169 research outputs found

    On Optimal Partitioning For Sparse Matrices In Variable Block Row Format

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    The Variable Block Row (VBR) format is an influential blocked sparse matrix format designed to represent shared sparsity structure between adjacent rows and columns. VBR consists of groups of adjacent rows and columns, storing the resulting blocks that contain nonzeros in a dense format. This reduces the memory footprint and enables optimizations such as register blocking and instruction-level parallelism. Existing approaches use heuristics to determine which rows and columns should be grouped together. We adapt and optimize a dynamic programming algorithm for sequential hypergraph partitioning to produce a linear time algorithm which can determine the optimal partition of rows under an expressive cost model, assuming the column partition remains fixed. Furthermore, we show that the problem of determining an optimal partition for the rows and columns simultaneously is NP-Hard under a simple linear cost model. To evaluate our algorithm empirically against existing heuristics, we introduce the 1D-VBR format, a specialization of VBR format where columns are left ungrouped. We evaluate our algorithms on all 1626 real-valued matrices in the SuiteSparse Matrix Collection. When asked to minimize an empirically derived cost model for a sparse matrix-vector multiplication kernel, our algorithm produced partitions whose 1D-VBR realizations achieve a speedup of at least 1.18 over an unblocked kernel on 25% of the matrices, and a speedup of at least 1.59 on 12.5% of the matrices. The 1D-VBR representation produced by our algorithm had faster SpMVs than the 1D-VBR representations produced by any existing heuristics on 87.8% of the test matrices

    Many parameter Hoelder perturbation of unbounded operators

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    If u↩A(u)u\mapsto A(u) is a C0,αC^{0,\alpha}-mapping, for 0<α≀10< \alpha \le 1, having as values unbounded self-adjoint operators with compact resolvents and common domain of definition, parametrized by uu in an (even infinite dimensional) space, then any continuous (in uu) arrangement of the eigenvalues of A(u)A(u) is indeed C0,αC^{0,\alpha} in uu.Comment: LaTeX, 4 pages; The result is generalized from Lipschitz to Hoelder. Title change

    Inhalation health risk assessment of ambient PM2.5 and associated trace elements in Cape Town, South Africa

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    This manuscript was part of the Ph.D. project of Anna Alfeus. Prof Janine Wichmann and Dr. Joyce Shirinde supervised the Ph.D. thesis.DATA AVAILABILITY : The authors are working on other manuscripts with the data, hence the data is not available to the public.Please read abstract in article.The University of Pretoria doctoral bursary, University of Namibia Staff Development office, the AGNES grant office and analysis funding with an NRF grant.https://www.tandfonline.com/loi/bher20hj2023School of Health Systems and Public Health (SHSPH

    Substantial Decrease in Comorbidity 5 Years After Gastric Bypass : A Population-based Study From the Scandinavian Obesity Surgery Registry

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    OBJECTIVE:: To evaluate effect on comorbid disease and weight loss 5 years after Roux-en-Y gastric bypass (RYGB) surgery for morbid obesity in a large nationwide cohort. BACKGROUND:: The number patients having surgical procedures to treat obesity and obesity-related disease are increasing. Yet, population-based, long-term outcome studies are few. METHODS:: Data on 26,119 individuals [75.8% women, 41.0 years, and body mass index (BMI) 42.8?kg/m] undergoing primary RYGB between May 1, 2007 and June 30, 2012, were collected from 2 Swedish quality registries: Scandinavian Obesity Surgery Registry and the Prescribed Drug Registry. Weight, remission of type 2 diabetes mellitus, hypertension, dyslipidemia, depression, and sleep apnea, and changes in corresponding laboratory data were studied. Five-year follow-up was 100% (9774 eligible individuals) for comorbid diseases. RESULTS:: BMI decreased from 42.8?±?5.5 to 31.2?±?5.5?kg/m at 5 years, corresponding to 27.7% reduction in total body weight. Prevalence of type 2 diabetes mellitus (15.5%–5.9%), hypertension (29.7%–19.5%), dyslipidemia (14.0%–6.8%), and sleep apnea (9.6%–2.6%) was reduced. Greater weight loss was a positive prognostic factor, whereas increasing age or BMI at baseline was a negative prognostic factor for remission. The use of antidepressants increased (24.1%–27.5%). Laboratory status was improved, for example, fasting glucose and glycated hemoglobin decreased from 6.1 to 5.4?mmol/mol and 41.8% to 37.7%, respectively. CONCLUSIONS:: In this nationwide study, gastric bypass resulted in large improvements in obesity-related comorbid disease and sustained weight loss over a 5-year period. The increased use of antidepressants warrants further investigation

    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1ÎČ, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1ÎČ innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

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    Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≄ II, EF ≀35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure &lt; 100 mmHg (n = 1127), estimated glomerular filtration rate &lt; 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

    Gender differences in school anger

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    This study examined gender differences in the affective, behavioural, and cognitive components of anger in 102 students completing their first year of high school. Results supported not only the hypothesis that girls and boys do not differ in their experience (affective) of anger but also the belief that girls are more likely to positively express (behavioural) their anger than boys. Additionally, results supported the expectation that boys were more hostile (cognitive) towards school than girls. Suggestions for future research and the relevance of the findings for schools are also addressed

    Voices from schools: Listening to students in transition

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    Despite convincing literature to the contrary, the notions of 'transition shock' and the 'storm and stress' of adolescence persist in views on primary-secondary school transfer. This paper reports on the 'voices' of some Australian students as they have anticipatd and experienced primary-secondary transfer. It sets these findings in a broader consideration of transition and reports the views of young adolescents. It suggests that although transfer is an important part of the transition process, the adaptation phase' during which students are adjusting to secondary school, may be the more critical. The paper concludes with some reflections on the implications of this small-scale study

    Comparison of disruptive behaviours in South Australian LOTE and mainstream primary school classrooms

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    The frequencies of disruptive behaviours in students were compared between their respective LOTE (German) and mainstream primary school classrooms. Forty-nine students aged between nine and twelve, from years four to seven, were observed during the study. The overall frequency of disruptive behaviours in German classes was found to be significantly higher than in mainstream classes. Three of the four observed behaviours were also found to be more frequent in German classes. Some suggestions for improving teaching practive and future research have been made

    'Okay girl, it's up to you': a case study of the use of a seizure alert dog to improve the wellbeing of a student with epilepsy

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    The relationship between student well-being and the other vital outcomes of school is unequivocal. Improved outcomes in all aspects of student well-being are positively associated with improved outcomes in all other aspects of schooling. This educational imperative only serves to strengthen and support the moral imperative for schools and schooling to be inclusive, supportive and nurturing in order to maintain and support student well-being. (Fraillon 2005, p. 12
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