A new explicit sequentially coupled technique for chemo-thermo-poromechanical modelling and simulation in shale formations

The authors would like to acknowledge the Petroleum Technology Development Fund for sponsoring this research.Peer reviewedPublisher PD

Mitral Valve Replacement Surgery in Redo Patients with Mix Blood Cardioplegia (MBC) Protection

Aim of Study: Redo patient undergoing valve surgery are always a challenge for both cardiac surgeon and anesthesiologists. Mix blood cardioplegia has had a profound impact on cardiac surgery. but there have been few studies on its use in mitral valve replacement, especially in redo patient. The purpose of this study was to determine whether mix blood cardioplegia offers any advantages in redo patient undergoing mitral valve replacement.Patients and Methods:  20 patient, who have had a previous mitral valve surgery and were scheduled for mitral valve replacement with or without tricuspid repair, were randomized retrospectively to one of two groups of 10 with different technique of myocardial protection: group A (10 patients) had cold crystalloid cardioplegia, and group B(10 patients) had mix blood cardioplegia, a technique modified on our clinic condition (made by mixing  400-500ml oxygenated blood from oxygenator  and 10ml KCL 7.5%) . Systemic hypothermia was 28°C in Group A and between 32°C and 33°C in Group B. The results were primarily assessed on the basis of clinical outcome, such as hematocrit level intra and post CPB, maximum dose of inotropic support, spontaneous rhythm recovery after aortic cross clamping, length of intensive care unit stay and secondly on postoperative blood loss and blood requirements. Results: There were no preoperative or operative differences between the groups with regard to age, sex, diagnosis, rhythm, New York Heart Association functional class, left ventricular ejection fraction, estimated pulmonary artery systolic pressure, operation, or duration of the operation, CPB, or aortic cross clamping and the time when the patients underwent the first operation. There was one death in group A (10% mortality). The changes in hematocrit level differs significantly between the two groups on the post CPB period (p=0,02) There appeared to be a trend towards better spontaneous recovery of sinus rhythm after removal of the aortic cross clamp in group B compared with group A, the difference did reach statistical significance. (p=0.002). Patients on group A required more inotropic support than Group B (p=0.005). There were differences even on blood requirements postoperatively, more dominant these  requirement were in group A (p=0.02).Discussion: Mix Blood Cardioplegia had beneficial effects in clinical outcome in redo patients undergoing mitral valve replacement surgery. This may be due to its better preservation of high-energy phosphates and endogenous amino acids, less anerobic metabolic activity on reperfusion, reduced release of cardiac troponin T, and improved post-ischemic functional recovery. Keywords: Miocardial protection, cardiopulmonary bypass CPB, Mix Blood Cardioplegia (MBC) DOI: 10.7176/ALST/82-04 Publication date:October 31st 202

Isolation and molecular identification of yeast strains from “Rabilé” a starter of local fermented drink

“Rabilé” is dried yeast harvested from Sorghum beer, used as a traditional starter culture but more especially as ingredient in sauce and food cooking in Burkina Faso. The present study aimed to isolate and identify indigenous yeast flora of “Rabilé”. Standard microbiological process was carried out to value and isolate yeast in different samples of “Rabilé” coming from four localities of Burkina Faso. Phenotypical method and molecular method (PCR and RFLP) were used for yeast  strains characterization and identification. The results showed that yeast counts ranged from 9.49 to 10.35 log cfu/g of “Rabilé”. A total of twenty yeast strains were isolated. Based on phenotypical characters three genera were detected: Candida (40%), Saccharomyces (35%) and Rhodotorula (25%). Molecular identification revealed two specific strains among yeasts isolated as S. cerevisiae with a frequency of 35% and R. mucilaginosa with a frequency of 25%. This data highlights the diversity of indigenous yeast flora of “Rabilé”.Key words: Rabilé, yeast, polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), traditional starter culture

Potential of Malawi’s medicinal plants in Covid-19 disease management: A review

The Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered an international pandemic that has led to significant public health problems. To date, limited evidence exists to suggest that drugs are effective against the disease. As possible treatments are being investigated, herbal medicines have shown potential for producing novel antiviral agents for the COVID-19 disease. Aim This review explored the potential of Malawi’s traditional medicinal plants for the management of COVID-19. MethodsThe authors searched on PubMed and Google scholar for medicinal plants that are used in Malawi and published in openly available peer reviewed journals. Plants linked with antiviral treatment, anti-COVID-19 activity or COVID-19 symptoms management were targeted. These included activity against pneumonia, inflammation, cough, difficulty in breathing, pain/aches, fever, diarrhoea, rheumatism, fatigue, asthma, immunocompromised and cardiovascular diseases.Results11 studies were found with 306 plant species. 127 plant species had at least one COVID-19 related pharmacological activity. Of these plant species, the number of herbal entities used for each indication was: pain/aches (87), fever (2), pneumonia (9), breathing/asthma problems (5), coughing (11), diarrhoea (1), immunosuppression (8), blood issues (10), fatigue (2), heart problems (11), inflammation (8), rheumatism (10) and viral diseases (12). Thirty (30) species were used for more than one disease and Azedarachta indica topped the list (6 of the 13 COVID-19 related diseases). The majority of the species had phytochemicals known to have antiviral activity or mechanisms of actions linked to COVID-19 and consequent diseases’ treatment pathways.ConclusionMedicinal plants are a promising source of compounds that can be used for drug development of COVID-19 related diseases. This review highlights potential targets for the World Health Organization and other research entities to explore in order to assist in controlling the pandemic

Temperature Dependence of GaN HEMT Small Signal Parameters

This study presents the temperature dependence of small signal parameters of GaN/SiC HEMTs across the 0–150°C range. The changes with temperature for transconductance (m), output impedance (ds and ds), feedback capacitance (dg), input capacitance (gs), and gate resistance (g) are measured. The variations with temperature are established for m, ds, ds, dg, gs, and g in the GaN technology. This information is useful for MMIC designs

Tolerance of Gambian Plasmodium falciparum to Dihydroartemisinin and Lumefantrine Detected by Ex Vivo Parasite Survival Rate Assay.

Monitoring of Plasmodium falciparum sensitivity to antimalarial drugs in Africa is vital for malaria elimination. However, the commonly used ex vivo/in vitro 50% inhibitory concentration (IC50) test gives inconsistent results for several antimalarials, while the alternative ring-stage survival assay (RSA) for artemisinin derivatives has not been widely adopted. Here, we applied an alternative two-color flow cytometry-based parasite survival rate assay (PSRA) to detect ex vivo antimalarial tolerance in P. falciparum isolates from The Gambia. The PSRA infers parasite viability by quantifying reinvasion of uninfected cells following 3 consecutive days of drug exposure (10-fold the IC50 of drug for field isolates). The drug survival rate is obtained for each isolate from the slope of the growth/death curve. We obtained parasite survival rates of 41 isolates for dihydroartemisinin (DHA) and lumefantrine (LUM) out of 51 infections tested by ring-stage survival assay (RSA) against DHA. We also determined the genotypes for known drug resistance genetic loci in the P. falciparum genes Pfdhfr, Pfdhps, Pfmdr, Pfcrt, and Pfk13 The PSRA results determined for 41 Gambian isolates showed faster killing and lower variance after treatment with DHA than after treatment with LUM, despite a strong correlation between the two drugs. Four and three isolates were tolerant to DHA and LUM, respectively, with continuous growth during drug exposure. Isolates with the PfMDR1-Y184F mutant variant showed increased LUM survival, though the results were not statistically significant. Sulfadoxine/pyrimethamine (SP) resistance markers were fixed, while all other antimalarial variants were prevalent in more than 50% of the population. The PSRA detected ex vivo antimalarial tolerance in Gambian P. falciparum This calls for its wider application and for increased vigilance against resistance to artemisinin combination therapies (ACTs) in this population

Factors Influencing Early Retirement : Am I Ready?

This study applies the main issues identified to influence early retirement and a decisionmaking process leading from retirement thoughts to retirement plans and from retirement plans to actual retirement. Early retirement plans are highly personalized decision, and it is an individual’s opinion on their short term or long-term plan and need to be regarded distinctive. Early retirement can be thought to represent the effect of unobservable characteristics on retirement, such as preference and motivation. Several key factors are associated with early retirement such as excessive physical and psychosocial work demands and poor wellbeing. In addition to the factors such as financial, social issues, work related elements and health has a pronounced effect towards early retirement. The most important way for organizations to extend working lives is to look after the health of their employees. Giving the workers an increased sense of control and lowering job demands helps to prevent early retirement. Supporting employees in their working period need to be gradually reviewed and studied taking into account the inflation rate especially during the COVID-19 pandemic

Molecular markers of resistance to amodiaquine plus sulfadoxine-pyrimethamine in an area with seasonal malaria chemoprevention in south central Niger.

BACKGROUND: In Niger, malaria transmission is markedly seasonal with most of the disease burden occurring in children during the rainy season. Seasonal malaria chemoprevention (SMC) with amodiaquine plus sulfadoxine-pyrimethamine (AQ + SP) is recommended in the country to be administered monthly just before and during the rainy season. Moreover, clinical decisions on use of SP for intermittent preventive treatment in pregnancy (IPTp) now depend upon the validated molecular markers for SP resistance in Plasmodium falciparum observed in the local parasite population. However, little is known about molecular markers of resistance for either SP or AQ in the south of Niger. To address this question, clinical samples which met clinical and biological criteria, were collected in Gabi, Madarounfa district, Maradi region, Niger in 2011-2012 (before SMC implementation). Molecular markers of resistance to pyrimethamine (pfdhfr), sulfadoxine (pfdhps) and amodiaquine (pfmdr1) were assessed by DNA sequencing. RESULTS: Prior to SMC implementation, the samples showed a high proportion of clinical samples that carried the pfdhfr 51I/59R/108N haplotype associated with resistance to pyrimethamine and pfdhps 436A/F/H and 437G mutations associated with reduced susceptibility to sulfadoxine. In contrast mutations in codons 581G, and 613S in the pfdhps gene, and in pfmdr1, 86Y, 184Y, 1042D and 1246Y associated with resistance to amodiaquine, were less frequently observed. Importantly, pfdhfr I164L and pfdhps K540E mutations shown to be the most clinically relevant markers for high level clinical resistance to SP were not detected in Gabi. CONCLUSIONS: Although parasites with genotypes associated with the highest levels of resistance to AQ + SP are not yet common in this setting, their importance for deployment of SMC and IPTp dictates that monitoring of these markers of resistance should accompany these interventions. This study also highlights the parasite heterogeneity within a small spatial area and the need to use caution when extrapolating results from surveys of molecular markers of resistance in a single site to inform regional policy decisions

CP-odd observables in neutralino production with transverse e+ and e- beam polarization

We consider neutralino production and decay e^+e^ --> chi^0_i chi^0_j, chi^0_j --> chi^0_1 f \bar{f} at a linear collider with transverse e^+ and e^- beam polarization. We propose CP asymmetries by means of the azimuthal distribution of the produced neutralinos and of that of the final leptons, while taking also into account the subsequent decays of the neutralinos. We include the complete spin correlations between production and decay. Our framework is the Minimal Supersymmetric Standard Model with complex parameters. In a numerical study we show that there are good prospects to observe these CP asymmetries at the International Linear Collider and estimate the accuracy expected for the determination of the phases in the neutralino sector.Comment: 30 pages, minor changes in the introduction, references adde