258 research outputs found

    Characteristics, seasonality and sources of carbonaceous and ionic components in the tropical aerosols from Indian region

    Get PDF
    To better characterize the tropical aerosols in Indian region, PM<sub>10</sub> samples collected from Chennai, India (13.04° N; 80.17° E) were analyzed for carbonaceous and water-soluble ionic components. Concentration ranges of elemental carbon (EC) and organic carbon (OC) were 2.4–14 μg m<sup>−3</sup> (ave. 6.5 μg m<sup>−3</sup>) and 3.2–15.6 μg m<sup>−3</sup> (ave. 9.1 μg m<sup>−3</sup>) in winter samples whereas they were 1.1–2.5 μg m<sup>−3</sup> (ave. 1.6 μg m<sup>−3</sup>) and 4.1–17.6 μg m<sup>−3</sup> (ave. 9.7 μg m<sup>−3</sup>) in summer samples, respectively. Concentration of secondary organic carbon (SOC) retrieved from EC-tracer method was 4.6±2.8 μg m<sup>−3</sup> in winter and 4.3±2.8 μg m<sup>−3</sup> in summer. OC accounted for 38.5±14 % (<i>n</i> = 49) of combined concentrations of carbonaceous and ionic components in PM<sub>10</sub>. We also found that OC concentrations are generally higher than those of SO<sub>4</sub><sup>2−</sup> (8.8±2.5 μg m<sup>−3</sup> and 4.1±2.7 μg m<sup>−3</sup> in winter and summer, respectively), which was the most abundant ionic species (57 %) followed by NH<sub>4</sub><sup>+</sup> (15 %) >NO<sub>3</sub><sup>−</sup>>Cl<sup>−</sup>>K<sup>+</sup>>Na<sup>+</sup>> Ca<sup>2+</sup>>MSA<sup>−</sup>>Mg<sup>2+</sup>. The mass fractions of EC, organic matter (OM) and ionic species varied seasonally, following the air mass trajectories and corresponding source strength. Based on mass concentration ratios of selected components and relations of EC and OC to marker species, we found that biofuel/biomass burning is a major source of atmospheric aerosols in South and Southeast Asia. The high concentrations of SOC and WSOC/OC ratios (ave. 0.45; <i>n</i> = 49) as well as good correlations between SOC and WSOC suggest that the secondary production of organic aerosols during long-range atmospheric transport is also significant in this region. This study provides the baseline data of carbonaceous aerosols for southern part of the Indian subcontinent

    On variable frequency microwave processing of heterogeneous chip-on-board assemblies

    Get PDF
    Variable Frequency Microwave (VFM) processing of heterogeneous chip-on-board assemblies is assessed using a multiphysics modelling approach. The Frequency Agile Microwave Oven Bonding System (FAMOBS) is capable of rapidly processing individual packages on a Chip-On-Board (COB) assembly. This enables each package to be processed in an optimal manner, with temperature ramp rate, maximum temperature and process duration tailored to the specific package, a significant benefit in assemblies containing disparate package types. Such heterogeneous assemblies may contain components such as large power modules alongside smaller modules containing low thermal budget materials with highly disparate processing requirements. The analysis of two disparate packages has been assessed numerically to determine the applicability of the dual section microwave system to curing heterogeneous devices and to determine the influence of differing processing requirements of optimal process parameters

    M40 GRADE SELF COMPACTED CONCRETE & COMPARISION IN BEHAVIOUR WITH M40 CONVENTIONAL CONCRETE

    Get PDF
    Self-compacting concrete (SCC) can get rid of the problem, because it is built to consolidate under its very own mass. Normal concrete was created by utilizing IS method and self-compacting concrete was created with a simple mix design suggested by Nan Su. SCC was created in 1988’s by Prof. Hagime Okamura in Japan. Conventional concrete has a tendency to present an issue with regard to sufficient consolidation in thin sections or regions of congested reinforcement, which results in a sizable amount of entrapped air voids and compromises the durability and strength from the concrete. SCC was among the special concrete in around the globe. This project handles the comparison of two various kinds of high strength concretes they're high strength conventional concrete and strength self-compacting concrete. An experimental and statistical study mechanical qualities, for example compressive strength, flexural strength and split tensile strength of self-compacting concrete (SCC) and also the corresponding qualities of conventional concrete (CC) were studied

    In Vivo Characterization of a Wireless Telemetry Module for a Capsule Endoscopy System Utilizing a Conformal Antenna

    Get PDF
    This paper describes the design, fabrication, packaging, and performance characterization of a conformal helix antenna created on the outside of a 10 mm ×30 mm capsule endoscope designed to operate at a carrier frequency of 433 MHz within human tissue. Wireless data transfer was established between the integrated capsule system and an external receiver. The telemetry system was tested within a tissue phantom and in vivo porcine models. Two different types of transmission modes were tested. The first mode, replicating normal operating conditions, used data packets at a steady power level of 0 dBm, while the capsule was being withdrawn at a steady rate from the small intestine. The second mode, replicating the worst-case clinical scenario of capsule retention within the small bowel, sent data with stepwise increasing power levels of –10, 0, 6, and 10 dBm, with the capsule fixed in position. The temperature of the tissue surrounding the external antenna was monitored at all times using thermistors embedded within the capsule shell to observe potential safety issues. The recorded data showed, for both modes of operation, a low error transmission of 10−3 packet error rate and 10−5 bit error rate and no temperature increase of the tissue according to IEEE standards

    Challenges to Implementation of the Co-Curriculum in Accredited Pharmacy Programs

    Get PDF
    Objective. To determine areas of concern, and challenges to implementing and assessing the co-curriculum in accredited Doctor of Pharmacy programs, along with how confident programs are in their ability to meet the co-curriculum requirement as mandated by the Accreditation Council for Pharmacy Education (ACPE). Methods. A survey was administered to all ACPE-accredited pharmacy programs to collect information regarding areas of concern, challenges, and confidence in their ability to meet the co-curriculum requirement. The frequency of responses to items are presented along with comparisons based on characteristics, including institution type, cohort size, most recent ACPE accreditation review, and supporting offices. Results. The most common concerns centered on the documentation and assessment process. The most commonly reported challenges were lack of enthusiasm or buy-in from faculty, staff, and students; lack of a clear definition of co-curriculum; and faculty time and insufficient staff. Overall, programs had a high level of confidence in their ability to meet the requirements for co-curriculum. The only differences found were related to supporting offices and cohort size. Conclusion. The results suggest that having supporting offices may reduce the co-curriculum burden. Similarly, student cohort size may have an impact on the challenges for some programs, particularly those with moderate-sized cohorts reporting challenges related to faculty and staff. Further research is needed to determine how programs address these critical issues, and to explore whether programs report differently on these areas after completing an accreditation review. The study results may be useful to members of the Academy when evaluating co-curriculum

    Co-Curriculum Implementation and Assessment in Accredited Doctor of Pharmacy Programs

    Get PDF
    Objective. To determine how accredited Doctor of Pharmacy programs implement and evaluate the co-curriculum requirement as mandated by the Accreditation Council for Pharmacy Education (ACPE). Methods. A survey was administered to all ACPE-accredited pharmacy programs to collect information regarding how co-curriculum models were being implemented, including types of activities, structure, learning outcomes, oversight, and assessment. The frequency of responses to items were presented to describe the general features of co-curriculum models. Results. The types of co-curricular activities reported by programs were generally consistent, with the majority of programs categorizing these activities and allowing students to choose which they would engage in. Most respondents reported that the program mapped co-curricular activities to learning outcomes, primarily ACPE Standards 1-4. The structural oversight of the co-curriculum typically included a co-curriculum committee, subcommittee, or task force, and supporting offices. The most common offices/departments involved in the co-curriculum were assessment, student affairs/services, experiential education, and academic/curricular affairs. The most common assessments were reflections, self-assessment surveys, and checklists. Conclusion. In most programs, implementation of the co-curriculum was a joint effort among various individuals, committees, and offices. Given the developing nature of programs, descriptive studies should be repeated to identify how programs develop and enhance co-curriculum models. The study results may be useful to members of the Academy when evaluating the current state of co-curriculum implementation and potential areas for program development

    Co-Curriculum Implementation and Assessment in Accredited Doctor of Pharmacy Programs

    Get PDF
    Objective. To determine how accredited Doctor of Pharmacy programs implement and evaluate the co-curriculum requirement as mandated by the Accreditation Council for Pharmacy Education (ACPE). Methods. A survey was administered to all ACPE-accredited pharmacy programs to collect information regarding how co-curriculum models were being implemented, including types of activities, structure, learning outcomes, oversight, and assessment. The frequency of responses to items were presented to describe the general features of co-curriculum models. Results. The types of co-curricular activities reported by programs were generally consistent, with the majority of programs categorizing these activities and allowing students to choose which they would engage in. Most respondents reported that the program mapped co-curricular activities to learning outcomes, primarily ACPE Standards 1-4. The structural oversight of the co-curriculum typically included a co-curriculum committee, subcommittee, or task force, and supporting offices. The most common offices/departments involved in the co-curriculum were assessment, student affairs/services, experiential education, and academic/curricular affairs. The most common assessments were reflections, self-assessment surveys, and checklists. Conclusion. In most programs, implementation of the co-curriculum was a joint effort among various individuals, committees, and offices. Given the developing nature of programs, descriptive studies should be repeated to identify how programs develop and enhance co-curriculum models. The study results may be useful to members of the Academy when evaluating the current state of co-curriculum implementation and potential areas for program development

    Maintaining Force Control Despite Changes in Emotional Context Engages Dorsomedial Prefrontal and Premotor Cortex

    Get PDF
    Viewing emotional as compared with neutral images results in an increase in force production. An emotion-driven increase in force production has been associated with increased brain activity in ventrolateral prefrontal cortex and primary motor cortex (M1). In many instances, however, force production must be held constant despite changes in emotional state and the neural circuits underlying this form of control are not well understood. To address this issue, we designed a task in which subjects viewed pleasant, unpleasant, and neutral images during a force production task. We measured brain activity using functional magnetic resonance imaging and examined functional connectivity between emotion and motor circuits. Despite similar force performance across conditions, increased brain activity was evidenced in dorsomedial prefrontal cortex (dmPFC) and left ventral premotor cortex (PMv) when force was produced during emotional as compared with neutral conditions. Connectivity analyses extended these findings by demonstrating a task-dependent functional circuit between dmPFC and ventral and dorsal portions of premotor cortex. Our findings show that when force production has to be consistent despite changes in emotional context, a functional circuit between dmPFC and PMv and dorsal premotor cortex is engaged
    corecore