40 research outputs found
Organic Amino Acids Chelates; Preparation, Spectroscopic Characterization and Applications as Foliar Fertilizers
Cu(II) complexes of amino acid hydrolyzate soya protein isolate have been prepared. In order to study the mode of coordination in the above chelates and their effect as foliar fertilizer, Mn(II), Co(II), Nil(II), Cu(II), Zn(II) and Cd(II) complexes of  L-mino acids have been prepared and characterized by elemental and spectral analyses,( IR, UV-VIS, mass spectra and ESR), electrical conductance, magnetic moments and thermal analyses (DTA and TGA). ESR spectra of copper (II) complexes show isotropic and anisotropic types d(x2-y2) with covalent bond character. The amino acids chelates were evaluated as foliar fertilizer by treating plants with micronutrient, amino acid solutions and varying concentrations of micronutrient amino acids chelats. It was found that spraying plant with 2.5% micronutrient amino acids chelats gives the best results regarding: plant height, stem diameter, leaves area, number of flowers, number of branches per plants and total yield per plant
Cooling Strategies for Heated Cylinders Using Pulsating Airflow with Different Waveforms
Pulsate flow is an effective technique applied for cooling several engineering systems depending on their pulsate frequency. One very sound external flow pulsation application is heat transfer over heated bodies. In present work, an experimental design and numerical model of controlled pulsating flow according to generated pulsating frequency and wave shape around a heated cylinder were performed. The effects of pulsating frequency, amplitude, and mean velocity on the fluid flow and heat transfer characteristics over a heated cylinder were studied. The wave frequency varied from 2 to 12 Hz, and the amplitude varied from 0.2 to 0.8 m/s. Moreover, different waveforms were investigated to determine their effect on wall cooling. For constant wave frequency and amplitude, the most efficient wave in cooling was the sawtooth wave, with the average wall temperature after 30 s was 1.6 °C cooler than that of the forced convection case, followed by the triangular wave at 1.2 °C less. The heat transfer rate and the flow field were drastically influenced by the variations of these parameters. Optimization was conducted for each wave type to find the optimum wave frequency and amplitude. The optimizing showed that, the most efficient wave was the sawtooth with 12°C temperature reduction compared with that of the forced convection case, followed by the triangular. Furthermore, regression analysis was conducted to estimate the relationships between these variables and surface temperature. It was found that the wave amplitude had a greater role in cooling than that of the frequency
Vertical vibrations effect on forced convection heat transfer from a longitudinal finned tube
Thermal systems more efficient by emanating from industrial applications and space program galvanized interest in ways by increasing heat transfer is the system. The main aim of this paper is to investigate experimentally the effects of the vertical vibration and force convection on the average Nusselt number in a longitudinal finned tube. The finned tube was located inclined or horizontally in different angles of 0°, 30° and 45°. The effect of the excitation frequency covers below 16 Hz with various heat fluxes ranged from 500-1500 W/m2. It was noticed that the good agreement between the experimental measurement and the previous experimental studies with deviation of 5%. The results showed that average Nusselt number values at angle 45° from longitudinal finned tube were higher by up to 14%, 16% compared with the angles 30°, and 0°, respectively. Furthermore, it can be summarized that the vertical vibration significantly affects to the average Nusselt number from longitudinal finned tube cylinder and the influence on the heat transfer coefficient for this system should be considered
Mortality and pulmonary complications in patients undergoing surgery with perioperative sars-cov-2 infection: An international cohort study
Background The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (740%) had emergency surgery and 280 (248%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (261%) patients. 30-day mortality was 238% (268 of 1128). Pulmonary complications occurred in 577 (512%) of 1128 patients; 30-day mortality in these patients was 380% (219 of 577), accounting for 817% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 175 [95% CI 128-240], p<00001), age 70 years or older versus younger than 70 years (230 [165-322], p<00001), American Society of Anesthesiologists grades 3-5 versus grades 1-2 (235 [157-353], p<00001), malignant versus benign or obstetric diagnosis (155 [101-239], p=0046), emergency versus elective surgery (167 [106-263], p=0026), and major versus minor surgery (152 [101-231], p=0047). Interpretation Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research
Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study
Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
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
S128 FUNCTIONAL AND ANATOMICAL CHARACTERIZATION OF CORTICOTROPIN-RELEASING FACTOR RECEPTOR SUBTYPES OF RAT SPINAL CORD INVOLVED IN THE MODULATION OF INFLAMMATORY PAIN
Hybrid nanofluid to enhance heat transfer under turbulent flow in a flat tube
The heat transfer enhancement by utilizing hybrid nanofluid is a new class of heat transfer enhancement. In this paper, CFD model with commercial software adopting the finite volume method and SIMPLE algorithm has been conducted. Mixture of Aluminum Nitride (AlN) and alumina (Al2O3) nanoparticles into water as a base fluid is considered as a new concept of hybrid nanofluid for enhancing heat transfer. It was performed the simulation procedures with the volume fraction (1, 2, 3 and 4%) and Reynolds number are changing from 5000 to 17000. The heat flux applied along the elliptical tube is 7000 w/m2 and the nanoparticles size diameter is fixed at 35 nm. The validation of computational results has been performed with experimental data available in the literature. The results indicated that the hybrid nanoparticles of AlN - Al2O3 suspended in water as a base fluid tends to enhance heat transfer significantly. Keywords: Hybrid, Nanofluid, Performance, Turbulent, CFD, ANSY
Mosquito Fauna (Diptera, Culicidae) In Tarhuna Region, Libya
Khalefa, A. S., Ghana, S., Rashid, N. M., Shaibi, T. (2022): Mosquito Fauna (Diptera, Culicidae) In Tarhuna Region, Libya. Zoodiversity 56 (2): 111-116, DOI: 10.15407/zoo2022.02.111, URL: http://dx.doi.org/10.15407/zoo2022.02.11