Continuity conditions for Q-Bezier curves of degree n.
Ontology highlight
ABSTRACT:
SUBMITTER: Hu G
PROVIDER: S-EPMC5480091 | biostudies-other | 2017
REPOSITORIES: biostudies-other
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Project description:Wang et al. proposed a method for obtaining elliptic curves with embedding degree 1 for securing critical infrastructures, and presented several elliptic curves generated by their method with torsion points of 160 bits and 189 bits orders. They also presented some experimental results and claimed that their implementation of an elliptic curve generated with their method is faster than an implementation for embedded devices presented by Bertoni et al. In this paper, we point out that the security and efficiency claims given by Wang et al. are flawed. Specifically, we show that it is possible to solve finite field discrete logarithm problems defined over their elliptic curves in practice. On the elliptic curves with torsion points of 160 bits orders generated by Wang et al., their instances of finite field discrete logarithm problems are solved in around 4 hours by using a standard desktop PC. On the torsion points of 189 bits orders, their instances are solved in around 10 days by using two standard desktop PCs. The hardness of the finite field discrete logarithm problems is one of the most important bases of security; therefore, their elliptic curves should not be used for cryptographic purposes.
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Project description:Objectives:Adults with schizophrenia and cardiometabolic conditions may be good candidates for co-management by primary care prescribers and specialists. Associated risks for discontinuity in medication management have not been well-studied. This study examines whether medication adherence, inpatient admissions, and emergency department (ED) visits vary by the number and types of prescribers seen by adults with schizophrenia and cardiometabolic conditions. Methods:This study used a retrospective cohort of 4,223 adult Medicaid enrollees with schizophrenia and hypertension, hyperlipidemia, and/or diabetes from three states in 2009-2010. Logistic regression models were run on outcome variables reflecting medication adherence, ED utilization, and inpatient admissions as a function of the number and types of prescribers. Key findings:Increases in number of psychiatric specialists were associated with better antipsychotic adherence, but decreasing statin adherence. Increases in number of psychiatric specialists were also associated with a higher probability of inpatient admission and ED visits, while increases in number of primary care prescribers were associated with increases in the probability of ED visits. Conclusion:Greater antipsychotic adherence for adults receiving prescriptions from multiple psychiatric specialists was counteracted by lower statin adherence and greater risk of ED and inpatient utilization. This may help inform optimal care models for these complex individuals.
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Project description:BackgroundContinuity of care has been explored largely from academic and service provider perspectives, and in relation to adult patient/client groups. We interviewed parents of children with complex chronic health conditions to examine how their experiences and perceptions of continuity of care fit with these perspectives; and to identify the salient factors in the experience of, and factors contributing to, continuity in this population.MethodsParents of 47 elementary school-aged children with spina bifida, Down syndrome, attention-deficit/hyperactivity disorder, Duchenne muscular dystrophy or cystic fibrosis participated in semi-structured interviews. Parents described and mapped the pattern of their interactions with service providers over time in all domains relevant to their child's health, well-being, and development (medical, rehabilitational, educational, and social supportive services), with particular attention paid to their perceptions of connectedness or coherency in these interactions. Verbatim transcripts were analyzed thematically using a framework approach to impose structure regarding parents' perspectives on continuity of care.ResultsExisting academic concepts of relational, informational and management continuity were all discernable in parents' narratives. A thorough knowledge of the child on the part of service providers emerged as extremely important to parents; such knowledge was underpinned by continuity of personal relationships, principally, and also by written information. For this population, notions of continuity extend to the full range of service providers these children and families need to achieve optimal health status, and are not limited to physicians and nurses. Communication among providers was seen as integral to perceived continuity. Compartmentalization of services and information led to parents assuming a necessary, though at times, uncomfortable, coordinating role. Geographic factors, institutional structures and practices, provider attitudes, and, on occasion, parent preferences and judgments, were all found to create barriers to "seamless" management and provision of care continuity across providers, settings, and sectors.ConclusionsThese findings add new perspectives to the understanding of continuity within chronically ill children's health care. They are relevant to contemporary initiatives to improve continuity of services to children with special health care needs, demonstrate the need for parental support of their important role in maintaining continuity, and suggest avenues for further research.
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Project description:The aims of the present study were to evaluate the extent of continuity of care and to investigate its association with several factors among a sample of outpatients with chronic diseases in Italy. The survey was conducted, using face to face interview, from March to December 2014 in a random sample of 633 outpatients with chronic conditions who were going in cardiology, metabolic disorders, and respiratory ambulatory center of four hospitals. A multivariate ordered logistic regression model was used to identify factors associated with the outpatients continuity of care. The mean of the Bice-Boxerman continuity of care (COC) index related to the entire sample was 0.44, and 27.9%, 58.4%, 13.7% had a low, intermediate, and high value of the index based on the tertiles of the distribution. The results of the ordered logistic regression analysis showed that female patients, those older, those who had a lower score of Katz Index of independence in activities of daily living, those who had a lower Charlson et al. comorbidity score, and those who had no hospitalization in the last year, were significantly more likely to have a higher value of the COC index. Patients who had completed a secondary school education had significantly lower odds of having a high value of COC index in comparison to patients with a college degree educational level. Policy makers and clinicians involved in the care of patients should implement comprehensively and efficiently efforts in order to improve the continuity of care in patients with chronic diseases.
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Project description:BackgroundObesity affects nearly half of adults in the United States and is contributing substantially to a pandemic of obesity-associated chronic conditions such as type 2 diabetes, hypertension, and arthritis. The obesity-associated chronic condition pandemic is particularly severe in low-income, medically underserved, predominantly African-American areas in the southern United States. Little is known regarding the impact of geographic, income, and racial disparities in continuity of care on major health outcomes for patients with obesity-associated chronic conditions.ObjectiveThe aim of this study is to assess, among patients with obesity-associated chronic conditions, and within this group, patients with type 2 diabetes, (1) whether continuity of care is associated with lower overall and potentially preventable emergency department and hospital utilization, (2) the effect of geographic, income, and racial disparities on continuity of care and on health care utilization, (3) whether continuity of care particularly protects individuals at risk for disparities from adverse health outcomes, and (4) whether characteristics of health systems are associated with higher continuity of care and better outcomes.MethodsUsing 2015-2018 data from 4 practice-based research networks participating in the Southern Obesity and Diabetes Coalition, we will conduct a retrospective cohort analysis and distributed meta-analysis. Patients with obesity-associated chronic conditions and with type 2 diabetes will be assessed within each health system, following a standardized study protocol. The primary study outcomes are overall and preventable emergency department visits and hospitalizations. Continuity of care will be calculated at the facility level using a modified version of the Bice-Boxerman continuity of care index. Race will be assessed using electronic medical record data. Residence in a low-income area or a health professional shortage area respectively will be assessed by linking patient residence ZIP codes to the Centers for Medicare & Medicaid Services database.ResultsIn 4 regional health systems across Tennessee, Mississippi, Louisiana, and Arkansas, a total of 53 adult hospitals were included in the study. A total of 147,889 patients with obesity-associated chronic conditions who met study criteria were identified in these health systems, of which 45,453 patients met the type 2 diabetes criteria for inclusion. Results are expected by the end of 2020.ConclusionsThis study should reveal whether health system efforts to increase continuity of care for patients with obesity and diabetes have potential to improve outcomes and reduce costs. Analyzing disparities in continuity of care and their effect on major health outcomes can help demonstrate how to improve care and use of health care resources for vulnerable patients with obesity-associated chronic conditions, and within this group, patients with type 2 diabetes. Better understanding of the association between continuity and health care utilization for these vulnerable populations will contribute to the development of higher-value health systems in the southern United States.International registered report identifier (irrid)DERR1-10.2196/20788.
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Project description:AimTo understand the impact and causes of 'Failure to Attend' (FTA) labelling, of patients with chronic conditions.BackgroundNurse navigators are registered nurses employed by public hospitals in Queensland, Australia, to coordinate the care of patients with multiple chronic conditions, who frequently miss hospital appointments. The role of the nurse navigator is to improve care management of these patients. Evidence for this is measured through improvement in patient self-management of their conditions, a reduction in preventable hospital admissions and compliance with attendance at outpatient clinics. Failure to attend (FTA) is one measure of hospital utilisation, identifying outpatient appointments that are cancelled or not attended.MethodThe cohort for this study was patients with multiple chronic conditions, and nurse navigators coordinating their care. Data describing the concept of FTA were thematically analysed twelve months into this three year evaluation.ResultsAlthough the patient is blamed for failing to attend appointments, the reasons appear to be a mixture of systems error/miscommunication between the patient and the health services or social reasons impacting on patient's capacity to attend. Themes emerging from the data were: access barriers; failure to recognise personal stigma of FTA; and bridging the gap.ConclusionThe nurse navigators demonstrate their pivotal role in engaging with outpatient services to reduce FTAs whilst helping patients to become confident in dealing with multiple appointments. There are many reasons why a patient is unable to attend a scheduled appointment. The phrase 'Failure to Attend' has distinctly negative connotations and can lead to a sense of blame and shame for those with complex chronic needs. We propose the use of the neutral phrase "appointment did not proceed" to replace FTA.Implications for nursing managementThis article advocates for further consideration of collaborative models that engage the patient in their care journey and for consideration of the language used within the outpatient acute hospital setting, proposing the term 'appointment did not proceed.'
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