Viscous compressible flow direct and inverse computation and illustrations

An algorithm for laminar and turbulent viscous compressible two dimensional flows is presented. For the application of precise boundary conditions over an arbitrary body surface, a body-fitted coordinate system is used in the physical plane. A thin-layer approximation of tne Navier-Stokes equations is introduced to keep the viscous terms relatively simple. The flow field computation is performed in the transformed plane. A factorized, implicit scheme is used to facilitate the computation. Sample calculations, for Couette flow, developing pipe flow, an isolated airflow, two dimensional compressor cascade flow, and segmental compressor blade design are presented. To a certain extent, the effective use of the direct solver depends on the user's skill in setting up the gridwork, the time step size and the choice of the artificial viscosity. The design feature of the algorithm, an iterative scheme to correct geometry for a specified surface pressure distribution, works well for subsonic flows. A more elaborate correction scheme is required in treating transonic flows where local shock waves may be involved

Modulated Exo-Brake Flight Testing - Modeling and Test Results - Successes with Exo-Brake Development and Targeting for Future Sample Return Capability: TES-6,7,8 Flight Experiments

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Evaluation et prise en charge de l’anxiété préopératoire chez l’adulte camerounais

Introduction : L’acte chirurgical et l’anesthésie sont des éléments anxiogènes. Le but du travail était d’évaluer l’anxiété préopératoire vécue par les sujets adultes admis pour chirurgie élective dans trois hôpitaux de la ville de Yaoundé.Méthodologie : Il s’agissait d’une étude prospective et descriptive, durant six mois. Les patients étaient recrutés dans trois hôpitaux de la ville de Yaoundé. Etaient inclus, tous les patients de plus de 15 ans admis en consultation d’anesthésie, programmés pour une chirurgie élective, classés ASA 1 ou 2, comprenant correctement les questionnaires et ayant donné leur consentement éclairé. L’anxiété préopératoire était évaluée par l’échelle d’Hamilton, ses manifestations et sa prise en charge étaient recherchées.Résultats : La population d’étude était de 244 patients : 78% de sexe féminin et 22% de sexe masculin. L’âge moyen était de 40,13 ±15,9 ans. Les patients ASA 1 représentaient 59,8%. L’information reçue du chirurgien n’était pas satisfaisante pour 29,8% des patients. L’information reçue de l’anesthésiste quant à elle n’était pas rassurante dans 13,9% des cas. Les manifestations psychiques de l’anxiété (51,6%) étaient plus fréquentes que les plaintes somatiques (49,4%). Notre étude révélait que 59% des futurs opérés étaient anxieux. Le sexe, la notion de chirurgie antérieure, l’information sur les détails de l’intervention avaient une association significative avec l’anxiété. La prise en charge psychologique était appliquée à tous les patients, l’hydroxyzine était associée chez 10,7% d’entre eux. La réévaluation la veille de l’intervention révélait que 73,6% des anxieux conservaient leur niveau d’anxiété initial, 16,7% avaient des scores plus bas et 9,72% avaient des scores plus élevés.Conclusion : L’anxiété préopératoire des futurs opérés est importante. Une meilleure préparation psychologique est un axe d’amélioration du vécu périopératoire des patients. Mots clés : Evaluation – Pris en charge - Anxiété préopératoire – Adulte   English Title: Assessment and management of preoperative anxiety in Cameroonian adults Introduction: Surgery and anesthesia are anxiety-causing events. Psychological preparation of the patient prior to surgery remains one of the remedies in the management of the preoperative anxiety. The aim of our study was to assess preoperative anxiety experienced by adult patients admitted for elective surgery in three hospitals in the city of Yaoundé. Methods: It was a prospective and descriptive study, which took place during three months. Patients were recruited from the University Teaching Hospital of Yaoundé, Yaoundé Central Hospital and the Yaoundé Gynaeco-Obstetric and Pediatric Hospital. Were included in our study, all the patients above 15 years of age seen in anesthetic consultation, programmed for an elective surgery, classified ASA 1 or 2, who understood the questionnaire and who gave their informed consent. Preoperative anxiety was assessed by the Hamilton’s scale, the clinical features and the treatment were recorded. Results: We retained 244 patients in the study: 78% were female. The mean age was 40.1 ±15.9 years. ASA 1 patients accounted for 59.8%. The information received from the surgeon was not satisfactory to 29.8% of patients. Information received from the anesthetist was not reassuring in 13.9% of cases. The psychic manifestations of anxiety were most frequent (51.6%). Our study revealed that 59% of patients to be operated were anxious. The sex of patients, notion of previous surgery and the information on the details of the surgery had a significant relationship with anxiety. Psychological support by anesthesiologist was applied to all the patients, hydroxyzine was associated in 10.7% of patients. The revaluation on the level of the surgery revealed that 73.6% of the anxious patients remained at their initial anxiety level, 16.7% had lower scores and 9.72% had higher scores. Conclusion: Preoperative anxiety for future patients is important. Better psychological preparation is an axis for improving the perioperative experience of patients. Key-words: Management – Assessment - Preoperative anxiety – Adul

Epidemiology of onchocerciasis-associated epilepsy in the Mbam and Sanaga river valleys of Cameroon : impact of more than 13 years of ivermectin

BackgroundA high epilepsy prevalence has been reported in several onchocerciasis-endemic villages along the Mbam and Sanaga river valleys in Cameroon, including Bilomo and Kelleng. We sought to determine the prevalence of epilepsy in these two villages following more than 13years of community-directed treatment with ivermectin (CDTI).MethodsDoor-to-door surveys were performed on the entire resident population in the villages in August 2017 and January 2018. Epilepsy was diagnosed using a 2-step approach: administration of a standardized 5-item questionnaire followed by confirmation by a neurologist. Previously published diagnostic criteria for onchocerciasis-associated epilepsy (OAE) were used. Ov16 serology was done for children aged 7-10years to assess onchocerciasis transmission. Findings were compared with previous data from these two villages.ResultsA total of 1525 individuals (1321 in Bilomo and 204 in Kelleng) in 233 households were surveyed in both villages. The crude prevalence of epilepsy was 4.6% in Bilomo (2017) and 7.8% in Kelleng (2018), including 12 (15.6% of cases) persons with epilepsy (PWE) with nodding seizures. The age and sex-standardized prevalence in Kelleng decreased from 13.5% in 2004 to 9.3% in 2018 (P<0.001). The median age of PWE shifted from 17 (IQR: 12-22) years to 24 (IQR: 20-30) years in Bilomo (P<0.001); and slightly from 24 (IQR: 14-34) years to 28 (IQR: 21.25-36.75) years in Kelleng (P=0.112). Furthermore, 47.6% of all tested children between 7 and 10years had Ov16 antibodies.ConclusionsThere is a decrease in epilepsy prevalence after 13years and more of CDTI in both villages. The age-shift observed in PWE suggests that ivermectin may prevent OAE in younger residents. Ov16 seropositivity in children indicates ongoing onchocerciasis transmission possibly due to suboptimal control measures. Our findings support the existence of OAE in Cameroon and highlight the need to strengthen onchocerciasis elimination programs

Depressive symptoms in HIV-infected and seronegative control subjects in Cameroon: Effect of age, education and gender

<div><p>Depression is a leading cause of HIV/AIDS disease burden; it worsens health outcomes and quality of life. Addressing this problem requires accurate quantification of the extra burden of depression to HIV/AIDS in a given population, and knowledge of the baseline depression prevalence in the general population. There has been no previous study of depression in the general Cameroonian population. The current study attempts to address that important need. We used the Beck Depression Inventory-II to assess the prevalence and severity of depressive symptoms in 270 HIV-infected and seronegative Cameroonians. Univariate analyses showed a trend toward higher depressive symptoms among cases, compared to controls (p = 0.055), and among older subjects (>40 years), compared to younger subjects (≤40 years) (p = 0.059). Analysis of depression severity showed that 33.73% of cases had moderate-to-severe depressive symptoms, compared to 19.8% of controls (p<0.01). However, multivariable negative binomial regression analyses showed no effect of age, HIV status, CD4 levels, viral loads, ART, or opportunistic infections on the risk of depressive symptoms. Both univariate and multivariable regression analyses showed significantly higher risk of depressive symptoms among females compared to males; this was significant for both female controls and female cases. Female cases had significantly higher CD4 cell counts and lower viral loads, compared to males. Both univariate and multivariable regression analyses showed that lower education (≤10 years) was associated with increased risk of depressive symptoms. This study shows a high prevalence of depressive symptoms among seronegative controls and HIV-infected Cameroonians. Integrating care for mental disorders such as depression into primary health care and existing HIV/AIDS treatment programs in Cameroon may improve the wellbeing of the general population and could lower the HIV/AIDS burden.</p></div

Clinical and laboratory characteristics of HIV-infected subjects: CD4 and viral loads of cases on ART and treatment naïve.

<p>Clinical and laboratory characteristics of HIV-infected subjects: CD4 and viral loads of cases on ART and treatment naïve.</p

Negative binomial regression analysis of depression risks (BDI-II) among Cameroonian subjects: Analysis after withdrawing the interaction term (gender*status).

<p>Negative binomial regression analysis of depression risks (BDI-II) among Cameroonian subjects: Analysis after withdrawing the interaction term (gender*status).</p

Univariate analysis of depression risks (BDI-II) among Cameroonian subjects.

<p>Univariate analysis of depression risks (BDI-II) among Cameroonian subjects.</p

Negative binomial regression analysis of depression risks (BDI-II) among Cameroonian subjects: Analysis based on Beck FS scores.

<p>Negative binomial regression analysis of depression risks (BDI-II) among Cameroonian subjects: Analysis based on Beck FS scores.</p