Comparative study on performance accuracy of three probe and five probe flow analysers for wind tunnel testing

In the field of inviscid fluid flow studies, the theoretical concept has to be developed even more. In order to make it possible, it is very important to supplement the concepts with strong experimental results. While performing experimentation, various accepts of design can be determined with factors influencing the and also required modification can be recommended in a more systematic and economic manner. Also, the aim objective of the experiment is to extend the underlying theory and to produce new designs with improvements that can be great support to the advancement in technology. In experimental analysis, wind tunnels are used for the flow analysis over a flying object to be tested. Analyzing the flow plays a predominant role in aerodynamics study. The flow in the test section has to be uniformly streamlined and need to be parallel to the axis of the wind tunnel. The change in flow properties inside the tunnel with respect to the time should be negligible. So, before conducting a test process, calibration of wind tunnel has to be done. Normally, calibration of the subsonic wind tunnel is done by the Pitot static tube. It has the limitations of deprived accuracy and misalignment of the probe with the flow direction. Therefore, new calibrating instruments are proposed by overcoming the limitations of the Pitot static tube. In this paper, experimentation using wind tunnels has been discussed and the truth flow analysis of a low-speed open-circuit wind tunnel has been recorded using two different instruments namely three probe flow analyser and five probe flow analyser respectively. Also, the results obtained have been compared with the data obtained using a pitot static probe

Experimental and Computational Evaluation of Five Hole Five Probe Flow Analyzer for Subsonic Wind Calibration

It is very essential to predict the flow and its related parameters to understand real life fluid flow. The real-life fluid problems are studied with wind tunnels which gives very efficient results in practice. But in the case of wind tunnel studies flow angularities plays crucial role. Flow angularity determination includes measurement of static pressure, dynamic pressure and inflow angles. Flow prediction even hold a very strong hand in design process. Designing and testing being the foundation of any process industry, flow measurements and its related parameters have to be well evaluated. In such cases, wind tunnels play important role and the researchers are usually dependent on wind tunnels to carry out experiments at different Mach numbers to obtain experimental results. It is mandatory to check the flow parameters and maturity rates including turbulence, flow angularity, strain, velocity, temperature and density distribution at the test section before testing a model. The flow field and degree of maturity within the test section can be analysed with any instrument that will provide a flow field data diagram of test parts. In this paper, the performance evaluation and truthiness of five-hole five probe flow analyser is being evaluated computationally and experimentally at various Mach Numbers

Factors influencing place of delivery : evidence from three south-Asian countries

Background High maternal mortality is still a significant public health challenge in many countries of the South-Asian region. The majority of maternal deaths occur due to pregnancy and deliveryrelated complications, which can mostly be prevented by safe facility delivery. Due to the paucity of existing evidence, our study aimed to examine the factors associated with place of delivery, including women's preferences for such in three selected South-Asian countries. Methods We extracted data from the most recent demographic and health surveys (DHS) conducted in Bangladesh (2014), Nepal (2016), and Pakistan (2017-18) and analyzed to identify the association between the outcome variable and socio-demographic characteristics. A total of 16,429 women from Bangladesh (4278; mean age 24.57 years), Nepal (3962; mean age 26.35 years), and Pakistan (8189; mean age 29.57 years) were included in this study. Following descriptive analyses, bivariate and multivariate logistic regressions were conducted. Results Overall, the prevalence of facility-based delivery was 40%, 62%, and 69% in Bangladesh, Nepal, and Pakistan, respectively. Inequity in utilizing facility-based delivery was observed for women in the highest wealth quintile. Participants from Urban areas, educated, middle and upper household economic status, and with high antenatal care (ANC) visits were significantly associated with facility-based delivery in all three countries. Interestingly, watching TV was also found as a strong determinant for facility-based delivery in Bangladesh (aOR = 1.31, 95% CI:1.09-1.56, P = 0.003), Nepal (aOR = 1.42, 95% CI:1.20-1.67, P<0.001) and Pakistan (aOR = 1.17, 95% CI: 1.03-1.32, P = 0.013). Higher education of husband was a significant predictor for facility delivery in Bangladesh (aOR = 1.73, 95% CI:1.27-2.35, P = 0.001) and Pakistan (aOR = 1.19, 95% CI: 0.99-1.43, P = 0.065); husband's occupation was also a significant factor in Bangladesh (aOR = 1.30, 95% CI:1.04-1.61, P = 0.020) and Nepal (aOR = 1.26, 95% CI:1.01-1.58, P = 0.041). Conclusion Our findings suggest that the educational status of both women and their husbands, household economic situation, and the number of ANC visits influenced the place of delivery. There is an urgent need to promote facility delivery by building more birthing facilities, training and deployment of skilled birth attendants in rural and hard-to-reach areas, ensuring compulsory female education for all women, encouraging more ANC visits, and providing financial incentives for facility deliveries. There is a need to promote facility delivery by encouraging health facility visits through utilizing social networks and continuing mass media campaigns. Ensuring adequate Government funding for free maternal and newborn health care and local community involvement is crucial for reducing maternal and neonatal mortality and achieving sustainable development goals in this region. © 2021 Rahman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. *Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Muhammad Rahman” is provided in this record*

Spontaneous Perforation of a Choledochal Cyst, Clues for Diagnosis

Aim: Spontaneous perforation is a rare complication of a choledochal cyst that is difficult to diagnose because of its nonspecific clinical presentation. These patients usually present with an insidious course characterized by progressive abdominal distension, vomiting, and pain. Here, we present a series of three cases for clues for diagnosis.Materials and methods: All patients with spontaneous perforation of a choledochal cyst who were presented to our institute from January 2009 to December 2011 were included in the study and symptoms and signs at the time of presentation were analyzed.Results: All patients had clinical jaundice and acholic stools at the time of presentation; pain and vomiting was not a consistent feature. Abdominal paracentesis helped us diagnose these cases.Conclusion: Abdominal paracentesis is very useful in cases of suspected spontaneous perforation of the bile duct. Simple drainage with a T-tube, if possible, is safe, efficacious, has low morbidity, and aids in the establishment of the diagnosis as well as delineation of the anatomy of the concerned region for definitive surgery.Keywords: Choledochal Cyst, Spontaneous Perforation of Bile Duct, T-tub

Feasibility of right-sided total extraperitoneal procedure for inguinal hernia repair after appendectomy: a prospective cohort study

Contains fulltext : 80682.pdf (publisher's version ) (Open Access)BACKGROUND: Totally extraperitoneal (TEP) endoscopic hernia surgery is increasingly popular since it is associated with little postoperative pain and with early return to work. Previous appendectomy may preclude preperitoneal dissection in patients with right-sided hernias. The feasibility of TEP surgery in these patients was the subject of the present study. METHODS: Between January 2005 and February 2007 all consecutive patients undergoing TEP surgery were included in a prospective cohort study. The study group consisted of patients with right-sided and bilateral hernias. Operative times, conversions, complication rates, and return to daily activities were recorded. Patients were divided into two groups according to previous appendectomy. RESULTS: A total of 462 patients with right-sided hernias underwent TEP surgery: 421 patients without previous abdominal surgery (group 1) and 41 patients with previous appendectomy (group 2). The conversion rate was significantly higher in group 2: four patients (10%) were converted to open Lichtenstein repair versus five (1%) in group 1 (p = 0.005). However, we found no significant differences in complication rate, operative time, and return to daily activities. CONCLUSIONS: A right-sided (or bilateral) TEP procedure may be performed safely in patients after previous appendectomy. Despite a higher conversion rate, the vast majority of patients can be operated endoscopically

A meta-analysis of long-term effects of conservation agriculture on maize grain yield under rain-fed conditions

Conservation agriculture involves reduced tillage, permanent soil cover and crop rotations to enhance soil fertility and to supply food from a dwindling land resource. Recently, conservation agriculture has been promoted in Southern Africa, mainly for maize-based farming systems. However, maize yields under rain-fed conditions are often variable. There is therefore a need to identify factors that influence crop yield under conservation agriculture and rain-fed conditions. Here, we studied maize grain yield data from experiments lasting 5 years and more under rain-fed conditions. We assessed the effect of long-term tillage and residue retention on maize grain yield under contrasting soil textures, nitrogen input and climate. Yield variability was measured by stability analysis. Our results show an increase in maize yield over time with conservation agriculture practices that include rotation and high input use in low rainfall areas. But we observed no difference in system stability under those conditions. We observed a strong relationship between maize grain yield and annual rainfall. Our meta-analysis gave the following findings: (1) 92% of the data show that mulch cover in high rainfall areas leads to lower yields due to waterlogging; (2) 85% of data show that soil texture is important in the temporal development of conservation agriculture effects, improved yields are likely on well-drained soils; (3) 73% of the data show that conservation agriculture practices require high inputs especially N for improved yield; (4) 63% of data show that increased yields are obtained with rotation but calculations often do not include the variations in rainfall within and between seasons; (5) 56% of the data show that reduced tillage with no mulch cover leads to lower yields in semi-arid areas; and (6) when adequate fertiliser is available, rainfall is the most important determinant of yield in southern Africa. It is clear from our results that conservation agriculture needs to be targeted and adapted to specific biophysical conditions for improved impact

Biogenesis of the inner membrane complex is dependent on vesicular transport by the alveolate specific GTPase Rab11B

Apicomplexan parasites belong to a recently recognised group of protozoa referred to as Alveolata. These protists contain membranous sacs (alveoli) beneath the plasma membrane, termed the Inner Membrane Complex (IMC) in the case of Apicomplexa. During parasite replication the IMC is formed de novo within the mother cell in a process described as internal budding. We hypothesized that an alveolate specific factor is involved in the specific transport of vesicles from the Golgi to the IMC and identified the small GTPase Rab11B as an alveolate specific Rab-GTPase that localises to the growing end of the IMC during replication of Toxoplasma gondii. Conditional interference with Rab11B function leads to a profound defect in IMC biogenesis, indicating that Rab11B is required for the transport of Golgi derived vesicles to the nascent IMC of the daughter cell. Curiously, a block in IMC biogenesis did not affect formation of sub-pellicular microtubules, indicating that IMC biogenesis and formation of sub-pellicular microtubules is not mechanistically linked. We propose a model where Rab11B specifically transports vesicles derived from the Golgi to the immature IMC of the growing daughter parasites

A Note on Vectorial AdS5_5/CFT4_4 Duality for Spin-jj Boundary Theory

The vectorial holographic correspondences between higher-spin theories in AdS$_5$ and free vector models on the boundary are extended to the cases where the latter is described by free massless spin-$j$ field. The dual higher-spin theory in the bulk does not include gravity and can only be defined on rigid AdS$_5$ background with $S^4$ boundary. We discuss various properties of these rather special higher-spin theories and calculate their one-loop free energies. We show that the result is proportional to the same quantity for spin-$j$ doubleton treated as if it is a AdS$_5$ field. Finally, we consider even more special case where the boundary theory itself is given by an infinite tower of massless higher-spin fields.Comment: 27 pages, version to appear in JHE

No neurocognitive advantage for immediate antiretroviral treatment in adults with greater than 500 CD4+ T-cell counts

OBJECTIVE: To compare the effect of immediate versus deferred antiretroviral treatment (ART) on neuropsychological test performance in treatment-naive HIV-positive adults with >500 CD4+ cells/μL. DESIGN: Randomized trial. METHODS: The START parent study randomized participants to commence immediate versus deferred ART until CD4+ <350 cells/μL. The START Neurology substudy used 8 neuropsychological tests, at baseline, months 4, 8, 12 and annually, to compare groups for changes in test performance. Test results were internally standardized to z-scores. The primary outcome was the average of the eight test z-scores (QNPZ-8). Mean changes in QNPZ-8 from baseline were compared by intent-to-treat using longitudinal mixed models. Changes from baseline to specific time points were compared using ANCOVA models. RESULTS: 592 participants had a median age of 34 years; median baseline CD4+ count of 629 cells/μL; the mean follow-up was 3.4 years. ART was used for 94% and 32% of accrued person-years in the immediate and deferred groups, respectively. There was no difference between the immediate and deferred ART groups in QNPZ-8 change through follow-up [-0.018 (95% CI: -0.062 to 0.027, p = 0.44)], or at any visit. However, QNPZ-8 scores increased in both arms during the first year, by 0.22 and 0.24, respectively (p < 0.001 for increase from baseline). CONCLUSIONS: We observed substantial improvement in neurocognitive test performance during the first year in both study arms, underlining the importance of using a control group in studies assessing neurocognitive performance over time. Immediate ART neither benefitted nor harmed neurocognitive performance in individuals with CD4+ cell counts above 500 cells/μL