1,345 research outputs found

    Land use effects on heavy metal pollution of river sediments in Guilan, southwest of the Caspian sea

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    Studies have showed the River Siahroud is the main contributor to the present pollution of Anzali Wetland in Guilan. Therefore, this study was initiated to evaluate the spatial distribution of metals pollution on the River Siahroud sediments in Guilan. Surfacial river sediment samples along this river were taken during five consecutive seasons at eight sampling stations and analyzed for availability of Fe, Mn, Pb, Zn, Cu, Cr, Cd metals. Canonical correlation demonstrated that the total organic carbon (TOC) was of great importance in co-precipitation of Zn while Cu and Pb were mainly related to hydrous iron oxides. Also, in the interest of pollutant finger printing, factor analysis showed that extractable Zn, Cu, Fe, Cd and Mn were attributed to the present agricultural fields while industrial site of Rasht City was the major contributing factor for the extended levels of Cr in the study area. Moreover, Pb level was mainly relevant to urban land use in Rasht. Cluster analysis demonstrated that there was a rising metal pollution level in the River Siahroud from upstream to downstream suggesting that Anzali Wetland pollution could be highly related to loading of heavy metals by the River Siahroud sediment

    Naked-eye detection of morphine by Au@Ag nanoparticles-based colorimetric chemosensors

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    In this study, we report a novel and facile colorimetric assay based on silver citrate-coated Au@Ag nanoparticles (Au@AgNPs) as a chemosensor for the naked-eye detection of morphine (MOR). The developed optical sensing approach relied on the aggregation of Au@Ag NPs upon exposure to morphine, which led to an evident color variation from light-yellow to brown. Au@Ag NPs have been prepared by two different protocols, using high- and low-power ultrasonic irradiation. The sonochemical method was essential for the sensing properties of the resulting nanoparticles. This facile sensing method has several advantages including excellent stability, selectivity, prompt detection, and cost-effectiveness

    Voltage-controlled Hubbard spin transistor

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    Transistors are key elements for enabling computational hardware in both classical and quantum domains. Here we propose a voltage-gated spin transistor using itinerant electrons in the Hubbard model which acts at the level of single electron spins. Going beyond classical spintronics, it enables the controlling of the flow of quantum information between distant spin qubits. The transistor has two modes of operation, open and closed, which are realized by two different charge configurations in the gate of the transistor. In the closed mode, the spin information between source and drain is blocked while in the open mode we have free spin information exchange. The switching between the modes takes place within a fraction of the operation time which allows for several subsequent operations within the coherence time of the transistor. The system shows good resilience against several imperfections and opens up a practical application for quantum dot arrays

    Effects of diabetes mellitus on health-related quality of life at a tertiary hospital in South Africa: A cross-sectional study

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    Background. Diabetes mellitus (DM) is a chronic metabolic disease that potentially causes debilitating and life-threatening complications, demands a lifestyle change, and has important implications with regard to wellbeing and health-related quality of life (HRQOL).Objectives. To: (i) determine the HRQOL of a sample of patients with type 2 diabetes; (ii) describe the demographics (age, gender, and smoking and alcohol use) of the population studied; (iii) document the following parameters, which are important in determining the control and severity of type 2 diabetes: (a) glycosylated haemoglobin (HbA1c), (b) total amount of insulin required per day (if on insulin therapy), (c) body mass index (BMI), and (d) exercise compliance; (iv) determine whether there was an association between any or all of the above parameters and the HRQOL of these patients; and (v) determine whether coexisting diseases (hypertension (HT) and dyslipidaemia) were present, and compare HRQOL between diabetic patients with and without these diseases.Methods. This was a cross-sectional and descriptive study of 200 patients attending the diabetes clinic at Helen Joseph Hospital, Johannesburg, South Africa. HRQOL assessments were made using the Diabetes 39 (D-39) questionnaire, which patients filled in once consent had been obtained and if they fulfilled the inclusion criteria. Patients’ questionnaire forms were then analysed with regard to their demographics (age and gender), exercise regimen, smoking and alcohol history, employment status, living arrangements, age of diagnosis of DM, and concurrent use of antihypertensive and cholesterol-lowering drugs. The patients’ files were analysed and various clinical parameters were noted (HbA1c, lipogram, BMI, number of insulin units used per day, and whether any antihypertensive and/or lipidlowering drugs were used).Results. There was an association between HRQOL and HbA1c, and between HRQOL and HT and dyslipidaemia.Conclusions. No association was found between HRQOL and other clinical parameters, namely number of insulin units used per day, exercise, BMI, lipogram and the use of oral hypoglycaemic agents. Demographic parameters (age, gender, age at diagnosis, employment status and living arrangements) were also shown to have no impact on HRQOL. We found no association between HRQOL in patients who consumed alcohol and smoked cigarettes and in those who did not

    Floquet-induced localization in long-range many-body systems

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    The fate of many-body localization in long-range interacting systems is not fully settled. For instance, the phase boundary between ergodic and many-body localized regimes is still under debate. Here, we use Floquet dynamics which can induce many-body localization in a clean long-range interacting system through spatio-temporal disorder, which are realized by regular operation of random local rotations. The phase diagram has been determined for two types of uniform and nonuniform long-range couplings. Our Floquet mechanism shows more localizing power than conventional static disorder methods as it pushes the phase boundary in favor of the localized phase. Moreover, our comprehensive long-time simulations provide strong support for obtained results based on static analysis

    Prevalence and pattern of dyslipidaemia in type 2 diabetes mellitus patients at a tertiary care hospital

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    Background: Diabetes mellitus (DM) is a common secondary cause of dyslipidaemia, particularly if glycaemic control is poor, which in turn is an important risk factor for atherosclerosis and coronary artery disease.Objectives: (1) To study the prevalence and pattern of dyslipidaemia in patients with type 2 DM. (2) To determine the relationship (if any) between HbA1C and the lipid profile in type 2 diabetic patients.Methods: This was a cross-sectional study done in 200 type 2 diabetic patients  attending the Diabetic Clinic at the Helen Joseph Hospital. Patients suffering from other known causes of secondary dyslipidaemia were excluded. Each patient’s  HbA1C and lipid profile results were recorded from their clinic files. The lipid profile included total cholesterol (TC), triglyceride (TG), high-density lipoprotein  cholesterol (HDL-C) and calculated low-density lipoprotein cholesterol (LDL-C). Patients with one or more of the above parameters outside the targets recommended by the 2012 South African Dyslipidaemia Guidelines were considered to have uncontrolled dyslipidaemia.Results: Of the 200 type 2 DM patients studied, 86 (43%) were male and 114 (57%) female. Despite all patients being treated with lipid-lowering therapy  (simvastatin at a mean daily dose of 20 mg), 187 patients (93.5%) did not achieve all their lipid targets. The most prevalent lipid parameter not at target was an LDL-C of ≥ 1.8 mmol/l in nearly 80% of patients. The most common pattern of  dyslipidaemia was a combined dyslipidaemia (any two abnormal lipid parameters) affecting a total of 82 out of the 187 patients (43.8%) not reaching recommended  targets. No significant relationship was found between HbA1C and any of the lipid parameters.Conclusion: The vast majority of the type 2 diabetic patients studied had  dyslipidaemia not meeting recommended targets, despite the use of lipid-lowering therapy in all patients. There is a need for more intensive lipid-lowering therapy, particularly statin therapy in patients with dyslipidaemia. Measures aimed at  combating obesity and other lifestyle-related risk factors are also vital and need to be implemented for effectively controlling dyslipidaemia and reducing the burden of CVD.Keywords: combined dyslipidaemia, LDL, lipid target

    Dynamics of entanglement of bosonic modes on symmetric graphs

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    We investigate the dynamics of an initially disentangled Gaussian state on a general finite symmetric graph. As concrete examples we obtain properties of this dynamics on mean field graphs of arbitrary sizes. In the same way that chains can be used for transmitting entanglement by their natural dynamics, these graphs can be used to store entanglement. We also consider two kinds of regular polyhedron which show interesting features of entanglement sharing.Comment: 14 pages, 11 figures, Accepted for publication in Physics Letters

    Satisfaction with hearing aids among aged patients with different degrees of hearing loss and length of daily use

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    Background and Objectives: The evaluation of subjective benefits and positive effects of hearing aids in daily is important for measuring the treatment outcome. The aim of this project was to investigate the degree of satisfaction of aged users with their hearing aids using the Satisfaction with Amplification in Daily Life (SADL) scale, which emphasizes non-auditory factors contributing to satisfaction as well as benefit. Subjects and Methods: The Persian version of SADL scale was completed by 40 patients who received monaural hearing aid fitting at south of the Iran from December 2013 and March 2014. SADL subscales of the SADL were evaluated according to the type and degree of hearing loss, the pure tone audiogram pattern and shape and type of the hearing aid. Results: The results associated with the SADL subscales revealed a greater satisfaction associated with the Positive Effect and Service and Costs subscales. Subjects with different degree of hearing loss were very satisfied in terms of positive effect subscale. Conclusions: Participants reported a considerable level of satisfaction with their hearing aids. Appropriate guidance for using hearing aids and spending more time for counseling can improve the satisfaction level of this age group. © 2015 The Korean Audiological Society

    Taxon abundance, diversity, co-occurrence and network analysis of the ruminal microbiota in response to dietary changes in dairy cows

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    We thank Mari Talvisilta and the staff in the metabolism unit at Natural Resources Institute Finland for technical support, care of experimental animals and assistance in sample collection. We thank Paula Lidauer for ruminal cannulation surgeries, Richard Hill from Aberystwyth University, UK for performing qPCR and Aurélie Bonin from Laboratoire d'Ecologie Alpine, CNRS, France for preparing archaea amplicon libraries for sequencing. Kevin J. Shingfield passed away before the submission of the final version of this manuscript. Ilma Tapio accepts responsibility for the integrity and validity of the data collected and analyzed. Funding: Study was funded by the Finnish Ministry of Agriculture and Forestry as part of the GreenDairy Project (Developing Genetic and Nutritional Tools to Mitigate the Environmental Impact of Milk Production; Project No. 2908234). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    Concurrence in Disordered Systems

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    Quantum systems exist at finite temperatures and are likely to be disordered to some level. Since applications of quantum information often rely on entanglement, we require methods which allow entanglement measures to be calculated in the presence of disorder at non-zero temperatures. We demonstrate how the disorder averaged concurrence can be calculated using thermal many-body perturbation theory. Our technique can also be applied to other entanglement measures. To illustrate, we find the disorder averaged concurrence of an XX spin chain. We find that concurrence can be increased by disorder in some parameter regimes.Comment: 14 pages, 5 figure
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