36 research outputs found

    Young LMC clusters: the role of red supergiants and multiple stellar populations in their integrated light and CMDs

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    The optical integrated spectra of three LMC young stellar clusters (NGC 1984, NGC 1994 and NGC 2011) exhibit concave continua and prominent molecular bands which deviate significantly from the predictions of single stellar population (SSP) models. In order to understand the appearance of these spectra, we create a set of young stellar population (MILES) models, which we make available to the community. We use archival International Ultraviolet Explorer integrated UV spectra to independently constrain the cluster masses and extinction, and rule out strong stochastic effects in the optical spectra. In addition, we also analyze deep colour-magnitude diagrams of the clusters to provide independent age determinations based on isochrone fitting. We explore hypotheses including age-spreads in the clusters, a top-heavy initial mass function, different SSP models and the role of red supergiant stars (RSG). We find that the strong molecular features in the optical spectra can only be reproduced by modeling an increased fraction of about 20 per cent by luminosity of RSG above what is predicted by canonical stellar evolution models. Given the uncertainties in stellar evolution at Myr ages, we cannot presently rule-out the presence of Myr age-spreads in these clusters. Our work combines different wavelengths as well as different approaches (resolved data as well as integrated spectra for the same sample) in order to reveal the complete picture. We show that each approach provides important information but in combination can we better understand the cluster stellar populations.Comment: Accepted for publication in MNRA

    A Cost Benefit Calculator for RFID Implementations in the Apparel Retail Industry

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    The apparel retail industry is on the one hand facing challenges from increasing competition, consolidations, and thus increasing pressure to reduce costs. On the other hand, customers are getting more demanding, resulting in shorter fashion cycles, and demands for new customer experience. RFID technology is supposed to raise efficiency and to enable innovative customer service offerings. Besides cost savings, benefits are expected to arise from newly designed RFID applications and customer insights from analyses of shop floor data. Recently, apparel retailers started to investigate this technology, resulting in several trials and pilots world-wide. However, the business case of RFID in the apparel retail industry is not clear. Based on the findings of a real-world deployment, our contribution presents a cost-benefit calculator that is specifically designed to meet the requirements of apparel retail industry RFID implementations

    Relation between early stages of diabetic retinopathy and early stages of diabetic kidney disease in patients with type 2 diabetes in Egypt

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    Background. Diabetes mellitus is a pandemic disease. Type 2 diabetes (T2DM) is the most common type. Diabetic retinopathy (DR) and diabetic kidney disease (DKD) are disabling chronic complications. The relation between both is not yet well-established in T2DM. Egypt is considered one of the top ten countries re- garding the prevalence of diabetes that makes diabetes and its complications a major health problem. This encouraged us to conduct this research.  Materials and methods. The study included 79 patients with T2DM divided into two groups according to the presence of retinopathy. Both groups were subdivided according to urinary albumin to creatinine ratio (UACR) into normoalbuminuric and albuminuric subgroups. Retinopathy group was further subdivided according to severity of retinopathy into mild, moderate and severe non-proliferative DR (NPDR). Statistical analysis was done and relation between the severity of retinopathy and UACR was studied.  Results. Patients with retinopathy had significantly higher diabetes duration and UACR than non retinopathy group. Also in subgroups of normoalbuminuria and albuminuria, retinopathy group was significantly higher regarding the same parameters. On subdividing the retinopathy group according to severity, severe NPDR group had significantly higher UACR. The severity of DR was significantly positively correlated with UACR.  Conclusions. The present study identified a significantly positive correlation between early stages of DR and UACR in patients with T2DM in Egypt. Not all cases of DR had DKD especially in early stages and also not all cases of DKD are associated with the presence of DR in T2DM.   Background. Diabetes mellitus is a pandemic disease. Type 2 diabetes (T2DM) is the most common type. Diabetic retinopathy (DR) and diabetic kidney disease (DKD) are disabling chronic complications. The relation between both is not yet well-established in T2DM. Egypt is considered one of the top ten countries re- garding the prevalence of diabetes that makes diabetes and its complications a major health problem. This encouraged us to conduct this research.  Materials and methods. The study included 79 patients with T2DM divided into two groups according to the presence of retinopathy. Both groups were subdivided according to urinary albumin to creatinine ratio (UACR) into normoalbuminuric and albuminuric subgroups. Retinopathy group was further subdivided according to severity of retinopathy into mild, moderate and severe non-proliferative DR (NPDR). Statistical analysis was done and relation between the severity of retinopathy and UACR was studied.  Results. Patients with retinopathy had significantly higher diabetes duration and UACR than non retinopathy group. Also in subgroups of normoalbuminuria and albuminuria, retinopathy group was significantly higher regarding the same parameters. On subdividing the retinopathy group according to severity, severe NPDR group had significantly higher UACR. The severity of DR was significantly positively correlated with UACR.  Conclusions. The present study identified a significantly positive correlation between early stages of DR and UACR in patients with T2DM in Egypt. Not all cases of DR had DKD especially in early stages and also not all cases of DKD are associated with the presence of DR in T2DM. 

    Growing and laying performance of two different-plumage color Japanese quail varieties supplemented with corn silk in their diet

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    The current study aimed to investigate the dietary supplementation effect of corn silk (CS) on performance and blood chemistry of brown and whitefeathered quails during the grower and layer periods. Japanese quails of brown and white-feathered color (180 birds/variety at 2 wks old) were randomly allotted into three groups with 3 replicates each (n = 20 birds/ replicate). Corn silk powder (CS) was supplemented to the basal diet at 0, 1, and 2% of the diet for each quail variety for 1-month growing period, then continued for another 6-wk laying period to assess the egg production and egg quality characteristics. CS supplementation at 1% and 2% for brown and white-feathered quails respectively improved their growth performance (body weight and weight gain), carcass yield, and intestinal villi length with increasing feed consumption but without changes in feed conversion ratio. In both quail varieties, CS addition had a hypolipidemic effect, confirmed by lowering serum triglyceride (TG), cholesterol (CHO), and low density lipoprotein (LDL) while increased high density lipoprotein (HDL) concentrations (P < 0.05) with a clear response observed in white quails than the brown ones. Besides, CS supplementation increased (P = 0.002) hen day egg production in brown feathered quails, while reducing it in the white-feathered quails compared with the CS-free diet. The increased egg production was not significantly (P > 0.05) correlated with lower content of TG and CHO, while significantly increased the antioxidant content in both quail varieties (P < 0.05). Moreover, CS dietary supplementation significantly enhanced (P = 0.003) the yolk color, especially in brown-feathered quail. In conclusion, CS can be safely supplemented to the Japanese quail diet (1% and 2% for brown-feathered and white-feathered quails respectively) to improve growth performance, and egg quality characteristics

    Xeno-free trans-differentiation of adipose tissue-derived mesenchymal stem cells into glial and neuronal cells.

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    Mesenchymal stem cells (MSCs) are undifferentiated cells that have the ability of self-renewal and trans-differentiation into other cell types. They hold out hope for finding a cure for many diseases. Nevertheless, there are still some obstacles that limit their clinical transplantation. One of these obstacles are the xenogeneic substances added in either proliferation or differentiation media with subsequent immunogenic and infectious transmission problems. In this study, we aimed to replace fetal bovine serum (FBS), the main nutrient source for MSC proliferation with xeno-free blood derivatives. We tested the effect of human activated pure platelet-rich plasma (P-PRP) and advanced platelet-rich fibrin (A-PRF) on the proliferation of human adipose derived-MSCs (AD-MSCs) at different concentrations. For the induction of MSC neural differentiation, we used human cerebrospinal fluid (CSF) at different concentrations in combination with P-PRP to effect xeno-free/species-specific neuronal/glial differentiation and we found that media with 10% CSF and 10% PRP promoted glial differentiation, while media with only 10% PRP induced a neuron-like phenotype

    Interventions for preventing oral mucositis for patients with cancer receiving treatment

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    Interventions for preventing oral mucositis for patients with cancer receiving treatmentTreatment for cancer (including bone marrow transplant) can cause oral mucositis (severe ulcers in the mouth). This painful condition can cause difficulties in eating, drinking and swallowing, and may also be associated with infections which may require the patient to stay longer in hospital. Different strategies are used to try and prevent this condition, and the review of trials found that some of these are effective. Two interventions, cryotherapy (ice chips) and keratinocyte growth factor (palifermin®) showed some benefit in preventing mucositis. Sucralfate is effective in reducing the severity of mucositis, and a further seven interventions, aloe vera, amifostine, intravenous glutamine, granulocyte‐colony stimulating factor (G‐CSF), honey, laser and antibiotic lozenges containing polymixin/tobramycin/amphotericin (PTA) showed weaker evidence of benefit. These were evaluated in patients with different types of cancer, undergoing different types of cancer treatment. Benefits may be restricted to the disease and treatment combinations evaluated

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Diltiazem-tetraiodide bismuthate (III) based PVC membrane for selective determination of diltiazem hydrochloride

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    A new coated-wire electrode based on PVC membrane plasticized with dioctyl phthalate (DOP) and containing the diltiazem-tetraiodido bismuthate (III) ion association coated on a silver wire was constructed and used for potentiometric determination of diltiazem hydrochloride. The electrode performance was characterized and optimized according to the following experimental criteria: membrane composition, soaking time, working pH range, and response time. The interference caused by different species was investigated as well. The best membrane composition was found to be 49.75% of PVC and DOP, 0.5% ion pair. This sensor showed a linear response with a good Nernstian slope of 57.60±1.38 mV/decade over the concentration range5.0×10-5 – 2.50×10-2 M, the detection limit was 2.88×10-5 M, and it was usable within a wide pH range of 2.5–8.0. The electrode showed a fast response time (18 sec), with a relative long lifetime (2.4 months, 2 h a day). The isothermal coefficient (dE°/dT) of the electrode was calculated and found to be 5.36×10-4 V/℃ within 20 – 80℃, which exhibits a good thermal stability. The coted-wire electrode was successfully applied for the potentiometric determination of diltiazem hydrochloride both in pure form and pharmaceutical preparations. The dissolution test of the drug was carried out as well
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