Synthesis of ErBa2Cu3O7-δ superconducting ceramic material via co precipitation and conventional solid state routes

High temperature superconductors (HTSC) of microcrystalline ceramic material ErBa2Cu3O7-δ (ErBCO) have been successfully synthesized via chemical co-precipitation (COP) using metal acetate precursors, and physical mixtures of oxides and carbonates, by conventional solid state route (SSR). The COP sample requires 27 hours for the heat treatment while the SSR sample needs 72 hours. We compare the superconducting properties of ErBCO produced from both methods. Resistivity versus temperature measurements (R-T) showed that all samples exhibit very good metallic behaviour. The transition temperature, TC(R=0) for the COP samples were was found to be at 91.4 K while it occurs at 90.9 K for the SSR sample sintered at 920°C. X-ray diffraction (XRD) data showed a single phase of an orthorhombic structure for all the samples. Scanning electron micrographs (SEM) showed grains of sizes ≤ 40μm were randomly distributed in all the highly compacted samples. However, the sample prepared via COP exhibited smaller pores in comparison to those in the SSR sample. COP method simplifies the preparation, and gives good quality sample with shorter time of preparation as compared to the quality of sample prepared by conventional solid state route

Colonizer to Drug Resistant isolate, What is Happening to our Staphylococcus Aureus?

Objective: To evaluate resistant trend of multiple antimicrobial agents against Staphylococcus aureus isolates along with its prevalence.  Material and Methods: This prospective descriptive study was carried out in the department of microbiology Allama Iqbal Medical College Lahore from 1st January 2015 to 25 may 2016. Simple random technique was used, and 4570 clinical samples (Pus, blood, pleural fluid, tracheal aspirate, urine, sputum, HVS) were received from ICU, Surgical Unit, Medical Unit and OPD for culture sensitivity testing, antimicrobial resistant trend was tested according to CLSI guidelines  Results: Maximum isolates were recovered from surgical unit 31.9%, sample-wise maximum isolates were recovered from pus samples 26.8%. age group and genderbased distribution showed among male’s high isolation rate was observed in 21-40 years while in females 41-60-year age group. Every isolate was (100%) susceptible to linezolid, vancomycin and teicoplanin, cotrimoxazole also showed very low rate of drug resistance only 8.3%, while penicillin Doxycycline, Ciprofloxacin, Erythromycin showed 95.9%,69.8%55.4% and 48.2% drug resistance respectively, 43-45% drugresistant rate observed in case of Co-amoxiclave, Methicillin, Gentamicin, Fusidic Acid, Amikacin, and Clindamycin  Conclusion: Linezolid, Vancomycin, and Teicoplanin are best therapeutic Choices against Staphylococcus aureus associated infections

Miniaturized and flexible FSS-based EM shields for conformal applications

This article reports on very efficient and highly miniaturized wideband polygon-shaped frequency selective surface (PFSS) shields for the planar and conformal applications in the X-band. These shields have been analyzed for both lossy as well as for low-loss substrates. The conformal configurations of PFSS are particularly investigated for inward, outward, and double-curved profiles useful for a variety of applications. The conformal designs have been tested for two different radii of curvatures. The models have been simulated using a hybrid simulation approach for electrically large geometries. The equivalent circuit model as well as the analytical model are determined. The proposed PFSS designs offer stable angular response up to 60° for planar and all conformal geometries on both lossy and low-loss prototypes. Shielding effectiveness of at least 55 dB and 48 dB has been measured for flat/nonconformal and conformal configurations, respectively

Abrasive stripping voltammetric (AbrSV) studies of ErBa2Cu3O7-δ superconductor synthesised via co-precipitation and solid state methods

The electrochemical analysis of ErBa2Cu3O7-δ (ErBCO) superconductor ceramic materials, adhered abrasively at a glassy carbon electrode surface placed in an aqueous media has been investigated by abrasive stripping voltammetry, AbrSV technique. ErBCO samples were prepared via co-precipitation (COP) and solid state (SS) method. Powder x-ray diffraction (XRD) patterns showed both samples to be single-phased 123 of an orthorhombic structure. Details studies on the reduction-oxidation of ErBCO involved the variation of scan rate, temperature and pH of electrolyte as well as chronoamperometry (CA) and chronocoulometry (CC). The voltammogram obtained for ErBCO prepared in both methods showed four major peaks attributed to first and second redox couples. The peaks are due to the redox reaction of Cu(NH3)42+ complex. The peak current is highly dependent upon the formation of the Cu(NH3)42+ complex which shows that the copper planes in the superconductor played major role in producing the peaks observed in the voltammograms. The voltammetric response of the ErBCO was found to depend greatly on the scan rate, pH and temperature. From CA and CC studies, the amount of charge, Q that was presence on the electrode surface is 4.7 μC/cm2 and 5.4 μC/cm2 and diffusion coefficient, D is 3.4 x 10-6 cm2/s and 4.0 x 10-6 cm2/s for solid state and co-precipitation method respectively

Spatial distribution of carbon dynamics and nutrient enrichment capacity in different layers and tree tissues of Castanopsis eyeri natural forest ecosystem

Forest ecosystem carbon (C) storage primarily includes vegetation layers C storage, litter C storage, and soil C storage. The precise assessment of forest ecosystem C storage is a major concern that has drawn widespread attention in global climate change worldwide. This study explored the C storage of different layers of the forest ecosystem and the nutrient enrichment capacity of the vegetation layer to the soil in the Castanopsis eyeri natural forest ecosystem (CEF) present in the northeastern Hunan province, central China. The direct field measurements were used for the estimations. Results illustrate that trunk biomass distribution was 48.42% and 62.32% in younger and over-mature trees, respectively. The combined biomass of the understory shrub, herb, and litter layers was 10.46 t·hm−2, accounting for only 2.72% of the total forest biomass. On average, C content increased with the tree age increment. The C content of tree, shrub, and herb layers was 45.68%, 43.08%, and 35.76%, respectively. Litter C content was higher in the undecomposed litter (44.07 %). Soil C content continually decreased as the soil depth increased, and almost half of soil C was stored in the upper soil layer. Total C stored in CEF was 329.70 t·hm−2 and it follows the order: tree layer > soil layer > litter layer > shrub layer > herb layer, with C storage distribution of 51.07%, 47.80%, 0.78%, 0.25%, and 0.10%, respectively. Macronutrient enrichment capacity from vegetation layers to soil was highest in the herb layer and lowest in the tree layer, whereas no consistent patterns were observed for trace elements. This study will help understand the production mechanism and ecological process of the C. eyeri natural forest ecosystem and provide the basics for future research on climate mitigation, nutrient cycling, and energy exchange in developing and utilizing sub-tropical vegetationThis research was financially supported by research funding from Central South University of Forestry and Technology and the Hunan province finance department (No.70702-45200003

Monitoring the Impact of Rapid Urbanization on Land Surface Temperature and Assessment of Surface Urban Heat Island Using Landsat in Megacity (Lahore) of Pakistan

The present study focused on rapid urbanization due to the change in the existing landforms which has caused substantial adverse impacts on Urban Thermal Environment. In the present study, we have acquired the Landsat data (TM and OLI) for the years 1990, 2000, 2010, and 2020 to observe the land use changes (vegetation cover, built up land, barren land, and water) in Lahore using the supervised image classification method. Later, the impact of urbanization has been examined with Land Surface Temperature (LST) and eventually the Surface Urban Heat Island (SUHI) has been calculated. Accuracy of the classified images revealed an overall accuracy (Kappa co-efficient) of 95.3% (0.929%), 92.05% (0.870%), 89.7% (0.891%), and 85.8% (0.915%) for the years 1990, 2000, 2010, and 2020, respectively. It was found that vegetation cover decreased from 60.5% in 1990 to 47.7% in 2020 at the cost of urbanization. The overall built-up land increased by 23.52% from 1990 to 2020. Urbanization has influenced the LST, and it was examined that maximum LST consistently increased with increase in built-up land. The difference between urban and rural buffer reveals that SUHI has also been increasing over the years. SUHI has been raised from 1.72 C in 1990 to 2.41 C in 2020, and about 0.69 C relative change has been observed. It has also been observed that the Normalized Difference Vegetation Index (NDVI) and LST have an inverse relationship. The research outcomes of this study are useful for urban climatologists, urban planners, architects, and policymakers to devise climate resilient policies, structure, and decisions to balance the urban green spaces for a healthy urban environment

Phase formation of REBa2Cu3O7−δ (RE: Y0.5Gd0.5, Y0.5Nd0.5, Nd0.5Gd0.5) superconductors from nanopowders synthesised via co-precipitation

Phase formation of REBa2Cu3O7−δ (RE: Y0.5Gd0.5, Y0.5Nd0.5, Nd0.5Gd0.5) superconductors synthesised via co-precipitation (COP) method were investigated by thermogravimetric analysis (TGA), differential thermal analysis (DTA) and X-ray diffraction (XRD) analysis. All samples showed identical thermal decomposition behaviour from the thermogram in which 5 major weight losses were observed. However, XRD of the samples at different heat treatment temperatures showed different diffraction patterns indicating different thermolytic processes. Meanwhile, transmission electron microscopy and surface area analysis revealed that the powders obtained from COP have particle sizes ranging from 7 to 12 nm with relatively large surface area. Molar ratios of prepared samples obtained were near to the theoretical values as confirmed by elemental analyses using X-ray fluorescence (XRF). The TC(R=0) for sintered YGd, YNd and NdGd were 87 K, 86 K and 90 K, respectively. Surface morphological study via scanning electron microscope showed the structures of samples were dense and non porous

Comparative Analysis of Production Processes and Quality Parameters of Two Different Semi-Combed Yarns

Semi-combed yarn represents a type of ring-spun yarn produced by modifying the typical carded and combed yarn manufacturing process. Carded yarn is inferior in quality, while combed yarns are not cost efficient. The semi-combed yarn has therefore emerged as an alternative to fully combed yarn to facilitate a reasonable quality-cost compromise. This paper reports two manufacturing techniques and associated features of the cotton ring-spun semi-combed yarn of the same count. One process involves sliver mixing in draw frame, and the other by reducing the noil extraction percentage in comber. The aim of this study is to run a comparative analysis of both the end products against themselves and their carded and combed counterparts to establish their acceptance in the industrial scale. Important quality parameters such as unevenness (U%), coefficient of variation (CVm%), thick place(+50%)/km, thin place(−50%)/km, neps(+200%)/km, hairiness (H), strength, elongation, CSP, and cost have been evaluated, analyzed, and compared among these products. In several cases, the quality of semi-combed yarn was comparable to fully combed yarns and better than carded yarns. This offers a cost-effective and sustainable alternative to combed yarn. Comparison shows that the noil extraction process offers less hairiness, and more sustainability and involves no extra operation to develop the yarn

Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

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

Summary 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 middleincome 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 lowincome 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 lowincome, 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