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Optimization and statistical methods are used to minimize the number of experiments required to complete a study, especially in corrosion testing. Here, a statistical Box–Behnken design (BBD) was implemented to investigate the effects of four independent variables (inhibitor concentration [I], immersion time t, temperature ϑ, and NaCl content [NaCl]) based on the variation of three levels (lower, middle, and upper) on the corrosion protection efficiency of the green inhibitor oleoylsarcosine for low-carbon steel type CR4 in salt water. The effects of the selected variables were optimized using the response surface methodology (RSM) supported by the Minitab17 program. Depending on the BBD analytical tools, the largest effects were found for ϑ, followed by [I]. The effect of interactions between these variables was in the following order: [I] and ϑ > t and ϑ > [I] and [NaCl]. The second-order model used here for optimization showed that the upper level (+1) with 75 mmol/L for [I], 30 min for t, and 0.2 mol/L [NaCl] provided an optimal protective effect for each of these factors, while the lower level (−1) was 25 °C for ϑ. The theoretical efficiency predicted by the RSM model was 99.4%, while the efficiency during the experimental test procedure with the best-evaluated variables was 97.2%.

To investigate the corrosion protection behavior of naturally derived cocoyl sarcosine in combination with N-b-hydroxyethyl oleyl imidazole for steel CR4 in 0.1 M NaCl, different evaluation systems (weight loss, electrochemical measurements, and spray corrosion tests) were used. Both compounds were tested in different concentrations (25–100 mmol/L) and with variable dip coating times (1–30 min), first individually and then in combination, to check any synergistic effects for surface protection. Both showed only an insignificant corrosion inhibiting effect with less than 50% efficiency at all concentrations and dip coating times if used alone. In contrast, compound combinations revealed an improved corrosion inhibition correlated with higher concentrations. Across all methods, the compound combination concentration of 100 mmol/L resulted in improved efficiency of up to 83% for gravimetric tests, up to 84% for the impedance measure and more than 91% for potentiodynamic polarization. Dip coating variations proved 10 min to be the best option for all compounds with a maximum efficiency of up to 86% for the compound combination.

Omaima Changuiti,1 Nawar Moustarhfir,1 Abdelghafour Marfak,1,2 Elmadani Saad,1 Abderraouf Hilali,1 Ibtissam Youlyouz-Marfak1 1Hassan First University of Settat, Higher Institute of Health Sciences, Laboratory of Health Sciences and Technologies, Settat, 26000, Morocco; 2National School of Public Health, Rabat, 10000, MoroccoCorrespondence: Ibtissam Youlyouz-MarfakHassan First University of Settat, Higher Institute of Health Sciences, Laboratory of Health Sciences and Technologies, Settat, 26000, MoroccoTel +212 6 61 60 43 58Fax +212 5 23 40 01 87Email ibtissam.marfak@uhp.ac.maPurpose: A health professional’s learning curriculum should lead to the acquisition of technical and non-technical skills. This study aims at demonstrating the impact of simulation-based learning (SBL) experience on the learning of midwifery students.Patients and Methods: Using an experimental design, the experimental group (n=14) received pretest, high fidelity simulation, then a post-test. Whereas the control group (n=14) received pretest, revision of the theoretical course instead of simulation, post-test 1, high fidelity simulation, then a post-test 2. The first scenario was about a normal childbirth when the midwifery students were in their 2nd year. And then the second one was about immediate postpartum hemorrhage when the students moved to their 3rd year.Results: During the simulation sessions, the experimental group had a higher mean score in the post-test than the control group. This indicated that the simulation significantly (p< 0.001) increased the students’ knowledge. Also, for both eutocic and dystocic delivery simulation experiments, students obtained higher score in the second simulation sessions (19.69 and 19.4 for eutocic and dystocic, respectively) than in the first session (11.23 and 9.12 for eutocic and dystocic, respectively; p< 0.0001).Conclusion: These findings confirm that SBL offers an opportunity for learners to be immersed in an environment that is closer to reality, thus improving learning in a safe environment.Keywords: postpartum hemorrhage, midwifery, high fidelity simulation, training, curriculum, obstetric

Pathogen-based factors associated with tuberculosis (TB) in eastern Sudan are not well defined. We investigated genetic diversity, drug resistance, and possible transmission clusters of Mycobacterium tuberculosis complex (MTBC) strains by using a genomic epidemiology approach. We collected 383 sputum specimens at 3 hospitals in 2014 and 2016 from patients with symptoms suggestive of TB; of these, 171 grew MTBC strains. Whole-genome sequencing could be performed on 166 MTBC strains; phylogenetic classification revealed that most (73.4%; n = 122) belonged to lineage 3 (L3). Genome-based cluster analysis showed that 76 strains (45.9%) were grouped into 29 molecular clusters, comprising 2–8 strains/patients. Of the strains investigated, 9.0% (15/166) were multidrug resistant (MDR); 10 MDR MTBC strains were linked to 1 large MDR transmission network. Our findings indicate that L3 strains are the main causative agent of TB in eastern Sudan; MDR TB is caused mainly by transmission of MDR L3 strains.

تم تحضير معقدات جديدة للنحاس تتضمن ليكندات مختلطة صيغتها العامة [Cu(4-Hydrpipdtc)2L2] و [Cu(4-methylpipdtc)2L2] حيث ان (4-Hydrpipdtc), و(4-methylpipdtc) = 4-hydroxylpiperidinedithiocarbamate و 4-methylpiperidinedithiocarbamate على التوالي و L = 4-picoline ,luitidine ,en ,(1-10)phen,PPh3وشخصت المعقدات المحضرة بواسطة تحليل العناصر وقياسات التوصيلية واطياف الاشعة تحت الحمراء والمرئية والفوق البنفسجية وقياسات الحساسية المغناطيسية ومن النتائج تم اقتراح الشكل المربع المستوي للمعقد بس داي ثايوكاربميت نحاس (II) والشكل ثماني السطوح للمعقدات الاخرى.

Tuberculosis (TB) is a chronic bacterial disease of humans and animals. It is characterized by the progressive development of specific granulomatous lesions in affected organs. Human TB is endemic in Eastern Sudan. However, knowledge on the epidemiology of TB in ruminants is scarce. In a six-month study from June to November 2014, a total of 2304 carcasses of cattle, sheep, goats and camels slaughtered at the East and West Gaash slaughterhouses of Kassala were inspected to investigate TB prevalence. Only 0.1% (n = 2) of the carcasses had suspicious TB lesions. These lesions were solely found in carcasses of sheep, in the liver, lungs, and peritoneal cavity. The samples collected from the lesions were investigated for the presence of mycobacteria, which were found in one of the two carcasses. The grown bacteria were subjected to a line probe assay (GenoType Mycobacterium CM), and to 16S rDNA and ITS gene sequencing, and whole genome sequencing (WGS). However, none of these methods identified this isolate as a valid Mycobacterium species. Nevertheless, 16S sequence allocated this isolate to slow growing mycobacteria. Neither Mycobacterium bovis nor M. caprae nor M. tuberculosis were found in the collected granulomatous lesions. In conclusion, the overall prevalence of TB-suggestive lesions in ruminants in Kassala was very low. Extended studies combining the use of a tuberculin skin test and slaughterhouse-based investigations should be adopted for TB surveillance in ruminants in Sudan.

Background. In Sudan, tuberculosis diagnosis largely relies on clinical symptoms and smear microscopy as in many other low- and middle-income countries. The aim of this study was to investigate the positive predictive value of a positive sputum smear in patients investigated for pulmonary tuberculosis in Eastern Sudan. Methods. Two sputum samples from patients presenting with symptoms suggestive of tuberculosis were investigated using direct Ziehl-Neelsen (ZN) staining and light microscopy between June to October 2014 and January to July 2016. If one of the samples was smear positive, both samples were pooled, stored at −20°C, and sent to the National Reference Laboratory (NRL), Germany. Following decontamination, samples underwent repeat microscopy and culture. Culture negative/contaminated samples were investigated using polymerase chain reaction (PCR). Results. A total of 383 samples were investigated. Repeat microscopy categorized 123 (32.1%) as negative, among which 31 were culture positive. This increased to 80 when PCR and culture results were considered together. A total of 196 samples were culture positive, of which 171 (87.3%), 14 (7.1%), and 11 (5.6%) were M. tuberculosis, M. intracellulare, and mixed species. Overall, 15.6% (57/365) of the samples had no evidence of M. tuberculosis, resulting in a positive predictive value of 84.4%. Conclusions. There was a discordance between the results of smear microscopy performed at local laboratories in the Sudan and at the NRL, Germany; besides, a considerable number of samples had no evidence of M. tuberculosis. Improved quality control for smear microscopy and more specific diagnostics are crucial to avoid possible overtreatment.

In this paper, we elaborated the nickel-based alloy type Hastelloy G30 and we analyzed it by techniques of characterization in order to interpret the results obtained through a computer simulation. The calculation of the thermo-physical properties of the alloy and the simulation of filling and solidification of the casting was performed by the software ProCAST. The validation of the numerical results was done by the following experimental techniques: optical microscopy and hardness test. In the center of the elaborate piece, the experimental results showed the appearance of porosity and leading to embrittlement of the alloy. According to the numerical simulation, this is caused by a fraction of the liquid that remains trapped in this area.

The Box-Behnken Design (BBD) is used to model the sacrificial Cathodic Protection System (SCPS) to find the factors effectiveness behaviour. For protection potential assessment the BBD receives (resistivity of environment, sacrificial anode alloy, distance between anode and cathode and surface area for the structure to be protected) as input and gives the protection potential as output. By applying BBD with their analysis tools we get many results. The important results which are the factors individual effectiveness on the sacrificial cathodic protection (SCP) process are the resistivity which has the greatest effect on the potential protection (rank=1) followed by sacrificial anode alloy type (rank=2), surface area for structure protected required (rank=3) and distance between anode and cathode (rank=4). The interaction of sacrificial anode alloy and cathode area (χ2χ4) has significant effect on CP process with the limits which are used in this work while the other factors interaction (χ1χ2, χ1χ3, χ1χ4,χ2χ3, χ3χ4) has insignificant effect on the limits which used in this work.

Translating linguistic terms has taken little concern from translation researchers and scholars. This research paper discusses the attempts made by senior students of the English department, University of Benghazi, at EL-Marj Campus when they translate linguistic terms (or names of their department courses). In order to examine their translations, the researcher hypothesizes that if English undergraduate students at Benghazi University learn certain strategies which they use as tools when translating the list of their courses and they are aware of the equivalence of some of these courses' names, they will not find difficulties in translating these linguistic terms. To check this hypothesis and to achieve the aims of this study, translation test, questionnaire, and semi-structured interview are used as data collection in this study. A qualitative study is used to deal with twenty six senior students from the department of English, in the academic year 2018/2019. The results show that the students use code switching intentionally, as adding local color to when they speak. Others could not know their translation equivalents in the target, Arabic. Accordingly, they apply code switching in order to overcome their translation inability. The findings of the study also revealed that the most frequently used translation strategy is equivalence translation. This study will also be useful everywhere else.

Tuberculosis (TB) remains a major global health problem; 10 million new cases were reported in 2018 (1). In Sudan, the estimated national TB incidence in 2018 was 71/100,000 persons; a [...]

In this paper, the impact of small additions of indium (In), nickel (Ni), and Titanium dioxide nanoparticles (TiO2 NPs) in the microstructure and characterization of eutectic Sn–0.7 Cu (SC07)-based solder were investigated. The third element In, Ni, or TiO2 NPs were added in varying amounts 0.4 or 0.8 wt% to SC07 alloy by replacing an equal amount of Sn for each addition. Structural analysis of the investigated samples showed that the addition of Ni or In modified the eutectic composition, leading to the appearance of primary phases (Cu6Sn5) followed by the formation of intermetallic compounds (IMCs) (Cu, Ni)6Sn5 and Cu6(Sn, In)5. However, addition of TiO2 NPs did not lead to formation of any new IMCs but refine β-Sn dendrites grains with a decrease in the volume fraction of Cu6Sn5 IMC. The crystallite size, lattice strain, and dislocation density of the SC07 solder alloy were improved in terms of third addition. The results indicated that the smallest crystallite size for SC07–0.8In associated with largest lattice strain and highest dislocation density. Microhardness tests were performed for all samples at room temperature. The results illustrate the enhancement indentation creep resistance of SC07 reinforced solder, which inherently correlates to the microstructure refinement and the formation of intermetallic phases (Cu, Ni)6Sn5 and Cu6(Sn, In)5 with higher hardness values. The obtained stress exponent values are in the range 9.26–11.46 for all tested alloys which close to that creep mechanisms associated with dislocation movement such as dislocation creep are predominant. Thus, we conclude that the greatest value of stress exponent for SC07–0.8In (10.9–11.46) at different loads suggested to be more resistant to indentation creep which improves the mechanical strength compared to other solders. [ABSTRACT FROM AUTHOR]

This study introduces a new series of complexes and adducts, denoted by [M(2-PhOEtXant)2.nL], where M represents Mn(II), Fe(II), Co(II), or Ni(II), and the ligand (2-PhOEtXant) is 2-Phenoxyethylxanthate. Varying ligands, including pyridine, piperidine, quinoline, ethylenediamine, and (1,10)-phenanthroline, are explored based on the value of n. Comprehensive characterization, encompassing techniques like ¹H-NMR, 13C-NMR, FTIR, AA, CHN analysis, UV-visible spectroscopy, and magnetic property measurements, is employed. Results indicate an octahedral geometry for these complexes, as revealed by effective magnetic moment measurements and electronic spectra analysis. The compounds exhibit noteworthy antioxidant properties, demonstrated through the DPPH radical scavenging method, highlighting their potential as effective antioxidants. Moreover, the complexes display enhanced antibacterial activity against microbial strains compared to free ligands. This research not only delves into the coordination chemistry of these complexes but also underscores their diverse applications. Combining experimental methods with computational insights using Density Functional Theory (DFT) enhances the understanding of dithiolate transition metal complexes. The alignment of computational and experimental outcomes strengthens the reliability of the findings, laying a robust foundation for interdisciplinary exploration. The identified potential applications in optoelectronics, along with the notable antioxidant and antibacterial activities, position these complexes as promising contenders for advanced technologies and scientific applications. [ABSTRACT FROM AUTHOR]