189 research outputs found

    First-Principle Investigations of (Ti1-xVx)(2)FeGa.lloys. A Study on Structural, Magnetic, Electronic, and Elastic Properties

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    The structural, magnetic, electronic and elastic properties of ternary and quaternary (Ti1-xVx)(2)FeGa alloys with inverse-Heusler (XA) structure were investigated at x = 0, 0.25, 0.50, 0.75, and 1. The crystal structures of (Ti1 - xVx)(2)FeGa compounds are cubic (space group: F (3) over barm) with Hg2CuTi prototype for x = 0 and 1. At x = 0.5 the structure is also cubic (space group: F (3) over barm) with LiMgPdSn protype, while it is tetragonal (space group: P m2) at x = 0.25 and 0.75. Calculated optimized lattice parameters (a and c), bulk modulus (B), and elastic constants (C-ij) are consistent with the available data in the literature. Total and partial magnetic moments of (Ti1 - xVx)(2)FeGa alloys were obtained. An increase in the total magnetic moment values were observed upon addition of V to the Ti2FeGa alloy. From spin polarized band calculations, Ti2FeGa, (Ti0.75V0.25)(2)FeGa, TiVFeGa, and V2FeGa have a minority-spin energy gap of 0.65, 0.38, 0.83, and 0.64 eV, respectively, and they are guessed as half-metallic ferromagnets. According to the results of second-order elastic constants, these compounds met the Born mechanical stability criteria. In addition, according to Pugh criteria, it was found that they have a ductile structure and show anisotropic behavior

    Investigation of Polishing Abilities of Undergraduates and Postgraduates by Using Various Systems on Composite Materials

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    Background: The purpose of dental education is to enable students to gain the knowledge and skills to provide the best service to their patients upon graduation. In order to achieve this, students need to work with a sufficient number of cases and use current materials throughout their education. Aim: The aim of this in vitro study, conducted in 2017, was to examine the surface roughness of two types of composites prepared with different polishing systems, constructed by either undergraduate or doctoral students. Methods: Bulk-fill (Filtek Bulk Fill Posterior) and nano-hybrid (Ceram.x One Universal) composites were polished using single-step (OneGloss Set) and multi-step (Sof-Lex System) systems. The finishing and polishing procedures were performed by ten dental undergraduate students and ten doctoral students. Average surface roughness values (Ra, µm) were measured using a profilometer. Data were analyzed using the Wilcoxon signed-rank test (α = 0.05). Results: No statistically significant differences in Ra values were noted between operators with different levels of experience. Surface roughness was higher in the samples prepared using the single-step system than in those prepared using the multi-step system for both sample types tested in this study. Conclusion: Practitioner ability does not affect the performance of polishing systems. Regardless of the composite type, the single-step polishing system produces rougher surfaces than the multi-step system

    The effect of socio-demographic factors on mental health and addiction high-cost use : a retrospective, population-based study in Saskatchewan

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    Objective: A small proportion of the population accounts for the majority of healthcare costs. Mental health and addiction (MHA) patients are consistently high-cost. We aimed to delineate factors amenable to public health action that may reduce high-cost use among a cohort of MHA clients in Saskatoon, Saskatchewan. Methods: We conducted a population-based retrospective cohort study. Administrative health data from fiscal years (FY) 2009–2015, linked at the individual level, were analyzed (n = 129,932). The outcome of interest was ≥ 90th percentile of costs for each year under study (‘persistent high-cost use’). Descriptive analyses were followed by logistic regression modelling; the latter excluded long-term care residents. Results: The average healthcare cost among study cohort members in FY 2009 was ~ 2300;forhighcostusersitwas 2300; for high-cost users it was ~ 19,000. Individuals with unstable housing and hospitalization(s) had increased risk of persistent high-cost use; both of these effects were more pronounced as comorbidities increased. Patients with schizophrenia, particularly those under 50 years old, had increased probability of persistent high-cost use. The probability of persistent high-cost use decreased with good connection to a primary care provider; this effect was more pronounced as the number of mental health conditions increased. Conclusion: Despite constituting only 5% of the study cohort, persistent high-cost MHA clients (n = 6455) accounted for ~ 35% of total costs. Efforts to reduce high-cost use should focus on reduction of multimorbidity, connection to a primary care provider (particularly for those with more than one MHA), young patients with schizophrenia, and adequately addressing housing stability

    FORMACIONES ANORMALES EN FORAMINÍFEROS PENERÓPLIDOS: UNIÓN DE PENEROPLIS- COSCINOSPIRA

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    A diverse and rich foraminifer fauna has been observed in core and grab samples obtained from Ayvalık (North Aegean coast of Turkey) and Antalya (Southwestern Turkey). Morphologically abnormal individuals of Peneroplis pertusus (Forskål) and P. planatus (Fichtel & Moll) showing Coscinospira characteristics were commonly observed in these sediment samples. Previous findings from Çeşme (East Aegean Sea) indicate that such anomalies in peneroplids are unrare events. The aim of this study is to determine the possible causes of this abnormal test development. Gametes and juveniles of different species of peneroplids may fuse to form such aberrant morphologies. On the other hand, the clusters of Amphicoryna spp. with two or three individuals observed in the Pacific and in the Mediterranean partially support the idea of colony formation.Se ha observado una rica y variada fauna de foraminíferos en muestras obtenidas con dragas y core en Ayvalık (costa norte del Egeo en Turquía) y Antalia (suroeste de Turquía). Frecuentemente se obtuvieron individuos morfológicamente anormales de Peneroplis pertusus (Forskål) y P. planatus (Fichtel & Moll), los cuales mostraban características de Coscinospira. Datos anteriores, obtenidos en Çeşme (este del Mar Egeo), indican que este tipo de anomalías no son raros en peneróplidos. El objetivo de este estudio es determinar las posibles causas del desarrollo anómalo. Los gametos y juveniles de diferentes especies de peneróplidos pueden fundirse en morfologías aberrantes. Por otro lado, las racimos de Amphicoryna spp. con dos o tres individuos, observados en el Pacífico y el Mediterráneo, apoyan, en parte, la idea de formación de colonia

    Diabetes-related molecular signatures in infrared spectra of human saliva

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    WOS: 000290261500001PubMed ID: 20630088Background: There is an ongoing need for improvements in non-invasive, point-of-care tools for the diagnosis and prognosis of diabetes mellitus. Ideally, such technologies would allow for community screening. Methods: In this study, we employed infrared spectroscopy as a novel diagnostic tool in the prediction of diabetic status by analyzing the molecular and sub-molecular spectral signatures of saliva collected from subjects with diabetes (n = 39) and healthy controls (n = 22). Results: Spectral analysis revealed differences in several major metabolic components - lipid, proteins, glucose, thiocyanate and carboxylate - that clearly demarcate healthy and diseased saliva. The overall accuracy for the diagnosis of diabetes based on infrared spectroscopy was 100% on the training set and 88.2% on the validation set. Therefore, we have established that infrared spectroscopy can be used to generate complex biochemical profiles in saliva and identify several potential diabetes-associated spectral features. Conclusions: Infrared spectroscopy may represent an appropriate tool with which to identify novel diseases mechanisms, risk factors for diabetic complications and markers of therapeutic efficacy. Further study into the potential utility of infrared spectroscopy as diagnostic and prognostic tool for diabetes is warranted

    Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

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    Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

    Burden of disease attributable to risk factors in European countries: a scoping literature review

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    Objectives: Within the framework of the burden of disease (BoD) approach, disease, and injury burden estimates attributable to risk factors are a useful guide for policy formulation and priority setting in disease prevention. Considering the important differences in methods, and their impact on burden estimates, we conducted a scoping literature review to: (1) map the BoD assessments including risk factors performed across Europe, and (2) identify the methodological choices in comparative risk assessment (CRA) and risk assessment methods. Methods: We searched multiple literature databases, including grey literature websites, and targeted public health agencies' websites. Results: A total of 113 studies were included in the synthesis and further divided into independent BoD assessments (54 studies) and studies linked to the Global Burden of Disease (59 papers). Our results showed that the methods used to perform CRA varied substantially across independent European BoD studies. While there were some methodological choices that were more common than others, we did not observe patterns in terms of country, year, or risk factor. Each methodological choice can affect the comparability of estimates between and within countries and/or risk factors since they might significantly influence the quantification of the attributable burden. From our analysis, we observed that the use of CRA was less common for some types of risk factors and outcomes. These included environmental and occupational risk factors, which are more likely to use bottom-up approaches for health outcomes where disease envelopes may not be available. Conclusions: Our review also highlighted misreporting, the lack of uncertainty analysis, and the under-investigation of causal relationships in BoD studies. Development and use of guidelines for performing and reporting BoD studies will help understand differences, and avoid misinterpretations thus improving comparability among estimates.info:eu-repo/semantics/publishedVersio

    a review of methodological design choices

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    Publisher Copyright: © 2023 Cambridge University Press. All rights reserved.This systematic literature review aimed to provide an overview of the characteristics and methods used in studies applying the Disability-Adjusted Life Years (DALY) concept for infectious diseases within European Union (EU)/European Economic Area (EEA)/European Free Trade Association (EFTA) countries and the United Kingdom. Electronic databases and grey literature were searched for articles reporting the assessment of DALY and its components. We considered studies in which researchers performed DALY calculations using primary epidemiological data input sources. We screened 3,053 studies of which 2,948 were excluded and 105 studies met our inclusion criteria. Of these studies, 22 were multi-country and 83 were single-country studies, of which 46 were from the Netherlands. Food- and water-borne diseases were the most frequently studied infectious diseases. Between 2015 and 2022, the number of burden of infectious disease studies was 1.6 times higher compared to that published between 2000 and 2014. Almost all studies (97%) estimated DALYs based on the incidence- and pathogen-based approach and without social weighting functions; however, there was less methodological consensus with regards to the disability weights and life tables that were applied. The number of burden of infectious disease studies undertaken across Europe has increased over time. Development and use of guidelines will promote performing burden of infectious disease studies and facilitate comparability of the results.publishersversionepub_ahead_of_prin

    Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

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    Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

    Impact of laboratory test use strategies in a Turkish hospital

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    Objectives: Eliminating unnecessary laboratory tests is a good way to reduce costs while maintain patient safety. The aim of this study was to define and process strategies to rationalize laboratory use in Ankara Numune Training and Research Hospital (ANH) and calculate potential savings in costs. Methods: A collaborative plan was defined by hospital managers; joint meetings with ANHTA and laboratory professors were set; the joint committee invited relevant staff for input, and a laboratory efficiency committee was created. Literature was reviewed systematically to identify strategies used to improve laboratory efficiency. Strategies that would be applicable in local settings were identified for implementation, processed, and the impact on clinical use and costs assessed for 12 months. Results: Laboratory use in ANH differed enormously among clinics. Major use was identified in internal medicine. The mean number of tests per patient was 15.8. Unnecessary testing for chloride, folic acid, free prostate specific antigen, hepatitis and HIV testing were observed. Test panel use was pinpointed as the main cause of overuse of the laboratory and the Hospital Information System test ordering page was reorganized. A significant decrease (between 12.6-85.0%) was observed for the tests that were taken to an alternative page on the computer screen. The one year study saving was equivalent to 371,183 US dollars. Conclusion: Hospital-based committees including laboratory professionals and clinicians can define hospital based problems and led to a standardized approach to test use that can help clinicians reduce laboratory costs through appropriate use of laboratory test
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