Small and large scale segmental motion in polymers: Estimating cooperativity length by ordinary relaxation experiments

We derive a suitable expression for estimating the size of the cooperatively rearranging regions (CRRs) in supercooled polymer melts by fitting data worked out by ordinary relaxation experiments carried out in isothermal conditions. As an example, the average CRR size in poly(n-butyl methacrylate) in proximity to the glass transition temperature is derived from a stress relaxation experiment performed by means of an atomic force microscopy setup. Good agreement is found with results in the literature derived from measurements of temperature fluctuations (the so-called Donth method). The temperature dependence of the CRR size is explored for poly(butadiene); in this case the segmental relaxation function is derived through a novel method for the analysis of the efficiency with which free induction decay echoes are refocused in 1H NMR experiments. It is found that the CRR size increases upon cooling. The results derived from the analysis of the NMR data are found to be in satisfactory agreement with those worked out from broadband dielectric spectroscopy data in the literatur

Using rail to make urban freight distribution more sustainable

Rail is today a minimally used modality in urban freight distribution. To reap the benefits of this more sustainable transport mode a few experiences in Europe have attempted to introduce innovative freight distribution schemes where rail is used. One of such schemes uses rail for the urban penetration leg. After having been consolidated in a centre located outside the urban area, goods are transported by shuttle trains to a centre located inside the central area (the multi-modal urban distribution centre – MUDC) and there are transferred to low-pollution road vehicles to reach their final destination. Other schemes use tramways. The paper provides a review of rail-based schemes which have been introduced in European cities. An in-depth assessment is provided of the scheme based on the use of a MUDC. The case study relates to the distribution of fish food in Rome. The environmental and energy benefits obtainable from the shift from the current road-only scheme to the MUDC scheme are estimated in physical and monetary units. An estimate is provided of the maximum public contribution that would still make the scheme beneficial for society as a whole, obtained as the difference between the social costs of the road-only scheme and those of the MUDC scheme. Also, an assessment is provided of the profitability of the scheme from the operators‟ viewpoint

SAFFIRE: System for Autonomous Feature Filtering and Intelligent ROI Estimation

This work introduces a new framework, named SAFFIRE, to automatically extract a dominant recurrent image pattern from a set of image samples. Such a pattern shall be used to eliminate pose variations between samples, which is a common requirement in many computer vision and machine learning tasks. The framework is specialized here in the context of a machine vision system for automated product inspection. Here, it is customary to ask the user for the identification of an anchor pattern, to be used by the automated system to normalize data before further processing. Yet, this is a very sensitive operation which is intrinsically subjective and requires high expertise. Hereto, SAFFIRE provides a unique and disruptive framework for unsupervised identification of an optimal anchor pattern in a way which is fully transparent to the user. SAFFIRE is thoroughly validated on several realistic case studies for a machine vision inspection pipeline.Comment: 14 pages, 23 figures, 2 table

What determines the complication rate in high-risk chronic obstructive pulmonary disease patients: surgery or pulmonary function?

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Method for estimating the cooperativity length in polymers

The problem of estimating the size of the cooperatively rearranging regions (CRRs) in supercooled polymeric melts from an analysis of the α-process in ordinary relaxation experiments is addressed. The mechanism whereby a CRR changes its configuration is viewed as consisting of two distinct steps: a reduced number of monomers reaches initially an activated state, allowing for some local rearrangement; then, the subsequent regression of the energy fluctuation may take place through the configurational degrees of freedom, thus allowing for further rearrangements on larger length scales. The latter are indeed those to which the well-known Donth's scheme refers. Local readjustments are described in the framework of a canonical formalism on a stationary ensemble of small-scale regions, distributed over all possible energy thresholds for rearrangement. Large-scale configurational changes, instead, are described as spontaneous processes. Two main regimes are envisaged, depending on whether the role played by the configurational degrees of freedom in the regression of the energy fluctuation is significant or not. It is argued that the latter case is related to the occurrence of an Arrhenian dependence of the central relaxation rate. Consistency with Donth's scheme is demonstrated, and data from the literature confirm the agreement of the two methods of analysis when configurational degrees of freedom are relevant for the fluctuation regression. Poly(n-butyl methacrylate) is chosen in order to show how CRR size and temperature fluctuations at rearrangement can be estimated from stress relaxation experiments carried out by means of an atomic force microscopy setup. Cases in which the configurational pathway for regression is significantly hindered are considered. Relaxation in poly(dimethyl siloxane) confined in nanopores is taken as an example to suggest how a more complete view of the effects of configurational constraints would be possible if direct measurements of temperature fluctuations were combined with the proposed analysis

Legal implications of translational promises of unproven stem cell therapy

The promise stem cell therapy holds for curing diseases for which no therapy currently exists is often translated as fact. Unfortunately, enforced misconceptions between fact and promise often also translate into exploitation and harming of patients. This article aims to clear up misconceptions about the biological promise and legal consequences of insisting on promises not based on scientific facts.The Medical Research Council of South Africa in terms of the MRC’s Flagships Awards Project SAMRC-RFA-UFSP-01-2013/ STEM CELLS.http://www.sajbl.org.zaam201

Legal implications of translational promises of unproven stem cell therapy

The promise stem cell therapy holds for curing diseases for which no therapy currently exists is often translated as fact. Unfortunately, enforced misconceptions between fact and promise often also translate into exploitation and harming of patients. This article aims to clear up misconceptions about the biological promise and legal consequences of insisting on promises not based on scientific facts.The Medical Research Council of South Africa in terms of the MRC’s Flagships Awards Project SAMRC-RFA-UFSP-01-2013/ STEM CELLS.http://www.sajbl.org.zaam201

Legal implications of translational promises of unproven stem cell therapy

The promise stem cell therapy holds for curing diseases for which no therapy currently exists is often translated as fact. Unfortunately, enforced misconceptions between fact and promise often also translate into exploitation and harming of patients. This article aims to clear up misconceptions about the biological promise and legal consequences of insisting on promises not based on scientific facts.The Medical Research Council of South Africa in terms of the MRC’s Flagships Awards Project SAMRC-RFA-UFSP-01-2013/ STEM CELLS.http://www.sajbl.org.zaam201

Migration in EU Rural Areas

This report provides a quantitative overview of migration in rural areas for the entire EU. It includes a description of socio demographic characteristics and main indicators of integration of migrants living in rural areas and employed in EU agriculture. More geographically detailed analyses for Spain and Italy explore patterns of concentration of migrants in specific Local Administrative Units in relation to local characteristics of agriculture. Finally, the last chapter describes how the salience of and attitudes towards immigration differ when considering respondents living in cities, medium and small size towns, and rural areas. Overall, the report contributes to raise awareness on the poorly studied phenomenon of migration in rural areas. Migrants living in rural areas and working in agriculture, despite representing a relatively small group if compared to migrants in cities, have a fundamental role in sustaining certain types of agricultural production in constant demand of temporary work. At the same time, they tend to fair worse for most indicators of integration not only in respect of natives but also in respect of migrants living in cities and towns. Given these characteristics, migrants in rural areas would deserve special attention when designing integration policies.JRC.E.6 - Demography, Migration and Governanc