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Perivascular medical devices and perivascular drug delivery systems are conceived for local application around a blood vessel during open vascular surgery. These systems provide mechanical support and/or pharmacological activity for the prevention of intimal hyperplasia following vessel injury. Despite abundant reports in the literature and numerous clinical trials, no efficient perivascular treatment is available. In this review, the existing perivascular medical devices and perivascular drug delivery systems, such as polymeric gels, meshes, sheaths, wraps, matrices, and metal meshes, are jointly evaluated. The key criteria for the design of an ideal perivascular system are identified. Perivascular treatments should have mechanical specifications that ensure system localization, prolonged retention and adequate vascular constriction. From the data gathered, it appears that a drug is necessary to increase the efficacy of these systems. As such, the release kinetics of pharmacological agents should match the development of the pathology. A successful perivascular system must combine these optimized pharmacological and mechanical properties to be efficient. [ABSTRACT FROM AUTHOR]

Gastroesophageal reflux disease (GERD) is a very common condition and affects approximately 7-20% of the pediatric population. Symptoms from pathological GERD include regurgitation, irritability when feeding, respiratory problems, and substernal pain. Treatment typically starts with dietary modifications and postural changes. Antireflux medications may then be added. Indications for operative management in the pediatric population include failure of medical therapy with poor weight gain or failure to thrive, continued respiratory symptoms, and complications such as esophagitis. Laparoscopic Nissen fundoplication has become the standard of care for surgical treatment of children with GERD. The key technical aspects of laparoscopic Nissen fundoplication include creation of an adequate intra-abdominal esophagus, minimal dissection of the hiatus with exposure of the right crus to identify the gastroesophageal junction, crural repair, and creation of floppy, 360° wrap that is oriented at the 11 o׳clock position. [ABSTRACT FROM AUTHOR]

[Display omitted] • SWAT+ model and WRAP were coupled to obtain daily streamflow data. • Disaggregation technique based on flow pattern is recommended. • Disaggregation of a monthly calibrated model estimates reliable environmental flows. • SWAT+ model calibrated on a daily scale underestimates environmental flow. • An alternative for environmental flows estimation in anthropized watersheds is shown. The Water Framework Directive requires all water bodies in EU countries to ensure the ecological integrity of freshwater ecosystems in all water bodies. A "good" status in water bodies leads to their biological elements to reproduce reference conditions, so quantity and timing should be considered in describing environmental flows. However, the availability of daily natural flow data is one of the major drawbacks, especially in highly water-regulated countries, such as Spain, and hydrological models, such as the Soil and Water Assessment Tool (SWAT+) model, can be used to generate them. This work evaluated three different approaches for obtaining daily flows used to characterise the natural regime and to estimate environmental flows in the Piloña River (northern Spain) and Tagus River (centre Spain) basins: Scenario 1) daily flows simulated by the SWAT+ model calibrated on a monthly scale; Scenario 2) daily flows estimated by applying monthly-to-daily disaggregation techniques from the monthly series obtained from the SWAT+ model calibrated on a monthly scale using Water Rights Analysis Package (WRAP) software; and Scenario 3) daily flows simulated by the SWAT+ model calibrated on a daily scale. The Kling–Gupta efficiency (KGE), percent bias (PBIAS), Nash–Sutcliffe efficiency (NSE), root mean square error (RMSE) and standard deviation ratio (RSR) were used to evaluate the model's performance. Furthermore, the indicators of hydrologic alteration in rivers (IAHRIS) and the basic flow methods were assessed and compared with those obtained directly using the real data observed at the gauging station. Our results indicated that Scenario 2 outperformed the rest of the approaches for all the statistics used. KGE and NSE varied between 0.78 and 0.92 for both basins in Scenario 2 while these values decreased to 0.50–0.60 for KGE and 0.20–0.40 for NSE in Scenarios 1 and 3. Moreover, PBIAS ranged between 3.24 and 4.47% in validation periods in Scenario 2, while it decreased to −14.64% in Scenario 3. Likewise, Scenario 2 was also observed to show better performance related to both the patterns of the natural regime and the basic flow values, which were generally underestimated by the other scenarios. The methodology proposed provides a valuable tool for evaluating and managing the hydrological and environmental status of river basins. [ABSTRACT FROM AUTHOR]

Background Intimal hyperplasia (IH) remains a major cause of poor patient outcomes after surgical revascularization to treat atherosclerosis. A multitude of drugs have been shown to prevent the development of IH. Moreover, endovascular drug delivery following angioplasty and stenting has been achieved with a marked diminution in the incidence of restenosis. Despite advances in endovascular drug delivery, there is currently no clinically available method of periadventitial drug delivery suitable for open vascular reconstructions. Herein we provide an overview of the recent literature regarding innovative polymer platforms for periadventitial drug delivery in preclinical models of IH as well as insights about barriers to clinical translation. Methods A comprehensive PubMed search confined to the past 15 years was performed for studies of periadventitial drug delivery. Additional searches were performed for relevant clinical trials, patents, meeting abstracts, and awards of NIH funding. Results Most of the research involving direct periadventitial delivery without a drug carrier was published prior to 2000. Over the past 15 years there have been a surge of reports utilizing periadventitial drug-releasing polymer platforms, most commonly bioresorbable hydrogels and wraps. These methods proved to be effective for the inhibition of IH in various animal models (e.g. balloon angioplasty, wire injury, and vein graft), but very few have advanced to clinical trials. There are a number of barriers that may account for this lack of translation. Promising new approaches including the use of nanoparticles will be described. Conclusions No periadventitial drug delivery system has reached clinical application. For periadventitial delivery, polymer hydrogels, wraps, and nanoparticles exhibit overlapping and complementary properties. The ideal periadventitial delivery platform would allow for sustained drug release yet exert minimal mechanical and inflammatory stresses to the vessel wall. A clinically applicable strategy for periadventitial drug delivery would benefit thousands of patients undergoing open vascular reconstruction each year. [ABSTRACT FROM AUTHOR]

Executing a life cycle carbon analysis on a building has two components to consider: the Embodied Carbon (EC) and In-use Carbon, the sum of these forms ‘the building carbon budget'. The in-use can be obtained through regulatory tools such as the Standard Assessment Procedure (SAP) in the UK. Embodied carbon has a loose framework with little guidance on a standardised methodology. This paper explores embodied carbon analysis using building components to enhance the understanding of the sensitivity and categorisation of measurements to propose a methodology. The exploration of differing methods on a Passivhaus case study was undertaken with the use of global warming potential identified as the correct unit of measurement. Different methods of estimating quantities and datasets used for an EC calculation are discussed. Results highlight a variation in carbon emissions for certain common building materials between the method used in the Environmental Performance Declarations (EPD) compared to current databases such as Inventory of Carbon and Energy (ICE) using Cradle to Gate data. Designers prefer simple embodied carbon calculation methods. This paper identifies a calculation method giving an acceptable accuracy with the least amount of input data required to implement regulatory standardisation within the industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The purpose of this study was to assess the efficacy of absorbable mesh wrapping (MW) versus perihepatic packing (HP) for severe hepatic injury. METHODS: From January 2001 to December 2012, data were collected for MW patients with hepatic injury. Patients who underwent HP were matched with MW patients by injury mechanism, liver injury grade, Injury Severity Score, and age. RESULTS: Twenty-six MW and twenty-six HP patients were matched. Eighteen blunt and 8 penetrating injuries were present in each group. There were 9 (35%) mortalities in the MW group and 16 (62%) in the HP groups (P = .03). Average transfusions were 12.0 and 24.5 (P = .03) packed red blood cells in the MW and HP groups, respectively. Average laparotomies per survivors were 1.3 for the MW and 3.1 for the HP groups (P = .01). Average length of stay for survivors was 19 and 47 (P = .04) days in the MW and HP groups, respectively. CONCLUSION: MW for hepatic injuries can significantly decrease mortality, transfusions, laparotomies, and length of stay. [ABSTRACT FROM AUTHOR]

Summary: Background: Healthcare educators face numerous challenges including technological change, information overload, and the need to maintain clinical expertise and research knowledge across multiple specialities. Students also need to develop their capacity for critical thinking, using and discriminating between diverse sources of knowledge in order to advance their own practice. Objectives: To investigate student perceptions of the affordances of a novel web 2.0-based tool – the Web Resource Appraisal Process (WRAP), designed to support the development of critical thinking skills, and to identify how student''s understanding of critical thinking and their use of web 2.0 resources might inform the cross-disciplinary development of the WRAP. Design: A two phase, action research study of student perceptions of the WRAP and their ability to source and identify valid information sources. Settings: Implemented at the University of South Australia, development of the WRAP is an international project with the University of Westminster, UK. Participants: Students from international locations participated in the project. Methods: A mixed methods approach was adopted involving a two phase action research study. In phase one, student perceptions of the WRAP were obtained using a modified course feedback questionnaire. This informed the development of a subsequent questionnaire used to survey student perceptions of their usage of online resources, the ease of access of such resources and their approaches to determining their validity. Results: Results suggest that students mainly use traditional resources when preparing work for assessment and they either do not understand the concept of, or do not exercise, critical thinking skills in such activities. However, the feedback from students using the WRAP, demonstrated that they found it instructive and useful. Conclusions: To ensure that practice developments are based on authoritative evidence, students need to develop critical thinking skills which may be facilitated by tools such as the WRAP. [Copyright &y& Elsevier]

Abstract: This paper reports on an experimental investigation that evaluates the effectiveness of newly developed material, steel fibre reinforced polymer (SFRP) sheets to confine small-scale plain concrete circular and square columns. Different parameters were investigated including: number of SFRP layers (1, 2, and 3), target concrete compressive strength (25, 30, and 35MPa), cross-section of the columns (circular and square), and corner radius for square columns (3, 6, 10, and 25mm). The experimental investigation was conducted in three phases. In Phase I, 36 circular specimens (150mm diameter×300mm height) and in Phase II, 36 square specimens (150mm side length×300mm height) were tested. In each phase, the specimens were divided into three groups according to concrete compressive strength. In each group, three specimens were tested without wrapping for comparison purposes, and three specimens for each number of layers. In Phase III, 12 SFRP wrapped (one layer) square specimens with a target concrete compressive strength of 25MPa were tested to investigate the effect of varying the corner radii on the confined compressive strength. The specimens were tested under monotonic concentric uni-axial compression load. Results showed that SFRP confinement improved the performance of both circular and square specimens in terms of axial strength and ductility; however, the improvement for square specimens was not as prominent as that for circular specimens. Rounding the corners of the square specimens improves the situation for square specimens and performance enhances with increasing corner radius. The confined concrete compressive strength was predicted using equations available in different codes and models and compared with experimental results. [Copyright &y& Elsevier]

Abstract: The Government''s Sustainable Buildings Task Group recently recommended a benchmark requirement for a minimum 10% of reused/reclaimed or recycled content (by material value) in construction projects. The benchmark would be implemented through Building Regulations and public sector procurement. This paper presents the findings of a pilot study to inform decision-making on the feasibility of setting and meeting such a requirement. The project involved determining current levels of recycled content in Defence Estates’ standard design for modern barracks accommodation, and quantifying the scope to increase this content. The existing designs for the new barracks were found to use nearly 20% recycled and recovered materials. The project identified opportunities to increase this proportion to nearly 25% with no increase in cost or risk. [Copyright &y& Elsevier]

Abstract: Rectangular columns are often used in bridge pier design, and they make up the majority of building columns. Columns in need of strengthening and retrofit are very common. This paper presents results of a comprehensive experimental investigation on the behavior of axially loaded rectangular columns that have been strengthened with glass fibre reinforced polymer (GFRP) wrap. This paper is intended to examine several aspects related to the use of glass FRP fabrics for strengthening rectangular columns subjected to axial compression. The objectives of the study are as follows: (1) to evaluate the effectiveness of external GFRP strengthening for rectangular Concrete Columns (2) to evaluate the effect of number of GFRP layers on the ultimate load and ductility of confined concrete and (3) to evaluate the effect of the aspect ratio of the column on the effectively confined cross-section. To cover a wide range of cross-sectional dimension ratios, three aspect ratios (a/b, where a and b are, respectively, the longer and shorter sides of the cross-section) were studied: a/b =1.0, a/b =1.25, and a/b =1.66. Specimens with zero, one, and two layers of GFRP wrap were investigated. Totally nine specimens were subjected to axial compression which includes three control specimens. All the test specimens were loaded to failure in axial compression and the behavior of the specimens in the axial and transverse directions was investigated. [Copyright &y& Elsevier]