Effect of wall cooling on the stability of compressible subsonic flows over smooth humps and backward-facing steps

The effect of wall cooling on the two-dimensional linear stability of subsonic flows over two-dimensional surface imperfections is investigated. Results are presented for flows over smooth humps and backward-facing steps with Mach numbers up to 0.8. The results show that, whereas cooling decreases the viscous instability, it increases the shear-layer instability and hence it increases the growth rates in the separation region. The coexistence of more than one instability mechanism makes a certain degree of wall cooling most effective. For the Mach numbers 0.5 and 0.8, the optimum wall temperatures are about 80 pct and 60 pct of the adiabatic wall temperature, respectively. Increasing the Mach number decreases the effectiveness of cooling slightly and reduces the optimum wall temperature

The influence of circulating anti-Müllerian hormone on ovarian responsiveness to ovulation induction with gonadotrophins in women with polycystic ovarian syndrome: a pilot study

Background Women with polycystic ovarian syndrome (PCOS) are known to have elevated circulating Anti-Müllerian hormone (AMH), which has been found to desensitize ovarian follicles to follicle stimulating hormone (FSH). The purpose of this study was to investigate the impact of high circulating AMH on ovarian responsiveness to ovulation induction with gonadotrophins in PCOS women. Methods This prospective observational pilot study was conducted in two collaborating Fertility Centres in the UK and Egypt. The study included 20 consecutive anovulatory women with PCOS who underwent 34 cycles of human menopausal gonadotrophin (hMG) ovarian stimulation using chronic low-dose step up protocol. Blood samples were collected for the measurement of serum AMH concentrations in the early follicular (day 2-3) phase in all cycles of hMG treatment. The serum levels of AMH were compared between cycles with good vs. poor response. The good response rates and the total dose and duration of hMG treatment were compared between cycles with high vs. low serum AMH concentrations. Results Cycles with poor response (no or delayed ovulation requiring >20 days of hMG treatment) had significantly (p = .007) higher median{range} serum AMH concentration (6.5{3.2-13.4}ng/ml) compared to that (4.0{2.2-10.2}ng/ml) of cycles with good response (ovulation within 20 days of hMG treatment). ROC curve showed AMH to be a useful predictor of poor response to hMG stimulation (AUC, 0.772; P = 0.007). Using a cut-off level of 4.7 ng/ml, AMH had a sensitivity of 100% and specificity of 58% in predicting poor response. The good response rate was significantly (p  = 4.7 ng/ml (100% vs. 35%, respectively). All cycles with markedly raised serum AMH levels (> 10.2 ng/ml) were associated with poor response. Cycles with high AMH (> = 4.7 ng/ml) required significantly (p < .001) greater amounts (median {range}, 1087{450-1650}IU) and longer duration (20 {12-30}days) of hMG stimulation than cycles with lower AMH (525 {225-900}IU and 8{6-14}days). Conclusions PCOS women with markedly raised circulating AMH seem to be resistant to hMG ovulation induction and may require a higher starting dose

Potentiometric detection of low-levels of sulfamethazine in milk and pharmaceutical formulations using novel plastic membrane sensors

Novel potentiometric sensors for selective screening of sulfamethazine (SMZ) in pharmaceutical preparations and milk samples are reported. The sensor membranes were made from PVC matrix doped with magnesium(II)-, manganese(II)- and dichlorotin (IV)-phthalocyanines as ionophores and aliquat-336 and nitron/SMZ ion-pair complex as ion exchangers. These sensors revealed fast, stable and near-Nernstian anionic response for the singly charged sulfamethazine anion over the concentration range 10-2 - 10-5 M. The sensors exhibited good selectivity towards SMZ over most known anions, excipients and diluents commonly added in drug preparations. Validation of the proposed methods was demonstrated via evaluating the detection limit, linear response range, accuracy, precision (within-day repeatability) and between-day-variability. The sensors are easily interfaced with a double channel flow injection system and used for continuous monitoring of SMZ in drug formulations, spiked milk samples and biological tissues. The method offers the advantages of design simplicity, results accuracy, and automation feasibility

Fabrication of sulfonated polyethersulfone ultrafiltration membranes with an excellent antifouling performance by impregnating with polysulfopropyl acrylate coated ZnO nanoparticles

Sulfonated polyethersulfone/sulfopropyl methacrylate membranes impregnated with the polysulfopropyl acrylate coated ZnO nanoparticles were developed using a non-solvent-induced phase separation recipe. The composite membranes offered much-enhanced hydrophilicity and improved porosity, which are critical for the excellent antifouling performance and high permeate flux. By adding polysulfopropyl acrylate modified ZnO, it achieved the maximum water flux of 420 Lm−2h−1 while maintained the natural organic matter rejection rate of 99% with an excellent flux recovery ratio up to 99% in the antifouling measurement. The results display that the impregnation of ZnO nanoparticles in the sulfonated polyethersulfone membrane can effectively increase the surface hydrophilicity which is essential for reducing the irreversible fouling with improved long-term performance and excellent recyclability

Guillain-Barre syndrome associated with COVID-19 infection:A case series

In this communication, we reported a series of six patients presented with Guillain-Barré syndrome that associated with COVID-19 infection, which was confirmed with RT-PCR. Here we discuss the laboratory investigation and case management, as well as clinical presentation and outcome of each case. The current report demonstrated the first case series of COVID-19-associated GBS-cases in Sudan.</p

Risk Assessment Of In-Vitro Fertilization, Review Article

Since its remarkable inception in 1978, IVF&nbsp;has garnered significant public interest.&nbsp;&nbsp; Currently, assisted reproductive technology is widely accessible in most developed countries, and the methods employed have significantly evolved since its inception.&nbsp;&nbsp; Advancements in laboratory technology and clinical practice have enabled IVF to develop into a medical process that is highly efficient, safe, easily accessible, and comparatively affordable. Over 2 million children conceived by&nbsp;IVF&nbsp;have been born so far, and it is probable that ongoing improvements will increase its attractiveness and suitability. There has been a rising interest in the topic of risk assessment in IVF in recent years, with a significant amount of research focused on detecting and reducing the potential dangers linked to the operation.&nbsp;&nbsp; This review article seeks to offer a thorough and all-encompassing analysis of the present understanding of risk assessments in IVF, encompassing the diverse range of risks and complications linked to the operation

GRFS and CRFS in alternative donor hematopoietic cell transplantation for pediatric patients with acute leukemia.

We report graft-versus-host disease (GVHD)-free relapse-free survival (GRFS) (a composite end point of survival without grade III-IV acute GVHD [aGVHD], systemic therapy-requiring chronic GVHD [cGVHD], or relapse) and cGVHD-free relapse-free survival (CRFS) among pediatric patients with acute leukemia (n = 1613) who underwent transplantation with 1 antigen-mismatched (7/8) bone marrow (BM; n = 172) or umbilical cord blood (UCB; n = 1441). Multivariate analysis was performed using Cox proportional hazards models. To account for multiple testing, P \u3c .01 for the donor/graft variable was considered statistically significant. Clinical characteristics were similar between UCB and 7/8 BM recipients, because most had acute lymphoblastic leukemia (62%), 64% received total body irradiation-based conditioning, and 60% received anti-thymocyte globulin or alemtuzumab. Methotrexate-based GVHD prophylaxis was more common with 7/8 BM (79%) than with UCB (15%), in which mycophenolate mofetil was commonly used. The univariate estimates of GRFS and CRFS were 22% (95% confidence interval [CI], 16-29) and 27% (95% CI, 20-34), respectively, with 7/8 BM and 33% (95% CI, 31-36) and 38% (95% CI, 35-40), respectively, with UCB (P \u3c .001). In multivariate analysis, 7/8 BM vs UCB had similar GRFS (hazard ratio [HR], 1.12; 95% CI, 0.87-1.45; P = .39), CRFS (HR, 1.06; 95% CI, 0.82-1.38; P = .66), overall survival (HR, 1.07; 95% CI, 0.80-1.44; P = .66), and relapse (HR, 1.44; 95% CI, 1.03-2.02; P = .03). However, the 7/8 BM group had a significantly higher risk for grade III-IV aGVHD (HR, 1.70; 95% CI, 1.16-2.48; P = .006) compared with the UCB group. UCB and 7/8 BM groups had similar outcomes, as measured by GRFS and CRFS. However, given the higher risk for grade III-IV aGVHD, UCB might be preferred for patients lacking matched donors. © 2019 American Society of Hematology. All rights reserved

Coexistence of HBsAg/Anti-HBs and HBeAg/Anti-HBe in Sudanese Patients with Chronic Hepatitis B Virus Infection: A Cross-Sectional Study

Background: Seroconversion of hepatitis B surface antigen (HBsAg) to hepatitis B surface antibody (anti-HBs) is a recognized goal of HBV therapy. This dynamic transition responsible for the coexistence of HBsAg and anti-HBs is rarely detected in clinical cases. However, with vaccination and the use of various antiviral drugs, as well as the development of new medical technologies, recognizing the coexistence of HBsAg and anti-HBs has become more common. In addition, mutations in viral genomes, immune status, and human genetic factors may also contribute to such coexistence. The current study was designed to determine the prevalence of the coexistence of HBsAg and anti-HBs and HBeAg and anti-HBe in CHB patients in Sudan. Methods and Results: This was a descriptive cross-sectional study conducted in Khartoum state from November 2018 to January 2019. The study included 70 HBV-infected patients who were positive for HBsAg for more than six months. Blood samples were tested for HBsAg/Anti-HBs and HBeAg/Anti-HBe using Commercial ELISA Kits (Foresight, United Kingdom) and (PRECHEK, USA). Demographic data were collected using a structured questionnaire, and any antiviral agent and laboratory results were also recorded for each participant. The current study showed that one case (1.4%) was reactive for the coexistence of HBsAg/HBsAb and two cases (2.8%) for the coexistence of HBeAg/HBeAb. There was no statistical difference between the coexistence of HBsAg/HBsAb and HBeAg/HBeAb with age, gender, residence, and treatment status. Conclusion: Our study indicates that the frequencies of the coexistence of HBsAg/HBsAb and HBeAg/HBeAb among Sudanese patients with chronic HBV infection were low compared to previous studies in a different population

Myeloablative vs Reduced-Intensity Conditioning Allogeneic Hematopoietic Cell Transplantation for Chronic Myeloid Leukemia

Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment of chronic myeloid leukemia (CML). Optimal conditioning intensity for allo-HCT for CML in the era of tyrosine kinase inhibitors (TKIs) is unknown. Using the Center for International Blood and Marrow Transplant Research database, we sought to determine whether reduced-intensity/nonmyeloablative conditioning (RIC) allo-HCT and myeloablative conditioning (MAC) result in similar outcomes in CML patients. We evaluated 1395 CML allo-HCT recipients between the ages of 18 and 60 years. The disease status at transplant was divided into the following categories: chronic phase 1, chronic phase 2 or greater, and accelerated phase. Patients in blast phase at transplant and alternative donor transplants were excluded. The primary outcome was overall survival (OS) after allo-HCT. MAC (n = 1204) and RIC allo-HCT recipients (n = 191) from 2007 to 2014 were included. Patient, disease, and transplantation characteristics were similar, with a few exceptions. Multivariable analysis showed no significant difference in OS between MAC and RIC groups. In addition, leukemia-free survival and nonrelapse mortality did not differ significantly between the 2 groups. Compared with MAC, the RIC group had a higher risk of early relapse after allo-HCT (hazard ratio [HR], 1.85; P = .001). The cumulative incidence of chronic graft-versus-host disease (cGVHD) was lower with RIC than with MAC (HR, 0.77; P = .02). RIC provides similar survival and lower cGVHD compared with MAC and therefore may be a reasonable alternative to MAC for CML patients in the TKI era