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      • KCI등재

        Prevalence and Correlates of Low Back Pain in Primary Care: What Are the Contributing Factors in a Rapidly Developing Country

        Abdulbari Bener,Elnour Elnaeim Dafeeah,Khalid Alnaqbi 대한척추외과학회 2014 Asian Spine Journal Vol.8 No.3

        Study Design: Cross-sectional. Purpose: The purpose of the study was to determine the prevalence of low back pain (LBP) in the primary care setting with emphasis on the socio-demographic contributing factors and impact of LBP on lifestyle habits. Overview of Literature: LBP is one of the most common medical conditions seen in the Primary Health Care Clinic. Methods: A representative sample of 2,600 patients were approached and 1,829 subjects agreed to participate in this study (70.0%). Data on socio-demographic characteristics, life style habits and type of treatment were collected through a questionnaire. Results: The prevalence of LBP in the study sample was 56.5% (95% confidence interval, 54.2–58.8). LBP was more prevalent among women (53.9%) compared to men (46.1%). There was significant difference between male and female patients of LBP in terms of ethnicity (p <0.001), marital status (p =0.010), occupation (p <0.001), monthly household income (p =0.004), and cigarette/sheesha smokers (p <0.001). The percentages of different aspects of functional disabilities were statistically significantly higher among females compared to male patients with LBP. Almost a quarter of female patients with LBP (26%) and 18% male patients with LBP reported pain in the arms and legs (p =0.002). In addition, gastrointestinal complaints such as abdominal pain and food intolerance were significantly higher among female patients with LBP as compared to males (31% vs. 24.6%, p =0.018; and 25% vs. 18%, p =0.008, respectively). Complaints about headache and fainting were also significantly higher among female patients as compared to male LBP patients (43% vs. 36%, p =0.029; and 26% vs. 20%, p =0.016, respectively). The multivariate logistic regression revealed that being female, prolonged standing, prolonged sitting, heavy weight lifting, weakness in the legs, regular exercise, and cigarette/sheesh a smoking had a significant effect on the presence of LBP. Conclusions: LBP is highly prevalent among both genders and in older age. Also, weakness in the legs, smoking, prolonged standing and sitting had a significant effect on LBP. Furthermore, the current study findings support the fact that LBP continues to be an important clinical, social and economic, burden and a public health problem affecting the population of the entire world.

      • Date palm biochar-polymer composites: An investigation of electrical, mechanical, thermal and rheological characteristics

        Poulose, Anesh Manjaly,Elnour, Ahmed Yagoub,Anis, Arfat,Shaikh, Hamid,Al-Zahrani, S.M.,George, Justin,Al-Wabel, Mohammad I.,Usman, Adel R.,Ok, Yong Sik,Tsang, Daniel C.W.,Sarmah, Ajit K. Elsevier 2018 The Science of the total environment Vol.619 No.-

        <P><B>Abstract</B></P> <P>The application of biochar (BC) as a filler in polymers can be viewed as a sustainable approach that incorporates pyrolysed waste based value-added material and simultaneously mitigate bio-waste in a smart way. The overarching aim of this work was to investigate the electrical, mechanical, thermal and rheological properties of biocomposite developed by utilizing date palm waste-derived BC for the reinforcing of polypropylene (PP) matrix. Date palm waste derived BC prepared at (700 and 900°C) were blended at different proportions with polypropylene and the resultant composites (BC/PP) were characterized using an array of techniques (scanning electron microscope, energy-dispersive X-ray spectroscopy and Fourier transform infra-red spectroscopy). Additionally the thermal, mechanical, electrical and rheological properties of the BC/PP composites were evaluated at different loading of BC content (from 0 to15% w/w). The mechanical properties of BC/PP composites showed an improvement in the tensile modulus while that of electrical characterization revealed an enhanced electrical conductivity with increased BC loading. Although the BC incorporation into the PP matrix has significantly reduced the total crystallinity of the resulted composites, however; a positive effect on the crystallization temperature (T<SUB>c</SUB>) was observed. The rheological characterization of BC/PP composites revealed that the addition of BC had minimal effect on the storage modulus (G′) compared to the neat (PP).</P> <P><B>Highlights</B></P> <P> <UL> <LI> Date palm waste derived biochar was used as filler for polymer composites' applications. </LI> <LI> Biochar/polypropylene (BC/PP) composites' properties such as electrical, mechanical, thermal and rheological were investigated. </LI> <LI> The BC/PP composites' surface resistivity was decreased by four orders of magnitude. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

      • KCI등재

        Assessing Trees Diversity in Jebel Elgarrie Forest Reserve in the Blue Nile State, Sudan

        Dafa-Alla Mohamed Dafa-Alla,Ahmed Ibrahim Abuelbasher,Haytham Hashim Gibreel,Yousif Elnour Yagoub,Ahmed Ali Hassabelkreem Siddig,Ahmed Mustafa Morad Hasoba 강원대학교 산림과학연구소 2022 Journal of Forest Science Vol.38 No.3

        The study aims to examine population indices of mature trees in Jebel Elgarrie forest, Blue Nile State, Sudan. We used remote sensing techniques to stratify the forest into vegetation classes depending on tree density. We distributed 97 circular sample plots (0.1 ha) proportionally to the area of the vegetation classes. In each sample plot we identified, counted and recorded all mature trees (DBH ≥10 cm). We calculated frequency, density, abundance, richness, evenness and diversity for each species and we drew abundance rank curve of mature trees. We used One-Way ANOVA to test for differences (=0.05) in mean density (No./ha) of mature trees between vegetation classes. Results revealed that the forest was conveniently sub-divided into high density (C1), medium density (C2), low density (C3) and bare farm land (C4) classes. We identified fifteen tree species that belong to 10 families and 14 genera. Combretaceae and Fabaceae were the common families while Anogeissus leiocarpa was the most frequently occurring species. While species diversity varied between vegetation classes, diversity of the forest as a whole is low. While mean density of mature trees in C1, C2, C3 and C4 it was 100, 74, 10, and 0, respectively, it was 54 for the whole forest indicating low stocking, Following One-Way ANOVA, multiple comparisons revealed significant differences in mean density of mature trees between C1 & C3 and C2 & C3. The study provided empirical results on population indices of mature tree species, which would be of importance for successful management and conservation of the forest.

      • KCI등재

        Analysis of Composition and Diversity of Natural Regeneration of Woody Species in Jebel El Gerrie Dry Land Forest East of Blue Nile State, Sudan

        Abuelbashar, Ahmed Ibrahim,Ahmed, Dafa-Alla Mohamed Dafa-Alla,Siddig, Ahmed Ali Hassabelkreem,Yagoub, Yousif Elnour,Gibreel, Haithum Hashim Institute of Forest Science 2022 Journal of Forest Science Vol.38 No.2

        The study aims to assess composition, diversity and population indices of natural regeneration of woody species in Jebel El Gerrie forest reserve, Blue Nile State, Sudan. We conducted field work between December 2018 and January 2019. We used random sampling to collect vegetation data in the forest where we made a total of 90 circular sample plots (radius 17.84 m) and distributed them proportionally to the area of each of the four density-based vegetation classes of the forest i.e. high density (C1), medium density (C2), low density (C3) and crop land (C4). In each sample plot we identified all regenerating tree species and counted their regeneration frequencies. We calculated ecological metrics of regeneration frequency, density, abundance, richness, evenness, diversity and importance value index (IVI) and drew abundance rank curve. Results revealed that out of fifteen mature tree species present, natural regeneration of 8 species, which belong to 6 families, was observed. The relatively most frequently naturally regenerating and abundant species were Anogeissus leiocarpa and Combretum hartmannianum. Richness, evenness and diversity of regenerating species were 1.33, 0.82 and 1.7, respectively. One-way ANOVA (α=0.05) of mean regeneration densities disclosed that there were significant differences (F<sub>3,86</sub>=16.77, p=0.000) between C2 & C3 (p=0.000) and C2 & C4 (p=0.000). While regeneration of seven tree species were absent, two, two and four species were of good, poor and fair regeneration status, respectively. A comparison of mean density of natural regeneration with that of parent trees reflects a poor regeneration status of the forest. The study provides empirical results on the regeneration status of species and signifies the need for management interventions for species conservation and restoration, maintenance of biodiversity and sustainable production.

      • Exploratory Investigation for Some Universities' E-Learning Systems during Covid-19 Pandemic

        Fatima Rayan Awad, Ahmed,Thowiba E., Ahmed,Rashid A., Saeed,Elmustafa Sayed, Ali,Ghada Elnour Elterafi, Abdelrhman,Somia Yousif Ahmed, Abutiraima International Journal of Computer ScienceNetwork S 2022 International journal of computer science and netw Vol.22 No.12

        COVID pandemic has reshaped the world as it has been known to us and the education system is one of the most affected by it. Due to social distancing, quarantines and isolations have made it impossible for the knowledge transition to the masses using conventional methods. For cope with pandemic, the only other way available for some of the fortunate countries is the use of E-learning having somewhat the same traditional teaching method. This paper is concerned with the study of the preparedness of the learning system in some Sudanese universities due to the impact of the COVID-19 pandemic. Critical analysis has been performed to evaluate the current developing scenario, usage of the facilities available in open-source platforms, and the interaction of the universities folks with e-learning systems. The impact of such measures has been thoroughly investigated in this paper for Sudan which is already deprived of a proper education system. The investigation shows that the interact of the staff and the students with the system was acceptable where more than 85% of those enrolled to the system were interact properly and efficiently. The lecturers conducted through the platform were attended with more than 75% of the students. We also found that most of the lecturer were avoid to exam students by utilize the platform; where only 45% of the uploaded courses were conducted exams over Moodle platform. As Moodle is an open source and still need to be improved to be used for high examination credibility.

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