76 research outputs found

    Tailoring Cu Electrodes for Enhanced CO 2 Electroreduction through Plasma Electrolysis in Non‐Conventional Phosphorus‐Oxoanion‐Based Electrolytes

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    This study presents a green, ultra-fast, and facile technique for the fabrication of micro/nano-structured and porous Cu electrodes through in-liquid plasma electrolysis using phosphorous-oxoanion-based electrolytes. Besides the preferential surface faceting, the Cu electrodes exhibit unique surface structures, including octahedral nanocrystals besides nanoporous and microporous structures, depending on the employed electrolyte. The incorporation of P-atoms into the Cu surfaces is observed. The modified Cu electrodes display increased roughness, leading to higher current densities for CO2 electroreduction reaction. The selectivity of the modified Cu electrodes towards C2 products is highest for the Cu electrodes treated in Na2HPO3 and Na3PO4 electrolytes, whereas those treated in Na2H2PO2 produce the most H2. The Cu electrode treated in Na3PO4 produces ethylene (23 %) at −1.1 V vs. RHE, and a comparable amount of acetaldehyde (15 %) that is typically observed for Cu(110) single crystals. The enhanced selectivity is attributed to several factors, including the surface morphology, the incorporation of phosphorus into the Cu structure, and the formation of Cu(110) facets. Our results not only advance our understanding of the influence of the electrolyte\u27s nature on the plasma electrolysis of Cu electrodes, but also underscores the potential of in-liquid plasma treatment for developing efficient Cu electrocatalysts for sustainable CO2 conversion

    Pomegranate peel as a natural antioxidant boosts bucks' fertility under Egyptian summer conditions

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    [EN] Exposure of male rabbits to heat stress during summer adversely affects their fertility, leading to major production losses. A total of 16 male rabbits were randomly divided into 4 experimental groups exposed to temperatures ranging from a high of 30.3 to a low of 27.3 °C. Animals from first to fourth groups were fed diets containing 0, 1.5, 3.0, or 4.5% pomegranate peel (PP) to evaluate the ability of PP feeding to enhance bucks¿ reproductive status. Pomegranate peel treatments significantly increased ejaculate volume by 19, 18 and 12%, increased seminal plasma fructose by 7, 18, and 24%, improved sperm motility by 28, 34 and 49%, increased sperm total output by 37, 69 and 102% and reduced dead sperm by 24, 32 and 64% with diets containing 1.5, 3.0 and 4.5% of PP compared to the heat stressed control animals. Seminal plasma total lipids, cholesterol and triglycerides increased while alkaline phosphatase decreased with PP treatments. Seminal plasma total antioxidant capacity increased to reach 126, 143 and 191% with diets containing 1.5, 3.0 and 4.5% of PP, while lipid peroxide (malondialdehyde) levels decreased significantly to reach around 54% of the heat stressed bucks¿ value with the three PP dietary doses used. It was concluded that supplementations of PP in the diet of bucks during summer season in Egypt can improve their semen characteristics, probably due to their antioxidant actions.Zeweil, HS.; Elnagar, S.; Zahran, SM.; Ahmed, MH.; El-gindy, Y. (2013). Pomegranate peel as a natural antioxidant boosts bucks' fertility under Egyptian summer conditions. World Rabbit Science. 21(1):33-39. doi:10.4995/wrs.2013.1209.SWORD333921

    Water-soluble ionic carbon nitride as unconventional stabilizer for highly catalytically active ultrafine gold nanoparticles

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    Ultrafine metal nanoparticles (NPs) hold promise for applications in many fields, including catalysis. However, ultrasmall NPs are typically prone to aggregation, which often leads to performance losses, such as severe deactivation in catalysis. Conventional stabilization strategies (e.g., immobilization, embedding, or surface modification by capping agents) are typically only partly effective and often lead to loss of catalytic activity. Herein, a novel type of stabilizers based on water-soluble ionic (K+^+ and Na+^+ containing) polymeric carbon nitride (i.e., K,Na-poly(heptazine imide) = K,Na-PHI) is reported that enables effective stabilization of highly catalytically active ultrafine (size of ∌2–3 nm) gold NPs. Experimental and theoretical comparative studies using different structural units of K,Na-PHI (i.e., cyanurate, melonate, cyamelurate) indicate that the presence of functionalized heptazine moieties is crucial for the synthesis and stabilization of small Au NPs. The K,Na-PHI-stabilized Au NPs exhibit remarkable dispersibility and outstanding stability even in solutions of high ionic strength, which is ascribed to more effective charge delocalization in the large heptazine units, resulting in more effective electrostatic stabilization of Au NPs. The outstanding catalytic performance of Au NPs stabilized by K,Na-PHI is demonstrated using the selective reduction of 4-nitrophenol to 4-aminophenol by NaBH4_4 as a model reaction, in which they outperform even the benchmark “naked” Au NPs electrostatically stabilized by excess NaBH4_4. This work thus establishes ionic carbon nitrides (PHI) as alternative capping agents enabling effective stabilization without compromising surface catalysis, and opens up a route for further developments in utilizing PHI-based stabilizers for the synthesis of high-performance nanocatalysts

    Development of new thiazolidine-2,4-dione hybrids as aldose reductase inhibitors endowed with antihyperglycaemic activity: design, synthesis, biological investigations, and in silico insights

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    This research study describes the development of new small molecules based on 2,4-thiazolidinedione (2,4-TZD) and their aldose reductase (AR) inhibitory activities. The synthesis of 17 new derivatives of 2,4-TZDs hybrids was feasible by incorporating two known bioactive scaffolds, benzothiazole heterocycle, and nitro phenacyl moiety. The most active hybrid (8b) was found to inhibit AR in a non-competitive manner (0.16 ”M), as confirmed by kinetic studies and molecular docking simulations. Furthermore, the in vivo experiments demonstrated that compound 8b had a significant hypoglycaemic effect in mice with hyperglycaemia induced by streptozotocin. Fifty milligrams per kilogram dose of 8b produced a marked decrease in blood glucose concentration, and a lower dose of 5 mg/kg demonstrated a noticeable antihyperglycaemic effect. These outcomes suggested that compound 8b may be used as a promising therapeutic agent for the treatment of diabetic complications

    In‐Liquid Plasma for Surface Engineering of Cu Electrodes with Incorporated SiO2 Nanoparticles: From Micro to Nano

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    A robust and efficient route to modify the chemical and physical properties of polycrystalline copper (Cu) wires via versatile plasma electrolysis is presented. Silica (SiO2) nanoparticles (11 nm) are introduced during the electrolysis to tailor the surface structure of the Cu electrode. The influence of these SiO2 nanoparticles on the structure of the Cu electrodes during plasma electrolysis over a wide array of applied voltages and processing time is investigated systematically. Homogeneously distributed 3D coral‐like microstructures are observed by scanning electron microscopy on the Cu surface after the in‐liquid plasma treatment. These 3D microstructures grow with increasing plasma processing time. Interestingly, the microstructured copper electrode is composed of CuO as a thin outer layer and a significant amount of inner Cu2O. Furthermore, the oxide film thickness (between 1 and 70 ”m), the surface morphology, and the chemical composition can be tuned by controlling the plasma parameters. Remarkably, the fabricated microstructures can be transformed to nanospheres assembled in coral‐like microstructures by a simple electrochemical treatment.DFG, 327886311, SFB 1316: Transiente AtmosphĂ€rendruckplasmen - vom Plasma zu FlĂŒssigkeiten zu FestkörpernDFG, 390874152, EXC 2154: POLiS - Post Lithium Storage Cluster of Excellenc

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Global economic burden of unmet surgical need for appendicitis

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    Background: There is a substantial gap in provision of adequate surgical care in many low-and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods: Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results: Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US 92492millionusingapproach1and92 492 million using approach 1 and 73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was 95004millionusingapproach1and95 004 million using approach 1 and 75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion: For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

    Postoperative outcomes in oesophagectomy with trainee involvement

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    BACKGROUND: The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting. METHODS: Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups. RESULTS: Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005). CONCLUSION: Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
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