9 research outputs found

    Optimisation of flow resistance and turbulent mixing over bed forms

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    Previous work on the interplay between turbulent mixing and flow resistance for flows over periodic rib roughness elements is extended to consider the flow over idealized shapes representative of naturally occurring sedimentary bed forms. The primary motivation is to understand how bed form roughness affects the carrying capacity of sediment-bearing flows in environmental fluid dynamics applications, and in engineering applications involving the transport of particulate matter in pipelines. For all bed form shapes considered, it is found that flow resistance and turbulent mixing are strongly correlated, with maximum resistance coinciding with maximum mixing, as was previously found for the special case of rectangular roughness elements. Furthermore, it is found that the relation between flow resistance to eddy viscosity collapses to a single monotonically increasing linear function for all bed form shapes considered, indicating that the mixing characteristics of the flows are independent of the detailed morphology of individual roughness elements

    Individual-level predictors of inpatient childhood burn injuries: a case–control study

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    Abstract Background Burn injuries are considered one of the most preventable public health issue among children; however, are a cause of significant morbidity and mortality in Iran. The aim of this study was to assess individual-level predictors of severe burn injuries among children leading to hospitalization, in East Azerbaijan Province, in North-West of Iran. Methods The study was conducted through a hospital based case–control design involving 281 burn victims and 273 hospital-based controls who were frequency matched on age, gender and urbanity. Both bivariate and multivariate methods were used to analyze the data. Results Mean age of the participants was 40.5 months (95 % CI: 37–44) with the majority of burns occurring at ages between 2 months-13.9 years. It was demonstrated that with increase in the caregiver’s age there was a decrease in the odds of burn injuries (OR = 0.94, 95 % CI: 0.92-0.97). According to the multivariate logistic regression there were independent factors associated with burn injuries including childhood ADHD (OR = 2.82, 95 % CI: 1.68 - 4.76), child’s age (OR = 0.73, 95%CI: 0.67 - 0.80), flammability of clothing (OR = 1.60, 95 % CI: 1.12 - 2.28), daily length of watching television (OR = 1.31, 95 % CI: 1.06 - 1.61), playing outdoors (OR = 1.32, 95 % CI: 1.16 - 1.50) and increment in the economic status (OR = 1.37, 95 % CI: 1.18 - 1.60). Conclusion Major risk predictors of burn injuries among the Iranian population included childhood ADHD, child’s age, watching television, playing outdoors, high economic status and flammable clothing

    Evaluation of the relationship between serum lactate and potassium levels with clinical signs of calf diarrhea syndrome in calves referred to the large animal clinic of Islamic Azad University of Tabriz Branch

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    Diarrhea in newborn calves is often accompanied by metabolic acidosis which is the main reason for the establishment of symptoms related to diarrhea syndrome such as lethargy, recumbency, decreased suckling strength and etc. In order to be informed of lactic acid levels in the blood of diarrheaic calves, samples were collected from 100 affected and 20 healthy calves as the control group referred to the large animal clinic. In this respect, 120 blood samples were collected from the jugular vein using Venoject tubes, their sera separated by centrifugation and stored at -20°C in micro tubes and lactic acid levels were determined by enzymatic method. In this study, mean lactic acid levels of 4.72±0.02 mmol/lit and 1.2±0.05 mmol/lit were recorded in diarrheaic and healthy calves. Also, mean potassium levels in healthy and diarrheaic calves were 4.20±0.03 mmol/lit and 6.70±0.01 mmol/lit respectively. The results of the present study indicated that there was a significant relationship between diarrheaic and serumic levels of lactic acid and potassium (

    Adjunctive treatment with aripiprazole for risperidone-induced hyperprolactinemia

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    Fatemeh Ranjbar,1 Homayoun Sadeghi-Bazargani,2,3 Parisa Niari Khams,1 Asghar Arfaie,1 Azim Salari,4 Mostafa Farahbakhsh1 1Clinical Psychiatry Research Center, Tabriz University of Medical Sciences, Tabriz, East Azerbaijan, Iran; 2Road Traffic Injury Research Center, Department of Statistics & Epidemiology, Tabriz University of Medical Sciences, Tabriz, Iran; 3World Health Organization Collaborating Center on Community Safety Promotion, Karolinska Institute, Stockholm, Sweden; 4Emam Khomeini Hospital, Naghadeh, West Azerbaijan, Iran Background: Antipsychotics have been used for more than 50 years in the treatment of schizophrenia and many other psychiatric disorders. Prolactin levels usually increase in patients treated with risperidone. Aripiprazole, which has a unique effect as an antipsychotic, is a D2 receptor partial agonist. It is an atypical antipsychotic with limited extrapyramidal symptoms. Since it acts as an antagonist in hyperdopaminergic conditions and as an agonist in hypodopaminergic conditions, it does not have adverse effects on serum prolactin levels. The present study aimed to investigate the effect of aripiprazole on risperidone-induced hyperprolactinemia. Methods: This before-and-after clinical trial was performed in 30 patients. Baseline prolactin levels were measured in all patients who were candidates for treatment with risperidone. In subjects with elevated serum prolactin, aripiprazole was added to their treatment. Serum prolactin levels were measured during the first week, second week, and monthly thereafter for at least 3 months or until prolactin levels became normal. The data were analyzed using Stata version 11 software. Survival analysis and McNemar’s test were also performed. Results: The mean age of the participants was 30.8 years. Prolactin levels normalized in 23 (77%) participants during the study, and menstrual disturbances normalized in 25 (83.3%). Prolactin levels normalized in most patients between days 50 and 110. The median time to recovery based on normalization of prolactin was 84 days. Psychotic symptoms were present in 26 subjects at baseline, but in only two by the end of the study. Conclusion: The results of this study confirm the effects of aripiprazole in reducing risperidone-induced hyperprolactinemia and its sequelae. Aripiprazole also led to significant improvements in psychotic symptoms when compared with those present prior to treatment with aripiprazole. Keywords: hyperprolactinemia, aripiprazole, risperidone, psychotic disorde

    Optimised mixing and flow resistance during shear flow over a rib roughened boundary

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    A series of numerical investigations has been performed to study the effect of lower boundary roughness on turbulent flow in a two-dimensional channel. The roughness spacing to height ratio, w/k, has been investigated over the range 0.12 to 402 by varying the horizontal rib spacing. The square roughness elements each have a cross-sectional area of (0.05 H)2, where H is the full channel height. The Reynolds number, Reτ is fixed based on the value of the imposed pressure gradient, dp/dx, and is in the range 6.3 × 103 − 4.5 × 104. A Reynolds Averaged Navier–Stokes (RANS) based turbulence modelling approach is adopted using a commercial CFD code, ANSYS-CFX 14.0. Measurements of eddy viscosity and friction factor have been made over this range to establish the optimum spacings to produce maximum turbulence enhancement, mixing and resistance to flow. These occur when w/k is approximately 7. It is found that this value is only weakly dependent on Reynolds number, and the decay rate of turbulence enhancement as a function of w/k ratio beyond this optimum spacing is slow. The implications for heat transfer design optimisation and particle transport are considered

    P.150 The Canadian Medical Student Interest Group in Neurosurgery (CaMSIGN) platform: a retrospective study on Canadian medical students

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    Background: The Canadian Medical Student Interest Group in Neurosurgery (CaMSIGN) is the first neurosurgery platform of its kind in Canada. Methods: In this retrospective study, data from CaMSIGN’s online platforms have been collated from February 2021 to the present and analyzed to show trends in user engagement. Results: CaMSIGN events generated 1,575 views on YouTube (384 from Canada). The total watch time was 170.3 hours, of which 43.9 hours were Canadian (28.5%). The total views normalized by the total number of students interested in neurosurgery was 17.12 hours. The normalized Canadian view was 4.17. 717 people follow the CaMSIGN Facebook account (normalized= 7.79). 152 people follow our Instagram (normalized= 1.65). 338 people follow our Twitter (normalized= 3.67). This number is comparable to that of estimated practicing neurosurgeons in Canada (333). A total of 32,974 people visited the Twitter page, with a monthly average of 2747.8. Lastly, the campaign website has had 5,811 visitors since its launch in June 2021 with a monthly average of 695.57 visitors. The number of website visitors has increased at a rate of 3.1327 visitors/month. Conclusions: Through this initiative, our aim has been to model a pan-Canadian approach to neurosurgery. </jats:p

    Awake craniotomy during pregnancy: A systematic review of the published literature

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    Neurosurgical pathologies in pregnancy pose significant complications for the patient and fetus, and physiological stressors during anesthesia and surgery may lead to maternal and fetal complications. Awake craniotomy (AC) can preserve neurological functions while reducing exposure to anesthetic medications. We reviewed the literature investigating AC during pregnancy. PubMed, Scopus, and Web of Science databases were searched from the inception to February 7th, 2023, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Studies in English investigating AC in pregnant patients were included in the final analysis. Nine studies composed of nine pregnant patients and ten fetuses (one twin-gestating patient) were included. Glioma was the most common pathology reported in six (66.7%) patients. The frontal lobe was the most involved region (4 cases, 44.4%), followed by the frontoparietal region (2 cases, 22.2%). The awake-awake-awake approach was the most common protocol in seven (77.8%) studies. The shortest operation time was two hours, whereas the longest one was eight hours and 29 min. The mean gestational age at diagnosis was 13.6 ± 6.5 (2—22) and 19.6 ± 6.9 (9—30) weeks at craniotomy. Seven (77.8%) studies employed intraoperative fetal heart rate monitoring. None of the AC procedures was converted to general anesthesia. Ten healthy babies were delivered from patients who underwent AC. In experienced hands, AC for resection of cranial lesions of eloquent areas in pregnant patients is safe and feasible and does not alter the pregnancy outcome. © 2023, The Author(s)
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