An evaluation of the Arabic error tagset v2

A survey of the literature shows that annotating errors of Arabic learners has not received much attention, and there is a need for a practical error tagset which can be used for Arabic learner corpora. This type of tagset is used in such corpora for several purposes, e.g., Contrastive Interlanguage Analysis (CIA), learner dictionary making, Second Language Acquisition, designing pedagogical materials, etc. This paper evaluates the second version of a two-level error tagset developed for annotating the Arabic Learner Corpus (ALC). It includes six broad classes, subdivided into more specific error types. The paper shows the tagset, and an example of the annotation method used for tagging the ALC. The inter-annotator agreement using the current revised version of the error tagset was higher compared to the first version (Alfaifi et al., 2013). Four factors assisted in reaching this level of accuracy: (1) the tagset was reviewed by two experts in Arabic language, (2) the annotators were given texts with errors already identified, so the ir task was to classify and mark the appropriate tag on each error, (3) the annotators were trained during the experiment, (4) an error tagging manual was created which explains all error types in the tagset with rules and examples of how to tag learners' errors. Two lists of varied sentences, 100 in each, were tagged for errors by three annotators; after tagging the first list they discussed their work to provide them with suitable training, and this allowed us to distinguish the value of the training among the other factors

Nicotine metal complexes: synthesis, characterization and bioactivities of some main group and some transition metals

A number of some main group and transition metal nicotine complexes were synthesized and fully characterized using detailed structural and spectroscopic analysis techniques such as elemental analysis, molar conductivities, magnetic susceptibilities, IR, Raman and NMR techniques. Moreover, scanning electron micrographs and thermogravimetric analyses were also done. Cytotoxic activities of the binary nicotine metal complexes were tested and evaluated against HepG2 (human hepatocellular carcinoma), HPC3 (human prostate cancer), and HCT116 (human colorectal carcinoma) tumor cell lines. The antioxidant activities were examined by free radical scavenging assay. The antimicrobial activities of the synthesized complexes were evaluated against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) microbes. The relationship between the chemical structure of the synthesized complexes and their biological influence as antimicrobial drugs was studied and evaluated.                     KEY WORDS: Nicotine metal complexes, Cytotoxicity, Antioxidant, Antimicrobial   Bull. Chem. Soc. Ethiop. 2020, 34(3), 501-521. DOI: https://dx.doi.org/10.4314/bcse.v34i3.

A cross-sectional assessment of health-related quality of life among healthcare providers in Alkharj, Saudi Arabia

Purpose: To determine the current level of health-related quality of life (HRQoL), and evaluate factors influencing it among health-care providers (HCPs) in Alkharj, Saudi Arabia.Methods: A prospective cross-sectional study was conducted among HCPs in Alkharj, Saudi Arabia, using the standardized research tool, BREF-WHOQOL. A self-administered questionnaire was distributed in hospitals, in the medical colleges of Prince Sattam Bin Abdulaziz University, andcommunity pharmacies in Alkharj, Saudi Arabia. Descriptive, comparative, and inferential statistics were performed using SPSS.Results: A total of 289 HCPs agreed to participate in the study, 52 % of whom were female. Most participants were married (69 %), and most had fewer than 10 years of experience (58 %). Statistically significant differences in marital status, education level, income, and year of practice were found that correlated with HCPs’ HRQoL (p ≤ 0.05). Overall, respondents reported an above-average score for all survey items.Conclusion: The results indicate that HCPs see their general quality of life as good - a particularly important consideration in view of the demanding nature of their job. This study will help the concerned authorities to exactly know the current level of HRQoL among HCPs in Alkharj, Saudi Arabia, as well as help in designing better healthcare policies in Saudi Arabia. Keywords: Healthcare providers (HCP), Health-related quality of life (HRQoL), Healthcare policies, Occupational stres

Radical scavenging activity of some natural tropolones by density functional theory

The ground state neutral geometries of some natural tropolones, i.e. stipitatonic acid (AF1), stipitalide (AF2), stipitaldehydic acid (AF3) and methyl stipitate (AF4) have been optimized by using Density Functional Theory (DFT) at B3LYP/6-31G*, B3LYP/6-31G**, B3LYP/6-31+G* and B3LYP/6-31+G** levels of theory. The excited state geometries of AF1-AF4 were optimized by adopting the Time Dependent Density Functional Theory (TDDFT) at the same levels of theory. The frequencies and cation species of AF1-AF4 were also computed at all the above mentioned levels of theory. We shed light on the electro-optical and molecular properties, e.g. energy gaps, highest occupied molecular orbitals, lowest unoccupied molecular orbitals, absorption wavelengths, electronegativity (χ), hardness (η), electrophilicity (ω), softness (S), electrophilicity index (ωi) and the radical scavenging activity (RSA). Hydrogen atom transfer (HAT) and one-electron transfer mechanisms have been discussed to shed light on the RSA. The smallest ionization potential and bond dissociation energy of AF4 are revealing that this compound would have more RSA than those of other counterparts

Recent Advancements in GaN LED Technology

Gallium nitride (GaN)-based solid state lighting technology has revolutionized the semiconductor industry. The GaN technology has played a crucial role in reducing world energy demand as well as reducing the carbon footprint. As per the reports, the global demand for lighting has reduced around 13% of total energy consumption in 2018. The Department of Energy (USA) has estimated that bright white LED source could reduce their energy consumption for lighting by 29% by 2025. Most of the GaN LEDs are grown in c-direction, and this direction gives high growth rate and good crystal integrity. On the other hand, the c-plane growth induces piezoelectric polarization, which reduces the overall efficiency of LEDs since the last decade researchers round the globe working on III-N material to improve the existing technology and to push the limit of III-V domain. Now, the non-polar and semi-polar grown LEDs are under investigation for improved efficiency. With the recent development, the GaN is not only limited to lighting, but latest innovations also led the development of micro-LEDs, lasers projection and point source. These developments have pushed GaN into the realm of display technology. The miniaturization of the GaN-based micro-LED and integration of GaN on silicon driving the application into fast response photonic integrated circuits (ICs). Most of the recent advancements in GaN LED field would be discussed in detail

Preparation and characterization of quinoxaline-pyrene-based conjugated copolymers for organic photovoltaic devices

In this study, two novel conjugated polymers, poly(4,5,9,10-tetrakis((2-ethylhexyl)oxy]pyrene-alt-2,3-bis(3-(octyloxy)phenyl)-5,8-di(2-thienyl)-6,7-difluoroquinoxaline) (PPyQxff) and poly(4,5,9,10-tetrakis((2-ethylhexyl)oxy)pyren-alt-2,3-bis(3-(octyloxy)phenyl)-5,8-di(2-thienyl)quinoxaline) (PPyQx), consisting of quinoxaline units with and without fluorine substituents, as electron-accepting moieties and pyrene flanked with dithienyl units as electron-donating moieties were prepared via Stille polymerization reactions for use as electron donor materials in bulk heterojunction (BHJ) solar cells. PPyQxff and PPyQx were characterized by X-ray powder diffraction (XRD), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), cyclic voltammetry (CV), UV−VIS absorption, and nuclear magnetic resonance (NMR) spectroscopy. PPyQxff and PPyQx revealed excellent solution processability in common organic solvents. PPyQxff and PPyQx presented decomposition temperatures above 300 °C. The inclusion of F atoms to the quinoxaline moiety made a slight reduction in the highest occupied molecular orbital (HOMO) level, relative to the unfluorinated polymer, but had no impact on the lowest unoccupied molecular orbital (LUMO) level. PPyQxff and PPyQx exhibited similar physical properties with strong and broad absorbance from 400 to 700 nm and an optical band-gap energy of 1.77 eV. The X-ray powder diffraction study indicated that PPyQxff possessed a reduced π–π stacking distance relative to PPyQx

Diagnostic Imaging and Radiation Therapy in the Arab World: A New Model of Advanced Practice

This study aimed at suggesting a new model for advanced practice in the diagnostic imaging and radiation therapy in the Arab World by presenting a comparative study between the different medical imaging techniques, the concepts, benefits, risks and medical applications of these techniques has been presented with details. Attempting For building a new model of advanced practice for the diagnostic role of  imaging and radiation therapy in the Arab World; by analyzing the current status of the imaging and radiation therapy in the Arab World, and then surveying the different medical imaging techniques. Then  to suggest a model of best practices upon the outcomes of the study

Cold-Active Enzymes and Their Potential Industrial Applications—A Review

More than 70% of our planet is covered by extremely cold environments, nourishing a broad diversity of microbial life. Temperature is the most significant parameter that plays a key role in the distribution of microorganisms on our planet. Psychrophilic microorganisms are the most prominent inhabitants of the cold ecosystems, and they possess potential cold-active enzymes with diverse uses in the research and commercial sectors. Psychrophiles are modified to nurture, replicate, and retain their active metabolic activities in low temperatures. Their enzymes possess characteristics of maximal activity at low to adequate temperatures; this feature makes them more appealing and attractive in biotechnology. The high enzymatic activity of psychrozymes at low temperatures implies an important feature for energy saving. These enzymes have proven more advantageous than their mesophilic and thermophilic counterparts. Therefore, it is very important to explore the efficiency and utility of different psychrozymes in food processing, pharmaceuticals, brewing, bioremediation, and molecular biology. In this review, we focused on the properties of cold-active enzymes and their diverse uses in different industries and research areas. This review will provide insight into the areas and characteristics to be improved in cold-active enzymes so that potential and desired enzymes can be made available for commercial purposes

Cold-Active Enzymes and Their Potential Industrial Applications—A Review

More than 70% of our planet is covered by extremely cold environments, nourishing a broad diversity of microbial life. Temperature is the most significant parameter that plays a key role in the distribution of microorganisms on our planet. Psychrophilic microorganisms are the most prominent inhabitants of the cold ecosystems, and they possess potential cold-active enzymes with diverse uses in the research and commercial sectors. Psychrophiles are modified to nurture, replicate, and retain their active metabolic activities in low temperatures. Their enzymes possess characteristics of maximal activity at low to adequate temperatures; this feature makes them more appealing and attractive in biotechnology. The high enzymatic activity of psychrozymes at low temperatures implies an important feature for energy saving. These enzymes have proven more advantageous than their mesophilic and thermophilic counterparts. Therefore, it is very important to explore the efficiency and utility of different psychrozymes in food processing, pharmaceuticals, brewing, bioremediation, and molecular biology. In this review, we focused on the properties of cold-active enzymes and their diverse uses in different industries and research areas. This review will provide insight into the areas and characteristics to be improved in cold-active enzymes so that potential and desired enzymes can be made available for commercial purposes