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Mekonnen Sorsa,1 Gezahegne Mamo,2 Hika Waktole,2 Fufa Abunna,2 Aboma Zewude,3 Gobena Ameni4 1Department of Veterinary Laboratory Technology, School of Veterinary Medicine, Ambo University, Ambo, Oromia, Ethiopia; 2Department of Microbiology, Immunology and Veterinary Public Health, College of Veterinary Medicine and Agriculture, Addis Ababa University, Bishoftu, Oromia, Ethiopia; 3Ethiopian Public Health Institute, Addis Ababa, Ethiopia; 4Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, EthiopiaCorrespondence: Mekonnen SorsaDepartment of Veterinary Laboratory Technology, School of Veterinary Medicine, Ambo University, P.O. Box 19, Ambo, Oromia, Ethiopia, Tel +251 911744881, Email sorsa.mekonnen@yahoo.comBackground: Brucellosis is a zoonotic disease with economic and public health significance in developing countries that rely on livestock production including Ethiopia. This study intended to establish the seroprevalence and associated risk factors of ovine brucellosis.Methods: A cross-sectional study was carried out on seroepidemiology of ovine brucellosis from January 2017 to June 2020 G.C in five districts of South Omo zone, Southern Ethiopia. A total of 1536 sera samples were collected from sheep and serially tested using modified Rose Bengal plate test, competitive enzyme-linked immunosorbent assay, and complement fixation test to detect antibodies against natural infection by Brucella species. A structured questionnaire was used to collect data from individual animals, and flocks for the analysis of the association between expounding and outcome variables. Data were analyzed using STATA version 14.0 and potential risk factors for seropositivity of brucellosis were analyzed using logistic regression.Results: The study discovered an overall 5.40% (95% CI: 6.34, 14.25) and 39.74% (95% CI: 6.50, 6.97) seroprevalence of ovine brucellosis at individual and flock level, respectively, by a confirmatory test. Age groups, sex, flock size, district, history of abortion, and body condition were significantly associated risk factors with Brucella seropositivity (p < 0.05).Conclusion: To conclude, the prevalence of ovine brucellosis in the South Omo Zone was relatively high which needs integrated intervention approaches in place to curb the spread of the disease.Keywords: brucellosis, Ethiopia, ovine, seroprevalence, South Omo

Erdaw Tachbele,1,2 Samuel Kyobe,3 Fred Ashaba Katabazi,3 Edgar Kigozi,3 Savannah Mwesigwa,3 Moses Joloba,3 Alebachew Messele,1 Wondwossen Amogne,2 Mengistu Legesse,1 Rembert Pieper,4 Gobena Ameni1 1Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia; 2College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia; 3College of Health Sciences, Makerere University, Kampala, Uganda; 4Janssen Biopharma, South San Francisco, CA, USACorrespondence: Erdaw Tachbele Tel +251 911642880Email erdawt@yahoo.comPurpose: This study was conducted to investigate the drug resistance mutations and genetic diversity of HIV-1 in ART experienced patients in South Omo, Ethiopia.Patients and Methods: A cross-sectional study conducted on 253 adult patients attending ART clinics for ≥ 6 months in South Omo. Samples with VL ≥ 1000 copies/mL were considered as virological failures (VF) and their reverse transcriptase gene codons 90– 234 were sequenced using Illumina MiSeq. MinVar was used for the identification of the subtypes and drug resistance mutations. Phylogenetic tree was constructed by neighbor-joining method using the maximum likelihood model.Results: The median duration of ART was 51 months and 18.6% (47/253) of the patients exhibited VF. Of 47 viraemic patients, the genome of 41 were sequenced and subtype C was dominant (87.8%) followed by recombinant subtype BC (4.9%), M-09-CPX (4.9) and BF1 (2.4%). Of 41 genotyped subjects, 85.4% (35/41) had at least one ADR mutation. Eighty-one percent (33/41) of viraemic patients harbored NRTI resistance mutations, and 48.8% (20/41) were positive for NNRTI resistance mutations, with 43.9% dual resistance mutations. Among NRTI resistance mutations, M184V (73.2%), K219Q (63.4%) and T215 (56.1%) complex were the most mutated positions, while the most common NNRTI resistance mutations were K103N (24.4%), K101E, P225H and V108I 7.5% each. Active tuberculosis (aOR=13, 95% CI= 3.46– 29.69), immunological failure (aOR=3.61, 95% CI=1.26– 10.39), opportunistic infections (aOR=8.39, 95% CI= 1.75– 40.19), and poor adherence were significantly associated with virological failure, while rural residence (aOR 2.37; 95% CI: 1.62– 9.10, P= 0.05), immunological failures (aOR 2.37; 95% CI: 1.62– 9.10, P= 0.05) and high viral load (aOR 16; 95% CI: 5.35 51.59, P < 0.001) were predictors of ADR mutation among the ART experienced and viraemic study subjects.Conclusion: The study revealed considerable prevalence of VF and ADR mutation with the associated risk indicators. Regular virological monitoring and drug resistance genotyping methods should be implemented for better ART treatment outcomes of the nation.Keywords: HIV-1, genetic diversity, acquired drug resistance, ART experienced, South Omo, Ethiopia

Bedru Hussien,1 Gobena Ameni2– 4 1Department of Public Health, Madda Walabu University, Goba Referral Hospital, Robe Bale, Oromia, Ethiopia; 2Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia; 3Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates; 4Department of Health Studies, University of South Africa, Pretoria, South AfricaCorrespondence: Bedru Hussien Tel +251911997287Email bedruplos1964@gmail.comPurpose: To estimate the magnitude of undernutrition in tuberculosis (TB) patients and evaluate its association with selected sociodemographic and clinical characteristics of the patients.Patients and Methods: A health facility-based cross-sectional design was used. Four hundred and fifty pulmonary TB (PTB) patients were recruited between September 2017 and August 2018. Data were collected by structured questionnaire and anthropometric measurements. Data were analyzed using SPSS 20. Descriptive statistics was used for the analysis and expression of the data. Regression model was used to determine the association between undernutrition and selected factors.Results: The magnitude of underweight was 51.6%, (95%CI: 47.15– 56.2). Binary logistic regression indicated that previous treatment with anti-TB (crude odds ratio, COR=1.68, 95%CI: 1.08– 2.63; p< 0.023), duration of illness greater than two months (COR=2.11, 95%CI: 1.26– 3.55, p< 0.005), positive HIV serum status (COR=3.83, 95%CI: 1.63– 9.02, p< 0.002) and history of resistance to any anti TB drug (COR=2.76, 95%CI: 1.29– 5.91, p< 0.009) were associated with underweight. Multiple logistic regression analysis of the association of the aforementioned variables with undernutrition indicated that HIV positivity (adjusted odds ratio, AOR=0.26, 95%CI: 0.104– 0.65, p< 0.004) and resistance to any anti-TB drug (AOR=0.39, 95%CI: 0.173– 0.90, p< 0.026) were the associated factors.Conclusion: A significant proportion of TB patients in the Oromia Region were malnourished. Therefore, nutritional counseling and nutritional supplementation are required for the effective treatment of TB patients in the Region.Keywords: body mass index, undernutrition, tuberculosis, Oromia Region of Ethiopia

Biniam Wondale,1,2 Girmay Medhin,1 Gemeda Abebe,3 Samuel Tolosa,1 Temesgen Mohammed,1 Takele Teklu,1,4 Rembert Pieper,5 Gobena Ameni1 1Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia; 2Department of Biology, Arba Minch University, Arba Minch, Ethiopia; 3Mycobacteriology Research Center, Jimma University, Jimma, Ethiopia; 4Department of Immunology and Molecular Biology, University of Gondar, Gondar, Ethiopia; 5J. Craig Venter Institute, Rockville, MD, USA Background: Knowledge of drug-sensitivity patterns of Mycobacterium tuberculosis complex (MTBC) strains isolated from patients is an important aspect of TB control strategy. This study was conducted to evaluate the drug sensitivity of MTBC isolates in South Omo, southern Ethiopia.Materials and methods: A total of 161 MTBC isolates (153 from new cases and eight re-treatment TB cases) were isolated using Lowenstein Jensen medium of which 126 isolates were able to be tested for drug sensitivity by BACTECTMMGITTM 960 system, while all the 161 isolates were tested by GenoType® MTBDRplus VER 2.0. Descriptive statistics and logistic regression were used to express and present results.Results: On the basis of MGIT 960 system, the prevalence of mono-resistance was 9.2% (11/119) in the new cases, although neither poly-resistance nor multidrug resistance (MDR) was recorded in these cases. On the basis of GenoType MTBDRplus assay, two of the 153 isolates (1.3%) of the new cases were mono-resistant for rifampicin (RIF) and one of these isolates had known rpoB gene mutation (H526D). One of the eight (12.5%) isolates obtained from the re-treatment cases was MDR with rpoB gene mutation (D516V) and katG gene mutation (S315T2). Taking MGIT 960 system as a gold standard, the sensitivities of the MTBDRplus assay were 33.3%, 100% and 100% for detection of resistance to isoniazid, RIF and MDR, respectively. On the other hand, its specificities were 99.2%, 100% and 100% for detection of resistance to RIF, isoniazid and MDR, respectively.Conclusion: The magnitude of drug resistance was relatively low in the new TB cases of South Omo as compared to the reports from the other regions of the country. This is encouraging and hence the TB Control Program in the Zone should strengthen its program so that the emergence of drug resistance is inhibited. Keywords: drug resistance, MTBDRplus, MGIT 960

In this study, the influence of different additives on a geopolymer matrix composite (GMC) was explored as an alternative to a ceramic matrix composite (CMC) for thermostructural applications. Different GMCs using an N610 textile (10 × 10 cm2) and various additives (SrCO3, BaCO3, BaSO4, MgO and Al2O3 and mullite-rich powder) were cured under 6 MPa at 120 °C for 2 h. The mechanical, microstructural and structural data of the composites were compared with those of the geopolymer matrix after thermal treatment at 1150 °C. The results showed that the addition of alkali-earth barium carbonate or sulfate to the geopolymer matrix facilitated the formation of alkali-earth aluminosilicate crystalline phases and a higher viscous flow apparition temperature (990 °C), which did not enhance its mechanical properties (50 MPa) due to poor impregnation of the textile. Refractory additives such as MgO and Al2O3 in the geopolymer matrix support fiber impregnation with a low-viscous-flow apparition temperature (865 °C) and the formation of crystalline phases such as forsterite, spinel and sapphirine, which act as reinforcements, allowing a flexural strength up to 80 MPa. The addition of a refractory compound, such as mullite, leads to better embedding of fibers and a flexural strength reaching 100 MPa. To conclude, mixing the geopolymer matrix with refractory compounds results in a successful thermo-structural geopolymer composite.

This paper presents three novel encryption and decryption schemes based on graph theory that aim to improve security and error resistance in communication networks. The novelty of this work lies in the application of complete bipartite graphs in two of the schemes and the Cartesian product of graphs in the third, representing a unique approach to cryptographic algorithm development. Unlike traditional cryptographic methods, these graph-based schemes use structural properties of graphs to achieve robust encryption, providing greater resistance to attacks and corruption. Each scheme is illustrated with detailed examples that show how the algorithms can be successfully implemented. The algorithms are written in standard mathematical notation, making them adaptable for machine implementation and scalable for real-world use. The schemes are also rigorously analyzed and compared in terms of their temporal and spatial complexities, using Big O notation. This comprehensive evaluation focuses on their effectiveness, providing valuable insights into their potential for secure communication in modern networks.

This analysis emphasizes the significance of radiation and chemical reaction effects on the boundary layer flow (BLF) of Casson liquid over a linearly elongating surface, as well as the properties of momentum, entropy production, species, and thermal dispersion. The mass diffusion coefficient and temperature-dependent models of thermal conductivity and species are used to provide thermal transportation. Nonlinear partial differential equations (NPDEs) that go against the conservation laws of mass, momentum, heat, and species transportation are the form arising problems take on. A set of coupled dimensionless partial differential equations (PDEs) are obtained from a set of convective differential equations by applying the proper non-similar transformations. Local non-similarity approaches provide an analytical approximation of the dimensionless non-similar system up to two degrees of truncations. The built-in Matlab (Version: 7.10.0.499 (R2010a)) solver bvp4c is used to perform numerical simulations of the local non-similar (LNS) truncations.

This paper aims to investigate new coincidence point theorems for self-maps under an extended rational contraction. Our approach uses the p-adic distance in partially ordered ultrametric spaces. Furthermore, to illustrate our major discoveries, we give a comprehensive numerical analysis. This study expands on prior research in partially ordered ultrametric spaces to provide a more comprehensive understanding of such spaces using rational contraction.

Nanostar dendrimers are tree-like nanostructures with a well-defined, symmetrical architecture. They are built in a step-by-step, controlled synthesis process, with each layer or generation building on the previous one. Dendrimers are made up of a central core, a series of repeating units or branches, and a surface group shell. A weighted graph is a type of graph in which vertices or edges are assigned weights that represent cost, distance, and a variety of other relative measuring units. The weighted graphs have many applications and properties in a mathematical context. The topological indices are numerical values that represent the symmetry of a molecular structure. They have rich applications in theoretical chemistry. Various topological indices can be used to investigate a wide range of properties of chemical compounds with a molecular structure. They are very important in mathematical chemistry, especially in quantitative structure-activity relationship (QSAR) and quantitative structure-property relationship (QSPR) studies. In this paper, we examine the topological properties of the molecular graphs of nanostar dendrimers. For this purpose, the topological indices, namely, the Wiener index and the Wiener polarity index are computed for a class of nanostar dendrimers.

In this study, we use the Hilfer derivative to analyze the approximate controllability of fractional stochastic evolution inclusions (FSEIs) with nonlocal conditions. By assuming that the corresponding linear system is approximately controllable, we obtain a novel set of adequate requirements for the approximate controllability of nonlinear FSEIs in meticulous detail. The fixed-point theorem for multi-valued operators and fractional calculus are used to achieve the results. Finally, we use several instances to demonstrate our findings.

This research looks at the incompressible, viscous, steady-state laminar stagnation-point-flow of a Carreau ternary-hybrid nano-liquid towards a convectively heated expanding surface, taking into account first-order slippage and Ohmic dissipation. Viscous dissipation and the effects of Lorentz forces are also considered. It is discussed how thermal radiation and heat absorption/generation contribute to the heat transport process. Minimizing entropy during the transport of a Carreau ternary hybrid nano-liquid has also been studied. In addition, convective circumstances are used conceptually in the numerical solution of the current model. tiny-particles of silver (Ag), molybdenum disulfide (MoS2), and multi-wall carbon nanotubes (MWCNT) are analyzed in this work’s flow study. As a base fluid, carboxymethyl cellulose (CMC-water) is used. With the use of appropriate similarity trans-formations, the standard model equations are transformed into dimensionless form. Finding solutions for momentum and heat fields using the Runge–Kutta-Fehlberg technique and a shooting strategy. The figures depict a wide range of characteristics, including fluid flow velocity, temperature, skin friction, the Nusselt number, entropy minimization, and the Bejan number. Key results from the present model include the fact that the velocity curve flattens down as Weissenberg number increases.

The objective of this work is to study the effect of the nature (potassium or a mixture of potassium and sodium) and concentration of alkali cations on the behavior of geopolymers at a high temperature (1150 °C). First, the physico-chemical characteristics of the different geopolymers, such as the initial viscosity, the density of the mixture and structural data (Raman spectroscopy), are presented. Then, thermal analysis, dilatometry and mercury porosity are conducted, as well as the mechanical behavior and X-ray diffraction after 1150 °C. The different formulations display different trends depending on the concentration and the nature of the alkaline cations. In comparison to the use of a potassium cation, the addition of sodium leads to an increase of the viscosity and a decrease of the onset temperature of the viscous flow. The potassium-based formulations show better behavior after treatment at high temperature (1150 °C). The improvement in the mechanical properties after thermal treatment is controlled by the different crystalline phases formed, such as leucite and anorthite.

A novel series of 1,2,3-triazole-benzimidazolidinone hybrid derivatives were designed and synthesized via click reaction, between various aryl azide and a terminal alkyne bearing a benzimidazolidinone moiety. All newly synthesized compounds, were efficiently characterized using 1H NMR, 13C NMR and HRMS. Furthermore, the structure of one precursor 5b was supported by single crystal X-ray diffraction. All synthesized derivatives have been evaluated for their antimicrobial and anti-inflammatory activities. Biological activity tests exhibited that the target structures demonstrate that compounds 5a, 5b and 5f have a high antibacterial activity especially derivative 5b. Besides, the in vitro antifungal results revealed that the strongest inhibition recorded to compound 5b in comparison to other products against A. brasiliensis, A. fumigatus and C. albicans. Biological activity evaluation indicated that the synthesized compounds possess moderate anti-inflammatory effects. The most effective compound in terms of efficacy and potency was 5a. Molecular docking simulation was used to investigate the most active compounds' probable binding mechanisms in order to provide a plausible explanation for their biological activity.

Summary: Bovine tuberculosis (bTB) is highly prevalent in intensive dairy farms of the urban “milk‐sheds” in Ethiopia, and vaccination could be a cost‐effective disease control strategy. In the present study, the efficacy of Bacillus Calmette–Guerin (BCG) to protect against bTB was assessed in Holstein–Friesian calves in a natural transmission setting. Twenty‐three 2‐week‐old calves were subcutaneously vaccinated with BCG Danish SSI strain 1331, and matched 26 calves were injected with placebo. Six weeks later, calves were introduced into a herd of M. bovis‐infected animals (reactors) and kept in contact with them for 1 year. In vitro and in vivo immunological tests were performed to assess immune responses post‐vaccination and during exposure. Successful vaccine uptake was confirmed by tuberculin skin test and IFN‐γ responses in vaccinated calves. The kinetics of IFN‐γ responses to early secretory antigen target 6 and culture filtrate protein 10 (ESAT6 and CFP10, respectively) and tuberculin skin test responses post‐exposure suggested that the animals were infected early after being placed in contact with the infected herd as immunological signs of infection were measurable between 2 and 4 months post‐initial exposure. Protection was determined by comparing gross and microscopic pathology and bacteriological burden between vaccinated and control calves. BCG vaccination reduced the proportions of tissues with visible pathology in vaccinates compared to control calves by 49% (p < .001) with 56%, 43%, 72%, and 38% reductions in the proportion of lesioned tisues in head, thoracic, abdominal lymph nodes, and lungs, respectively (p‐values .029–.0001). In addition, the lesions were less severe grossly and microscopically in vaccinated calves than in non‐vaccinated calves (p < .05). The reduction in the overall incidence rates of bTB was 23%, 28%, and 33% on the basis of the absence of gross pathology, M. bovis culture positivity, and histopathology, respectively, in vaccinated animals. In conclusion, BCG vaccination reduced the frequency and severity of the pathology of bTB significantly, which is likely to reduce onwards transmission of the disease. [ABSTRACT FROM AUTHOR]

The generalized Petersen graphs are a type of cubic graph formed by connecting the vertices of a regular polygon to the corresponding vertices of a star polygon. This graph has many interesting graph properties. As a result, it has been widely researched. In this work, the edge metric dimensions of the generalized Petersen graphs GP(2l + 1, l) and GP(2l, l) are explored, and it is shown that the edge metric dimension of GP(2l + 1, l) is equal to its metric dimension. Furthermore, it is proved that the upper bound of the edge metric dimension is the same as the value of the metric dimension for the graph GP(2l, l).

Circulant networks are a very important and widely studied class of graphs due to their interesting and diverse applications in networking, facility location problems, and their symmetric properties. The structure of the graph ensures that it is symmetric about any line that cuts the graph into two equal parts. Due to this symmetric behavior, the resolvability of these graph becomes interning. Subdividing an edge means inserting a new vertex on the edge that divides it into two edges. The subdivision graph G is a graph formed by a series of edge subdivisions. In a graph, a resolving set is a set that uniquely identifies each vertex of the graph by its distance from the other vertices. A metric basis is a resolving set of minimum cardinality, and the number of elements in the metric basis is referred to as the metric dimension. This paper determines the minimum resolving set for the graphs Hl[1,k] constructed from the circulant graph Cl[1,k] by subdividing its edges. We also proved that, for k=2,3, this graph class has a constant metric dimension.

Geopolymers can be optimized to have interesting physical characteristics, which are influenced by the raw materials and additives utilized in their formulations. For this reason, various formulations of two metakaolin-based binders with filler additions of different natures, i.e., sands and carbonates, were tested. The aluminosilicate source used is a commercial metakaolin (Si/Al = 1.44). The feasibility of the consolidated samples and their thermal behaviors were evaluated. The viscosity tests of the fresh geopolymer pastes indicated that their setting times are controlled by their potassium concentrations. The evaluation of the thermal stabilities of consolidated samples was carried out before and after heat treatment at 1000 °C by means of compressive tests. Geopolymers with low potassium concentrations showed mechanical strengths that were 16% greater (37–43 MPa) than geopolymers with high potassium concentrations, both before and after heat treatment. The exposure to different conditions did not influence the final mechanical properties of the geopolymers. XRD analysis of the geopolymers was performed and the crystallization of kalsilite was found in samples high potassium concentrations. Different mechanisms during geopolymerization, specifically the kinetic and thermodynamic mechanisms of geopolymers with high and low potassium concentrations, respectively, can explain the diverse mechanical responses of the geopolymers at room temperature, while the presence of kalsilite can explain the differences of geopolymers at high temperatures. Hence, it is possible to develop fire-resistant geopolymers by controlling the concentrations of potassium and fillers.

Differential diagnosis of tuberculosis (TB) and latent TB infection (LTBI) remains a public health priority in high TB burden countries. Pulmonary TB is diagnosed by sputum smear microscopy, chest X-rays, and PCR tests for distinct Mycobacterium tuberculosis (Mtb) genes. Clinical tests to diagnose LTBI rely on immune cell stimulation in blood plasma with TB-specific antigens followed by measurements of interferon-γ concentrations. The latter is an important cytokine for cellular immune responses against Mtb in infected lung tissues. Sputum smear microscopy and chest X-rays are not sufficiently sensitive while both PCR and interferon-γ release assays are expensive. Alternative biomarkers for the development of diagnostic tests to discern TB disease states are desirable. This study’s objective was to discover sputum diagnostic biomarker candidates from the analysis of samples from 161 human subjects including TB patients, individuals with LTBI, negative community controls (NCC) from the province South Omo, a pastoral region in Ethiopia. We analyzed 16S rRNA gene-based bacterial taxonomies and proteomic profiles. The sputum microbiota did not reveal statistically significant differences in α-diversity comparing the cohorts. The genus Mycobacterium, representing Mtb, was only identified for the TB group which also featured reduced abundance of the genus Rothia in comparison with the LTBI and NCC groups. Rothia is a respiratory tract commensal and may be sensitive to the inflammatory milieu generated by infection with Mtb. Proteomic data supported innate immune responses against the pathogen in subjects with pulmonary TB. Ferritin, an iron storage protein released by damaged host cells, was markedly increased in abundance in TB sputum compared to the LTBI and NCC groups, along with the α-1-acid glycoproteins ORM1 and ORM2. These proteins are acute phase reactants and inhibit excessive neutrophil activation. Proteomic data highlight the effector roles of neutrophils in the anti-Mtb response which was not observed for LTBI cases. Less abundant in the sputum of the LTBI group, compared to the NCC group, were two immunomodulatory proteins, mitochondrial TSPO and the extracellular ribonuclease T2. If validated, these proteins are of interest as new biomarkers for diagnosis of LTBI.

This study aims to explore geopolymer binders and mortars based on local Moroccan clays and sands as coatings for the restoration of historical monuments in Morocco. For this, five substrates, one geopolymer binder, and two geopolymer mortars were investigated. The characterization of substrates reveals differences in terms of pH value, capillarity, contact angle, and surface roughness. These differences affect the coating thickness, which also depends on the viscosity, liquid to solid ratio, and granular skeleton of the geopolymer coating. High adhesive strength values (up to 9 MPa) were obtained on limestones. However, these values decreased with the increase of relative humidity. In the case of Fez stone, a stable adhesive strength value (3 MPa) was evidenced for all the coating formulations and at different storage conditions confirming the suitability of coating based on metakaolin, Moroccan clays, and sands for restoration applications.