Search results for: susceptibility to erosion

Authors: Laura Fernanda Pedreros Araque, Sebastian Rivera Pardo

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The massive removal phenomena have been one of the most frequent natural disasters in the world, causing thousands of deaths, victims, damage to homes and diseases. In Pitalito, and Campoalegre department of Huila municipalities - Colombia, disasters have occurred due to various events such as high rainfall, earthquakes; it has caused landslides, floods, among others, affected the economy, the community, and transportation. For this reason, a study was carried out on the area’s most prone to suffer these phenomena to take preventive measures in favor of the protection of the population, the resources of management, and the planning of civil works. For the proposed object, the Mora-Varshon method was used, which allows classifying the degree of susceptibility to landslides in which the areas are found. Also, various factors or parameters were evaluated such as the soil moisture, lithology, slope, seismicity, and rain, each of these indicators were obtained using information from IDEAM, Servicio Geologico Colombiano (SGC) and using geographic information for geoprocessing in the Arcgis software to realize a mapping to indicate the susceptibility to landslides, classifying the areas of the municipalities such as very low, low, medium, moderate, high or very high.

Keywords: geographic information system, landslide, mass removal phenomena, Mora-Varshon method

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Authors: Zi-Han Li, Zi-Jun Sun, Dong-Yuan Chang, Li Zhu, Min Chen, Ming-Hui Zhao

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Aims: A genome-wide association study (GWAS) reported that patients with the rs55703767 minor allele in collagen type IV α3 chain encoding gene COL4A3 showed protection against diabetic kidney disease (DKD) in type 1 diabetes mellitus (T1DM). However, the role of rs55703767 in type 2 DKD has not been elucidated. The aim of the current study was to investigate the association between COL4A3 variant rs55703767 and DKD risk in Chinese patients with type 2 diabetes mellitus (T2DM). Methods: This nested case-control study was performed on 1311 patients who had T2DM for at least 10 years, including 580 with DKD and 731 without DKD. We detected the genotypes of all patients by TaqMan SNP Genotyping Assay and analyzed the association between COL4A3 variant rs55703767 and DKD risk. Results: Genetic analysis revealed that there was no significant difference between T2DM patients with DKD and those without DKD regarding allele or genotype frequencies of rs55703767, and the effect of this variant was not hyperglycemia specific. Conclusion: Our findings suggested that there was no detectable association between the COL4A3 variant rs55703767 and the susceptibility to DKD in the Chinese T2DM population.

Keywords: collagen type IV α3 chain, gene polymorphism, type 2 diabetes, diabetic kidney disease

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Authors: Tayaba Dastgeer, Farhan Rasheed, Muhammad Saeed, Maqsood Ahmad, Zia Ashraf, Abdul Waheed, Muhammad Kamran, Mohsin Khurshid

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Objectives: The study aimed to determine the efficacy of linezolid against clinical isolates of methicillin-resistant staphylococcus aureus (MRSA). Methodology: This cross-sectional study was conducted in the microbiology department of Allama Iqbal Medical College Lahore from August 2017 to September 2019. Isolates were confirmed as MRSA via the presence of the mec-A gene. Confirmed MRSA isolates were processed for susceptibility testing against different antimicrobials, especially linezolid, via the disc diffusion method. Zone sizes were interpreted according to CLSI guidelines. Results: Various types of clinical samples were included in the study; however, the highest frequency of MRSA isolates was found in pus samples, followed by other clinical samples. Among hospitalized patients, most MRSA isolates were obtained from patients in the surgical ward. Of 243 mec-A gene detected isolates, Vancomycin and linezolid showed 100% susceptibility, chloramphenicol showed declining resistance 78 (32.09%), and emerging sensitivity 165 (67.90%) against MRSA. Conclusion: Linezolid is a very efficient drug against MRSA, but the use of this novel drug must be conserved for vancomycin-resistant Staphylococcus aureus or when more resistant pathogens are suspected.

Keywords: MRSA, chloramphenicol, linezolid, nosocomial infections

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Authors: Rui Huang, Thomas Richard, Masood Mostofi

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The lifetime of impregnated diamond bits and their drilling efficiency are in part governed by the bit wear conditions, not only the extent of the diamonds’ wear but also their exposure or protrusion out of the matrix bonding. As much as individual diamonds wear, the bonding matrix does also wear through two-body abrasion (direct matrix-rock contact) and three-body erosion (cuttings trapped in the space between rock and matrix). Although there is some work dedicated to the study of diamond bit wear, there is still a lack of understanding on how matrix erosion and diamond exposure relate to the bit drilling response and drilling efficiency, as well as no literature on the process that governs bit sharpening a procedure commonly implemented by drillers when the extent of diamond polishing yield extremely low rate of penetration. The aim of this research is (i) to derive a correlation between the wear state of the bit and the drilling performance but also (ii) to gain a better understanding of the process associated with tool sharpening. The research effort combines specific drilling experiments and precise mapping of the tool-cutting face (impregnated diamond bits and segments). Bit wear is produced by drilling through a rock sample at a fixed rate of penetration for a given period of time. Before and after each wear test, the bit drilling response and thus efficiency is mapped out using a tailored design experimental protocol. After each drilling test, the bit or segment cutting face is scanned with an optical microscope. The test results show that, under the fixed rate of penetration, diamond exposure increases with drilling distance but at a decreasing rate, up to a threshold exposure that corresponds to the optimum drilling condition for this feed rate. The data further shows that the threshold exposure scale with the rate of penetration up to a point where exposure reaches a maximum beyond which no more matrix can be eroded under normal drilling conditions. The second phase of this research focuses on the wear process referred as bit sharpening. Drillers rely on different approaches (increase feed rate or decrease flow rate) with the aim of tearing worn diamonds away from the bit matrix, wearing out some of the matrix, and thus exposing fresh sharp diamonds and recovering a higher rate of penetration. Although a common procedure, there is no rigorous methodology to sharpen the bit and avoid excessive wear or bit damage. This paper aims to gain some insight into the mechanisms that accompany bit sharpening by carefully tracking diamond fracturing, matrix wear, and erosion and how they relate to drilling parameters recorded while sharpening the tool. The results show that there exist optimal conditions (operating parameters and duration of the procedure) for sharpening that minimize overall bit wear and that the extent of bit sharpening can be monitored in real-time.

Keywords: bit sharpening, diamond exposure, drilling response, impregnated diamond bit, matrix erosion, wear rate

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Authors: Amir Hamed Abd-Elrahman, Mohamed Bessat

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450 fattening cattle and buffaloes aged from 6 to 30 months old were examined clinically to determine patterns of occurrence of hemoparasitic diseases and the efficacy of different anti theilerial drugs. 420 animals examined clinically to determine relation between different outbreak of FMD and LSD in Egypt 2012- 2013 and haemoprotozoal diseases. The clinical pictures of haemoprotozoal diseases are variable, from sever to mild, depending on the endemic situation which governed by frequent previous exposure and tick infestation. B. bigemina is the most common haemoprotozoal diseases in the area of study and the infection rate in a descending manner for B. bigemina, A. marginale and T. annulata were 20%, 9.7% and 6.6% respectively. The species susceptibility of B. bigemina and T. annulata showed a higher incidence in cattle than buffaloes while in A. marginale showed a little difference in cattle and buffaloes susceptibility by 10% and 9.2% respectively. The breed susceptibility of B. bigemina and T. annulata showed a higher incidence in crossbred cattle than native baladi cattle while A. marginale showed a higher incidence in native baladi cattle than crossbred cattle. The maximal infection rates were recorded during summer months. The infection rates of B. bigemina and A. marginale were higher among young animals over 6 months and declined above 2 year old while in T. annulata the infection rates were lower among young animals and increased above 2 year old. The case fatality of T. annulata was higher than A. marginale and B. bigemina. Efficacy of different anti theilerial drugs were studied, cure rate of chlouroquine group and Butalex group were 60% disappearance of schizont in lymph node smear after 9 days and 5 days respectively while cure rate of Oxytetracycline Dihydrate (Alamycine) group 20% with disappearance of schizont in lymph node smear after 14 days. FMD and LSD infection enhancement the occurrence of bovine haemoprotozoal diseases.

Keywords: Babesia bigemina, Anaplasma marginale, Theileria annulata, FMD, LSD, ephemeral fever

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Authors: M. S. Raza, A. Kapil, Sonu Tyagi, H. Gautam, S. Mohapatra, R. Chaudhry, S. Sood, V. Goyal, R. Lodha, V. Sreenivas, B. K. Das

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Background: Acute bacterial meningitis remains the major cause of mortality and morbidity. More than half of the survivors develop the significant lifelong neurological abnormalities. Diagnosis of the hospital acquired acute bacterial meningitis (HAABM) is challenging as it appears either in the post operative patients or patients acquire the organisms from the hospital environment. In both the situations, pathogens are exposed to high dose of antibiotics. Chances of getting multidrug resistance organism are very high. We have performed this experiment to find out the etiological agents of HAABM and its antibiotics susceptibility pattern. Methodology: A perspective study was conducted at the Department of Microbiology, All India Institute of Medical Sciences, New Delhi. From March 2015 to April 2018 total 400 Cerebro spinal fluid samples were collected aseptically. Samples were processed for cell count, Gram staining, and culture. Culture plates were incubated at 37°C for 18-24 hours. Organism grown on blood and MacConkey agar were identified by MALDI-TOF Vitek MS (BioMerieux, France) and antibiotic susceptibility tests were performed by Kirby Bauer disc diffusion method as per CLSI 2015 guideline. Results: Of the 400 CSF samples processed, 43 (10.75%) were culture positive for different bacteria. Out of 43 isolates, the most prevalent Gram-positive organisms were S. aureus 4 (9.30%) followed by E. faecium 3 (6.97%) & CONS 2 (4.65%). Similarly, E. coli 13 (30.23%) was the commonest Gram-negative isolates followed by A. baumannii 12 (27.90%), K. pneumonia 5 (11.62%) and P. aeruginosa 4(9.30%). Most of the antibiotics tested against the Gram-negative isolates were resistance to them. Colistin was most effective followed by Meropenem and Imepenim for all Gram-negative HAABM isolates. Similarly, most of antibiotics tested were susceptible to S. aureus and CONS. However, E. faecium (100%) were only susceptible to vancomycin and teicoplanin. Conclusion: Hospital acquired acute bacterial meningitis (HAABM) is becoming the emerging challenge as most of isolates are showing resistance to commonly used antibiotics. Gram-negative organisms are emerging as the major player of HAABM. Great care needs to be taken especially in tertiary care hospitals. Similarly, antibiotic stewardship should be followed and antibiotic susceptibility test (AST) should be performed regularly to update the antibiotic patter and to prevent from the emergence of resistance. Updated information of the AST will be helpful for the better management of the meningitis patient.

Keywords: CSF, MALDI-TOF, hospital acquired acute bacterial meningitis, AST

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Authors: Mariam Tsitsagi, Ana Berdzenishvili

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Rainfall intensity change is one of the main indicators of climate change. It has a great influence on agriculture as one of the main factors causing soil erosion. Splash and sheet erosion are one of the most prevalence and harmful for agriculture. It is invisible for an eye at first stage, but the process will gradually move to stream cutting erosion. Our study provides the assessment of rainfall erosivity potential with the use of modern research methods in Kakheti region. The region is the major provider of wheat and wine in the country. Kakheti is located in the eastern part of Georgia and characterized quite a variety of natural conditions. The climate is dry subtropical. For assessment of the exact rate of rainfall erosion potential several year data of rainfall with short intervals are needed. Unfortunately, from 250 active metro stations running during the Soviet period only 55 of them are active now and 5 stations in Kakheti region respectively. Since 1936 we had data on rainfall intensity in this region, and rainfall erosive potential is assessed, in some old papers, but since 1990 we have no data about this factor, which in turn is a necessary parameter for determining the rainfall erosivity potential. On the other hand, researchers and local communities suppose that rainfall intensity has been changing and the number of haily days has also been increasing. However, finding a method that will allow us to determine rainfall erosivity potential as accurate as possible in Kakheti region is very important. The study period was divided into three sections: 1936-1963; 1963-1990 and 1990-2015. Rainfall erosivity potential was determined by the scientific literature and old meteorological stations’ data for the first two periods. And it is known that in eastern Georgia, at the boundary between steppe and forest zones, rainfall erosivity in 1963-1990 was 20-75% higher than that in 1936-1963. As for the third period (1990-2015), for which we do not have data of rainfall intensity. There are a variety of studies, where alternative ways of calculating the rainfall erosivity potential based on lack of data are discussed e.g.based on daily rainfall data, average annual rainfall data and the elevation of the area, etc. It should be noted that these methods give us a totally different results in case of different climatic conditions and sometimes huge errors in some cases. Three of the most common methods were selected for our research. Each of them was tested for the first two sections of the study period. According to the outcomes more suitable method for regional climatic conditions was selected, and after that, we determined rainfall erosivity potential for the third section of our study period with use of the most successful method. Outcome data like attribute tables and graphs was specially linked to the database of Kakheti, and appropriate thematic maps were created. The results allowed us to analyze the rainfall erosivity potential changes from 1936 to the present and make the future prospect. We have successfully implemented a method which can also be use for some another region of Georgia.

Keywords: erosivity potential, Georgia, GIS, Kakheti, rainfall

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Authors: Nasrin Amirrajab, Yasaman Razavi Ghahfarokhi, Zahra Tootak, Maryam Hadian, Fatemeh Abooali Shamshiri

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Urinary tract infections (UTIs) have been reported in children with nephrotic syndrome. However, the only causes for the infection reported to date are bacteria, but not many prior reported occurrences of fungi or yeast as causative organisms. Hence, the present study aimed to describe the epidemiology of urinary tract fungal infections in a tertiary care pediatric. A single-center cross-sectional study was conducted at the nephrology ward of Aboozar Pediatric Hospital between March 21, 2021, and April 28, 2022. Urine was collected aseptically from children, inoculated onto culture media, and incubated at 37 °C for 18–48 hours. Yeast was identified following standard procedures. Antifungal susceptibility testing was determined by the disk diffusion method according to the CLSI guideline. Descriptive statistics and logistical regressions were used to estimate the crude ratio with a 95% confidence interval. P-value < 0.05 was considered significant. Among 68 individuals referred to the mycology lab, the result of direct examination and culture of all patients approved for C.albicans. Of these, 38 individuals (55.8%) were male, and 30 (44.2%) were female. The patients' age ranges were between one month and an 18-year-old. In the study of infection intensity, the patients were classified into three levels such as few (73.5%), moderate (20.6%), and many (5.9%). In the present study, all the patients were sensitive to Posaconazole. Also, the eagle effect was found in Amphotericin B, Voriconazole, and Fluconazole with frequencies of 91.7%, 91.7%, and 83%, respectively. In addition, just 8.3% of isolates were resistant to Itraconazole. It has not shown resistance in other mentioned medicine. The patients showed an intermediate response to Itraconazole (91.7%), Fluconazole (17%), Voriconazole (8.3%), and Amphotericin B (8.3%). There is a high prevalence of yeast infections in children with suspected UTIs. Also, boys are more likely to get yeast infections, and the severity of the infection is higher than girls. The present study demonstrated the importance of diagnosing and selecting the appropriate drug for urinary tract fungal infections in hospitalized children.

Keywords: urinary tract infections, children, fungal infections, yeast, antifungal susceptibility

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Authors: Dua Masarwa, Yulia Niazov, Merav Ben Natan, Dina Mostovoy

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Background: the aimed to explore the role of parental health beliefs in parent seeking of eye examinations for their children, using the Health Belief Model. Methods: In this quantitative correlational survey study, 100 parents who presented to Barzilai University Medical Center in July 2021 to perform an eye examination to their child completed a questionnaire. Results: Only 29.6% of the parents knew that a vision screening is performed in first grade, and 10% of the parents were unsure about where to find local eye care for their kids. Moreover, 19% of the parents indicated that they were concerned that their child would be prescribed glasses unnecessarily, and 10% believed that wearing glasses would weaken their child's eyes. Various parental health beliefs regarding children's eye examinations were found associated with parent seeking of eye examinations for their child. Thus, perceived susceptibility (r = 0.52, p < 0.01), perceived benefits (r = 0.39, p < 0.01), and perceived barriers (r=-0.31, p < 0.01) are associated with parent seeking of eye examinations for their child. Also, parents' level of knowledge was associated with seeking eye examinations for their child (r = 0.20, p < 0.01). Conclusion: Parent perceptions of the child's susceptibility to vision problems and perceived barriers to seeking eye examinations predicted parents seeking of eye examinations for their child. Interventions aimed at increasing timely eye examinations among children should focus on raising parent awareness of vision problems in childhood, dispelling misconceptions, and providing parents with practical information regarding available services.

Keywords: children, parents, eye examination, health beliefs, vision problems

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Authors: Adepeju Simon-Oke, Olatunji Odeyemi, Mobolanle Oniya

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Urinary tract infection has become the most common bacterial infections in humans, both at the community and hospital settings; it has been reported in all age groups and in both sexes. This study was carried out in order to determine and evaluate the prevalence, current drug susceptibility pattern of the isolated organisms and identify the associated risk factors of UTIs among the pregnant women in Akure, Ondo State, Nigeria. A cross-sectional study was conducted on the urine of pregnant women, and socio-demographic information of the women was collected. A total of 300 clean midstream urine samples were collected, and a general urine microscopic examination and culture were carried out, the Microbact identification system was used to identify gram-negative bacteria. Out of the 300 urine samples cultured, 183(61.0%) yielded significant growth of urinary pathogens while 117(39.0%) yielded either insignificant growth or no growth of any urinary pathogen. Prevalence of UTI was significantly associated with the type of toilet used, symptoms of UTI, and previous history of urinary tract infection (p<0.05). Escherichia coli 58(31.7%) was the dominant pathogen isolated, and the least isolated uropathogens were Citrobacter freudii and Providencia retgerri 2(1.1%) respectively. Gram-negative bacteria showed 77.6%, 67.9%, and 61.2% susceptibility to ciprofloxacin, augmentin, and chloramphenicol, respectively. Resistance against septrin, chloramphenicol, sparfloxacin, amoxicillin, augmentin, gentamycin, pefloxacin, trivid, and streptomycin was observed in the range of 23.1 to 70.1%. Gram-positive uropathogens isolated showed high resistance to amoxicillin (68.4%) and high susceptibility to the remaining nine antibiotics in the range 65.8% to 89.5%. This study justifies that pregnant women are at high risk of UTI. Therefore screening of pregnant women during antenatal clinics should be considered very important to avoid complications. Health education with regular antenatal and personal hygiene is recommended as precautionary measures to UTI.

Keywords: pregnant women, prevalence, risk factor, UTIs

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Authors: Awad A. Younis, Elise Stronberg, Shifa Noor

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Malware attacks due to end-user vulnerabilities have been noticeably increased in the past few years. Investigating the factors that make an end-user vulnerable to those attacks is critical because they can be utilized to set up proactive strategies such as awareness and education to mitigate the impacts of those attacks. Some existing studies investigated demographic, behavioral, and cultural factors that make an end-user susceptible to malware attacks. However, it has been challenging to draw more general conclusions from individual studies due to the varieties in the type of end-users and different types of malware. Therefore, we conducted a systematic literature review (SLR) of the existing research for end-user susceptibility factors to malware attacks. The results showed while some demographic factors are mostly associated with malware infection regardless of the end users' type, age, and gender are not consistent among the same and different types of end-users. Besides, the association of culture and personality factors with malware infection are consistent in most of the selected studies and for all type of end-users. Moreover, malware infection varies based on age, geographic location, and host types. We propose that future studies should carefully take into consideration the type of end-users because different end users may be exposed to different threats or be targeted based on their user domains’ characteristics. Additionally, as different types of malware use different tactics to trick end-users, taking the malware types into consideration is important.

Keywords: cybersecurity, malware, end-users, demographics, personality, culture, systematic literature review

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Authors: Masoud Abbasalipour

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In this study, the impact of family status on individuals, involving factors such as parents' literacy level, family size, individuals' blood group, and susceptibility to addiction, was investigated. Statistical tests were employed to scrutinize the relationships among these specified factors. The statistical population of the study consisted of 338 samples divided into two groups: individuals with addiction and those without addiction in the city of Amol. The addicted group was selected from individuals visiting the substance abuse treatment center in Amol, and the non-addicted group was randomly selected from individuals in urban and rural areas. The Chi-square test was used to examine the presence or absence of relationships among the variables, and Kramer's V test was employed to determine the strength of the relationship between them. Excel software facilitated the initial entry of data, and SPSS software was utilized for the desired statistical tests. The research results indicated a significant relationship between the variable of parents' education level and individuals' addiction. The analysis showed that the education level of their parents was significantly lower compared to non-addicted individuals. However, the variables of the number of family members and blood group did not significantly impact individuals' susceptibility to addiction.

Keywords: addiction, blood group, parents' literacy level, family status

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Authors: Ghazi Chabchoub, Mouna Feki, Mohamed Abid, Hammadi Ayadi

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Autoimmune thyroid diseases (AITDs), including Graves’ disease (GD) and Hashimoto’s thyroiditis (HT), are inherited as complex traits. Genetic factors associated with AITDs have been tentatively identified by candidate gene and genome scanning approaches. We analysed three intragenic microsatellite markers in the thyroid hormone receptor associated protein 2 gene (THRAP2), mapped near D12S79 marker, which have a potential role in immune function and inflammation [THRAP2-1(TG)n, THRAP2-2 (AC)n and THRAP2-3 (AC)n]. Our study population concerned 12 patients affected with AITDs belonging to a multiplex Tunisian family with high prevalence of AITDs. Fluorescent genotyping was carried out on ABI 3100 sequencers (Applied Biosystems USA) with the use of GENESCAN for semi-automated fragment sizing and GENOTYPER peak-calling software. Statistical analysis was performed using the non parametric Lod score (NPL) by Merlin software. Merlin outputs non-parametric NPLall (Z) and LOD scores and their corresponding asymptotic P values. The analysis for three intragenic markers in the THRAP2 gene revealed strong evidence for linkage (NPL=3.68, P=0.00012). Our results suggested the possible role of THRAP2 gene in AITDs susceptibility in this family.

Keywords: autoimmunity, autoimmune disease, genetic, linkage analysis

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Authors: Oladejo Olagoke Peter, Adagunodo T. A., Ogunkoya C. O.

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The research investigated the arrangement of some geological features under Ilesa employing aeromagnetic data. The obtained data was subjected to various data filtering and processing techniques, which are Total Horizontal Derivative (THD), Depth Continuation and Analytical Signal Amplitude using Geosoft Oasis Montaj 6.4.2 software. The Reduced to the Equator –Total Magnetic Intensity (TRE-TMI) outcomes reveal significant magnetic anomalies, with high magnitude (55.1 to 155 nT) predominantly at the Northwest half of the area. Intermediate magnetic susceptibility, ranging between 6.0 to 55.1 nT, dominates the eastern part, separated by depressions and uplifts. The southern part of the area exhibits a magnetic field of low intensity, ranging from -76.6 to 6.0 nT. The lineaments exhibit varying lengths ranging from 2.5 and 16.0 km. Analyzing the Rose Diagram and the analytical signal amplitude indicates structural styles mainly of E-W and NE-SW orientations, particularly evident in the western, SW and NE regions with an amplitude of 0.0318nT/m. The identified faults in the area demonstrate orientations of NNW-SSE, NNE-SSW and WNW-ESE, situated at depths ranging from 500 to 750 m. Considering the divergence magnetic susceptibility, structural style or orientation of the lineaments, identified fault and their depth, these lithological features could serve as a valuable foundation for assessing ground motion, particularly in the presence of sufficient seismic energy.

Keywords: lineament, aeromagnetic, anomaly, fault, magnetic

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Authors: Benyam Zenebe, Tesfaye Sisay, Gurja Belay, Workabeba Abebe

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Background: The prevalence and antibiogram of pathogenic E. coli strains, which cause diarrhea vary from region to region, and even within countries in the same geographical area. In Ethiopia, diagnostic approaches to E. coli induced diarrhea in children less than five years of age are not standardized. The aim of this study was to determine the involvement of pathogenic E. coli strains in child diarrhea and determine the antibiograms of the isolates in children less than 5 years of age with diarrhea at Addis Ababa University College of Health Sciences TikurAnbessa Specialized Hospital, Addis Ababa, Ethiopia. Methods: A purposive study that included 98 diarrheic children less than five years of age was conducted at Addis Ababa University College of Health Sciences, TikurAnbessa Specialized Hospital, Addis Ababa, Ethiopia to detect pathogenic E. coli biotypes. Stool culture was used to identify presumptive E. coliisolates. Presumptive isolates were confirmed by biochemical tests, and antimicrobial susceptibility tests were performed on confirmed E. coli isolates by the disk diffusion method. DNA was extracted from confirmed isolates by a heating method and subjected to Polymerase Chain Reaction or the presence of virulence genes. Amplified PCR products were analyzed by agarose gel electrophoresis. Data were collected on child demographics and clinical conditions using administered questionnaires. The prevalence of E. coli strains from the total diarrheic children, and the prevalence of pathogenic strains from total E. coli isolates along with their susceptibility profiles; the distribution of pathogenic E.coli biotypes among different age groups and between the sexes were determined by using descriptive statistics. Result: Out of 98 stool specimens collected from diarrheic children less than 5 years of age, 75 presumptive E. coli isolates were identified by culture; further confirmation by biochemical tests showed that only 56 of the isolates were E. coli; 29 of the isolates were found in male children and 27 of them in female children. Out of the 58 isolates of E. coli, 25 pathotypes belonging to different classes of pathogenic strains: STEC, EPEC, EHEC, EAEC were detected by using the PCR technique. Pathogenic E. coli exhibited high rates of antibiotic resistance to many of the antibiotics tested. Moreover, they exhibited multiple drug resistance. Conclusion: This study found that the isolation rate of E. coli and the involvement of antibiotic-resistant pathogenic E. coli in diarrheic children is prominent, and hence focus should be given on the diagnosis and antimicrobial sensitivity testing of pathogenic E. coli at Addis Ababa University College of Health Sciences TikurAnbessa Specialized Hospital. Among antibiotics tested, Cefotitan could be a drug of choice to treat E. coli.

Keywords: antibiotic susceptibility profile, children, diarrhea, E. coli, pathogenic

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Authors: Dhouibi Mohamed, Stirbu Bogdan, Chabotier André, Pirlot Marc

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Effects of erosion and wear on the performance of small caliber guns have been analyzed throughout numerical and experimental studies. Mainly, qualitative observations were performed. Correlations between the volume change of the chamber and the maximum pressure are limited. This paper focuses on the development of a numerical model to predict the maximum pressure evolution when the interior shape of the chamber changes in the different weapon’s life phases. To fulfill this goal, an experimental campaign, followed by a numerical simulation study, is carried out. Two test barrels, « 5.56x45mm NATO » and « 7.62x51mm NATO,» are considered. First, a Coordinate Measuring Machine (CMM) with a contact scanning probe is used to measure the interior profile of the barrels after each 300-shots cycle until their worn out. Simultaneously, the EPVAT (Electronic Pressure Velocity and Action Time) method with a special WEIBEL radar are used to measure: (i) the chamber pressure, (ii) the action time, (iii) and the bullet velocity in each barrel. Second, a numerical simulation study is carried out. Thus, a coupled interior ballistic model is developed using the dynamic finite element program LS-DYNA. In this work, two different models are elaborated: (i) coupled Eularien Lagrangian method using fluid-structure interaction (FSI) techniques and a coupled thermo-mechanical finite element using a lumped parameter model (LPM) as a subroutine. Those numerical models are validated and checked through three experimental results, such as (i) the muzzle velocity, (ii) the chamber pressure, and (iii) the surface morphology of fired projectiles. Results show a good agreement between experiments and numerical simulations. Next, a comparison between the two models is conducted. The projectile motions, the dynamic engraving resistances and the maximum pressures are compared and analyzed. Finally, using this obtained database, a statistical correlation between the muzzle velocity, the maximum pressure and the chamber volume is established.

Keywords: engraving process, finite element analysis, gun barrel erosion, interior ballistics, statistical correlation

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Authors: George Shaker, Maike Eylert

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Recurrent urinary tract infections (UTIs) in patients with mesh implants, particularly following pelvic or abdominal surgeries, pose significant clinical challenges. This paper investigates whether flexible cystoscopy is an essential diagnostic and therapeutic tool in managing such patients. With the increasing prevalence of mesh-related complications, it is crucial to explore how diagnostic procedures like cystoscopy can aid in identifying mesh-associated issues that contribute to recurrent UTIs. While flexible cystoscopy is commonly used to evaluate lower urinary tract conditions, its necessity in cases involving patients with mesh implants remains under debate. This study aims to determine the value of flexible cystoscopy in identifying complications such as mesh erosion, fistula formation, and chronic inflammation, which may contribute to recurrent infections. The research compares patients who underwent flexible cystoscopy to those managed without this procedure, examining the diagnostic yield of cystoscopy in detecting mesh-related complications. Furthermore, the study investigates the relationship between recurrent UTIs and the mechanical effects of mesh on the urinary tract, as well as the potential for cystoscopy to guide treatment decisions, such as mesh removal or revision. The results indicate that while flexible cystoscopy can identify mesh-related complications in some cases, its routine use may not be necessary for all patients with recurrent UTIs and mesh. The study emphasizes the importance of patient selection, clinical history, and symptom severity in deciding whether to employ cystoscopy. In cases where there are clear signs of mesh erosion or unexplained recurrent infections despite standard treatments, cystoscopy proves valuable. However, the study also highlights potential risks and discomfort associated with the procedure, suggesting that cystoscopy should be reserved for select cases where non-invasive methods fail to provide clarity. The research concludes that while flexible cystoscopy remains a valuable tool in certain cases, its routine use for all patients with recurrent UTIs and mesh is not justified. The paper provides recommendations for clinical guidelines, emphasizing a more personalized approach to diagnostics that considers the patient’s overall condition, infection history, and mesh type.

Keywords: flexible cystoscopy, recurrent urinary tract infections, mesh implants, mesh erosion, diagnostic procedures, urology

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Authors: Ali Ghorbanipour

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The aim of this study is to investigate the drug resistance pattern and the value of the MIC (minimum inhibitory concentration)method to reduce the impact of infectious diseases and the slow development of resistance. Method: The study was conducted on clinical specimens collected between 2018 to 2021. identification of isolates and antibiotic susceptibility testing were performed using conventional biochemical tests. Antibiotic resistance was determined using kibry-Bauer disk diffusion and MIC by E-test methods comparative with microdilution plate elisa method. Results were interpreted according to CLSI. Results: Out of 249600 different clinical specimens, 18720 different pathogenic bacteria by overall detection ratio 7.7% were detected. Among pathogen bacterial were Gram negative bacteria (70%,n=13000) and Gram positive bacteria(30%,n=5720).Medically relevant gram-negative bacteria include a multitude of species such as E.coli , Klebsiella .spp , Pseudomonas .aeroginosa , Acinetobacter .spp , Enterobacterspp ,and gram positive bacteria Staphylococcus.spp , Enterococcus .spp , Streptococcus .spp was isolated . Conclusion: Our results highlighted that the resistance ratio among Gram Negative bacteria and Gram positive bacteria with different infection is high it suggest constant screening and follow-up programs for the detection of antibiotic resistance and the value of MIC drug susceptibility reporting that provide a new way to the usage of resistant antibiotic in combination with other antibiotics or accurate weight of antibiotics that inhibit or kill bacteria. Evaluation of wrong medication in the expansion of resistance and side effects of over usage antibiotics are goals. Ali ghorbanipour presently working as a supervision at the microbiology department of Massoud medical laboratory. Iran. Earlier, he worked as head department of pulmonary infection in firoozgarhospital, Iran. He received master degree in 2012 from Fergusson College. His research prime objective is a biologic wound dressing .to his credit, he has Published10 articles in various international congresses by presenting posters.

Keywords: antimicrobial profile, MIC & MBC Method, microplate antimicrobial assay, E-test

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Authors: Fateme Nokhodchi Bonab

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Studies related to magnetic resonance imaging (MRI) and drug delivery are reviewed in this study to demonstrate the role of transport theory in porous media in facilitating advances in biomedical applications. Diffusion processes are believed to be important in many therapeutic modalities such as: B. Delivery of drugs to the brain. We analyse the progress in the development of diffusion equations using the local volume average method and the evaluation of applications related to diffusion equations. Torsion and porosity have significant effects on diffusive transport. In this study, various relevant models of torsion are presented and mathematical modeling of drug release from biodegradable delivery systems is analysed. In this study, a new model of drug release kinetics from porous biodegradable polymeric microspheres under bulk and surface erosion of the polymer matrix is presented. Solute drug diffusion, drug dissolution from the solid phase, and polymer matrix erosion have been found to play a central role in controlling the overall drug release process. This work paves the way for MRI and drug delivery researchers to develop comprehensive models based on porous media theory that use fewer assumptions compared to other approaches.

Keywords: MRI, porous media, drug delivery, biomedical applications

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Authors: A. Alyami, S. Christmas, K. Neeltje, G. Pollakis, B. Paxton, Z. Al-Bayati

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The Human leukocyte antigen-G (HLA-G) molecule plays an important role in immunomodulation. To date, 16 untranslated regions (UTR) HLA-G haplotypes have been previously defined by sequenced SNPs in the coding region. From these, UTR-1, UTR-2, UTR-3, UTR-4, UTR-5, UTR-6 and UTR-7 are the most frequent 3’UTR haplotypes at the global level. UTR-1 is associated with higher levels of soluble HLA-G and HLA-G expression, whereas UTR-5 and UTR-7 are linked with low levels of soluble HLA-G and HLA-G expression. Human immunodeficiency virus type 1 (HIV-1) infection results in the progressive loss of immune function in infected individuals. The virus escape mechanism typically includes T lymphocytes and NK cell recognition and lyses by classical HLA-A and B down-regulation, which has been associated with non-classical HLA-G molecule up-regulation, respectively. We evaluated the haplotypes of the HLA-G 3′ untranslated region frequencies observed in three HIV-1 groups from the Netherlands and their susceptibility to develop infection. The three groups are made up of mainly men who have sex with men (MSM), injection drug users (IDU) and a high-risk-seronegative (HRSN) group. DNA samples were amplified with published primers prior sequencing. According to our results, the low expresser frequencies show higher in HRSN compared to other groups. This is indicating that 3’UTR polymorphisms may be identified as potential prognostic biomarkers to determine susceptibility to HIV.

Keywords: Human leukocyte antigen-G (HLA-G) , men who have sex with men (MSM), injection drug users (IDU), high-risk-seronegative (HRSN) group, high-untranslated region (UTR)

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Authors: Issamaldin Mohammed, Ahmed Abdalla, Hatim Elobied

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Soil erosion is globally known for adverse effects on social, environmental and economical aspects which directly or indirectly influence the human life. The area under study suffers from problems like water quality, river and agricultural canals bed rise due to high sediment load brought by Algash River from upstream (Eritrea high land), the current study utilized from remote sensing and Geographical Information System (GIS) to estimate the annual soil loss using Universal Soil Loss Equation (USLE). The USLE is widely used over the world which basically relies on rainfall erosivity factor (R), soil erodibility factor (K), topographic factor (LS), cover management factor (C) and support practice factor (P). The result of the study showed high soil loss in the study area, this result was illustrated in a form of map presenting the spatial distribution of soil loss amounts which classified into seven zones ranging from very slight zone (less than 2 ton/ha.year) to very severe (100-500 ton/ha.year), also the total soil loss from the whole study area was found to be 32,916,840.87 ton/ha.year. These kinds of results will help the experts of land management to give a priority for the severely affected zones to be tackled in an appropriate way.

Keywords: Geographical Information System, remote sensing, sedimentation, soil loss

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Authors: Freitas Vania Moreira, Rodrigues B. B., Araujo M.B., Silva D. R., Sousa A. C., Araujo K. P., Pimentel R. R., Cares J. E., Junqueira N. T. V.

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The Pitahayas are cactus native from America and abundant in arid regions. The cultivation is based mainly on the following species: Hylocereus undatus, H. polyrhizus, H. setaceus and H. megalanthus, being H. undatus the most cultivated in Brazil. The pitahaya cultivation is recent in Brazil and is concentrated in São Paulo. Meloidogyne enterolobii is of unknown origin being distributed in several countries. This nematode has recently been detected in Brazil causing damage in several crops. Similarly, M. incognita is a widely distributed pathogen in Brazil. The objective of this study is to evaluate the following accesses of pitahaya to M. enterolobii: CPAC- Py H. hundatus 01, 02, 03, 04, 05, 06, 07 and 08; CPAC - Py H. costaricense 8A; CPAC - Py Selenicereus setaceus 17 and CPAC - Py S. megalantus 22. And the following accesses to M. incognita: CPAC- Py H. hundatus 05; CPAC - Py H. costaricense 8A; CPAC - Py S. setaceus 17 and CPAC - Py S. megalantus 22. According to the results, CPAC – Py H. hundatus 01, 02, 03, 04 and 07 were considered resistant. While CPAC - Py 05 and 08 was susceptible. CPAC-Py 06 also was considered susceptible, because there was the reaction of susceptibility in one of the trials. Given this wide diversity in H. hundatus and being this species the most cultivated in Brazil it is suggested to work more with this material in Embrapa Cerrados. CPAC - Py H. costaricense 8A behaved as susceptible in one of the trials. CPAC - Py S. setaceus 17 and CPAC – Py S. megalantus 22 were considered highly susceptible. The susceptibility of S. megalantus is widely described in the literature. In relation to M. incognita, there were differences between the results in both experiments, but all behaved as susceptible in at least one of the tests.

Keywords: pitaya, meloidogyne, fruit, resistance

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Authors: Exa Heydemans, Jessica Sjah, Dwinanti Rika Marthanty

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This paper presents numerical simulations using an open boundary algorithm with modified dynamic boundary condition (mDBC) for weakly compressible smoothed particle hydrodynamics models from particle-based code Dualsphysics. The problems of piping erosion in dams and dikes are aimed for studying the algorithm. The case 2D model of unsteady fluid flow past around a fixed cylinder is simulated, where various values of Reynold’s numbers (Re40, Re60, Re80, and Re100) and different model’s resolution are considered. A constant velocity with different values of viscosity for generating various Reynold’s numbers and different numbers of particles over a cylinder for the resolution are modeled. The interaction between solid particles of the cylinder and fluid particles is concerned. The cylinder is affected by the hydrodynamics force caused by the flow of fluid particles. The solid particles of the cylinder are the observation points to obtain force and pressure due to the hydrodynamics forces. As results of the simulation, which is to show the capability to model 2D unsteady with various Reynold’s numbers, the pressure coefficient, drag coefficient, lift coefficient, and Strouhal number are compared to the previous work from literature.

Keywords: hydrodynamics, internal erosion, dualsphysics, viscous fluid flow

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Authors: Prachi Choudhary, Jai Gopal Sharma

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Microbial cultures determine the type of organism, its abundance in the tested sample, or both. It is one of the primary diagnostic methods of microbiology. It is used to determine the cause of infectious disease by letting the agent multiply in a predetermined medium. Different bacteria produce colonies that may be very distinct from the bacterial species that produced them. To culture any pathogen or microorganism, we should first know about the types of media used in microbiology for culturing. Sometimes sub culturing is also done in various microorganisms if some mixed growth is seen in culture. Nearly 3 types of culture media based on consistency – solid, semi-solid, and liquid (broth) media; are further explained in the report. Then, The Five I's approach is a method for locating, growing, observing, and characterizing microorganisms, including inoculation and incubation. Isolation, inspection, and identification. For identification of bacteria, we have to culture the sample like urine, sputum, blood, etc., on suitable media; there are different methods of culturing the bacteria or microbe like pour plate method, streak plate method, swabbing by needle, pipetting, inoculation by loop, spreading by spreader, etc. After this, we see the bacterial growth after incubation of 24 hours, then according to the growth of bacteria antibiotics susceptibility test is conducted; this is done for sensitive antibiotics or resistance to that bacteria, and also for knowing the name of bacteria. Various methods like the dilution method, disk diffusion method, E test, etc., do antibiotics susceptibility tests. After that, various medicines are provided to the patients according to antibiotic sensitivity and resistance.

Keywords: inoculation, incubation, isolation, antibiotics suspectibility test, characterizing

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Authors: Cai J. T. Ladd, Mollie F. Duggan-Edwards, Tjeerd J. Bouma, Jordi F. Pages, Martin W. Skov

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Salt marshes are valued for their role in coastal flood protection, carbon storage, and for supporting biodiverse ecosystems. As a biogeomorphic landscape, marshes evolve through the complex interactions between sea level rise, sediment supply and wave/current forcing, as well as and socio-economic factors. Climate change and direct human modification could lead to a global decline marsh extent if left unchecked. Whilst the processes of saltmarsh erosion and expansion are well understood, empirical evidence on the key drivers of long-term lateral marsh dynamics is lacking. In a GIS, saltmarsh areal extent in 25 estuaries across Great Britain was calculated from historical maps and aerial photographs, at intervals of approximately 30 years between 1846 and 2016. Data on the key perceived drivers of lateral marsh change (namely sea level rise rates, suspended sediment concentration, bedload sediment flux rates, and frequency of both river flood and storm events) were collated from national monitoring centres. Continuous datasets did not extend beyond 1970, therefore predictor variables that best explained rate change of marsh extent between 1970 and 2016 was calculated using a Partial Least Squares Regression model. Information about the spread of Spartina anglica (an invasive marsh plant responsible for marsh expansion around the globe) and coastal engineering works that may have impacted on marsh extent, were also recorded from historical documents and their impacts assessed on long-term, large-scale marsh extent change. Results showed that salt marshes in the northern regions of Great Britain expanded an average of 2.0 ha/yr, whilst marshes in the south eroded an average of -5.3 ha/yr. Spartina invasion and coastal engineering works could not explain these trends since a trend of either expansion or erosion preceded these events. Results from the Partial Least Squares Regression model indicated that the rate of relative sea level rise (RSLR) and availability of suspended sediment concentration (SSC) best explained the patterns of marsh change. RSLR increased from 1.6 to 2.8 mm/yr, as SSC decreased from 404.2 to 78.56 mg/l along the north-to-south gradient of Great Britain, resulting in the shift from marsh expansion to erosion. Regional differences in RSLR and SSC are due to isostatic rebound since deglaciation, and tidal amplitudes respectively. Marshes exposed to low RSLR and high SSC likely leads to sediment accumulation at the coast suitable for colonisation by marsh plants and thus lateral expansion. In contrast, high RSLR with are likely not offset deposition under low SSC, thus average water depth at the marsh edge increases, allowing larger wind-waves to trigger marsh erosion. Current global declines in sediment flux to the coast are likely to diminish the resilience of salt marshes to RSLR. Monitoring and managing suspended sediment supply is not common-place, but may be critical to mitigating coastal impacts from climate change.

Keywords: lateral saltmarsh dynamics, sea level rise, sediment supply, wave forcing

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Authors: Hadura Abu Hasan, Zairi Jaal, P. J. McCall

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Dengue is a serious problem in Malaysia, particularly in high-density urban communities with lower socio-economic levels. This study evaluated the susceptibility of local populations of Aedesaegypti (Linnaeus), Aedesalbopictus (Skuse) and Culexquinquefasciatus (Say) from the traditional community of BaganDalam, Penang, Malaysia to lambdacyhalothrin and pirimiphos-methyl using standard World Health Organization (WHO) adult bioassay test. Unfed female mosquitoes aged 3-5 days were exposed to WHO recommended dosages of insecticides over fixed time periods with results presented as knock-down time (KT50) for each strain.The insecticide susceptible VCRU laboratory strain was usedas control. All three specieswere highly resistant to lambda-cyhalothrin with less than 10% mortality at 24 hours after treatment. In contrast, Ae.aegypti and Ae. albopictus were susceptible to pirimiphos-methyl, showing 100% mortality recorded 24 hoursafter treatment. Cx. quinquefasciatuswasclassed as ‘suspected resistant’ to pirimiphos-methyl as mortality recorded 24 hours after treatment was 94-96%. The results indicate that organophosphates such as pirimiphos-methyl might be used as alternative to pyrethroid for dengue vector control in this dengue-prone area.

Keywords: vector control, aedes aegypti, aedes albopictus, dengue, culex quinquefasciatus, residuals insecticides, pyrethroid, organophosphate, resistant, mosquito

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Authors: Abbas Ahmadi, Bijan Raie, Mohammad Reza Neyshabouri, Mohammad Ali Ghorbani, Farrokh Asadzadeh

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In recent years, vast areas of Urmia Lake in Dasht-e-Tabriz has dried up leading to saline sediments exposure on the surface lake coastal areas being highly susceptible to wind erosion. This study was conducted to investigate wind erosion and its relevance to soil physicochemical properties and also modeling of wind erodibility (WE) using artificial intelligence techniques. For this purpose, 96 soil samples were collected from 0-5 cm depth in 414000 hectares using stratified random sampling method. To measure the WE, all samples (<8 mm) were exposed to 5 different wind velocities (9.5, 11, 12.5, 14.1 and 15 m s-1 at the height of 20 cm) in wind tunnel and its relationship with soil physicochemical properties was evaluated. According to the results, WE varied within the range of 76.69-9.98 (g m-2 min-1)/(m s-1) with a mean of 10.21 and coefficient of variation of 94.5% showing a relatively high variation in the studied area. WE was significantly (P<0.01) affected by soil physical properties, including mean weight diameter, erodible fraction (secondary particles smaller than 0.85 mm) and percentage of the secondary particle size classes 2-4.75, 1.7-2 and 0.1-0.25 mm. Results showed that the mean weight diameter, erodible fraction and percentage of size class 0.1-0.25 mm demonstrated stronger relationship with WE (coefficients of determination were 0.69, 0.67 and 0.68, respectively). This study also compared efficiency of multiple linear regression (MLR), gene expression programming (GEP), artificial neural network (MLP), artificial neural network based on genetic algorithm (MLP-GA) and artificial neural network based on whale optimization algorithm (MLP-WOA) in predicting of soil wind erodibility in Dasht-e-Tabriz. Among 32 measured soil variable, percentages of fine sand, size classes of 1.7-2.0 and 0.1-0.25 mm (secondary particles) and organic carbon were selected as the model inputs by step-wise regression. Findings showed MLP-WOA as the most powerful artificial intelligence techniques (R2=0.87, NSE=0.87, ME=0.11 and RMSE=2.9) to predict soil wind erodibility in the study area; followed by MLP-GA, MLP, GEP and MLR and the difference between these methods were significant according to the MGN test. Based on the above finding MLP-WOA may be used as a promising method to predict soil wind erodibility in the study area.

Keywords: wind erosion, erodible fraction, gene expression programming, artificial neural network

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Authors: Gabrielle Robertson, Matthew Downs, Joseph Dagher

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Iron deposition in the brain has been linked with a host of neurological disorders such as Alzheimer’s, Parkinson’s, and Multiple Sclerosis. While some treatment options exist, there are no objective measurement tools that allow for the monitoring of iron levels in the brain in vivo. An emerging Magnetic Resonance Imaging (MRI) method has been recently proposed to deduce iron concentration through quantitative measurement of magnetic susceptibility. This is a multi-step process that involves repeated modeling of physical processes via approximate numerical solutions. For example, the last two steps of this Quantitative Susceptibility Mapping (QSM) method involve I) mapping magnetic field into magnetic susceptibility and II) mapping magnetic susceptibility into iron concentration. Process I involves solving an ill-posed inverse problem by using regularization via injection of prior belief. The end result from Process II highly depends on the model used to describe the molecular content of each voxel (type of iron, water fraction, etc.) Due to these factors, the accuracy and repeatability of QSM have been an active area of research in the MRI and medical imaging community. This work aims to estimate iron concentration in the brain via a single step. A synthetic numerical model of the human head was created by automatically and manually segmenting the human head on a high-resolution grid (640x640x640, 0.4mm³) yielding detailed structures such as microvasculature and subcortical regions as well as bone, soft tissue, Cerebral Spinal Fluid, sinuses, arteries, and eyes. Each segmented region was then assigned tissue properties such as relaxation rates, proton density, electromagnetic tissue properties and iron concentration. These tissue property values were randomly selected from a Probability Distribution Function derived from a thorough literature review. In addition to having unique tissue property values, different synthetic head realizations also possess unique structural geometry created by morphing the boundary regions of different areas within normal physical constraints. This model of the human brain is then used to create synthetic MRI measurements. This is repeated thousands of times, for different head shapes, volume, tissue properties and noise realizations. Collectively, this constitutes a training-set that is similar to in vivo data, but larger than datasets available from clinical measurements. This 3D convolutional U-Net neural network architecture was used to train data-driven Deep Learning models to solve for iron concentrations from raw MRI measurements. The performance was then tested on both synthetic data not used in training as well as real in vivo data. Results showed that the model trained on synthetic MRI measurements is able to directly learn iron concentrations in areas of interest more effectively than other existing QSM reconstruction methods. For comparison, models trained on random geometric shapes (as proposed in the Deep QSM method) are less effective than models trained on realistic synthetic head models. Such an accurate method for the quantitative measurement of iron deposits in the brain would be of important value in clinical studies aiming to understand the role of iron in neurological disease.

Keywords: magnetic resonance imaging, MRI, iron deposition, machine learning, quantitative susceptibility mapping

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Authors: Zegrar Ahmed, Ghabi Mohamed

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The degradation of arid and semi-arid ecosystems in Algeria has become a palpable fact that only hinders progress and rural development. In these exceptionally fragile environments, the decline of vegetation is done according to an alarming increase and wind erosion dominates. The ecosystem is subjected to a long hot dry season and low annual average rainfall. The urgency of the fight against desertification is imposed by the very nature of the process that tends to self-accelerate, resulting when human intervention is not forthcoming the irreversibility situations, preventing any possibility of restoration state of these zones. These phenomena have led to different degradation processes, such as the destruction of vegetation, soil erosion, and deterioration of the physical environment. In this study, the work is mainly based on the criteria for classification and identification of physical parameters for spatial analysis and multi-sources to determine the vulnerability of major steppe formations and their impact on desertification. we used Landsat data with two different dates March 2010 and November 2014 in order to determine the changes in land cover, sand moving and land degradation for the diagnosis of the desertification Phenomenon. The application, through specific processes, including the supervised classification was used to characterize the main steppe formations. An analysis of the vulnerability of plant communities was conducted to assign weights and identify areas most susceptible to desertification. Vegetation indices are used to characterize the steppe formations to determine changes in land use.

Keywords: remote sensing, SIG, ecosystem, degradation, desertification

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Authors: Minwuyelet Maru, Solomon Habtemariam, Endalamaw Gadissa, Abraham Aseffa

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Background: Tuberculosis is a major public health problem in Ethiopia. The burden of TB is aggravated by emergence and expansion of drug resistant tuberculosis and different lineages of Mycobacterium tuberculosis (M. tuberculosis) have been reported in many parts of the country. Describing strains of Mycobacterial isolates and drug susceptibility pattern is necessary. Method: Sputum samples were collected from smear positive pulmonary TB patients age >= 7 years between October 1, 2012 to September 30, 2013 and Mycobacterial strains isolated on Loweensten Jensen (LJ) media. Each strain was characterized by deletion typing and Spoligotyping. Drug sensitivity testing was determined with the indirect proportion method using Middle brook 7H10 media and association to determine possible risk factors to drug resistance was done. Result: A total of 144 smear positive pulmonary tuberculosis patients were enrolled. The age of participants ranged from 7 to 78 with mean age of 29.22 (±10.77) years. In this study 82.2% (n=97) of the isolates were sensitive to the four first line anti-tuberculosis drugs and resistance to any of the four drugs tested was 17.8% (n=21). A high frequency of any resistance was observed in isoniazid, 13.6%, (n=16) followed by streptomycin, 11.8% (n=14). No significant association of isoniazid resistance with HIV, sex and history of previous TB treatment was observed but there was significant association with age, high between 31-35 years of age (p=0.01). Majority, 89.9% (n=128) of participants were new cases and only 11.1% (n=16) had history of previous TB treatment. No MDR-TB from new cases and 2 MDRTB (13.3%) was isolated from re-treatment cases which was significantly associated with previous TB treatment (p<0.01). Thirty two different types of spoligotype patterns were identified and 74.1% were grouped in to 13 clusters. The dominant strains were SIT 25, 18.1% (n=21), SIT 53, 17.2% (n=20) and SIT 149, 8.6% (n=10). Lineage 4 is the predominant lineage followed by lineage 3 and lineage 7 comprising 65.5% (n=76), 28.4% (n=33) and 6% (n=7) respectively. Majority of strains from lineage 3 and 4 were SIT 25 (63.6%) and SIT 53 (26.3%) whereas SIT 343 was the dominant strain from lineage 7 (71.4%). Conclusion: Wide spread of lineage 3 and lineage 4 of the modern lineage and high number of strain cluster indicates high ongoing transmission. The high proportion resistance to any of the first line anti-tuberculosis drugs may be a potential source in the emergence of MDR-TB. Wide spread of SIT 25 and SIT 53 having a tendency of ease transmission and presence of higher resistance of isoniazid in working and mobile age group, 31-35 years of age may increase risk of drug resistant strains transmission.

Keywords: tuberculosis, drug susceptibility, strain diversity, lineage, Ethiopia, spoligotyping

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