439 research outputs found

    Finite size scaling for quantum criticality using the finite-element method

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    Finite size scaling for the Schr\"{o}dinger equation is a systematic approach to calculate the quantum critical parameters for a given Hamiltonian. This approach has been shown to give very accurate results for critical parameters by using a systematic expansion with global basis-type functions. Recently, the finite element method was shown to be a powerful numerical method for ab initio electronic structure calculations with a variable real-space resolution. In this work, we demonstrate how to obtain quantum critical parameters by combining the finite element method (FEM) with finite size scaling (FSS) using different ab initio approximations and exact formulations. The critical parameters could be atomic nuclear charges, internuclear distances, electron density, disorder, lattice structure, and external fields for stability of atomic, molecular systems and quantum phase transitions of extended systems. To illustrate the effectiveness of this approach we provide detailed calculations of applying FEM to approximate solutions for the two-electron atom with varying nuclear charge; these include Hartree-Fock, density functional theory under the local density approximation, and an "exact"' formulation using FEM. We then use the FSS approach to determine its critical nuclear charge for stability; here, the size of the system is related to the number of elements used in the calculations. Results prove to be in good agreement with previous Slater-basis set calculations and demonstrate that it is possible to combine finite size scaling with the finite-element method by using ab initio calculations to obtain quantum critical parameters. The combined approach provides a promising first-principles approach to describe quantum phase transitions for materials and extended systems.Comment: 15 pages, 19 figures, revision based on suggestions by referee, accepted in Phys. Rev.

    The long-term effects of Kerala Diabetes Prevention Program on diabetes incidence and cardiometabolic risk:a study protocol

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    Introduction: India currently has more than 74.2 million people with Type 2 Diabetes Mellitus (T2DM). This is predicted to increase to 124.9 million by 2045. In combination with controlling blood glucose levels among those with T2DM, preventing the onset of diabetes among those at high risk of developing it is essential. Although many diabetes prevention interventions have been implemented in resource-limited settings in recent years, there is limited evidence about their long-term effectiveness, cost-effectiveness, and sustainability. Moreover, evidence on the impact of a diabetes prevention program on cardiovascular risk over time is limited. Objectives: The overall aim of this study is to evaluate the long-term cardiometabolic effects of the Kerala Diabetes Prevention Program (K-DPP). Specific aims are 1) to measure the long-term effectiveness of K-DPP on diabetes incidence and cardiometabolic risk after nine years from participant recruitment; 2) to assess retinal microvasculature, microalbuminuria, and ECG abnormalities and their association with cardiometabolic risk factors over nine years of the intervention; 3) to evaluate the long-term cost-effectiveness and return on investment of the K-DPP; and 4) to assess the sustainability of community engagement, peer-support, and other related community activities after nine years. Methods: The nine-year follow-up study aims to reach all 1007 study participants (500 intervention and 507 control) from 60 randomized polling areas recruited to the original trial. Data are being collected in two phases. In phase 1 (Survey), we are admintsering a structured questionnaire, undertake physical measurements, and collect blood and urine samples for biochemical analysis. In phase II, we are inviting participants to undergo retinal imaging, body composition measurements, and ECG. All data collection is being conducted by trained Nurses. The primary outcome is the incidence of T2DM. Secondary outcomes include behavioral, psychosocial, clinical, biochemical, and retinal vasculature measures. Data analysis strategies include a comparison of outcome indicators with baseline, and follow-up measurements conducted at 12 and 24 months. Analysis of the long-term cost-effectiveness of the intervention is planned. Discussion: Findings from this follow-up study will contribute to improved policy and practice regarding the long-term effects of lifestyle interventions for diabetes prevention in India and other resource-limited settings. Trial registration: Australia and New Zealand Clinical Trials Registry–(updated from the original trial)ACTRN12611000262909; India: CTRI/2021/10/037191.publishedVersionPeer reviewe

    Depression Symptoms and Antidepressant Medicine Use in Diabetes Prevention Program Participants

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    OBJECTIVE: To assess depression markers (symptoms and antidepressant medicine use) in Diabetes Prevention Program (DPP) participants and to determine whether changes in depression markers during the course of the study were associated with treatment arm, weight change, physical activity level, or participant demographic characteristics. RESEARCH DESIGN AND METHODS: DPP participants (n = 3,187) in three treatment arms (intensive lifestyle, metformin, and placebo) completed the Beck Depression Inventory (BDI) and reported on use of antidepressant medicines at randomization and subsequently at each annual visit (average duration in study 3.2 years). RESULTS: On study entry, 10.3% of participants had BDI scores > or =11, which was used as a threshold for mild depression, 5.7% took antidepressant medicines, and 0.9% had both depression markers. During the DPP, the proportion of participants with elevated BDI scores declined (from 10.3% at baseline to 8.4% at year 3), while the proportion taking antidepressant medicines increased (from 5.7% at baseline to 8.7% at year 3), leaving the proportion with either marker unchanged. These time trends were not significantly associated with the DPP treatment arm. Depression markers throughout the study were associated with some participant demographic factors, adjusted for other factors. Men were less likely to have elevated depression scores and less likely to use antidepressant medicine at baseline (9.0% of men and 17.9% of women had at least one marker of depression) and throughout the study (P or =11 (P = 0.03), but white participants were more likely to be taking antidepressant medicine than any other racial/ethnic group (P <0.0001). CONCLUSIONS: DPP participation was not associated with changes in levels of depression. Countervailing trends in the proportion of DPP participants with elevated depression symptoms and the proportion taking antidepressant medicine resulted in no significant change in the proportion with either marker. The finding that those taking antidepressant medicine often do not have elevated depression symptoms indicates the value of assessing both markers when estimating overall depression rates

    A Randomized Controlled Trial of Parental Asthma Coaching to Improve Outcomes Among Urban Minority Children

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    Investigate if asthma coaching reduces emergency department (ED) visits and hospitalizations and increases outpatient asthma monitoring (AM) visits

    Peer support of complex health behaviors in prevention and disease management with special reference to diabetes: systematic reviews

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    Abstract Objectives Examine Peer Support (PS) for complex, sustained health behaviors in prevention or disease management with emphasis on diabetes prevention and management. Data sources and eligibility PS was defined as emotional, motivational and practical assistance provided by nonprofessionals for complex health behaviors. Initial review examined 65 studies drawn from 1442 abstracts identified through PubMed, published 1/1/2000–7/15/2011. From this search, 24 reviews were also identified. Extension of the search in diabetes identified 30 studies published 1/1/2000–12/31/2015. Results In initial review, 54 of all 65 studies (83.1%) reported significant impacts of PS, 40 (61.5%) reporting between-group differences and another 14 (21.5%) reporting significant within-group changes. Across 19 of 24 reviews providing quantifiable findings, a median of 64.5% of studies reviewed reported significant effects of PS. In extended review of diabetes, 26 of all 30 studies (86.7%) reported significant impacts of PS, 17 (56.7%) reporting between-group differences and another nine (30.0%) reporting significant within-group changes. Among 19 of these 30 reporting HbA1c data, average reduction was 0.76 points. Studies that did not find effects of PS included other sources of support, implementation or methodological problems, lack of acceptance of interventions, poor fit to recipient needs, and possible harm of unmoderated PS. Conclusions Across diverse settings, including under-resourced countries and health care systems, PS is effective in improving complex health behaviors in disease prevention and management including in diabetes

    Improving adherence to surveillance and screening recommendations for people with colorectal cancer and their first degree relatives: a randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Colorectal cancer (CRC) is among the leading causes of cancer-related morbidity and mortality worldwide. Despite clinical practice guidelines to guide surveillance care for those who have completed treatment for this disease as well as screening for first degree relatives of people with CRC, the level of uptake of these recommendations remains uncertain. If outcomes for both patients and their families are to be improved, it is important to establish systematic and cost-effective interventions to improve adherence to guideline recommendations for CRC surveillance and screening.</p> <p>Methods/Design</p> <p>A randomized controlled trial will be used to test the effectiveness of a print-based intervention to improve adherence to colonoscopy surveillance among people with CRC and adherence to CRC screening recommendations among their first degree relatives (FDRs). People diagnosed with CRC in the past 10 months will be recruited through a population-based cancer registry. Consenting participants will be asked if their first degree relatives might also be willing to participate in the trial. Information on family history of CRC will be obtained from patients at baseline. Patients and their families will be randomized to either minimal ethical care or the print-based intervention. The print-based intervention for FDRs will be tailored to the participant's level of risk of CRC as determined by the self-reported family history assessment. Follow up data on surveillance and screening participation will be collected from patients and their FDRs respectively at 12, 24 and 36 months' post recruitment. The primary analyses will relate to comparing levels of guideline adherence in usual care group versus print-based group in the patient sample and the FDR sample respectively.</p> <p>Discussion</p> <p>Results of this study will provide contribute to the evidence base about effective strategies to a) improve adherence to surveillance recommendation for people with CRC; and b) improve adherence to screening recommendation for FDRs of people with CRC. The use of a population-based cancer registry to access the target population may have significant advantages in increasing the reach of the intervention.</p> <p>Trial registration</p> <p>This trial is registered with the Australian and New Zealand Clinical Trials Registry Registration Number (ACTRN): <a href="http://www.anzctr.org.au/ACTRN12609000628246">ACTRN12609000628246</a>.</p

    Lifestyle change in Kerala, India: needs assessment and planning for a community-based diabetes prevention trial

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    Abstract Background Type 2 Diabetes Mellitus (T2DM) has become a major public health challenge in India. Factors relevant to the development and implementation of diabetes prevention programmes in resource-constrained countries, such as India, have been under-studied. The purpose of this study is to describe the findings from research aimed at informing the development and evaluation of a Diabetes Prevention Programme in Kerala, India (K-DPP). Methods Data were collected from three main sources: (1) a systematic review of key research literature; (2) a review of relevant policy documents; and (3) focus groups conducted among individuals with a high risk of progressing to diabetes. The key findings were then triangulated and synthesised. Results Prevalence of risk factors for diabetes is very high and increasing in Kerala. This situation is largely attributable to rapid changes in the lifestyle of people living in this state of India. The findings from the systematic review and focus groups identified many environmental and personal determinants of these unhealthy lifestyle changes, including: less than ideal accessibility to and availability of health services; cultural values and norms; optimistic bias and other misconceptions related to risk; and low expectations regarding one’s ability to make lifestyle changes in order to influence health and disease outcomes. On the other hand, there are existing intervention trials conducted in India which suggests that risk reduction is possible. These programmes utilize multi-level strategies including mass media, as well as strategies to enhance community and individual empowerment. India’s national programme for the prevention and control of major non-communicable diseases (NCD) also provide a supportive environment for further community-based efforts to prevent diabetes. Conclusion These findings provide strong support for undertaking more research into the conduct of community-based diabetes prevention in the rural areas of Kerala. We aim to develop, implement and evaluate a group-based peer support programme that will address cultural and family determinants of lifestyle risks, including family decision-making regarding adoption of healthy dietary and physical activity patterns. Furthermore, we believe that this approach will be feasible, acceptable and effective in these communities; with the potential for scale-up in other parts of India

    A peer-support lifestyle intervention for preventing type 2 diabetes in India: A cluster-randomized controlled trial of the Kerala Diabetes Prevention Program.

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    BACKGROUND: The major efficacy trials on diabetes prevention have used resource-intensive approaches to identify high-risk individuals and deliver lifestyle interventions. Such strategies are not feasible for wider implementation in low- and middle-income countries (LMICs). We aimed to evaluate the effectiveness of a peer-support lifestyle intervention in preventing type 2 diabetes among high-risk individuals identified on the basis of a simple diabetes risk score. METHODS AND FINDINGS: The Kerala Diabetes Prevention Program was a cluster-randomized controlled trial conducted in 60 polling areas (clusters) of Neyyattinkara taluk (subdistrict) in Trivandrum district, Kerala state, India. Participants (age 30-60 years) were those with an Indian Diabetes Risk Score (IDRS) ≥60 and were free of diabetes on an oral glucose tolerance test (OGTT). A total of 1,007 participants (47.2% female) were enrolled (507 in the control group and 500 in the intervention group). Participants from intervention clusters participated in a 12-month community-based peer-support program comprising 15 group sessions (12 of which were led by trained lay peer leaders) and a range of community activities to support lifestyle change. Participants from control clusters received an education booklet with lifestyle change advice. The primary outcome was the incidence of diabetes at 24 months, diagnosed by an annual OGTT. Secondary outcomes were behavioral, clinical, and biochemical characteristics and health-related quality of life (HRQoL). A total of 964 (95.7%) participants were followed up at 24 months. Baseline characteristics of clusters and participants were similar between the study groups. After a median follow-up of 24 months, diabetes developed in 17.1% (79/463) of control participants and 14.9% (68/456) of intervention participants (relative risk [RR] 0.88, 95% CI 0.66-1.16, p = 0.36). At 24 months, compared with the control group, intervention participants had a greater reduction in IDRS score (mean difference: -1.50 points, p = 0.022) and alcohol use (RR 0.77, p = 0.018) and a greater increase in fruit and vegetable intake (≥5 servings/day) (RR 1.83, p = 0.008) and physical functioning score of the HRQoL scale (mean difference: 3.9 score, p = 0.016). The cost of delivering the peer-support intervention was US$22.5 per participant. There were no adverse events related to the intervention. We did not adjust for multiple comparisons, which may have increased the overall type I error rate. CONCLUSIONS: A low-cost community-based peer-support lifestyle intervention resulted in a nonsignificant reduction in diabetes incidence in this high-risk population at 24 months. However, there were significant improvements in some cardiovascular risk factors and physical functioning score of the HRQoL scale. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Registry ACTRN12611000262909
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