55 research outputs found

    MODELING RATE DEPENDENT DURABILITY OF LOW-Ag SAC INTERCONNECTS FOR AREA ARRAY PACKAGES UNDER TORSION LOADS

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    The thesis discusses modeling rate-dependent durability of solder interconnects under mechanical torsion loading for surface mount area array components. The study discusses an approach to incorporate strain-rate dependency in durability estimation for solder interconnects. The components under study are two configurations of BGAs (ball grid array) assembled with select lead-free solders. A torsion test setup is used to apply displacement controlled loads on the test board. Accelerated test load profile is experimentally determined. Torsion test is carried out for all the components under investigation to failure. Strain-rate dependent (Johnson-Cook model) and strain-rate independent, elastic-plastic properties are used to model the solders in finite element simulation. Damage model from literature is used to estimate the durability for SAC305 solder to validate the approach. Test data is used to extract damage model constants for SAC105 solder and extract mechanical fatigue durability curve

    DEVELOPMENT OF TEST ENVIRONMENTS FOR REVERSE ASSIST FUNCTIONS AS APPLIED TO AN A-DOUBLE VEHICLE COMBINATION

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    High-capacity transport vehicles reduce costs and improve efficiency. Long vehicle combinations such as an A-double combination vehicle (Tractor + semitrailer + dolly + semitrailer) improve transportation efficiency but they are extremely difficult to manoeuvre in tight spaces and in the reverse direction. This document summarizes developing environments to test reverse assist functions as applied to the A-double combination vehicle. These environments create a rapid prototyping platform consisting of a virtual and a scaled environment to test and validate controller concepts. The behaviour of the plant model in the virtual environment, the scaled vehicle model and the plant model in VTM (Volvo Truck Model) are studied and compared. A proportional controller is developed to test the environments and evaluate the process of concept development using the rapid prototype platform. The controller performance is evaluated and a possibility of incorporating integral controller is discussed

    Hardware-Software Co-Design for Network Performance Measurement

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    Diagnosing performance problems in networks is important, for example to determine where packets experience high latency or loss. However, existing performance diagnoses are constrained by limited switch mechanisms for measurement. Alternatively, operators use endpoint information indirectly to infer root causes for problematic latency or drops. Instead of designing piecemeal solutions to work around such switch restrictions, we believe that the right approach is to co-design language abstractions and switch hardware primitives for network performance measurement. This approach provides confidence that the switch primitives are sufficiently general, i.e., they can support a variety of existing and unanticipated use cases. We present a declarative query language that allows operators to ask a diverse set of network performance questions. We show that these queries can be implemented efficiently in switch hardware using a novel programmable key-value store primitive. Our preliminary evaluations show that our hardware design is feasible at modest chip area overhead relative to existing switching chips

    Clinical manifestation and prevalence of peripheral neuropathy and nerve dysfunction in patients with chronic kidney disease

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    Background: Chronic Kidney Disease (CKD) is recognized as a major health problem. Prevalence of CKD is rising continuously; mostly CKD is affecting the elderly aged population and/or patients with diabetes and hypertension. Present study was aimed to explore clinical manifestation and evaluate the prevalence of peripheral neuropathy and peripheral nerve dysfunction in CKD patients attending our hospital with reference to the severity and duration of the CKD.Methods: The present cross sectional study was conducted in 74 patients affected with chronic kidney disease, of different age groups at the medical wards of King George Hospital, Visakhapatnam. The presence of peripheral nerve dysfunction was assessed by nerve dysfunction clinically (motor or sensory symptoms and signs) and electrophysiological nerve conduction studies.Results: Out of 74 patients, 65% of study population was suffering from chronic kidney disease with peripheral nerve dysfunction. The peripheral nerves dysfunction was more prevalent in elder age (>65 years) subjects when compared to subjects with age <65 years. Moreover, the results shown that the rate of prevalence of peripheral nerves dysfunction was observed higher in subjects with longer duration of CKD. Male subjects were affected more when creatinine clearance is <15 ml/minute. Both sexes were affected equally when creatinine clearance is between 30-59 ml/minute.Conclusion: This study enlightens the prevalence and clinical presentation of peripheral nerve dysfunction in patients with CKD. The CKD was found to cause peripheral neuropathy including overt and subclinical neuropathy, of which distal symmetrical sensory motor neuropathy was common in CKD. The prevalence of peripheral neuropathy was directly proportional to duration and severity of CKD.

    Risk factors for orofacial clefts in India:A case-control study

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    BACKGROUND: Orofacial clefts (OFC) are linked with several genetic and environmental factors. The aim of this study was to explore the association of potential risk factors with OFCs in India. METHODS: This was a hospital-based, matched case-control (1:4 ratio; matching done for parity) study conducted in Hyderabad, Bengaluru, and Delhi-National Capital Region. Cases (nonsyndromic clefts) were recruited from treatment centers, while controls (live births) were recruited from maternity centers. Information on exposures was collected during personal interviews. Exposures of interest included folic acid supplementation during the peri-conceptional period, consanguineous marriage, exposure to drugs, infections during pregnancy, family history of OFC, and dietary factors. RESULTS: A total of 785 participants were included in the study: 157 cases and 628 controls. A family history of cleft lip/palate (adjusted odds ratio [AOR], 15.48; 95% confidence interval [CI], 4.36-54.96; p value = 0.001), exclusive vegetarianism (AOR, 4.47; 95% CI, 1.83-10.98; p value = 0.001), and delayed first conception (AOR, 2.55, 95% CI, 1.25-5.21, p = 0.01) were found to be strongly associated with higher risk of OFCs. Supplementation with folic acid during first 3 months of pregnancy was not found to be protective against OFCs (AOR, 1.24; 95% CI, 0.59-2.58; p value = 0.56). CONCLUSION: Our study confirmed the importance of family history as a risk factor for OFC. Our study did not show an association with folic acid supplementation but was underpowered to detect small effects. Our finding of higher risk among vegetarians requires replication. Birth Defects Research 109:1284-1291, 2017. © 2017 The Authors. Birth Defects Research Published by Wiley Periodicals, Inc

    Measuring the health-related Sustainable Development Goals in 188 countries : a baseline analysis from the Global Burden of Disease Study 2015

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    Background In September, 2015, the UN General Assembly established the Sustainable Development Goals (SDGs). The SDGs specify 17 universal goals, 169 targets, and 230 indicators leading up to 2030. We provide an analysis of 33 health-related SDG indicators based on the Global Burden of Diseases, Injuries, and Risk Factors Study 2015 (GBD 2015). Methods We applied statistical methods to systematically compiled data to estimate the performance of 33 health-related SDG indicators for 188 countries from 1990 to 2015. We rescaled each indicator on a scale from 0 (worst observed value between 1990 and 2015) to 100 (best observed). Indices representing all 33 health-related SDG indicators (health-related SDG index), health-related SDG indicators included in the Millennium Development Goals (MDG index), and health-related indicators not included in the MDGs (non-MDG index) were computed as the geometric mean of the rescaled indicators by SDG target. We used spline regressions to examine the relations between the Socio-demographic Index (SDI, a summary measure based on average income per person, educational attainment, and total fertility rate) and each of the health-related SDG indicators and indices. Findings In 2015, the median health-related SDG index was 59.3 (95% uncertainty interval 56.8-61.8) and varied widely by country, ranging from 85.5 (84.2-86.5) in Iceland to 20.4 (15.4-24.9) in Central African Republic. SDI was a good predictor of the health-related SDG index (r(2) = 0.88) and the MDG index (r(2) = 0.2), whereas the non-MDG index had a weaker relation with SDI (r(2) = 0.79). Between 2000 and 2015, the health-related SDG index improved by a median of 7.9 (IQR 5.0-10.4), and gains on the MDG index (a median change of 10.0 [6.7-13.1]) exceeded that of the non-MDG index (a median change of 5.5 [2.1-8.9]). Since 2000, pronounced progress occurred for indicators such as met need with modern contraception, under-5 mortality, and neonatal mortality, as well as the indicator for universal health coverage tracer interventions. Moderate improvements were found for indicators such as HIV and tuberculosis incidence, minimal changes for hepatitis B incidence took place, and childhood overweight considerably worsened. Interpretation GBD provides an independent, comparable avenue for monitoring progress towards the health-related SDGs. Our analysis not only highlights the importance of income, education, and fertility as drivers of health improvement but also emphasises that investments in these areas alone will not be sufficient. Although considerable progress on the health-related MDG indicators has been made, these gains will need to be sustained and, in many cases, accelerated to achieve the ambitious SDG targets. The minimal improvement in or worsening of health-related indicators beyond the MDGs highlight the need for additional resources to effectively address the expanded scope of the health-related SDGs.Peer reviewe

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

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    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    American Journal of Advances in Medical Science Dermatological manifestation of lightning injury

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    Abstract Lightning is one of the most common naturally occurring global phenomena. Among various types of lightning, cloud to ground discharges possesses the most destructive effects. Lightning injuries are more common in rural or exposed environments than in urban areas. In the present article, a case of Lightning injury causing cutaneous manifestation in the form of superficial burns resembling miniature fern tree (Lichtenberg Figures) is reported

    Assessment of the Status of National Oral Health Policy in India

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    Background National oral health policy was conscripted by the Indian Dental Association (IDA) in 1986 and was accepted as an integral part of National Health Policy (NHP) by the Central Council of Health and Family Welfare in one of its conferences in the year 1995. Objectives of this paper were to find out the efforts made or going on towards its execution, its current status and recent oral health-related affairs or programs, if any. Methods Literature search was done using the institutional library, web-based search engines like ‘Google’ and ‘PubMed’ and also by cross referencing. It yielded 108 articles, of which 50 were excluded as they were not pertinent to the topic. Twenty-four were of global perspective rather than Indian and hence were not taken into account and finally 34 articles were considered for analyses. Documents related to central and state governments of India were also considered. Results All the articles considered for analysis were published within the past 10 years with gradual increase in number which depicts the researchers’ increasing focus towards oral health policy. Criticisms, suggestions and recommendations regarding national oral health programs, dental manpower issues, geriatric dentistry, public health dentistry, dental insurance, oral health inequality, and public-private partnerships have taken major occupancies in the articles. Proposals like “model for infant and child oral health promotion” and “oral health policy phase 1 for Karnataka” were among the initiatives towards national oral health policy. Conclusion The need for implementation of the drafted oral health policy with modification that suits the rapidly changing oral health system of this country is inevitable
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