Nanocomposite Microcontainers with High Ultrasound Sensitivity

A water suspension of nanocomposite microcapsules with embedded ZnO nanoparticles in the capsule shell is reported. The microcapsule morphology is characterized by confocal microscopy, TEM, SEM, and AFM before and after ultrasound treatment. A remarkably high capsule sensitivity to ultrasound is evidenced, and it is observed to grow with increasing number of ZnO nanoparticle layers in the nanocomposite shell. This effect is correlated with the mechanical properties of microcapsules measured with AFM.     

Structural,Electrical, Mechanical,and Thermal Properties of Electrospun Poly(lactic acid)/Polyaniline Blend Fibers

Conducting electrospun fiber mats based on PLA and PAni blends were obtained with average diameter values between 87 and 1 006 nm with PAni quantities from 0 to 5.6 wt.‐%. Structural characteristics of fiber mats were compared to cast films with the same amount of PAni and studied by SEM, SAXS, and AFM. Thermal properties of fiber mats and cast films were compared by DSC analyses. Mechanical properties of fiber mats were also evaluated. It was found that electrospinning process governs the crystal structure of the fibers and strongly affects fiber properties. New properties of PLA/PAni blends are reported due to the size fiber reduction.

     

Cover Image,Volume 141, Issue 17

The cover image by Lizandra Viana Maurat da Rocha highlights one of our innovative biodegradable films, which incorporated molybdenum trioxide and zinc oxide into the poly(butylene adipate-co-terephthalate) matrix through casting. The photo emphasizes its partial transparency and homogeneity. Some analytical results reported as FTIR, TD-NMR, XRD and TGA validates nanomaterial's exceptional mechanical and chemical properties. Icons below underscore its potential as an eco-friendly food packaging,with bacteriostatic features and no formation of microplastics after disposal. DOI: 10.1002/app.55294

     

Influence of ageing time on the quality of yearling calf meat under vacuum

The objective of this study is to determine the effect of the ageing time on the quality characteristics of yearling calf meat under vacuum. Ninety-six Rubia Gallega yearling calves were used. Samples of the Longissimus thoracis at 1 day post slaughter as a control, and vacuum-packaged for 7, 14 and 21 days were analysed. Colour (lightness, L*, redness, a*, yellowness, b*, hue, H^o, chroma, C*, and pigment concentration), water-holding capacity (expressible juice and cooking losses), pH and toughness were measured. The statistical analysis showed an increase in a*, b*, H^o and C* and a decrease in expressible juice, cooking losses and toughness as the ageing time increased. Discriminant analysis divided the samples into two groups; i.e., 1-day post-slaughter samples and vacuum-packaged samples. Considering vacuum-packaged samples only, canonical discriminant analysis separated the long-ageing samples (21 days) from the short-ageing samples (7 days).     

Pulsed light for the inactivation of fungal biofilms of clinically important pathogenic Candida species

Microorganisms are naturally found as biofilm communities more than planktonic free‐floating cells; however, planktonic culture remains the current model for microbiological studies, such as disinfection techniques. The presence of fungal biofilms in the clinical setting has a negative impact on patient mortality, as Candida biofilms have proved to be resistant to biocides in numerous in vitro studies; however, there is limited information on the effect of pulsed light on sessile communities. Here we report on the use of pulsed UV light for the effective inactivation of clinically relevant Candida species. Fungal biofilms were grown by use of a CDC reactor on clinically relevant surfaces. Following a maximal 72 h formation period, the densely populated biofilms were exposed to pulsed light at varying fluences to determine biofilm sensitivity to pulsed‐light inactivation. The results were then compared to planktonic cell inactivation. High levels of inactivation of C. albicans and C. parapsilosis biofilms were achieved with pulsed light for both 48 and 72 h biofilm structures. The findings suggest that pulsed light has the potential to provide a means of surface decontamination, subsequently reducing the risk of infection to patients. The research described herein deals with an important aspect of disease prevention and public health.     

Foot-turistic multimedia: designing interactive multimedia installations for shoe shops

The amount of money spent in a store is positively correlated with the amount of time spent inside. We argue this is an opportunity for multimedia installations that can entertain shoppers and promote interaction with the shop??s products. This was the main principle behind our design idea for two interactive installations specifically conceived for shoe shops. We present two applications of interactive multimedia to shoe shopping: an interactive semantic mirror and an interactive window logo. We also describe the results of ethnographic studies, before and after the design process. Our contribution is two-fold: (i) we develop and apply a new multimedia architecture that combines RFID in-store technology with high-end motion detection algorithms, and (ii) we describe one of the first few studies about multimedia installations for improving the shoe shopping experience, in what we call ??foot-turistic?? interactions.     

Preparation of composites of laponite with alginate and alginic acid polysaccharides

Polymer/clay composites have several uses in fields such as engineering, agriculture, ceramics, surface coatings, absorbent materials, pharmaceuticals or catalysis. Polysaccharides, such as alginate and its acid derivatives, are biocompatible and biodegradable polymers, effective in the production of adsorbent systems, for encapsulation and controlled release of active ingredients such as drugs and fertilizers. In this work, alginate polysaccharide and alginic acid were used to form composites with laponite, both with the original clay or with clay previously functionalized with 3‐aminopropyltriethoxysilane. The properties of the composites prepared from laponite or functionalized laponite and alginic acid or alginate were compared. The interaction of laponite with alginic acid leads to composites with strong disorder in the clay structure. In all cases, composites with high contents of polysaccharides, with good thermal and mechanical properties, are obtained. Laponite‐derived composites showed high adsorption capability for Cr(III) and methylene blue from aqueous medium. Copyright © 2012 Society of Chemical Industry     

The vulnerability of hydroelectric generation in the Northeast of Brazil: The environmental and business risks for CHESF

The main objective of this study is to identify how global climate change may affect the internal and external variables of enterprises, and how strategic planning could include responses to potential performance threats. A case study was prepared using data from the São Francisco Hydroelectric Company (CHESF), the largest hydroelectric power generator in Brazil's Northeast region. It is essential to understand how the leading energy company in the region is preparing to address these problems involving economic impacts resulting from the environmental effects of climate change. Two prospective methodologies were used to select the variables and construct a SWOT matrix, and their respective scenarios: A Panel of Experts and the Delphi Method. The methodologies used allow for four (4) distinct scenarios to be inferred for CHESF up until 2050: Development, Growth, Survival and Decline. The analyses of these scenarios concluded that CHESF's main risk from climate change is the possible reduction of water flow and reservoir levels, which could threaten energy security throughout the country if certain preventative adaptations to climate change are not implemented.     

Assessment of personal hygiene and practices of food handlers in municipal public schools of Natal,Brazil

The aim of this study was to assess the hygiene practices of food handlers in municipal schools of Natal, Brazil, where 27 public schools were evaluated, using a checklist and microbiological analysis of hands. It was found that 74.1% of the handlers did not receive periodic training, 51.9% did not undergo annual health examinations and 100% did not practice proper hand hygiene, a situation that reflected significantly (p < 0.05) in hand contamination, in which fecal coliforms were detected on 55.6% of the hands analyzed. It was concluded that the schools studied did not have appropriate hygienic conditions, suggesting the need for interventions that ensure the quality of school food served to the children.