two Waves of SHARE: Life-Course and Societal Determinants

Building on recent research investigating the role of life-course factors (including childhood conditions) and societal context in older Europeans health status, this study investigates the determinants of changes in elders’ health across two waves of the Survey of Health Ageing and Retirement in Europe (SHARE). Controlling for individuals’ current living conditions at baseline, our analysis provides evidence for long-term associations between childhood conditions (SES, health, cognition) and health dynamics in older age. Moreover, our findings suggest that income inequality tends to increase elders’ risk of experiencing negative health changes (decreases their chance to recover from poor health, respectively). Our study underlines the importance of accounting for both life-course and societal determinants of later life health dynamics.     

Antioxidant and antiglycation properties of Passiflora alata and Passiflora edulis extracts

The leaves of Passiflora alata Dryander and Passiflora edulis Sims, traditionally used in American countries to treat both anxiety and nervousness by folk medicine, are rich in polyphenols, which have been reported as natural antioxidants. In this study, the antioxidant activities of P. edulis and P. alata hydroalcoholic leaf extracts were verified in in vitro and ex vivo assays. P. alata showed a higher total reactive antioxidant potential than did P. edulis. The antioxidant activities of both extracts were significantly correlated with polyphenol contents. In addition, both extracts attenuated ex vivo iron-induced cell death, quantified by lactate dehydrogenase leakage, and effectively protected against protein damage induced by iron and glucose. These findings demonstrate that the P. alata and P. edulis leaf extracts have potent in vitro and ex vivo antioxidant properties and might be considered as possible new sources of natural antioxidants.     

Landmarks or surveys? The impact of different instructions on children’s performance in hierarchical menu structures

Which kind of instruction helps children aged 9–14 years interact efficiently with a mobile phone? Due to analogies between navigation in menu structures and the natural environment, three instructions providing different forms of spatial knowledge were under study: A step-by-step instruction featuring landmark knowledge of the menu functions to be selected, a diagram of the menu structure providing survey knowledge and a free exploration of the menu, also giving the children the opportunity to develop survey knowledge. Results show a superiority of the two instructions that provide survey knowledge, except for the youngest children aged 9–10 years. This group showed to have lower spatial abilities and is therefore presumably not able to understand and integrate this type of knowledge. For those very young children, the landmark information given in traditional step-by-step instructions is more helpful. It is concluded, that simple diagrams of the menu structure can help children from 11 years on to significantly ease their interaction with small menu driven devices.     

Molecular Epidemiology of Mitochondrial Cardiomyopathy: A Search Among Mitochondrial and Nuclear Genes

Mitochondrial Cardiomyopathy (MCM) is a common manifestation of multi-organ Mitochondrial Diseases (MDs), occasionally present in non-syndromic cases. Diagnosis of MCM is complex because of wide clinical and genetic heterogeneity and requires medical, laboratory, and neuroimaging investigations. Currently, the molecular screening for MCM is fundamental part of MDs management and allows achieving the definitive diagnosis. In this article, we review the current genetic knowledge associated with MDs, focusing on diagnosis of MCM and MDs showing cardiac involvement. We searched for publications on mitochondrial and nuclear genes involved in MCM, mainly focusing on genetic screening based on targeted gene panels for the molecular diagnosis of the MCM, by using Next Generation Sequencing. Here we report twelve case reports, four case-control studies, eleven retrospective studies, and two prospective studies, for a total of twenty-nine papers concerning the evaluation of cardiac manifestations in mitochondrial diseases. From the analysis of published causal mutations, we identified 130 genes to be associated with mitochondrial heart diseases. A large proportion of these genes (34.3%) encode for key proteins involved in the oxidative phosphorylation system (OXPHOS), either as directly OXPHOS subunits (22.8%), and as OXPHOS assembly factors (11.5%). Mutations in several mitochondrial tRNA genes have been also reported in multi-organ or isolated MCM (15.3%). This review highlights the main disease-genes, identified by extensive genetic analysis, which could be included as target genes in next generation panels for the molecular diagnosis of patients with clinical suspect of mitochondrial cardiomyopathies.     

Indene epoxidation over immobilized methyltrioxorhenium on MCM-41 silica,fumed silica and aluminosilicate materials

The presented report focuses on the testing of heterogenized methyltrioxorhenium (MTO) in indene epoxidation. A range of mesoporous materials with different SiO₂/Al₂O₃ ratios, namely aluminosilicates type Siral and MCM-41 silica and fumed silica, were used as supports for immobilization of MTO. The tested support materials and prepared catalytic systems exhibited high surface area, well-defined regular structure and narrow pore size distribution of mesopores and therefore represent good quality catalysts for various reactions. The immobilized MTO on various supports was tested for the preparation of 1,2-epoxyindane using two forms of hydrogen peroxide as oxidation agents, namely aqueous solution of hydrogen peroxide and its anhydrous form, urea-hydrogen peroxide. The prepared catalysts were successfully used for the preparation of 1,2-epoxyindane with achieved 100 % selectivities to the desired product at high conversions of indene.     

The Fight against the Influenza A Virus H1N1: Synthesis,Molecular Modeling,and Biological Evaluation of Benzofurazan Derivatives as Viral RNA Polymerase Inhibitors

The influenza RNA polymerase complex, which consists of the three subunits PA, PB1, and PB2, is a promising target for the development of new antiviral drugs. A large library of benzofurazan compounds was synthesized and assayed against influenza virus A/WSN/33 (H1N1). Most of the new derivatives were found to act by inhibiting the viral RNA polymerase complex through disruption of the complex formed between subunits PA and PB1. Docking studies were also performed to elucidate the binding mode of benzofurazans within the PB1 binding site in PA and to identify amino acids involved in their mechanism of action. The predicted binding pose is fully consistent with the biological data and lays the foundation for the rational development of more effective PA–PB1 inhibitors.     

Experimental‐numerical research on the seismic performance of URM buildings made of lightweight AAC blocks / Experimentell‐numerische Untersuchung zum seismischen Verhalten von unbewehrten Mauerwerksgebäuden aus Porenbetonblöcken

Masonry walls constructed with lightweight AAC blocks and thin‐layer mortar meet the increasingly strict requirements of energy efficiency and sustainability. In this sense, they represent an excellent solution for modern buildings, not only for external cladding but also as loadbearing elements. Despite the possible advantages of using lightweight AAC masonry, a specific assessment of its seismic performance is mandatory in order to set design recommendations allowing to reach safety levels consistent with those required for other masonry types complying with EN 1998 standard requirements. A comprehensive study on the seismic performance of unreinforced masonry buildings made of lightweight AAC was carried out in an integrated experimental‐numerical approach. The experimental campaign provided the necessary information to setup a reliable numerical model to be extensively used to assess the seismic performance of a number of prototype AAC masonry buildings with different characteristics, by means of both linear and nonlinear static (pushover) analysis. The results of this systematic numerical assessment were eventually used to draft design recommendations, to set parameters (behaviour factors) to be used in linear analysis and to calibrate rules for simple buildings.