Role of vanadium ions substitution on spinel MnCo2O4 towards enhanced electrocatalytic activity for hydrogen generation

This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.Improving efficient electrocatalysts (ECs) for hydrogen generation through water splitting is of significant interest in tackling the upcoming energy crisis. Sustainable hydrogen generation is the primary prerequisite to realizing the future hydrogen economy. This work examines the electrocatalytic activity of hydrothermally prepared vanadium doped MnCo spinel oxide microspheres (MC), MnVxCo2−xO4 (Vx-MnCo MC, where x ≤ 0.4) in the HER (hydrogen evolution reaction) process. Magnetization measurements demonstrated a paramagnetic (at high temperatures) to a ferrimagnetic (at low temperatures) transition below the Curie temperature (Tc) in all the samples. The magnetization is found to intensify with the rising vanadium content of MCs. The optimized catalyst Vx-MnCo MCs (x = 0.3) outperformed other prepared ECs with a Tafel slope of 84 mV/dec, a low onset potential of 78.9 mV, and a low overpotential of 85.9 mV at a current density of 10 mA/cm2, respectively. The significantly improved HER performance of hydrothermally synthesized Vx-MnCo MCs (x = 0.3) is principally attributable to many exposed active sites, accelerated electron transport at the EC/electrolyte interface, and remarkable electron spectroscopy for chemical analysis (ECSA) value was found ~ 11.4 cm2. Moreover, the Vx-MnCo MCs (x = 0.3) electrode exhibited outstanding electrocatalytic stability after exposure to 1000 cyclic voltametric cycles and 36 h of chronoamperometric testing. Our results suggest a feasible route for developing earth-abundant transition metal oxide-based EC as a superior electrode for future water electrolysis applications.British CouncilKACARE Fellowshi

Co-sensitization effect of N719 dye with Cu doped CdS colloidal nanoparticles for dye sensitized solar cells

This is the final version. Available on open access from Elsevier via the DOI in this recordData availability: Data will be made available on request.Dye-sensitized solar cell’s (DSSC) performances are enhanced by engineering the materials at the interface of various device components owing to easy and inexpensive fabrication steps. Ru (II) polypyridyl-based synthetic dyes are the most widely used photosensitizers for DSSCs due to their superior molar extinction coefficient and facile interaction with metal oxide electrodes. However, these dyes are mostly expensive, and as a result, natural dyes and metal-free organic dyes have become an alternative way for sensitization to reduce the significant drawbacks of synthetic dyes. In this study, minimizing the usage of the N719 dye can be performed through an alternative method for better light-harvesting through supreme optical interfacial interaction with colloidal Cu-doped CdS as a co-sensitizer in a facile approach. This co-sensitization signifies the colloidal CdS (donor), which can corroborate the energy transfer mechanism with the N719 dye (acceptor). The introduction of Cu causes extreme tuning of broad absorption to near-infrared for CdS, enhancing the solar light harvesting entrapment followed by extensive optical interaction with N719 dye. This accelerates the activity of the sensitizers for light absorption enhancement and expects a better performance of DSSC compared to traditional sensitization. A massive improvement in photocurrent density (∼42 %) was observed without sacrificing other photovoltaic parameters, as observed for TiO2-based photoanodes. The sensitizer’s interfacial optical energy transfer process, unless excited electron recombination, may indirectly be used as an excitation source of the acceptor and minimizes the recombination energy loss.Engineering and Physical Sciences Research Council (EPSRC)British Counci

Microbial community composition of deep-sea corals from the Red Sea provides insight into functional adaption to a unique environment

Microbes associated with deep-sea corals remain poorly studied. The lack of symbiotic algae suggests that associated microbes may play a fundamental role in maintaining a viable coral host via acquisition and recycling of nutrients. Here we employed 16 S rRNA gene sequencing to study bacterial communities of three deep-sea scleractinian corals from the Red Sea, Dendrophyllia sp., Eguchipsammia fistula, and Rhizotrochus typus. We found diverse, species-specific microbiomes, distinct from the surrounding seawater. Microbiomes were comprised of few abundant bacteria, which constituted the majority of sequences (up to 58% depending on the coral species). In addition, we found a high diversity of rare bacteria (taxa at 90% of all bacteria). Interestingly, we identified anaerobic bacteria, potentially providing metabolic functions at low oxygen conditions, as well as bacteria harboring the potential to degrade crude oil components. Considering the presence of oil and gas fields in the Red Sea, these bacteria may unlock this carbon source for the coral host. In conclusion, the prevailing environmental conditions of the deep Red Sea (>20 °C, <2 mg oxygen L−1) may require distinct functional adaptations, and our data suggest that bacterial communities may contribute to coral functioning in this challenging environment.This work was supported from baseline funds to CRV and under the Center Competitive Funding (CCF) Program FCC/1/1973-18-01 by the King Abdullah University of Science and Technology (KAUST)

Effect of Blend of Essential Oils on Growth Performance, Carcass Characteristics, Meat Quality, Intestinal Morphology, Serum Biochemistry, and Immune Response of Broiler Chickens

ABSTRACT The purpose of this study was to assess the impact of a blend of essential oils from eucalyptus, citrus, bromohexene HCl, thymole and camphor on the growth performance, carcass characteristics, meat quality, intestinal morphology, serum biochemistry, and immune response of broiler chickens. A total of 240 day-old chicks were divided into four groups, each with six replicates containing ten birds. The experiment was conducted under a completely randomized design (CRD). Different concentrations of the oil blend (0mL/kg, 0.15mL/kg, 0.30mL/kg and 0.45mL/kg) were added to the diet. The findings showed that, in comparison to the other groups, the birds that were given a blend of essential oils at concentrations of 0.30 and 0.45 mL/kg showed improved weight gain, feed efficiency, carcass yield, villus height, crypt depth, and greater immune response against Newcastle disease vaccination (p<0.05). Nonetheless, there was no statistically significant difference in the yields of the breast and thighs, feed consumption, mortality, weights of the liver, wing, heart, and gizzard, or abdominal fat between the treatments. The addition of a blend of essential oils at the doses of 0.30 and 0.45 mL/kg significantly lowered the pH of the meat in comparison to the other groups (p<0.05). All blood biochemical markers, including total serum protein, albumin, globulin, glucose, cholesterol, triglyceride, and uric acid, revealed no variations between the treatments. In conclusion, adding 0.30mL/kg of a blend of essential oils to broiler diets may be the optimum level to improve overall performance without adversely affecting the blood biochemical profile

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030