55 research outputs found

    DESIGN IMPROVEMENT OF THE VERTICAL AXIS WIND TURBINE WITH APPLIED FLAPS THROUGH CFD ANALYSIS

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    This research aims to optimise VAWT power generation capabilities through the design alteration of blades by the addition of flaps. The application is aimed to be applied in the United Arab Emirates, specifically at Abu Dhabi University campus in Al Ain to replace a margin of the consumed electrical energy (15%) powered by the typical nonrenewable energy means. To study the effects of design alteration, relevant design parameters on the aerodynamic properties of the wind turbine, a typical standard design with standard dimensions were considered and used as a benchmark for comparison. Two aerodynamic simulation software were adopted, namely ANSYS FLUENT and QBlade, while the designs were drawn through AutoCAD. As per the simulation results, the addition of flaps resulted in an overall increase of 3.11% in power generation. The simulation results were then scaled up using dynamic similarity to obtain a total power consumption of 6 kW for each turbine suggesting that the newly built Al Ain campus would require 43 turbines to cover 15% of the total electricity consumption in a year. The building of a control system for active pitch control was not feasible due to increased complexity

    Stillbirths and quality of care during labour at the low resource referral hospital of Zanzibar: a case-control study

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    Background: To study determinants of stillbirths as indicators of quality of care during labour in an East African low resource referral hospital. Methods: A criterion-based unmatched unblinded case-control study of singleton stillbirths with birthweight ≥2000 g (n = 139), compared to controls with birthweight ≥2000 g and Apgar score ≥7 (n = 249). Results: The overall facility-based stillbirth rate was 59 per 1000 total births, of which 25 % was not reported in the hospital's registers. The majority of singletons had birthweight ≥2000 g (n = 139; 79 %), and foetal heart rate was present on admission in 72 (52 %) of these (intra-hospital stillbirths). Overall, poor quality of care during labour was the prevailing determinant of 71 (99 %) intra-hospital stillbirths, and median time from last foetal heart assessment till diagnosis of foetal death or delivery was 210 min. (interquartile range: 75-315 min.). Of intra-hospital stillbirths, 26 (36 %) received oxytocin augmentation (23 % among controls; odds ratio (OR) 1.86, 95 % confidential interval (CI) 1.06-3.27); 15 (58 %) on doubtful indication where either labour progress was normal or less dangerous interventions could have been effective, e.g. rupture of membranes. Substandard management of prolonged labour frequently led to unnecessary caesarean sections. The caesarean section rate among all stillbirths was 26 % (11 % among controls; OR 2.94, 95 % CI 1.68-5.14), and vacuum extraction was hardly ever done. Of women experiencing stillbirth, 27 (19 %) had severe hypertensive disorders (4 % among controls; OR 5.76, 95 % CI 2.70-12.31), but 18 (67 %) of these did not receive antihypertensives. An additional 33 (24 %) did not have blood pressure recorded during active labour. When compared to controls, stillbirths were characterized by longer admissions during labour. However, substandard care was prevalent in both cases and controls and caused potential risks for the entire population. Notably, women with foetal death on admission were in the biggest danger of neglect. Conclusions: Intrapartum management of women experiencing stillbirth was a simple yet strong indicator of quality of care. Substandard care led to perinatal as well as maternal risks, which furthermore were related to unnecessary complex, time consuming, and costly interventions. Improvement of obstetric care is warranted to end preventable birth-related deaths and disabilities. Trial registration: This is the baseline analysis of the PartoMa trial, which is registered on ClinicalTrials.org (NCT02318420, 4th November 2014)

    Tempol improves optic nerve histopathology and ultrastructures in cisplatin-induced optic neuropathy in rats by targeting oxidative stress—Endoplasmic reticulum stress—Autophagy signaling pathways

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    IntroductionOptic neuropathy is an affection of the optic neurons, which ends with blindness and occurs either primarily due to direct affection of the optic nerve or secondarily as a complication of chronic diseases and/or adverse effects of their therapy. The search for novel therapeutic tools is crucial in addressing the limited therapeutic approaches for optic neuropathy. Therefore, the present study was developed to investigate the possible ameliorative effect of tempol against cisplatin-induced optic neuropathy and its underlying mechanism.MethodsForty-eight adult male albino Wistar rats were divided into four equal groups—control, tempol (TEM), cisplatin (CIS), and tempol and cisplatin combined (TEM+CIS). Optic nerve oxidative stress (MDA, SOD, and GPx), gene expression of endoplasmic reticulum stress (ATF-6, XBP-1, BIP, CHOP, and JNK), autophagy 6 (LC3, Beclin-1, and p62) markers, nerve growth factor-1, immunohistochemical expression of (LC3 and p62), histopathological, and electron microscopic examination were performed.ResultsHistopathological and ultrastructure examination validated that cisplatin caused optic neuropathy by inducing oxidative stress, upregulating ER stress markers, and downregulating autophagy markers, and NGF-1 expression. TEM + CIS showed improvement in optic nerve structure and ultrastructure along with oxidative stress, ER stress mRNA, autophagy (immunohistochemical proteins and mRNA) markers, and nerve growth factor mRNA expression.ConclusionsBased on previous findings, tempol represents a valid aid in cisplatin-induced optic neuropathy by implicating new molecular drug targets (ER stress and autophagy) for optic neuropathy therapy

    Curative and protective potentials of Moringa oleifera leaf decoction on the streptozotocin-induced diabetes mellitus in albino rats

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    The present study was designed to investigate the protective, and curative potentials of Moringa oleifera (MO) leaves powder against streptozotocin (STZ) induced type 1 diabetes mellitus (T1DM) in rats. Fifty adult Wistar male albino rats were randomized and divided into five equal groups: The normal control group, the Moringa group, The diabetic group, the therapeutic group, and the diabetic rats (3 days after STZ injection) were received-MO-for successive 8 weeks and the prophylactic group, the rats were received-MO-for 2 weeks before STZ induced diabetic rats and lasted for 8 weeks. The protective or treated oral administration of 1 ml freshly prepared aqueous leaf decoction of-MO-revealed a significant upregulation of the mRNA expression of PDX-1, Ngn3, VEGF, IGF-1, and GLUT-2. Additionally, it induced a significant downregulation of FBG level compared to that of the diabetic group, a significant reduction in MDA level and a significant elevation in the TAC level. Furthermore, the histopathological observations of pancreas, liver, and kidney tissues affirmed the improvement in treated and prophylactic groups compared to STZ-diabetic groups, and the improvement in the prophylactic group was more distinct than the treated group. MO-aqueous leaf extract can treat and protect against STZ-induced T1DM; via its antioxidant action (increase the TAC and decrease MDA). Thus, it has the potential for utilization as a prophylactic against diabetes

    Understanding Shoulder Surfer Behavior and Attack Patterns Using Virtual Reality

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    In this work, we explore attacker behavior during shoulder surfing. As such behavior is often opportunistic and difficult to observe in real world settings, we leverage the capabilities of virtual reality (VR). We recruited 24 participants and observed their behavior in two virtual waiting scenarios: at a bus stop and in an open office space. In both scenarios, participants shoulder surfed private screens displaying different types of content. From the results we derive an understanding of factors influencing shoulder surfing behavior, reveal common attack patterns, and sketch a behavioral shoulder surfing model. Our work suggests directions for future research on shoulder surfing and can serve as a basis for creating novel approaches to mitigate shoulder surfing

    Scaling up context-tailored clinical guidelines and training to improve childbirth care in urban, low-resource maternity units in Tanzania: A protocol for a stepped-wedged cluster randomized trial with embedded qualitative and economic analyses (The PartoMa Scale-Up Study)

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    While facility births are increasing in many low-resource settings, quality of care often does not follow suit; maternal and perinatal mortality and morbidity remain unacceptably high. Therefore, realistic, context-tailored clinical support is crucially needed to assist birth attendants in resource-constrained realities to provide best possible evidence-based and respectful care. Our pilot study in Zanzibar suggested that co-created clinical practice guidelines (CPGs) and low-dose, high-frequency training (PartoMa intervention) were associated with improved childbirth care and survival. We now aim to modify, implement, and evaluate this multi-faceted intervention in five high-volume, urban maternity units in Dar es Salaam, Tanzania (approximately 60,000 births annually). This PartoMa Scale-up Study will include four main steps: I. Mixed-methods situational analysis exploring factors affecting care; II. Co-created contextual modifications to the pilot CPGs and training, based on step I; III. Implementation and evaluation of the modified intervention; IV. Development of a framework for co-creation of context-specific CPGs and training, of relevance in comparable fields. The implementation and evaluation design is a theory-based, stepped-wedged cluster-randomised trial with embedded qualitative and economic assessments. Women in active labour and their offspring will be followed until discharge to assess provided and experienced care, intra-hospital perinatal deaths, Apgar scores, and caesarean sections that could potentially be avoided. Birth attendants\u27 perceptions, intervention use and possible associated learning will be analysed. Moreover, as further detailed in the accompanying article, a qualitative in-depth investigation will explore behavioural, biomedical, and structural elements that might interact with non-linear and multiplying effects to shape health providers\u27 clinical practices. Finally, the incremental cost-effectiveness of co-creating and implementing the PartoMa intervention is calculated. Such real-world scale-up of context-tailored CPGs and training within an existing health system may enable a comprehensive understanding of how impact is achieved or not, and how it may be translated between contexts and sustained.Trial registration number: NCT04685668

    BM-MSCs alleviate diabetic nephropathy in male rats by regulating ER stress, oxidative stress, inflammation, and apoptotic pathways

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    Introduction: Diabetic nephropathy (DN), a chronic kidney disease, is a major cause of end-stage kidney disease worldwide. Mesenchymal stem cells (MSCs) have become a promising option to mitigate several diabetic complications.Methods: In this study, we evaluated the therapeutic potential of bone marrow-derived mesenchymal stem cells (BM-MSCs) in a rat model of STZ-induced DN. After the confirmation of diabetes, rats were treated with BM-MSCs and sacrificed at week 12 after treatment.Results: Our results showed that STZ-induced DN rats had extensive histopathological changes, significant upregulation in mRNA expression of renal apoptotic markers, ER stress markers, inflammatory markers, fibronectin, and intermediate filament proteins, and reduction of positive immunostaining of PCNA and elevated P53 in kidney tissue compared to the control group. BM-MSC therapy significantly improved renal histopathological changes, reduced renal apoptosis, ER stress, inflammation, and intermediate filament proteins, as well as increased positive immunostaining of PCNA and reduced P53 in renal tissue compared to the STZ-induced DN group.Conclusion: In conclusion, our study indicates that BM-MSCs may have therapeutic potential for the treatment of DN and provide important insights into their potential use as a novel therapeutic approach for DN

    Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

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    Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

    Silymarin-loaded chitosan nanoparticles alleviate dyslipidemia, oxidative stress, metabolic disturbance and histopathological injury associated with high fat diet-induced non-alcoholic fatty liver disease in rats

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    With an increasing incidence of obesity and metabolic syndrome epidemic, nonalcoholic fatty liver disease (NAFLD) continues to be one of the most prevalent liver illnesses worldwide. One of recommended treatment in NAFLD is silymarin. Howerver, the problem is that silymarin has weak water solubility and limited bioavilability. Therefore, prepration of silymarin in nano-formulation would enhance silymarin's therapeutic effects and bioavailability. This study was designed to evaluate the biochemical and molecular effects of silymarin-loaded chitosan nanoparticles (SILCSNPs) in NAFLD treatment in rats. Fifty rats were divided into five groups include: Group 1: Control group, group 2: HFD-induced NAFLD, group 3: HFD-induced NAFLD that orally received nano-chitosan, group 4: HFD-induced NAFLD that orally received nano-silymarin and group 5: HFD-induced NAFLD that orally received silymarin-loaded chitosan nanoparticles (SILCSNPs). The dose of each treatment was 40 mg/kg/day for 60 days. Lipid parameters (triglycerides, total cholesterol), ALT, AST, hepatic (catalase, SOD and MDA) and mRNA expression of lipogenesis-related genes including ACC (acetyl-CoA carboxylase) and FASN (fatty acid synthase) as well as fatty acids catabolism-related genes including CPT-1 (carnitine palmitoyl-transferase I), PPAR-α (peroxisome proliferator-activated receptor alpha) were measured. Histopathological examination of liver was also conducted. A significant elevation in HDL, catalase, SOD, CPT-1, PPAR-α levels as well as substantial reduction in triglycerides, cholesterol, ALT, AST, MDA, ACC and FASN levels were detected in treated groups in compared to the HFD-induced NAFLD group. Histopathological examination of the liver showed histological amelioration in hepatic tissue in treated groups in compared to the HFD-induced NAFLD group. SILCSNPs revealed a significant potential effect against NAFLD metabolic disturbance and considered an advanced trend in NAFLD treatment

    Cutting bone with drills, burs, lasers and piezotomes: A comprehensive systematic review and recommendations for the clinician

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    Background: New tools for bone-cutting were introduced to oral and maxillofacial surgery in the last decade, such as lasers and piezotomes.Purpose: to evaluate most recent evidence, when surgical procedures performed with drills or burs are compared with laser- and/or piezotome-surgical procedures in experimental and clinical studies and to assess possible advantages of their use in daily practice.Methods: a systematic search of various medical databases with specific keywords was performed, excluding studies published before 2006 for their possible invalidity by technological progress. Systematic reviews were assigned to Group 1, experimental studies ex vivo to Group 2, in vivo to Group3 and clinical studies to Group 4. All studies in each of the groups 2 – 4 were appraised regarding their evidence, starting with a value of 0 for no evidence of advantages of lasers and/or piezotomes compared to rotary instruments, 1 for moderate evidence with verifi ed clinical impact and 2 for strong evidence and signifi cant clinical impact and statistically processed for their Evidence Value (EV) in each group and their Overall mean Evidence Value (OmEV).Results: 129 studies were fi nally included for evaluation. Two systematic reviews concluded lack of evidence for lasers to be advantageous over burs/drills. Nine reviews for piezotomes reveal strong evidence piezotome-surgery to signifi cantly reduce morbidity and to enhance soft-tissue preservation. Comparative experimental and clinical studies of burs/drills vs lasers revealed a low EV in Group 2 (EV:0,8), Group 3 (EV:0,5) and Group 4 (EV:0,5) with an OmEV of 0,6. Comparative studies burs/drills vs piezotomes resulted in a signifi cant EV in all groups (Group 2: 1,4, Group 3: 1,3, Group 4: 1,59) with an OmEV of 1,4.Conclusions: the results suggest too little evidence to establish lasers as an alternative to rotary instruments. Piezotomes seem to defi ne a possible new gold-standard in bone cutting due to their improved bone-healing, almost bone-lossless and precise osteotomy design, precise depth-control, softtissue protection as well as reduced intrasurgical and post-surgical morbidity.</p
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