1,704 research outputs found

    Numerical Modelling and Calibration of CFS Framed Shear Walls under Dynamic Loading

    Get PDF
    This paper describes the numerical modeling using OpenSees of steel sheathed cold-formed steel framed shear wall test specimens under dynamic loading. Two modeling phases were carried out; the first phase comprised non-linear models calibrated using existing reversed cyclic shear wall test data, and the second phase involved more advanced models calibrated using data from dynamic shake table tests of single- and double-storey shear walls as well as other ancillary test programs. The second phase models incorporated the behaviour of the hold-downs, floor framing and blocked bare frame, in addition to the sheathing. The final calibrated models were able to accurately predict the displacement and force response time histories of the single- and double-storey shear wall specimens. These calibrated models will later be relied on for Incremental Dynamic Analyses (IDA) of representative building structures to evaluate seismic design provisions for cold-formed steel framed shear walls to be used in conjunction with the National Building Code of Canada (NBCC)

    Effect of dissolved oxygen on the degradation activity and consumption capacity of white-rot fungi

    Get PDF
    Altres ajuts: acords transformatius de la UABIn recent decades, bioremediation using white rot fungi (WRF) has become an attractive alternative for the removal of xenobiotics from water. However, WRF are aerobic microorganisms whose degradative capacity may be reduced when operating in oxygen-restricted environments. This work determines the limiting dissolved oxygen level of Trametes versicolor in terms of degradation of two target micropollutants: bentazon and tributyl phosphate. When the dissolved oxygen concentration was set below 15 % saturation (1.3 mg O·L), the results revealed a considerable decrease in degradation capacity and laccase synthesis. Hence, 15 % dissolved oxygen was established as a reference value of aerobic conditions to assess dissolved oxygen profiles in both a rotating drum bioreactor (RDB) and a fixed-bed bioreactor (FBB). Restrictive oxygen conditions were achieved after an operating period of 24 h in the RDB and an empty bed contact time of 44 min in the FBB. In addition, growth kinetics on Q. ilex wood and organic matter removal (in terms of COD) were studied, obtaining 0.059 mg ergosterol·g wood DW·day and 16.23 mg O·L·h, respectively. Therefore, T. versicolor has demonstrated a remarkable ability to assimilate complex carbon sources and a high micropollutant degradation activity, especially when operating in non-limiting oxygen regimes

    Implementation and evaluation of employee health and wellness program using RE-AIM framework

    Get PDF
    Purpose: To describe the design, implementation, and evaluation of an employer-sponsored health screening program [Employee Health and Wellness Program (EHWP)] in an academic healthcare system in Pakistan.Design/methodology/approach: One-year after implementation, we use the RE-AIM framework (Reach, Effectiveness, Adoption, Implementation and Maintenance) to evaluate and report participant- and organizational-level indicators of success.Findings: Of 5286 invited employees, 4523 (86%) completed blood work and 1809 (34%) completed health risk assessment (Reach). Of the 915 (51%) who required referrals, 3% were referred for new diagnoses of diabetes, hepatitis C or severe anemia; 63% for elevated 10- year risk of cardiometabolic diseases (cardiovascular disease and diabetes); and 25% for counseling for depression, obesity or smoking cessation (Effectiveness). Employees’ barriers to enrollment were explored (Adoption). While institutional costs were considered nominal (US $ 20/employee), organizational barriers were identified (Implementation). Finally, 97% of users reported interest in enrollment if EHWP was offered again (Maintenance).Originality/ value: In a country with minimal focus on adult preventive care, we report the impact of an employer-offered wellness program that identified new risk factors and offered referral for ongoing care. Employees reported a positive experience and were willing to reenroll. Using the RE-AIM framework, we have defined indicators in the real-world setting, that can be used effectively by other institutions to start such a program

    Mindfulness and Creative Process Engagement: The Mediating Role of Workplace Relational Systems

    Get PDF
    Purpose Despite widespread recognition of the importance of mindfulness in organizational science literature, little is known about how mindfulness motivates individuals to configure information processing and team member exchange relationships to increase creative process engagement. Drawing on motivated information processing theory, this study conceptualizes and empirically examines whether and how mindfulness motivates individuals toward creative process engagement. Design/methodology/approach The authors collected data through an online survey from 311 respondents working in the Research and Development (R&D) departments of organizations in multiple industries in Pakistan. For analytical purposes, the authors have applied the structural equation modeling technique. Findings This study advances a different view of individual mindfulness on the creative process engagement in the following ways. First, mindfulness enables individuals to self-regulate in specific situations and become effective in fostering creative process engagement. Second, this study extends research on relational information processing by linking it to mindfulness and creative process engagement. Relational information processing partially mediates the relationship between mindfulness and creative process engagement. Third, this study highlights that mindfulness motivates individuals to focus more on developing quality working relationships, but they seem less willing to participate in idea generation and problem-solving solutions. Originality/value The study findings provide implications for research on mindfulness, creativity and motivated information processing to enhance individuals’ creative process engagements. The authors also discuss the implications for executives on the relational and creative benefits of mindfulness

    Numerical modeling of mechanical behavior of clinch connections at breaking out and shearing

    Get PDF
    © The Authors, published by EDP Sciences, 2017. This article describes an approach to constructing the defining relationships between increment of true stresses and true deformations, with considering the contact interaction of elastoplastic deformed bodies among each other. Within the framework of finite element method, solving these problems in case of "breaking out" and "shearing" in the clinch joint, the stress fields in the zone of the clinch connection are defined, and recommendations are given for realizing the process of their creation

    Functionalized Thermoplastic Polyurethane Nanofibers: An Innovative Triboelectric Energy Generator

    Get PDF
    A triboelectric nanogenerator (TENG) is one of the most significantly innovative microdevices for built-in energy harvesting with wearable and portable electronics. In this study, the forcespinning technology was used to synthesize a nanofiber (NF) mat-based TENG. Polyvinylidene fluoride (PVDF) membrane was used as the negative triboelectric electrode/pole, and chemically designed and functionalized thermoplastic polyurethane (TPU) was used as the positive electrode/pole for the TENG. The electronic interference, sensitivity, and gate voltage of the synthesized microdevices were investigated using chemically modified bridging of multi-walled carbon nanotubes (MWCNT) with a TPU polymer repeating unit and bare TPU-based positive electrodes. The chemical functionality of TPU NF was integrated during the NF preparation step. The morphological features and the chemical structure of the nanofibers were characterized using a field emission scanning electron microscope and Fourier-transform infrared spectroscopy. The electrical output of the fabricated MWCNT-TPU/PVDF TENG yielded a maximum of 212 V in open circuit and 70 µA in short circuit at 240 beats per minute, which proved to be 79% and 15% higher than the TPU/PDVF triboelectric nanogenerator with an electronic contact area of 3.8 × 3.8 cm2, which indicates that MWCNT enhanced the electron transportation facility, which results in significantly enhanced performance of the TENG. This device was further tested for its charging capacity and sensory performance by taking data from different body parts, e.g., the chest, arms, feet, hands, etc. These results show an impending prospect and versatility of the chemically functionalized materials for next-generation applications in sensing and everyday energy harvesting technology

    Emerging bacterial resistance patterns in febrile neutropenic patients: experience at a tertiary care hospital in Pakistan

    Get PDF
    Objective: To look at the clinical presentations, spectrum and site of isolation of the organisms, sensitivity patterns of the organisms and the antibiotic prescribing practices for the treatment of febrile neutropenic patients at our hospital.Methods: The data were collected retrospectively from the records of all neutropenic patients with an absolute neutrophil count (ANC) of less than 500/ml admitted during the period of 3 years from August 1999 to July 2002 at AKUH.Results: Out of the total of 404 patients, 65% had hematological malignancies and around half of them had leukaemia, 86% of the patients presented with fever. A total of 124 bacterial organisms were isolated from 96 patients among which 47% were gram positive and 53% were gram negative organisms; 16.1% of the patients had septicaemia. Coagulase Negative Staphylococci (CoNS) were the most common gram positive and E. coli was the most commonly isolated gram negative organism. Most of the gram positive organisms were isolated from blood (67%). There was emerging resistance to all commonly used antibiotics including imipenem, cloxacillin, vancomycin and amikacin. The average duration of neutropenia was 6.4 days. The mortality rate was 6%.CONCLUSION: There is increasing trend of gram negative organisms developing resistance to commonly used antibiotics. Gram positive bacteria including Enterococcus spp. and CoNS are also showing emerging resistance to vancomycin

    Mitochondrial Ca(2+) uptake by the voltage-dependent anion channel 2 regulates cardiac rhythmicity.

    Get PDF
    Tightly regulated Ca(2+) homeostasis is a prerequisite for proper cardiac function. To dissect the regulatory network of cardiac Ca(2+) handling, we performed a chemical suppressor screen on zebrafish tremblor embryos, which suffer from Ca(2+) extrusion defects. Efsevin was identified based on its potent activity to restore coordinated contractions in tremblor. We show that efsevin binds to VDAC2, potentiates mitochondrial Ca(2+) uptake and accelerates the transfer of Ca(2+) from intracellular stores into mitochondria. In cardiomyocytes, efsevin restricts the temporal and spatial boundaries of Ca(2+) sparks and thereby inhibits Ca(2+) overload-induced erratic Ca(2+) waves and irregular contractions. We further show that overexpression of VDAC2 recapitulates the suppressive effect of efsevin on tremblor embryos whereas VDAC2 deficiency attenuates efsevin\u27s rescue effect and that VDAC2 functions synergistically with MCU to suppress cardiac fibrillation in tremblor. Together, these findings demonstrate a critical modulatory role for VDAC2-dependent mitochondrial Ca(2+) uptake in the regulation of cardiac rhythmicity

    Static and Dynamic DNA Loops form AP-1-Bound Activation Hubs during Macrophage Development

    Get PDF
    The three-dimensional arrangement of the human genome comprises a complex network of structural and regulatory chromatin loops important for coordinating changes in transcription during human development. To better understand the mechanisms underlying context-specific 3D chromatin structure and transcription during cellular differentiation, we generated comprehensive in situ Hi-C maps of DNA loops during human monocyte-to-macrophage differentiation. We demonstrate that dynamic looping events are regulatory rather than structural in nature and uncover widespread coordination of dynamic enhancer activity at preformed and acquired DNA loops. Enhancer-bound loop formation and enhancer-activation of preformed loops represent two distinct modes of regulation that together form multi-loop activation hubs at key macrophage genes. Activation hubs connect 3.4 enhancers per promoter and exhibit a strong enrichment for Activator Protein 1 (AP-1) binding events, suggesting multi-loop activation hubs driven by cell-type specific transcription factors may represent an important class of regulatory chromatin structures for the spatiotemporal control of transcription
    corecore