Dhofar University
  • Şalālah, Dhofar, Oman
Recent publications
The present study aimed to investigate the relationship between corruption control, government effectiveness and banking stability in 21 countries during the period of 2003–2019. The study used many estimators to overcome heterogeneity and endogeneity issues as well as diagnostic tests to increase robustness. The unit root test results showed that all variables were stationary. The Pedroni, Kao and Westerlund cointegration test results supported the rejection of the null hypothesis of no cointegration, confirming the long-run effects of corruption control and government effectiveness on banking stability. In addition, FMOLS and DOLS were used to control endogeneity. The dynamic panel data estimator results revealed a significant negative relationship between corruption control, government effectiveness and banking stability in high-income countries. The low-income country results indicated that the opposite scenario was true for most estimations. The middle- and high-income country results were the same for the corruption control, government effectiveness and banking stability nexus but different for government effectiveness and banking stability. The main conclusions of the study were that countries with high corruption control enhance banking stability growth by employing the grease the wheels hypothesis under high levels of government effectiveness and countries with low corruption control impede banking stability growth by applying the sands the wheels hypothesis under low levels of government effectiveness.
The study uses wavelet power spectrum and wavelet coherence transformation methodologies to examine how geopolitical risk affected the returns on stocks, oil, and gold during the GFC, COVID-19, and Russia-Ukraine war-three disruptive events that affected the world’s financial markets. For better diversification benefits during the turbulent times, we further investigate the degree of co-movement in frequency and time domains. We observe that GPR has high variations during Russia-Ukraine war period compared to COVID-19 period and is shown to have least variation during the GFC period. WTI crude oil and DJGI indexes are observed to have high variations during GFC, and COVID-19 periods followed by Russia-Ukraine war. We further observe that GOLD offers better diversification opportunity as well as leading movement against WTI and DJGI during disruptive events in financial markets. The results provide new understanding of how geopolitical risk affects financial assets for international investors, fund managers, and regulators, which would further aid to find risky and safer haven possibilities during the turmoil periods.
Diabetes management is a challenging task and accurate glucose sensing remains a crucial yet elusive goal. Herein, we demonstrated the capacity of electrochemically-active non-enzymatic glucose sensing of nanoporous CuO/Ag and nanoflower shaped CuO/Ag/SiNPs in an alkaline environment. The crystalline structure and the surface morphology of nanoporous CuO/Ag, and nanoflower shaped CuO/Ag/SiNPs-based composite materials were analyzed using powder X-ray diffraction (P-XRD), energy dispersive X-ray (EDX) spectroscopy, X-ray Photoelectron spectra (XPS), Raman Spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The electro-catalytic characteristics of the fabricated electrode materials for glucose electro-oxidation in alkaline circumstances were examined using the cyclic voltammetry (CV) and chronoamperometry methods. The FGGS (Fourth Generation Glucose Sensors) from the composite materials exhibited a remarkable performance for glucose sensing with a wide linear range of 0.001 to 10 mM and 0.1 to 2.5 µM, an ultrahigh sensitivity of 4877.6 μA mM ⁻¹ cm ⁻² , and a low detection limit (0.1μM). The designed electrode responded positively to the addition of glucose electro-oxidation and reached steady-state within 0.4 seconds with reproducibility (above 3000 cycles) and the diffusion rate constant for this electrochemical Nanoflower shaped CuO/Ag/SiNPs-based sensor is 0.6 cm/s. The nanoporous composite materials are cost-effective and possess improved sensitivity, selectivity, and response time, thus making them suitable for the fabrication of glucometers. The use of such materials will be beneficial for the diagnosis and treatment of hyperglycemia, as well as for the development of implantable glucose sensors and wearable sensors.
Investment intensity is the level of investment in fixed assets that affects a company’s long-term growth prospects. In order to make good investment decisions, investors pay more attention to achieving a high level of investment intensity. This study examines the impact of two non-GAAP measures of profitability—earnings before interest, tax, depreciation, and amortization and earnings before interest and tax—on investment intensity in Gulf Cooperation Council (GCC) member countries. The study also examines the preference for two non-GAAP measures of profitability from the perspective of foreign investors. The study conducts panel data regressions using 205 firm observations covering the period 2010–2019 to examine the relationship between earnings before interest, tax, depreciation and amortization, earnings before interest and tax, and investment intensity. The study used various statistical estimators to overcome the heterogeneity and endogeneity problems of panel data and employed many diagnostic tests to increase robustness. The study finds that earnings before interest, tax, depreciation and amortization are positively and significantly associated with investment intensity in all GCC countries, but earnings before interest and tax are negatively associated with investment intensity in these countries. The results indicate that foreign investors prefer to use earnings before interest, tax, depreciation, and amortization to make decisions about investment intensity. The main implication of the study is that capital market regulators and foreign investors should use earnings before interest, tax, depreciation, and amortization information as a guideline to improve investment intensity decisions and achieve a better allocation of resources in capital markets.
There is a debate around the world about the role of higher education institutions in emerging economies in producing employable graduates. With the industry's ever-changing requirements, do the graduates have the required knowledge, skills, values, attributes, and competency to cope with the job's requirements? Are the students able to contribute positively to the organization they work for? This paper examines the perceived effects of graduate business education in attaining personal and professional development like leadership skills, managerial capabilities, increase in salary, job status, job change, and overall standard of living of graduates. This study aims to understand the impact of graduate business education on graduates’ careers. Career impact is measured in terms of change in leadership positions, increase in salary, job status, job change, and standard of living. The study’s implication is to understand the expected unexpected industry accordingly, bring changes in the curriculum, and assist business schools in taking initiatives to increase the employability of graduates.
Due to the benefits of e-portfolio assessment and summative assessment in Ethiopia and a dearth of research, this study attempted to contrast e-portfolio assessment and summative assessment use in developing Ethiopian EFL learners’ writing complexity, accuracy, and fluency (CAF); learners’ autonomy; learning anxiety; and self-efficacy as they have not been investigated in Ethiopia. In order to accomplish these goals, 60 Ethiopian intermediate EFL students were selected according to their OQPT performance. E-portfolio served as the experimental group (EG), and summative functioned as the control group (CG). Writing CAF, self-efficacy, autonomy, and anxiety pretests were administered to both groups. Then, groups received different treatments. Writing CAF, self-efficacy, autonomy, and anxiety posttests were then given to the groups after the instruction period of 21 sessions. The collected data were examined using SPSS software. Then, independent samples t-tests and paired samples t-tests were run to assess the effects of the assessments on the learners’ writing CAF, autonomy, anxiety, and self-efficacy. The outcomes displayed that the experimental group and control group differed in performance. Actually, the e-portfolio assessment group outdid the summative assessment group. The eportfolio assessment was found to be a more useful method for fostering learner autonomy, self-efficacy, and the writing CAF in EFL learners than summative assessment. Some recommendations, implications, and limitations were also listed at the end.
Hydrogels are applied in biomedical fields, especially in sustained drug release studies. However, improvements in their material properties are always needed to make them suitable for their potential biomedical use. Herein, a core–shell particles latex (CS) made of poly(2-acrylamido-2-methylpropane sulfonic acid)@butyl methacrylate anchored into polyethylene glycol diacrylate (PEGDA) matrix-based composite hydrogel (PEG-CS) was prepared through multiple steps free radical polymerization. The fabricated PEG-CS hydrogel was used for the loading and controlled release of ciprofloxacin as a model drug at various experimental conditions. An optimum drug concentration of 30 ppm at a loading efficiency of up to 660 mg/g for PEG-CS hydrogel was obtained after 8 h of adsorption, which was much higher than using only PEGDA-based hydrogel (control). The kinetic models and equilibrium isotherms of adsorption showed that the drug loading followed pseudo-second-order kinetics and the Langmuir adsorption isotherm, respectively. The drug demonstrated a sustained release at 37 °C and pH 7.4, at which 80% of the drug was released after 24 h. The Peppas equation gave “n” values of 0.50–0.60, indicating the drug release mechanism was governed by diffusion and erosion processes. The findings of this study show that the fabricated PEG-CS could be an efficient potential material for sustained drug release. Graphical Abstract
This study aims to explore Saudi students’ entrepreneurial orientation (EO) toward e-businesses in the line of achieving the strategic objectives of Saudi Vision 2030. Saudi Vision 2030 (hereafter, Vision 2030) is a strategic framework to attain the sustainable development of Saudi Arabia. It was first announced by Crown Prince Mohammad bin Salman in April 2016. Authors have proposed a Saudi Vision Linkages Model to show the role and importance of university education (UE) and entrepreneurial culture in fulfilling the specific requirements of the Saudi labor market to attain the ultimate strategic objectives of Vision 2030. The authors also proposed a conceptual model of the study to depict the relationships of EO with their entrepreneurial intention toward online businesses (e-EI). The study used a multidimensional model of the EO where three subdimensions, namely risk-taking propensities (RTP), innovativeness (INV), and pro-activeness (P-ACT), are used. The conceptual model of the study also shows UE and gender (GEN) as moderating variables. The authors used convenience sampling to collect cross-sectional data and conducted an online survey among the students at Saudi Electronic University (SEU) using a 5-point Likert-type scale to collect the data through a questionnaire, observing a total of 17 items and 408 filled questionnaires were received. Authors proposed six hypotheses where four hypotheses build the direct relations, namely, RTP (H1), INV (H2), P-ACT (H3), and UE (H4) with e-EI and hypotheses H5 and H6 are further divided into the subhypotheses, respectively, in H5a, H5b, H5c and H6a, H6b, H6c to show the moderating effect of UE (H5) and GEN (H6). SmartPLS 4.0 software is used to apply structural equation modeling for the analysis of data. Reliability, composite validity, discriminant validity, and model-fit indices of the measurement model are assessed before running a bootstrapping to measure the significance and standardized β estimates of the paths of hypotheses (structural model analysis). After analyzing the results, in the suggestions section, the authors have suggested that the university build a university business incubator for the students to promote entrepreneurial activities on all the campuses with a head office in the Riyadh campus.
Cancer drug resistance remains a major obstacle in clinical oncology. As most anticancer drugs are of natural origin, we investigated the anticancer potential of a standardized cold-water leaf extract from Nerium oleander L., termed Breastin. The phytochemical characterization by nuclear magnetic resonance spectroscopy (NMR) and low- and high-resolution mass spectrometry revealed several monoglycosidic cardenolides as major constituents (adynerin, neritaloside, odoroside A, odoroside H, oleandrin, and vanderoside). Breastin inhibited the growth of 14 cell lines from hematopoietic tumors and 5 of 6 carcinomas. Remarkably, the cellular responsiveness of odoroside H and neritaloside was not correlated with all other classical drug resistance mechanisms, i.e., ATP-binding cassette transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS), tumor suppressors (TP53, WT1), and others (GSTP1, HSP90, proliferation rate), in 59 tumor cell lines of the National Cancer Institute (NCI, USA), indicating that Breastin may indeed bypass drug resistance. COMPARE analyses with 153 anticancer agents in 74 tumor cell lines of the Oncotest panel revealed frequent correlations of Breastin with mitosis-inhibiting drugs. Using tubulin-GFP-transfected U2OS cells and confocal microscopy, it was found that the microtubule-disturbing effect of Breastin was comparable to that of the tubulin-depolymerizing drug paclitaxel. This result was verified by a tubulin polymerization assay in vitro and molecular docking in silico. Proteome profiling of 3171 proteins in the NCI panel revealed protein subsets whose expression significantly correlated with cellular responsiveness to odoroside H and neritaloside, indicating that protein expression profiles can be identified to predict the sensitivity or resistance of tumor cells to Breastin constituents. Breastin moderately inhibited breast cancer xenograft tumors in vivo. Remarkably, in contrast to what was observed with paclitaxel monotherapy, the combination of paclitaxel and Breastin prevented tumor relapse, indicating Breastin’s potential for drug combination regimens.
Today, network communication holds a crucial importance of all other types of networks. Of all the advanced network structures, distributed networking system has huge demand. Smart dust network which is one of the categories of distributed networks is the future of distributed networks and has its applications in crucial fields. It is envisioned to blend the features such as ability to sense, compute, and communicate wirelessly. These micro devices can be sprinkled to form a dense network that can monitor real-life processes with high precision results. In this work, we present the characteristics, applications and possibility of using artificial technologies in Smart Dust networks.
In the empirical literature, few studies assessed the influence of the insurance market on carbon emissions. However, the effects of insurance markets on the load capacity factor (LCF) have been ignored. In this regard, the objective of the current work is to assess the potential impact of the insurance market on environmental sustainability in 27 OECD countries from 1990 to 2018 based on the LCF, which implies the strength of a state to enhance the population based on the current lifestyle. The present work employed the novel Method of Moments Quantile Regression (MMQR). This model is the prime and correct technique to better understand the association between the insurance market and the LCF across heterogeneous quantiles and to yield more robust empirical outcomes. The MMQR findings indicate a negative interaction between the insurance market and the LCF. In other words, the insurance sector has a powerful influence on economic activities and investments, such that insurance activities lead to an increase in the level of energy utilization, and thus have a negative influence on ecological sustainability. In contrast, the findings illustrate a positive and considerable association between renewable energy consumption and LCF. Based on the overall outcomes, it is suggested that OECD countries should focus on policies that encourage the use of renewable energy rather than incentivizing the insurance market. OECD country governments should also support green insurance activities to minimize the environmental damage of the insurance market.
A hybrid machine learning method is proposed for wildfire susceptibility mapping. For modeling a geographical information system (GIS) database including 11 influencing factors and 262 fire locations from 2013 to 2018 is used for developing an integrated multivariate adaptive regression splines (MARS). The cat swarm optimization (CSO) algorithm tunes the parameters of the MARS in order to generate accurate susceptibility maps. From the Pearson correlation results, it is observed that land use, temperature , and slope angle have strong correlation with the fire severity. The results demonstrate that the prediction capability of the MARS-CSO model outperforms model tree, reduced error pruning tree and MARS. The resulting wildfire risk map using MARS-CSO reveals that 20% of the study areas is categorized in the very low wildfire risk class, whereas 40% is under the very high class of fire hazard. ARTICLE HISTORY
Hierarchical nanostructures with appropriate morphology and surface functionalities are highly desired to achieve an optimized electrochemical property for active electrode materials. This work renders the facile hydrothermal synthesis of CdO, SnO2, and CdO-SnO2 nanocomposite, and their capacitive performance was tested. The formation of the pure samples and their composite was committed by low-temperature Raman spectroscopy and x-ray diffraction studies which revealed the tetragonal and cubic structures of CdO and SnO2 powder samples with good crystallinity and purity. The morphological postmortem reveals the formation of nanoparticles morphology of CdO with a highly smooth surface appearance. Besides, the SnO2 illustrates the morphology of the micro flowers composed of ultrathin nanosheets. More specifically, the electrochemical properties indicate the pseudocapacitive charge storage mechanism based on cyclic voltammetry and chronopotentiometry analysis. The CdO-SnO2 composite electrode displayed a higher capacitance due to additional pores/space offered for active sites and continuously allowed electrolyte ions to interact with the inner/outer surface of the electrode. These exciting findings led us to design and fabricate battery hybrid supercapacitors (BHSC) from CdO-SnO2, and activated carbon (AC), referred to as CdO-SnO2//AC BHSC, attains a high power delivery (5717 W/kg), and a maximum energy density of 42 Wh/kg at low discharge rate. Noteworthy, a stable cycling performance was obtained with only 91.3% retention after 8000 cycling at a large discharge current of 10 A/g, denoting the magnificent durability of the active electrode material.
The efficient planning, execution, and management of institutional frameworks for climate change adaptation are essential to sustainable development. India, in particular, is known to be disproportionately vulnerable to the consequences of climate change. This study examines the effects of environmental taxes, corruption, urbanization, economic growth, ecological risks, and renewable energy sources on CO2 emissions in India from 1978 to 2018. Therefore, the ARDL model is used to draw inferences, and Pairwise Granger causality is also applied to demonstrate a causeand- effect relationship. The empirical results show that corruption, environmental dangers, GDP, and urbanization positively influence India’s carbon emissions. However, the results of short-run elasticities show that carbon emissions reduce ecological sustainability. Environmental hazards and costs, like other countries, impact India’s carbon emissions. Therefore, decision-makers in India should set up strict environmental regulations and anti-corruption measures to combat unfair practice that distorts competition laws and policies. In addition, the government concentrates more on energy efficiency policies that diminish carbon emissions without hampering economic growth in the country.
In this research, the effect of heat-cool cycles (HCCs) on high-strength concrete (HSC) containing steel fibres (SFs), polypropylene fibres (PPFs), and date palm fibres (DPFs), which were named fibrous high-strength concrete (FHSC), was studied. To produce FHSC, three doses of 0.2, 0.6, and 1 percent of each fibre were used. All samples were tested after 28 days of normal water curing and 270 days of exposure to HCCs (continuing the authors' project and research published at 28 and 180 days). This entails heating for 2 days at 60 C in the oven and cooling for another 2 days at room temperature for 270 days. The experiment's findings revealed that fibre reinforcement in concrete enhances its strength and durability. By incorporating the three types of fibres into high-strength concrete, with and without HCCs, the modulus of rupture was significantly increased. In both conditions, including with or without the implementation of HCCs, incorporating the three fibre types into the HSC showed a significant increase in toughness. As a result, natural date palm fibres can produce sustainable FHSC that can withstand harsh environmental conditions. Moreover, compared to the previous study conducted by the authors at 180 days, there is a slight severity in both the pattern of decrease and increase of the studied characteristics at 270 days caused by the effect of thermal cycles and fibres.
Nanomaterials have been the focus of intensive development and research in the medical and industrial sectors over the past several decades. Some studies have found that these compounds can have a detrimental impact on living organisms, including their cellular components. Despite the obvious advantages of using nanomaterials in a wide range of applications, there is sometimes skepticism caused by the lack of substantial proof that evaluates potential toxicities. The interactions of nanoparticles (NPs) with cells of the immune system and their biomolecule pathways are an area of interest for researchers. It is possible to modify NPs so that they are not recognized by the immune system or so that they suppress or stimulate the immune system in a targeted manner. In this review, we look at the literature on nanomaterials for immunostimulation and immunosuppression and their impact on how changing the physicochemical features of the particles could alter their interactions with immune cells for the better or for the worse (immunotoxicity). We also look into whether the NPs have a unique or unexpected (but desired) effect on the immune system, and whether the surface grafting of polymers or surface coatings makes stealth nanomaterials that the immune system cannot find and get rid of.
This study was aimed to develop low-cost bacterial cellulose (BC)-based antibacterial composite with pomegranate (Punica granatum L.) peel extract (PGPE) for potential biomedical applications. BC was cost-effectively produced by utilizing food wastes, and PGPE was ex situ impregnated into its hydrogel. Field-emission scanning electron microscopic (FE-SEM) observation showed a nanofibrous and microporous morphology of pristine BC and confirmed the development of BC-PGPE composite. Fourier transform infrared (FTIR) spectroscopy indicated the chemical interaction of PGPE with BC nanofibers. BC-PGPE composite held 97 % water of its dry weight and retained it for more than 48 h. The BC-PGPE composite exhibited better reswelling capabilities than pristine BC after three consecutive re-wetting cycles. The antibacterial activity of the BC-PGPE composite was determined via minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), disc diffusion, and plate count methods. The PGPE extract showed good antimicrobial activity against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative), both in the form of extract and composite with BC, with relatively better activity against the former. The BC-PGPE composite produced a 17 mm zone of inhibition against S. aureus, while no inhibition zone was formed against E. coli. Furthermore, BC-PGPE composite caused a 100 % and 50 % reduction in the growth of S. aureus and E. coli, respectively. The findings of this study indicate that BC-PGPE composite could be a promising antibacterial wound dressing material.
In recent years, significant endeavors have been made to develop environmentally friendly fuels due to the detrimental effects of fossil fuels on ecosystem such as global warming, acid rain and air pollution. Alternative biodiesel transport fuel (ABTF) has shown their noteworthy potential of application due to having significant advantages such as negligible toxicity and excellent biodegradability. In this paper, Neural Network-based approaches were employed to create predictions in this work, including Multilayer Perceptron, Boosted Multilayer Perceptron, and Bagging Multilayer Perceptron. The regression issue has three input features: Reaction duration, catalyst amount, and methanol/oil ratio, and the only output is FAME yield. All three versions of these neural network models were tuned using their critical hyper-parameters and chose the optimal mix. Then, some standard measures are used to evaluate their performance. Multilayer perceptron, Boosted Multilayer perceptron, and Bagging Multilayer perceptron has error rates of 0.998, 0.998, and 0.877, respectively, and have MSE errors of 2.87, 1.19, and 5.57. Additionally, considering the MAPE 1.51E−02, 1.09E−02, and 2.26E−02 values acquired. Finally, the boosted multilayer perceptron is the most general and accurate model. Additionally, the optimal output value is 98.99 when the input vector is (x1=158, x2=1.25, x3=33.75).
Sometimes civil engineering infrastructures have been constructed in hot and cold weathering regions such as desert areas. In such situations, the concrete is not only smashed by hot and cold processes but also spoiled by shrinkage cracking. Therefore, this study intends to examine the influence of heat–cool cycles on high-strength concrete comprising various fibers, such as natural date palm, polypropylene, and steel fibers, and their different volume percentages. The most popular technique for improving the structural behavior of concrete is fiber insertion. Fibers decrease cracking occurrences, enhance early strength under impact loads, and increase a structure’s ability to absorb additional energy. The main goal is to examine the effects of three different types of fibers on regular concrete exposed to heat–cool cycles. For each type of fiber, three dosages of 0.2%, 0.6%, and 1% were used to create high-strength concrete. After 28 days of regular water curing and six months of exposure to heat-and-cold cycles, all specimens were tested. The heat–cool cycles entailed heating for two days at 60 °C in the oven and cooling for another two days at room temperature. The results of the experiment showed that fiber reinforcement in concrete improves its strength and durability. The flexural strength was substantially improved by increasing the date palm, polypropylene, and steel fibers into the high-strength concrete with and without heat–cool cycles. Adding increments of date palm, polypropylene, and steel fibers into high-strength concrete revealed a significant improvement in energy absorption capacity in both cases, i.e., with or without the implementation of heat–cool cycles. Therefore, the natural date palm fibers might be utilized to produce sustainable fibrous high-strength concrete and be applicable in severe weathering conditions.
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649 members
Sameen Ahmed Khan
  • Department of Mathematics and Sciences
Fatemeh Khozaei
  • College of Engineering (CE)
Luay Rashan
  • Biodiversity Research Center
Mohd Idrees
  • Department of Mathematics and Sciences
Ahmmed Saadi
  • Department of Chemical Engineering
Information
Address
PO Box 2509, 211, Şalālah, Dhofar, Oman
Head of institution
Prof. Hassan Kashoob
Website
www.du.edu.om
Phone
+968/23237006
Fax
+968/23237777