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Circumferential wrapping of fiber-reinforced polymer (FRP) sheets is one of the most common applications for repair and rehabilitation of large-scale columns. Common types of fibers used for wrapping are carbon FRP (CFRP), glass FRP (GFRP), and aramid FRP (AFRP). Recently, steel FRP (SFRP) has been introduced as a new class of composites for strengthening applications. Up to now, there has been no experimental data available on the behavior of large-scale columns wrapped with SFRP sheets. Thus, in this paper, the behavior of nonreinforced and reinforced large-scale columns (300 × 1;200 mm) wrapped with CFRP and SFRP sheets is examined and compared with that of unwrapped columns. The experimental results include stress-strain behavior, ultimate stress, ultimate strain, dilation, and ductility of large-scale columns. This study presents the first ever insight into the strain variation of large-scale circular columns wrapped with CFRP and SFRP sheets using the digital image correlation technique (DICT). This technique is a photogrammetric technique that allows capturing strains from the surface of FRP-confined concrete. Results from DICT were used to analyze the strain efficiency of the SFRP sheets. Results indicate that the overall performance of the SFRP-wrapped concrete columns is superior to that of the CFRP-wrapped concrete columns. [ABSTRACT FROM AUTHOR]

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]

This paper aims to study the behavior of short reinforced concrete columns confined with external glass Fiber Reinforced Polymers (GFRP) sheets under eccentric loads. The experimental part of the study was achieved by testing 9 specimens under eccentric compression. Three eccentricity ratios corresponding to e/t = 0, 0.10, 0.50 in one direction of the column were used. Specimens were divided into three groups. The first group was the control one without confinement. The second group was fully wrapped with GFRP laminates before loading. The third group was wrapped under loading after reaching 75% of failure loads of the control specimens. The third group was investigated in order to represent the practical case of strengthening a loaded column with FRP laminates. All specimens were loaded until failure. The results show that GFRP laminates enhances both failure load and ductility response of eccentrically loaded column. Moreover, the study also illustrates the effect of confinement on the first crack load, lateral deformation, strain in reinforcement and failure pattern. Based on the analysis of the experimental results, a simple model has been proposed to predict the improvement of load carrying capacity under different eccentricity ratios. The predicted equation takes into consideration the eccentricity to cross section depth ratio, the ultimate strength of GFRE the thickness of wrapping laminate, and the time of wrapping (before loading and under loading). A good correlation was obtained between experimental and analytical results. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess subjective and objective outcomes in treating recurrent cubital tunnel at secondary neurolysis by nerve wrapping with a tissue engineered three-dimensional biomatrix. Five patients with a mean age of 44.1 years and an average follow-up of 13.3 months were included in the study. All patients had improvement in visual analogue scales. Four patients that had preoperative intrinsic atrophy with clawing had no clawing or intrinsic atrophy at final follow-up. Postoperatively, four of the five patients had two-point discrimination of 5 mm. Grip strength on average increased 90%. Three patients had an excellent outcome, one patient had a good outcome, and one patient had a fair outcome. All five patients said they would have surgery again. [ABSTRACT FROM PUBLISHER]

We describe a patient who developed acute chest pain and ST-segment elevation in the inferior leads on electrocardiography. In his control electrocardiography after 15 min, ST-segment elevation was observed in the anterior leads. Cardiac catheterization showed that there was wraparound left anterior descending artery and an occlusion in the proximal region. The occlusion was resolved by typical ballooning. To our knowledge, simultaneous ST elevations in anterior and inferior leads have been reported in the literature; however, in our case, with serial electrocardiographic (ECG) records, we realized that inferior ST-segment elevation altered to anterior ST-segment elevation. This indicates the importance of serial ECG records in emergency departments to explain the mechanism. [ABSTRACT FROM AUTHOR]

In this paper, two modelling systems used for the simulation of water resources management are compared. These modelling systems can be used in the implementation of the European Water Framework Directive or to perform any other kind of integrated assessment with regard to water resources management. In such investigations the use of models is inevitable, as integrated water resources management demands the survey of large areas as well as the inclusion of the different functions of the water cycle and water utilisation processes. Water quantity data provides important input for hydro-chemical, hydro-ecological or hydro-economic models. If no significant water resources management activities are realised in the basin under study, these data can be provided by simple rainfall-runoff models. If significant water resources management activities are realised or planned, the effects of these water resources management activities must be taken into consideration. Then, however, the use of water resources management models becomes necessary. Two such modelling systems, WRAP and WBalMo, are compared. Both have been designed for the development and revision of water resources management plans. Due to different approaches regarding the modelling routines the models lead to different results in the calculation of water quantities. By tracking the simulation algorithms, an understanding of the detected differences becomes possible. By adapting the spatial configuration of the modelled system, equivalent results can be obtained. [ABSTRACT FROM AUTHOR]

The overarching question addressed here is how syntactic structures based on constituency (dominance, c-command) are to be mapped onto linear phonetic strings. I argue that both prosodic principles and narrow-syntactic principles play a role in the linearization of syntactic structures. I take Kayne's (1994) Linear Correspondence Axiom as a starting point: (asymmetric) c-command maps onto precedence relations. Two wide-ranging predictions of Kayne's theory are that specifiers precede their heads and that a head can only have one specifier or adjunct. Although abundant evidence supports these predictions, there is nonetheless a well-known class of apparent counterexamples: Romance languages allow both rightward and multiple dislocations. I take the LCA to be a soft constraint, overruled by a constraint of the WRAP family that seeks to combine a verb and its extended projection in one intonational phrase. Apparent rightward movement is the outcome of rightward linearization forced by WRAP. The possibility of multiple dislocations is compatible with the LCA within the assumptions made here. [ABSTRACT FROM AUTHOR]

This article examines four leading multi-stakeholder labour monitoring organizations. All operating in the maquiladora industry, these organizations are viewed in light of the growing global trend toward industry self-regulation, or what has been referred to as the ‘global out-sourcing of regulation’. Their Board compositions, codes of conduct and monitoring and enforcement strategies are all examined as a means of tentatively positioning these organizations along an ‘egoist-instrumentalist-moralist’ ethical culture continuum. Such a framing provides insights into the perceived salience of these organizations’ broader stakeholders, the effectiveness of codes of conduct on workplace practices more generally, and the role that ethics plays in the governance and accountability of these increasingly important types of organizations. [ABSTRACT FROM AUTHOR]

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]

The ideal treatment for a boxer’s fracture remains controversial, particularly the degree of volar dislocation considered acceptable for nonoperative treatment. From December 2003 to December 2004, 25 patients who sustained a subcapital metacarpal fracture of the little finger with volar angulation between 30 to 75° were prospectively enrolled in the study. All patients were treated with a circular self-adherent wrap covering metacarpal bones II–V and buddy taping of the ring and little fingers for a period of 3 weeks while allowing immediate free range of motion. Final evaluation at a mean of 5 months revealed all patients to be satisfied without subjective functional impairment. All fractures healed, and the angulation of the fracture remained unchanged, but moderate shortening was observed. Active flexion of the metacarpophalangeal (MCP) joint was significantly lower on the fracture side, but as the median degree of MCP flexion was the same, this statistical difference was without clinical relevance. There was no loss in grip strength. A subjective long-term evaluation was performed by phone; at a median of 3 years, a QuickDash score gave a median of 0 point. Treating a boxer’s fracture with angulation of up to 75° by soft wrap and buddy taping resulted in satisfied patients and good clinical results. [ABSTRACT FROM AUTHOR]

Wrapped carbon nanotubes with polypropylene were synthesised by in situ graft method and used as a reinforcement agent for commercial polypropylene. Scanning electron microscopy and transmission electron microscopy revealed that carbon nanotubes were wrapped by polypropylene and dispersed homogeneously in polypropylene matrix. Infrared spectroscopy results showed that there was covalently linkage between polypropylene and carbon nanotubes via maleic anhydride grafting. The linkage was further confirmed by Raman observation. Furthermore, the X-ray diffraction research revealed that the carbon nanotubes act as nucleating agent to promote crystallisation. Owing to the uniform dispersion of carbon nanotubes and covalent adhesion between polypropylene and carbon nanotubes, the thermal stability of polypropylene was improved. [ABSTRACT FROM AUTHOR]

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]

Experimental studies are reported on upgrading the load carrying capacity of reinforced concrete rectangular columns by jacketing with glass fiber reinforced plasic flexible wraps. This article presents results of a comprehensive experimental investigation on the behavior of axially loaded rectangular columns that have been strengthened with glass fiber reinforced polymer (GFRP) wrap. This study is intended to examine several aspects related to the use of GFRP 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 the number of GFRP layers on the ultimate strength 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 (H/B, where H and B are, respectively, the longer and shorter sides of the cross section) are studied: H/B= 1.0, H/B= 1.25, and H/B= 1.66. Specimens with zero, one, and two layers of GFRP wrap are investigated. In total, nine specimens are subjected to axial compression which includes three control specimens. All the test specimens are loaded to failure in axial compression and the behavior of the specimens in the axial and transverse directions is investigated. The confinement provided by GFRP improves both the load carrying capacity and the ductility of the rectangular and square columns. This method of structural rehabilitation is shown to be applicable to rectangular sections. [ABSTRACT FROM AUTHOR]

This article presents a classification system for Water Resistive Barrier (WRB) products currently available on the North American market. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the clinical outcome for patients treated with walking cast immobilization and wrap early mobilization after surgical repair of acute Achilles tendon ruptures. A total of 39 consecutive patients with complete ruptures of the Achilles tendon were identified, treated, and functionally rehabilitated with either a walking cast or a wrap. Because the randomization was quasi-random, chi-square and t-tests were performed to compare the baseline characteristics. A statistically significant difference was present only for the injured side (p<0.05). Therefore, groups were considered comparable for analysis of outcome. All patients were evaluated at an average follow-up of 6.7 years (range 5–8 years). Functional postoperative treatment with a wrap allowed a significantly shorter hospital stay (p<0.05) as well as a shorter period to return to pre-injury sports level (p<0.01) compared with treatment with a walking cast. According to the modified Rupp score, 91.3% of patients in the walking cast group had a good or excellent result, as did 93.8% in the wrap group (p=0.9). Slight atrophy of the calf muscles was reported in 3 patients in the walking cast group (13.0%) and in 4 in the wrap group (25.0%). One re-rupture was reported in the walking cast group (4.3%). Functional treatment after surgical Achilles tendon repair is safe, and there is no increased risk of re-rupture or wound healing problems. Functional treatment with a wrap is preferable to treatment with a walking cast with respect to hospitalization time and return to sports. [ABSTRACT FROM AUTHOR]

In the late 1980s, with the advent of increased consumer environmental awareness, DuPont faced a challenge with its TYVEK® family of nonwoven polyethylene textile products. TYVEK is used in a wide variety of applications ranging from house wrap to medical packaging. One of the most visible portions of the business is envelopes used by FedEx (previously known as Federal Express), the well-known courier and delivery service and by the U.S. Postal Service. As early as 1988, end users began asking questions about the environmental characteristics of TYVEK envelopes. As these questions increased, DuPont began to address the concerns directly. In response to the market's concern and because of the increased availability of postconsumer-recycled (PCR) polyethylene, DuPont decided to put PCR polyethylene into TYVEK, beginning with the envelope business. Further, DuPont developed a recycling infrastructure for TYVEK because, although TYVEK consists entirely of high-density polyethylene, which is highly recyclable, no infrastructure was in place to recycle the material. These decisions produced a wide variety of technical and organizational challenges the firm had to overcome. This case study examines how DuPont made these choices and overcame the difficulties created by implementing needed changes. Whereas the envelope market for TYVEK embraced PCR polyethylene, other product markets resisted the innovation. The article closes with a discussion of the lessons learned from DuPont's experience. [ABSTRACT FROM AUTHOR]

We describe the WDM request/allocation protocol (WRAP), a media-access control protocol for wavelength-routed passive optical networks (WR-PONs) in which each node has a single fixed optical receiver and a single tunable optical transmitter. The protocol does not require a carrier sensing capability, a separate control channel, or any centralized control or scheduling. Access to transmission channels is regulated by allocations made at destination nodes in response to requests made by source nodes. Computer simulation is used to investigate three different allocation algorithms, one of which-the preferential/random algorithm-is shown to provide significantly better performance than the alternatives. Simulations are presented comparing the performance of WRAP to two previously proposed applicable protocols-the interleaved time division multiple access (I-TDMA) protocol, and the FatMAC protocol. WRAP is shown to provide fair and flexible access to the transmission capacity, enabling high network utilization to be achieved under a wide range of traffic conditions, while providing a guaranteed minimum bandwidth between each source-destination pair. We conclude that of the three protocols considered here, WRAP is the best-suited to general-purpose data communications applications such as local, campus, and metropolitan area networks [ABSTRACT FROM PUBLISHER]

The aim of the present study was to describe and assess a new method of fixation using a self-adhesive prosthesis (Adhesix™) in laparoscopic ventral rectopexy (LVR). The technical principles are based on a very low dissection and the adhesive properties of the prosthesis which can be applied to the rectum without stitches or staples. The prosthesis is made from polypropylene coated with a synthetic hydrogel. The binding of the prosthesis to rectum and vagina takes place in a wet environment after a few minutes and enables the shaping of the mesh on the surface of the rectum (wrap effect). Between March 2010 and March 2013, 41 patients were operated on using LVR with a self-adhesive prosthesis. The effectiveness of prosthesis fixation was evaluated in a subset of 27 patients suffering from complete rectal prolapse. With a median follow-up of 30 months, there were no major complications and no recurrence. In this initial experience, LVR with a self-adhesive prosthesis does not increase the risk of recurrence. No undesirable effects were associated with the prosthesis. [ABSTRACT FROM AUTHOR]

Vein grafts have been used to cope with several problems in peripheral nerve surgery, including vein wrapping of scarred nerves involved in chronic pain syndromes, vein caps for recurrent end-stump neuromas, vein conduits for nerve gaps after resection of neuromas-in-continuity, and following trauma. From 1993–1997, 30 vein grafts were performed in 28 patients. Five chronic peripheral nerve pain syndromes were treated by vein wrapping for two ulnar, two median and one radial sensory nerve, with significant pain resolution in all cases. Two recurrent digital neuromas were treated with vein caps, with pain resolution in each case. Nine patients with neuromas-in-continuity underwent neuroma resection and nerve repair with vein conduits. Twelve patients (14 nerves) underwent primary or delayed repair with vein conduits for nerve gaps following trauma. Sensory return measured by two point discrimination after repair of nerve gaps, following either neuroma-in-continuity resections or trauma, was 5–10 mm in 17 digital or common digital nerve injuries, and greater than 10 mm in three radial sensory nerve injuries. [ABSTRACT FROM AUTHOR]

The practice of 'vancomycin wrapping' of harvested hamstring autografts during Anterior Cruciate Ligament Reconstruction (ACLR) surgery has gathered recent interest. This practice involves the wrapping of harvested grafts in a vancomycin-soaked swab during the preparatory phase. Different techniques are observed, and a small number of studies have shown that pre-soaking hamstring ACLR grafts in this manner dramatically reduces the post-surgical infection rate compared with standard intravenous antibiotic prophylaxis alone. However, the literature surrounding this practice is surprisingly limited and thus the basis and rationale of the 'vancomycin wrap' has established itself largely without question. The exact popularity of this practice is difficult to establish but there has been increasing disclosure of its efficacy in reducing post-operative infection in ACLR since 2012. We provide a synopsis of the current literature surrounding vancomycin and its use in 'wraps' in ACLR to help apprise the surgeon of the nature of infection in ACLR, the rationale for vancomycin, whilst considering evidence to support alternatives and discussing potential ramifications for future practice., (Crown Copyright © 2019. Published by Elsevier B.V. All rights reserved.)

The founders of neurology in the late 19th century and early 20th century laid the foundation for modern geriatric neurology by detailed observations, in their patients, of the clinical expressions of aging of the nervous system. Further advances in clinical manifestations of aging and more detailed examination of disease states in the elderly accelerated in the last quarter of the 20th century. Basic, translational, and clinical research support of geriatric neurology studies expanded and advanced during this period and into the 21st century. The size and sophistication of this movement was stimulated by a number of factors: the successful development of geriatrics as a specialty in primary care, internal medicine, and psychiatry; the projected growth of the geriatric population; and the projections of the number of people with Alzheimer's disease. However, there were and continue to be inadequate numbers of trained geriatric neurologists available to care for the "silver tsunami" of elderly patients with age-related diseases that will present in the next 3 decades. The combination of massive investment in dementia/Alzheimer's research in the past decade, widespread awareness among researchers and trainees of the opportunities to do research in age-related diseases, and the need for further knowledge of neurodegenerative diseases led to a broad expansion of research efforts. Longitudinal clinical studies of the elderly and the advent of sophisticated neuroimaging, genetics, and laboratory techniques are advancing the field. The initiation of therapeutic interventions has led to cautious optimism about the ability to ameliorate suffering in these patients and diminish the burdens of central nervous system aging., (Copyright © 2019 Elsevier B.V. All rights reserved.)