Search

Marine pollution due to spillage of hydrocarbons represents a well-known current environmental problem. In order to recover the otherwise wasted oils and to prevent pollution damage, polyurethane foams are considered suitable materials for their ability to separate oils from sea-water and for their reusability. In this work we studied polyurethane foams filled with carbon nanofibers, in varying amounts, aimed at enhancing the selectivity of the material towards the oils and at improving the mechanical durability of the foam. Polyurethane-based foams were experimentally characterized by morphological, surface, and mechanical analyses (optical microscopy observation, contact angle measurement, absorption test according to ASTM F726-99 standard and compression fatigue tests according to ISO 24999 standard). Results indicated an increase in hydrophobic behavior and a good oleophilic character of the composite sponges besides an improved selective absorption of the foam toward oils in mixed water/oil media. The optimal filler amount was found to be around 1 wt% for the homogeneous distribution inside the polymeric foam. Finally, the fatigue test results showed an improvement of the mechanical properties of the foam with the growing carbon filler amount.

The studied sensor consists of a microstrip interdigital capacitor covered by a gas sensing layer made of titanium dioxide (TiO 2 ). To explore the gas sensing properties of the developed sensor, oxygen detection is considered as a case study. The sensor is electrically characterized using the complex scattering parameters measured with a vector network analyzer (VNA). The experimental investigation is performed over a frequency range of 1.5 GHz to 2.9 GHz by placing the sensor inside a polytetrafluoroethylene (PTFE) test chamber with a binary gas mixture composed of oxygen and nitrogen. The frequency-dependent response of the sensor is investigated in detail and further modelled using an artificial neural network (ANN) approach. The proposed modelling procedure allows mimicking the measured sensor performance over the whole range of oxygen concentration, going from 0% to 100%, and predicting the behavior of the resonant frequencies that can be used as sensing parameters.

Cities are currently engaged through their urban policies in pushing people towards less environmentally impacting mobility modalities: therefore, cycling and walking are strongly promoted, especially by means of new and wider limited traffic and no-cars zones. In this paper, the effectiveness of the new smartphones and apps-based technologies in modifying the mobility behaviors of citizens towards more sustainable choices has been investigated. Specifically, the potential of a smartphone app, directly involving citizens by means of a game rewarding the most sustainable trips, has been tested on a university commuters' group. These latter, starting from their current mobility situation, were challenged by an enhanced scenario characterized by more restrictive and sustainable targets. Promising results have been obtained suggesting that game-based tools could be effectively used as urban policy interventions intended to obtain a more sustainable mobility., (© 2020 Published by Elsevier Ltd.)

The Internet of Things (IoT) refers to the interconnection of smart devices to collect data and make intelligent decisions. However, a lack of intrinsic security measures makes IoT vulnerable to privacy and security threats. With its "security by design," Blockchain (BC) can help in addressing major security requirements in IoT. BC capabilities like immutability, transparency, auditability, data encryption and operational resilience can help solve most architectural shortcomings of IoT. This article presents a comprehensive survey on BC and IoT integration. The objective of this paper is to analyze the current research trends on the usage of BC-related approaches and technologies in an IoT context. This paper presents the following novelties, with respect to related work: (i) it covers different application domains, organizing the available literature according to this categorization, (ii) it introduces two usage patterns, i.e., device manipulation and data management (open marketplace solution), and (iii) it reports on the development level of some of the presented solutions. We also analyze the main challenges faced by the research community in the smooth integration of BC and IoT, and point out the main open issues and future research directions. Last but not least, we also present a survey about novel uses of BC in the machine economy.

The complex interactions between human behaviors and social economic sciences is critically analyzed in this paper in view of possible applications of mathematical modeling as an attainable interdisciplinary approach to understand and simulate the aforementioned dynamics. The quest is developed along three steps: Firstly an overall analysis of social and economic sciences indicates the main requirements that a contribution of mathematical modeling should bring to these sciences; subsequently the focus moves to an overview of mathematical tools and to the selection of those which appear, according to the authors bias, appropriate to the modeling; finally, a survey of applications is presented looking ahead to research perspectives., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Iridescent organic films consisting of quasi-parallel wire-like microstructures are grown by castings from ethanol solutions containing mixtures of aluminium-tris-hydroxyquinoline and 1,10-phenanthroline. Spectrophotometric measurements carried out in the ultraviolet-visible range indicate that the microstructured films have angular-dependent optical behaviour, which is motivated by a refractive-index modulation over dimensions that are comparable to visible-light wavelengths. According to the results of investigations carried out by means of optical microscopy, atomic force microscopy (AFM), and scanning near-field optical microscopy (SNOM), the refractive-index modulation originates from a thickness modulation and a phase separation that occurs as the aluminium-tris-hydroxyquinoline and phenanthroline co-crystallize, with the former material being arranged to form a green luminescent pattern on the top of the latter one.

Lack of insight or impaired awareness of deficits in patients with dementia is a relatively neglected area of study. The aim of this study was to evaluate insight in a group of demented patients with two assessment scales and to assess their relationship with the cognitive level of disease severity. Sixty-nine consecutive patients affected by Alzheimer's disease (n = 37) and vascular dementia (n = 32) with a wide range of cognitive impairment (MMSE = 17.0 +/- 6.4) were recruited. Insight was evaluated with the Guidelines for the Rating of Awareness Deficits (GRAD)--specifically targeted to memory deficits--and the Clinical Insight Rating scale (CIR), evaluating a broader spectrum of insight (reason for the visit, cognitive deficits, functional deficits, and perception of the progression of the disease). In the whole sample, GRAD and CIR were significantly associated with MMSE (Spearman's coefficient = .51, p < .001; and r = -.55, p < .001) and with Clinical Dementia Rating scale (-.57, p < .001; and r = .57, p < .001) respectively. The shape of the relationship of MMSE with CIR and GRAD scales was assessed with spline smoothers suggesting that the relationship follows a trilinear pattern and is similar for both scales. Insight was uniformly high for MMSE scores > or = 24, showed a linear decrease between MMSE scores of 23 and 13, and was uniformly low for MMSE scores < or = 12. The trilinear model of the association between insight and cognitive status reflects more closely the observable decline of insight and can provide estimates of when the decline of insight begins and ends.

Objective: To determine the level of agreement between the primary caregiver's report on patient activities of daily living (ADLs) and ADLs assessed directly in a sample of patients affected by very mild and mild dementia and to assess whether this agreement is influenced by the caregiver's depressive symptoms and burden., Patients and Methods: Data were obtained from the baseline sample of the Mild Dementia Longitudinal Study, consisting of 111 consecutive patients affected by dementia with very mild to mild functional impairment (grades .5 and 1 on the Clinical Dementia Rating Scale). As is usual for patients referred to our Alzheimer's Unit, anamnestic, cognitive, functional and behavioral information are collected from the primary caregiver. Along with sociodemographic characteristics, caregivers' depressive symptoms (Beck Depression Inventory Scale) and burden (Nowak and Guest's Caregiver Burden Inventory Scale) were also evaluated. Patients underwent a performance-based assessment of the activities of daily living (DAFS) and direct assessment of physical function with the Physical Performance Test (PPT). Caregiver's report and direct observation have been compared for the following ADLs: dressing, toileting, walking, telephone use, shopping, and money use. Discriminant analyses were conducted to examine the degree of agreement between caregiver-report functional status and performance-based measures and whether additional agreement is attributable to caregiver's burden and depressive symptoms., Results: The strength of the association between the caregiver's report and performance-based measures of ADLs is high for motor performance (walking), moderate to good for dressing, but only moderate for telephone, money use, and shopping. No association was found for toileting. The discrepancies between caregiver report and performance-based assessment were influenced substantially by the burden caused by demands and restrictions on a caregiver's time., Conclusions: With the exception of motor performance (walking), the caregiver's report and the performance-based assessment of functional status measure different aspects of a patient's functional status. Contrasts between the caregiver's report and observed ADL performance in mildly and very mildly demented patients are influenced by the caregiver's burden.

Objective: to assess the validity of the Direct Assessment of Functional Status (DAFS) performance-based functional scale for the staging of dementia severity by comparing it with established clinical, functional and cognitive scales., Patients and Methods: 93 consecutive Alzheimer's disease patients underwent DAFS. Socio-demographic variables, cognitive status (Mini-Mental State Examination; MMSE), global disease severity (Clinical Dementia Rating; CDR), disease duration, physical performance (Physical Performance Test, PPT) and functional status (as reported by the primary caregiver) were also recorded and basic (B) and instrumental (I) activities of daily living (ADL) assessed., Results: a significant correlation was found between DAFS and MMSE (Pearson's r = 0.60; P < 0.01), PPT (r = 0.54; P < 0.01) and CDR (Spearman correlation coefficient: -0.48; P < 0.01). A mild, significant correlation was found between DAFS score and daily function as reported by the primary caregiver (r = -0.30 for BADL and r = - 0.27 for IADL). On multiple regression analysis, only MMSE and PPT were independently associated with the DAFS score, explaining 56% of DAFS total variance. ADL scales did not independently contribute to DAFS variance. A multivariate regression model of the association of DAFS with CDR showed that the association was significant even after adjustment for MMSE and PET, suggesting that DAFS scores provide additional information on dementia severity., Conclusion: DAFS is a valid tool for the assessment of dementia severity, capturing cognitive and physical aspects of disability.

Unlike conventional antidepressants, rolipram stimulates both the presynaptic as well as the postsynaptic component of monoaminergic transmission. Several double-blind comparative trials are on the way to assess the clinical efficacy and safety of this novel compound. The present study was a randomized double-blind double-dummy comparison with imipramine in inpatients with major, "minor" and atypical depressions (DSM III). Results show no relevant differences between rolipram and imipramine regarding efficacy and safety.