411 research outputs found

    Mitochondrial DNA structure in the Arabian Peninsula

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    <p>Abstract</p> <p>Background</p> <p>Two potential migratory routes followed by modern humans to colonize Eurasia from Africa have been proposed. These are the two natural passageways that connect both continents: the northern route through the Sinai Peninsula and the southern route across the Bab al Mandab strait. Recent archaeological and genetic evidence have favored a unique southern coastal route. Under this scenario, the study of the population genetic structure of the Arabian Peninsula, the first step out of Africa, to search for primary genetic links between Africa and Eurasia, is crucial. The haploid and maternally inherited mitochondrial DNA (mtDNA) molecule has been the most used genetic marker to identify and to relate lineages with clear geographic origins, as the African Ls and the Eurasian M and N that have a common root with the Africans L3.</p> <p>Results</p> <p>To assess the role of the Arabian Peninsula in the southern route, we genetically analyzed 553 Saudi Arabs using partial (546) and complete mtDNA (7) sequencing, and compared the lineages obtained with those present in Africa, the Near East, central, east and southeast Asia and Australasia. The results showed that the Arabian Peninsula has received substantial gene flow from Africa (20%), detected by the presence of L, M1 and U6 lineages; that an 18% of the Arabian Peninsula lineages have a clear eastern provenance, mainly represented by U lineages; but also by Indian M lineages and rare M links with Central Asia, Indonesia and even Australia. However, the bulk (62%) of the Arabian lineages has a Northern source.</p> <p>Conclusion</p> <p>Although there is evidence of Neolithic and more recent expansions in the Arabian Peninsula, mainly detected by (preHV)1 and J1b lineages, the lack of primitive autochthonous M and N sequences, suggests that this area has been more a receptor of human migrations, including historic ones, from Africa, India, Indonesia and even Australia, than a demographic expansion center along the proposed southern coastal route.</p

    Teaching competencies that the faculty member should have to ensure the quality of the educational process of learning

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    Teaching is considered as one of the most important jobs performed by the faculty member, and it is one of the most important functions of the university, therefore ensuring the quality of education is related to teaching quality which includes the skills, methods, and strategies that are followed by the faculty member to achieve the desired goals. As the teaching skills and the faculty member interest in teaching and taking care of his students are the most important characteristics of his professionalism from the perspective of university students, perhaps this is why educators and politicians considered “teacher’s professionalism “ is “good teaching”, and that the “professional teacher” is characterized by the expansion of his knowledge, and his understanding of pedagogy, in addition to commitment, enthusiasm, and creativity in teaching. Therefore, this study aimed to answer the following question:  What are the Teaching competencies that the faculty member should have to ensure the quality of the educational process of learning? The researchers used the descriptive approach through a survey of previous experiences at the level of local and international organizations, as well as the studies and the scientific researches that had the same subject of this study. The study concluded a set of the Teaching competencies that the faculty member should have to ensure the quality of the educational process of learning. Key words: Teaching competencies, The faculty member, Ensuring the quality of the educational process of learning

    Carriers of human mitochondrial DNA macrohaplogroup M colonized India from southeastern Asia

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    Background: From a mtDNA dominant perspective, the exit from Africa of modern humans to colonize Eurasia occurred once, around 60 kya, following a southern coastal route across Arabia and India to reach Australia short after. These pioneers carried with them the currently dominant Eurasian lineages M and N. Based also on mtDNA phylogenetic and phylogeographic grounds, some authors have proposed the coeval existence of a northern route across the Levant that brought mtDNA macrohaplogroup N to Australia. To contrast both hypothesis, here we reanalyzed the phylogeography and respective ages of mtDNA haplogroups belonging to macrohaplogroup M in different regions of Eurasia and Australasia.  Results: The macrohaplogroup M has a historical implantation in West Eurasia, including the Arabian Peninsula. Founder ages of M lineages in India are significantly younger than those in East Asia, Southeast Asia and Near Oceania. Moreover, there is a significant positive correlation between the age of the M haplogroups and its longitudinal geographical distribution. These results point to a colonization of the Indian subcontinent by modern humans carrying M lineages from the east instead the west side.  Conclusions: The existence of a northern route, previously proposed for the mtDNA macrohaplogroup N, is confirmed here for the macrohaplogroup M. Both mtDNA macrolineages seem to have differentiated in South East Asia from ancestral L3 lineages. Taking this genetic evidence and those reported by other disciplines we have constructed a new and more conciliatory model to explain the history of modern humans out of Africa

    Artificial Neural Network Heart Failure Prediction Using JNN

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    Heart failure is a major cause of death worldwide. Early detection and intervention are essential for improving the chances of a positive outcome. This study presents a novel approach to predicting the likelihood of a person having heart failure using a neural network model. The dataset comprises 918 samples with 11 features, such as age, sex, chest pain type, resting blood pressure, cholesterol, fasting blood sugar, resting electrocardiogram results, maximum heart rate achieved, exercise-induced angina, oldpeak, ST_Slope, and HeartDisease. A neural network model with four layers (1 input and 1 output) was trained on the dataset and achieved an accuracy of 90% and an average error of 0.009. The most influential factors in heart failure prediction were found to be oldpeak, ST_Slope, sex, fastingBS, chestPainType, exerciseAngina, cholesterol, restingBP, maxHR, restingBP, and age. This study provides a valuable tool for early detection and intervention of heart failure, thereby contributing to the field of health and medicine

    The Impact of the Organizational Justice on the Development of the Organizational Citizenship Behavior in Jordanian Press Organizations

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    This study aimed to explore the impact of the organizational justice on the development of organizational citizenship behavior in the Jordanian press organizations. The population for the present study consists of all workers in Jordanian press organizations. This population includes 1835 employees. They are working across four press organizations, which are Jordan Press Foundation, the company of Jordan Press and Publishing, the Arab Printers Company, and the company of Jordan United Press and Publishing. 204 questionnaires were distributed to collect the necessary data and to test hypotheses of this study. The empirical results revealed that there was a significant statistical impact of the organizational justice (equity of distributions, fairness of procedures and fairness of transactions) on the organizational citizenship. The study recommended that the development of organizational citizenship strongly depended on the deploying of the organizational justice through: (a)the fairness of tasks and duties distribution through across organization, (b) commensurate these tasks and duties with employees’ abilities, (c) distribution of incentives depending on the merits of employees, (d) participation in decision making process supported the organizational citizenship and developed justice practices, (e) transparency through providing sufficient information and discussing work-related decisions found for the organizational justice and then deployed the organizational citizenship. Key words: organizational justice, organizational citizenship behavior, Jordan Press Organizations

    Collagen-calcium alginate film dressing with therapeutic ultrasound to treat open wound in rats

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    About 24 healthy female Sprague-Dawley rats weighing between 300-350 g were used in this study over a 20 day period. They were allocated randomly into 4 groups of 6 animals each. After the creation of 2x2 cm open wound, group 1 was control treated with Gentamycin ointment. Groups 2-4 were treated with Therapeutic ultrasound massage, collagen-calcium alginate film and collagen-calcium alginate film with therapeutic ultrasound. On application, the collagen-calcium alginate film with therapeutic ultrasound was well accepted by the animals without any adverse reaction. Mean percentage of wound contraction were significantly better in group 4 (p<0.05). Faster epithelialization was also seen in the collagen-calcium alginate film with therapeutic ultrasound treated group as compared to the other groups. Collagen is a biocompatible protein that does not interfere with the body’s normal immunologic response and can be used in non-healing chronic wounds which require a trigger to stimulate the normal healing process. In extensive wounds when there is lack of autologous tissue, biomaterials like collagen-calcium alginate may be beneficial and can be used

    Eurasian and African mitochondrial DNA influences in the Saudi Arabian population

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    BACKGROUND: Genetic studies of the Arabian Peninsula are scarce even though the region was the center of ancient trade routes and empires and may have been the southern corridor for the earliest human migration from Africa to Asia. A total of 120 mtDNA Saudi Arab lineages were analyzed for HVSI/II sequences and for haplogroup confirmatory coding diagnostic positions. A phylogeny of the most abundant haplogroup (preHV)1 (R0a) was constructed based on 13 whole mtDNA genomes. RESULTS: The Saudi Arabian group showed greatest similarity to other Arabian Peninsula populations (Bedouin from the Negev desert and Yemeni) and to Levantine populations. Nearly all the main western Asia haplogroups were detected in the Saudi sample, including the rare U9 clade. Saudi Arabs had only a minority sub-Saharan Africa component (7%), similar to the specific North-African contribution (5%). In addition, a small Indian influence (3%) was also detected. CONCLUSION: The majority of the Saudi-Arab mitochondrial DNA lineages (85%) have a western Asia provenance. Although the still large confidence intervals, the coalescence and phylogeography of (preHV)1 haplogroup (accounting for 18 % of Saudi Arabian lineages) matches a Neolithic expansion in Saudi Arabia

    Preparation of superhydrophobic and self-cleaning polysulfone non-wovens by electrospinning: influence of process parameters on morphology and hydrophobicity

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    Electrospinning is used to prepare hydrophobic and self-cleaning polysulfone (PSf) surfaces. The effects of PSf concentration in Dimethylformamide (DMF) solvent and electrospinning process parameters on the surface structure and hydrophobicity are investigated. The experimental results show that depending on PSf concentration, three types of morphologies are obtained: beads, beads-on-strings, and free-beads fibers. The surface hydrophobicity depends mainly on the resultant surface morphology, and the existence of beads increases hydrophobicity. The contact angle (CA) is found to increase from 73° for smooth PSf surface to more than 160° for surfaces formed by electrospinning. Moreover, the contact angle hysteresis (CAH) was generally less than 10° for all the chemistries. It is noted that increasing the PSf concentration leads to the formation of beads-on-string and free-beads fiber structures; this morphological change is accompanied by a reduction in the contact angle. Surface structures are found to be more sensitive to electrospinning feed rate than to electrospinning voltage; however, these two parameters have a negligible influence on the hydrophobicity. Porosity measurements of different chemistries show an average pore size in the range 3–8 microns. The thickness of PSf mats was variable, from as low as 10 μm to as high as 70 μm.King Fahd University of Petroleum and Minerals (KFUPM-MIT Project No. R16-DMN-11)King Abdulaziz City of Science and Technology (Saudia Arabia) (Project No. 11-ADV2134- 04

    A patient with typical clinical features of mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) but without an obvious genetic cause: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>There are currently 23 missense point mutations and one 4 basepair deletion spanning different mitochondrial genes associated with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS). The spectrum of mitochondrial DNA mutations in Arab patients with MELAS is largely unknown.</p> <p>Case presentation</p> <p>A standard clinical examination was carried out on a 34-year-old Saudi woman showing clinical features of MELAS. Fresh frozen muscle tissue was subjected to enzyme histochemical analysis. DNA was extracted from her leukocytes and muscle tissue, and the full mitochondrial genome was screened for base substitution mutations and deletions. Additionally, we screened the polymerase gamma-1 nuclear gene for mutations. The patient was negative for the most common m.3243 A>G MELAS mutation. Sequencing the full mitochondrial genome did not reveal any known or potentially pathogenic sequence changes. The polymerase gamma-1 gene was also free from mutations.</p> <p>Conclusion</p> <p>The clinical picture described here typically fits that observed in patients with MELAS or mitochondrial stroke-like events, but mutations in recognized genes (mitochondrial DNA and polymerase gamma-1 gene) were absent. We report the case of a patient with typical clinical features of MELAS, but without an obvious genetic cause.</p
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