An Exploratory Study of the Obstacles for Achieving Quality in Distance Learning during the COVID-19 Pandemic

This study aims to reveal the obstacles to achieving quality in distance learning during the Coronavirus (COVID-19) pandemic and was based on a large sample of professors and students of universities in the Arab world (Algerian, Egyptian, Palestinian, and Iraqi). The primary aim of this research was to investigate the various ways in which students pursued their studies at home during the university suspension as a result of COVID-19. In this paper, the researchers use an exploratory descriptive approach through a questionnaire with a conveniently selected sample of 400 professors and student’s returns out of 600 were distributed. The results indicate that the professors and students faced self-imposed obstacles, as well as pedagogical, technical, and financial or organizational obstacles. Recommendations are presented to overcome and understand these obstacles to benefit in the future during unexpected or similar problems

Obstacle Comparisons to Achieving Distance Learning and Applying Electronic Exams during COVID-19 Pandemic

This study aims to identify obstacles and barriers to achieving quality distance learning and the use of electronic exams, comparing them to pursue success in the distance education system during the coronavirus pandemic (COVID-19). It also aimed to determine the similarity and differences between the two main components of distance education. This is based on a sample of evaluations from professors and students at universities in the Arab world, i.e., Algerian, Egyptian, Iraqi, and Palestinian universities. We used a descriptive approach using questionnaires (open question) with conveniently selected samples from two different groups: (1) 400 professors and student’s feedback from 600 distributed (i.e., Algerian, Egyptian, Palestinian, and Iraqi) and (2) 152 professors and student’s feedback from 300 distributed (i.e., Palestinian universities in the governorates of Gaza). The results indicated that professors and students faced 27 barriers in both distance learning and electronic exams, which are divided into four groups (categories) according to the sample. Recommendations to understand and overcome these obstacles will also be presented to improve distance learning and e-exams in the future. It is important to coordinate efforts in the development of distance education, especially concerning universities using distance learning and e-exams

Phosphate-Based Organic-Inorganic Hybrid Materials: Design, Construction and Technological Applications

The art of designing and synthesizing organic molecules has reached very high levels of sophistication, based on a relatively simple set of rules that guide both the invention and synthesis of new compounds. This set of rules is construed as the rational synthetic method of organic chemistry. As material chemists confronted to the task of building new solid structures with tailored chemical properties, we do inevitably need to develop some rational approach and to establish the corresponding set of rules allowing a realistic level of predictive knowledge in the construction of solid scaffolds. These conditions are reasonably accomplished by the use of layered salts of tetravalent transition metals, namely zirconium phosphate (ZrP). The placing of organic molecules between the layers of ZrP is quite straightforward, can easily be controlled and leads to enduring, solid materials where the confinement makes the organic molecules to show new properties at the supramolecular level. The chemistry of metal phosphates/phosphonates will be detailed in relation with the following topics: (i) molecular recognition, (ii) chemically driven porosity changes, (iii) chiral memory and supramolecular chirality, (iv) luminescence signalling, (v) photo-induced electron-transfer processes, (vi) hydrogen storage, (vii) confinement of drugs and (viii) metal uptake

The understanding of Parkinson's disease through genetics and new therapies

Introduction: Parkinson's disease is one of the progressive neurodegenerative diseases from which people suffer for years. The mechanism of this disease is associated with a decrease in the number of dopaminergic neurons in the substantia nigra (SN) while Lewy bodies are still present. As a result, both motor-ridity, tremor, and bradykinesia-and non-motor symptoms such as anxiety and depression. Nowadays, it is well known that the cause behind Parkinson's disease is mainly environmental changes, genetic susceptibility, and toxins. Unfortunately, there is no cure for the disease but treatments. The replacement of lost neurons, alpha-synuclein and apomorphine, is currently being studied for new therapies. This article focuses on history, mechanism, factors causing Parkinson's disease as well as future therapies for the cure of the diseases. Methodology: Data were collected from medical journals published on PubMed, The Lancet, Cells, and Nature Reviews Neurology databases with a predefined search strategy. All articles considering new therapies for Parkinson's disease were considered. Results: The pathophysiology of Parkinson's disease is currently reasonably understood. However, there is no definitive cure so all the treatments focus mainly on reducing or limiting the symptoms. Current treatment studies focus on genetics, replacing lost neurons, alpha-synuclein and apomorphine. Conclusion: Parkinson's disease is the most common movement disorder worldwide because of the loss of dopaminergic neurons in the substantia nigra. Its symptoms include motor dysfunctions such as rigidity, tremor, and bradykinesia and non-motor dysfunctions such as anxiety and depression. Through genetics, environmental changes and toxins analysis, it is now known that future new therapies are working on replacing lost neurons, alpha-synuclein and apomorphine

The role of bacteria and mycorrhiza in plant sulfur supply

peer-reviewedPlant growth is highly dependent on bacteria, saprophytic, and mycorrhizal fungi which facilitate the cycling and mobilization of nutrients. Over 95% of the sulfur (S) in soil is present in an organic form. Sulfate-esters and sulfonates, the major forms of organo-S in soils, arise through deposition of biological material and are transformed through subsequent humification. Fungi and bacteria release S from sulfate-esters using sulfatases, however, release of S from sulfonates is catalyzed by a bacterial multi-component mono-oxygenase system. The asfA gene is used as a key marker in this desulfonation process to study sulfonatase activity in soil bacteria identified as Variovorax, Polaromonas, Acidovorax, and Rhodococcus. The rhizosphere is regarded as a hot spot for microbial activity and recent studies indicate that this is also the case for the mycorrhizosphere where bacteria may attach to the fungal hyphae capable of mobilizing organo-S. While current evidence is not showing sulfatase and sulfonatase activity in arbuscular mycorrhiza, their effect on the expression of plant host sulfate transporters is documented. A revision of the role of bacteria, fungi and the interactions between soil bacteria and mycorrhiza in plant S supply was conducted

Variation in Molybdenum Content Across Broadly Distributed Populations of Arabidopsis thaliana Is Controlled by a Mitochondrial Molybdenum Transporter (MOT1)

Molybdenum (Mo) is an essential micronutrient for plants, serving as a cofactor for enzymes involved in nitrate assimilation, sulfite detoxification, abscisic acid biosynthesis, and purine degradation. Here we show that natural variation in shoot Mo content across 92 Arabidopsis thaliana accessions is controlled by variation in a mitochondrially localized transporter (Molybdenum Transporter 1 - MOT1) that belongs to the sulfate transporter superfamily. A deletion in the MOT1 promoter is strongly associated with low shoot Mo, occurring in seven of the accessions with the lowest shoot content of Mo. Consistent with the low Mo phenotype, MOT1 expression in low Mo accessions is reduced. Reciprocal grafting experiments demonstrate that the roots of Ler-0 are responsible for the low Mo accumulation in shoot, and GUS localization demonstrates that MOT1 is expressed strongly in the roots. MOT1 contains an N-terminal mitochondrial targeting sequence and expression of MOT1 tagged with GFP in protoplasts and transgenic plants, establishing the mitochondrial localization of this protein. Furthermore, expression of MOT1 specifically enhances Mo accumulation in yeast by 5-fold, consistent with MOT1 functioning as a molybdate transporter. This work provides the first molecular insight into the processes that regulate Mo accumulation in plants and shows that novel loci can be detected by association mapping

A NEW FRAMEWORK FOR PREDICTING THE IMPACT OF TRAFFIC ON THE PERFORMANCE OF MOBILE AD-HOC NETWORK (MANET): USING REGRESSION AS DATA MINING APPROACH

With the rapid technological advances in wireless communication and the increasing of usage of portable computing devices, it is expected that mobile ad hoc networks are increasingly developed towards enhancing the flexibility, scalability and efficiency of communication technology. The wireless ad-hoc network is a collection of mobile nodes in which these nodes have the ability to connect each other without backbone infrastructure (i.e. infrastructure less). Although many studies have been done on the performance assessment of MANET routing protocols, there is a need for investigating the impact of traffic load on the performance of MANET in order to justify the use of some routing protocol in MANET. This study is one of the fewest that aims at proposing a new framework towards predicting and validating the results of future scenario using data mining techniques. The regression analysis is used as data mining method in the prediction of the future scenarios. Practically, two experiments with eight scenarios are conducted. The findings indicate that the network size and traffic loads are proportionally related to the throughput. However, the findings show that the network size is inversely related to the delay in case of medium FTP traffic, and proportionally related in case of high FTP traffic. The results also indicate that data mining approach specially regression is an effective approach towards the prediction of the future network behavior