7,572 research outputs found

    Predicting Intermediate Storage Performance for Workflow Applications

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    Configuring a storage system to better serve an application is a challenging task complicated by a multidimensional, discrete configuration space and the high cost of space exploration (e.g., by running the application with different storage configurations). To enable selecting the best configuration in a reasonable time, we design an end-to-end performance prediction mechanism that estimates the turn-around time of an application using storage system under a given configuration. This approach focuses on a generic object-based storage system design, supports exploring the impact of optimizations targeting workflow applications (e.g., various data placement schemes) in addition to other, more traditional, configuration knobs (e.g., stripe size or replication level), and models the system operation at data-chunk and control message level. This paper presents our experience to date with designing and using this prediction mechanism. We evaluate this mechanism using micro- as well as synthetic benchmarks mimicking real workflow applications, and a real application.. A preliminary evaluation shows that we are on a good track to meet our objectives: it can scale to model a workflow application run on an entire cluster while offering an over 200x speedup factor (normalized by resource) compared to running the actual application, and can achieve, in the limited number of scenarios we study, a prediction accuracy that enables identifying the best storage system configuration

    Prevalance of Apple Scab in Different Lebanese Regions and the Study of Isolate Resistance to two Fungicides

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    Fatigue and TSH Levels in Hypothyroid Patients

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    Background. Fatigue is often the complaint that initiates thyroid function investigation. Most available data related to fatigue and hypothyroidism involved patients with subclinical hypothyroidism where fatigue was not the primary outcome. This study investigated the association between TSH levels and fatigue and if there was a target TSH interval that was associated with lower incidence of fatigue in patients with hypothyroidism. Methods. An analytic, retrospective cohort study design assessed the relationship between TSH levels and fatigue. All adult patients at one endocrinology clinic who were diagnosed with hypothyroidism between January 1, 2006 and December 31, 2007 were included. Diagnoses were confirmed by biochemical testing. Data were abstracted from the clinic’s electronic medical record. Fatigue status was self-reported by the subject during examination by the endocrinologist. Fatigue status and TSH levels were obtained twice: at diagnosis and during the first follow-up visit. Results. A total of 135 patients met the inclusion criteria. After treatment, all patients had reductions in TSH levels. Those subjects reporting relief from fatigue tended to be males (p = 0.003), had lower TSH levels at follow-up (p < 0.001), had larger TSH differences from baseline (p =0.007), and had a primary diagnosis of acquired hypothyroidism (p < 0.001). Females were 2.9 times more likely to report persistent fatigue than males. Patients with primary diagnosis of thyroiditis were 3 times more likely to report persistent fatigue than those with acquired hypothyroidism. Conclusions. The observed relief from fatigue after treatment correlated with a higher TSH reduction compared to patients with persistent fatigue. It was unclear if fatigue relief was related to the level of TSH reduction (TSH difference) or to a lower absolute TSH level reached after treatment

    Readability and content analysis of lifestyle education resources for weight management in Australian general practice

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    © 2016 El-Haddad et al. Background: Weight management education is one of the key strategies to assist patients to manage their weight. Educational resources provide an important adjunct in the chain of communication between practitioners and patients. However, one in five Australian adults has low health literacy. The purpose of this study was to assess the readability and analyse the content of weight management resources. Methods: This study is based on the analysis of 23 resources found in the waiting rooms of ten Sydney-based general practices and downloaded from two clinical software packages used at these practices. The reading grade level of these resources was calculated using the Flesch Reading Ease, Flesch-Kincaid Grade Level, Fry Readability Graph, and the Simplified Measure of Gobbledygook. Resources' content was analysed for the presence of dietary, physical activity, and behaviour change elements, as recommended by the Clinical practice guidelines for the management of overweight and obesity in adults, adolescents, and children in Australia. Results: The resources' average reading grade level was for a 10th grader (9.5 ± 1.8). These findings highlight that the average reading grade level was two grades higher than the recommended reading grade level for health education resources of 8th grade level or below. Seventy percent of resources contained dietary and behaviour change elements. Physical activity was included in half of the resources. Two messages were identified to be inconsistent with the guidelines and three messages had no scientific basis. Conclusion: A body of evidence now exists that supports the need to develop evidence-based education resources for weight management that place low demand on literacy, without compromising content accuracy. The findings from this study suggest that there is significant room for improvement in the educational resources provided in general practices

    Methylene tetrahydrofolate reductase, transforming growth factor-β1 and lymphotoxin-α genes polymorphisms and susceptibility to rheumatoid arthritis

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    AbstractBackgroundRheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition.ObjectivesThe aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677 T and A1298 C), transforming growth factor-β1 (TGF-β1 T869 C) and lymphotoxin-α (LT-α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor-alpha (TNF-α), B-Cell Activating Factor (BAFF), and osteopontin.MethodsA total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677 T and A1298 C, TGF-β1 T869 C and LT-α A252G polymorphisms using a methodology based on PCR-RFLP. Also serum levels of TNF-α, osteopontin and BAFF were measured by ELISA kits.ResultsThe CT genotype and T allele of MTHFR C677 T and GG genotype and G allele of LT-α A252G are associated with the risk of RA and with higher levels of the pro-inflammatory cytokine, TNF-α in patients with rheumatoid arthritis.ConclusionOur findings suggest that there is association between MTHFR C677 T and LT-α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population

    Polimorfismos dos genes metilenotetrahidrofolato redutase, fator de crescimento transformador β1 e linfotoxina‐α e susceptibilidade à artrite reumatoide

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    ResumoAntecedentesA artrite reumatoide é uma doença autoimune amplamente prevalente com sugerida predisposição genética.ObjetivosDetectar o padrão de polimorfismo dos genes metilenotetrahidrofolato redutase (MTHFR C677T e A1298C), fator de crescimento transformador β1 (TGF‐β1 T869C) e linfotoxina‐α (LT‐α A252G) em pacientes com artrite reumatoide e correlacionar esses padrões com a atividade da doença e os níveis séricos de fator de necrose tumoral alfa (TNF‐α), fator ativador de linfócitos B (BAFF) e osteopontina.MétodosForam genotipados 194 indivíduos – 90 controles e 104 com artrite reumatoide – à procura de polimorfismos dos genes MTHFR C677T e A1298C, TGF‐β1 T869C e LT‐α A252G com uma metodologia baseada na PCR‐RFLP. Mensuraram‐se também os níveis séricos de TNF‐α, osteopontina e BAFF com kits de Elisa.ResultadosO genótipo CT e o alelo T do MTHFR C677T e o genótipo GG e alelo G do LT‐α A252G estão associados ao risco de AR e a níveis mais elevados da citocina pró‐inflamatória TNF‐α em pacientes com artrite reumatoide.ConclusãoOs achados do presente estudo sugerem que há associação entre os polimorfismos dos genes MTHFR C677T e LT‐α A252G e um risco aumentado de AR nessa amostra da população egípcia.AbstractBackgroundRheumatoid arthritis is a widely prevalent autoimmune disorder with suggested genetic predisposition.ObjectivesThe aim of this study is to detect the pattern of genetic polymorphism of methylene tetrahydrofolate reductase (MTHFR C677T and A1298C), transforming growth factor‐β1 (TGF‐β1 T869C) and lymphotoxin‐α (LT‐α A252G) in patients having rheumatoid arthritis and correlate these patterns to disease activity and serum levels of tumor necrosis factor‐alpha (TNF‐α), B‐Cell Activating Factor (BAFF), and osteopontin.MethodsA total of 194 subjects, 90 controls and 104 patients with rheumatoid arthritis were genotyped for MTHFR C677T and A1298C, TGF‐β1 T869C and LT‐α A252G polymorphisms using a methodology based on PCR‐RFLP. Also serum levels of TNF‐α, osteopontin and BAFF were measured by ELISA kits.ResultsThe CT genotype and T allele of MTHFR C677T and GG genotype and G allele of LT‐α A252G are associated with the risk of RA and with higher levels of the pro‐inflammatory cytokine, TNF‐α in patients with rheumatoid arthritis.ConclusionOur findings suggest that there is association between MTHFR C677T and LT‐α A252G genes polymorphisms and increased risk of RA in this sample of Egyptian population

    Constraining a hybrid volatility basis-set model for aging of wood-burning emissions using smog chamber experiments : A box-model study based on the VBS scheme of the CAMx model (v5.40)

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    In this study, novel wood combustion aging experiments performed at different temperatures (263 and 288 K) in a ∼ 7 m³ smog chamber were modelled using a hybrid volatility basis set (VBS) box model, representing the emission partitioning and their oxidation against OH. We combine aerosol–chemistry box-model simulations with unprecedented measurements of non-traditional volatile organic compounds (NTVOCs) from a high-resolution proton transfer reaction mass spectrometer (PTR-MS) and with organic aerosol measurements from an aerosol mass spectrometer (AMS). Due to this, we are able to observationally constrain the amounts of different NTVOC aerosol precursors (in the model) relative to low volatility and semi-volatile primary organic material (OMsv_{sv}), which is partitioned based on current published volatility distribution data. By comparing the NTVOC ∕ OMsv_{sv} ratios at different temperatures, we determine the enthalpies of vaporization of primary biomass-burning organic aerosols. Further, the developed model allows for evaluating the evolution of oxidation products of the semi-volatile and volatile precursors with aging. More than 30 000 box-model simulations were performed to retrieve the combination of parameters that best fit the observed organic aerosol mass and O : C ratios. The parameters investigated include the NTVOC reaction rates and yields as well as enthalpies of vaporization and the O : C of secondary organic aerosol surrogates. Our results suggest an average ratio of NTVOCs to the sum of non-volatile and semi-volatile organic compounds of ∼ 4.75. The mass yields of these compounds determined for a wide range of atmospherically relevant temperatures and organic aerosol (OA) concentrations were predicted to vary between 8 and 30 % after 5 h of continuous aging. Based on the reaction scheme used, reaction rates of the NTVOC mixture range from 3.0 × 1011^{-11} to 4. 0 × 1011^{-11} cm³ molec1^{-1} s1^{-1}. The average enthalpy of vaporization of secondary organic aerosol (SOA) surrogates was determined to be between 55 000 and 35 000 J mol1^{-1}, which implies a yield increase of 0.03-0.06 % K1^{-1} with decreasing temperature. The improved VBS scheme is suitable for implementation into chemical transport models to predict the burden and oxidation state of primary and secondary biomass-burning aerosols

    In-cloud processes of methacrolein under simulated conditions – Part 2: Formation of secondary organic aerosol

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    The fate of methacrolein in cloud evapo-condensation cycles was experimentally investigated. To this end, aqueous-phase reactions of methacrolein with OH radicals were performed (as described in Liu et al., 2009), and the obtained solutions were then nebulized and dried into a mixing chamber. ESI-MS and ESI-MS/MS analyses of the aqueous phase composition denoted the formation of high molecular weight multifunctional products containing hydroxyl, carbonyl and carboxylic acid moieties. The time profiles of these products suggest that their formation can imply radical pathways. These high molecular weight organic products are certainly responsible for the formation of secondary organic aerosol (SOA) observed during the nebulization experiments. The size, number and mass concentration of these particles increased significantly with the reaction time: after 22 h of reaction, the aerosol mass concentration was about three orders of magnitude higher than the initial aerosol quantity. The evaluated SOA yield ranged from 2 to 12%. These yields were confirmed by another estimation method based on the hygroscopic and volatility properties of the obtained SOA measured and reported by Michaud et al. (2009). These results provide, for the first time to our knowledge, strong experimental evidence that cloud processes can act, through photooxidation reactions, as important contributors to secondary organic aerosol formation in the troposphere
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