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We study the Goos–Hänchen shift (GHS) of a reflected light beam from a cavity containing a double-$$\Lambda$$ Λ atomic medium that is bounded by two glass slabs. Applying both coherent and incoherent fields to the atomic medium leads to positive and negative controllability of GHS. For some specific values of the parameters of the system, the amplitude of the GHS becomes large, namely, in the order of $$\sim 10^{3}$$ ∼ 10 3 times the wavelength of the incident light beam. These large shifts are found at more than one angle of incidence with a wide range of parameters of the atomic medium. more...

Rainfall thresholds are commonly utilized to forecast landslides using the historical relationship between occurrence of slope failures and rainfall in an area. SIGMA (Sistema Integrato Gestione Monitoraggion Allerta) is a rainfall threshold model, which uses the statistical distribution of rainfall for forecasting the occurrence of landslides. The threshold curves are functions of standard deviation of the cumulated rainfall data, taking into account both long-term and short term-rainfall. To overcome the limitations of statistical rainfall threshold, the real-time monitoring data from MicroElectroMechanical Systems (MEMS) tilt sensors have been integrated with SIGMA model using a decisional algorithm for a test site (Kalimpong) in Darjeeling Himalayas, in the northeastern part of India. Three different models, the SIGMA model, tilt meter readings and the combination of both are compared quantitatively using the precipitation and landslide data of Kalimpong town between July 2017 and September 2020. The results indicate that the integration of tilt meter readings has lowered the number of false alarms issued by SIGMA model from 70 to 38 in the studied period, with an increase in the likelihood ratio from 18.10 to 20.23. The Receiver Operating Characteristic (ROC) curves indicate that the combined approach has the best performance among the models considered in this study, with an area under the curve 0.976. The proposed method was found to have better performance than the other rainfall thresholds derived for Kalimpong region so far, and the prototypal model can be further fine-tuned to develop an operational Landslide Early Warning System (LEWS) for the region. more...

Background Clinical perfectionism has been implicated among risks for developing depression, anxiety, and eating disorders. This study aimed to translate the widely used Clinical Perfectionism Questionnaire (CPQ) into Arabic and examine its psychometric properties. A general population sample of 1598 Saudi adults completed an online survey. Respondents were randomly selected to create two separate samples of n = 400 each, thus meeting the sample size recommendations for Rasch analysis. We applied the partial credit Rasch model to one independent sample to investigate and improve the psychometric characteristics of the scale and replicated our findings with another independent sample of the equal size. Results Minor modifications were required to address local dependency issues and resulted in a good fit of the Arabic CPQ to the unidimensional Rasch model in both samples. The scale demonstrated unidimensionality, invariance across personal factors, and good reliability (PSI = 0.78). As expected, the scale scores were positively associated with depression, anxiety, and disordered eating behaviors. Conclusions Overall, the Arabic CPQ demonstrated robust psychometric properties after minor modifications that did not change the original scale format. The utility and accuracy of the Arabic CPQ can be enhanced by converting ordinal scores into interval scale scores using conversion tables presented in this paper. more...

This paper presents an investigation of ultrathin Cu (In1−xGax) Se2 solar cell which was calibrated from the fabricated cell using Silvaco-TCAD tools. Carrier transport mechanism and conduction band alignment at the CdS/CIGS interface shows a large influence on PV parameters. The influence of the absorber trap density on the electrical characteristics of the single junction cell was investigated under AM 1.5G one-sun (100 mW/cm2) illumination. Further simulations quantify significant improvements in cell efficiency while using a thin Al2O3 material as a rear passivation layer. In addition, the impact of the backside pitch size, opening width, absorber layer doping, and thickness on cell performance is investigated to enhance the cell efficiency. To evaluate our work, the electrical characteristics of the optimized cell were compared to the fabricated cells. more...

The current study aimed to examine thymic stromal lymphopoietin receptor (TSLPR) genetic variation and breast cancer (BC) susceptibility in women in Saudi Arabia. Therefore, 127 blood samples from female patients diagnosed with BC and 116 blood samples from healthy female controls were studied using a genotyping assay to determine the association between three TSLPR single nucleotide polymorphisms (SNPs)-P196L, X201W, and A238V-and the risk of BC progression. In addition, gene expression was evaluated in 20 matching BC and normal tissues using immunohistochemistry. TSLPR protein levels were higher among BC patients than those with matching normal breast tissue. In addition, TSLPR SNP P196L was found to have a significant protective effect on BC progression (OR = 0.4427), although only the T allele for TSLPR P196L had this protective effect against BC progression in participants who were younger than 48 years old. In contrast, no association was found between the T allele and risk of BC in participants who were older than 48 years old, and the CT and TT genotypes were significantly associated with BC risk protection in the older group. The effects of the TT genotype and the T allele were closely associated with a decreased risk of BC in participants with estrogen receptors (ER+) and without them (ER-). Overall, the findings revealed a significant correlation between SNPs in the TSLPR genes and BC progression among women in Saudi Arabia. more...

Urban dynamic temporal analysis is essential for the policymaker, natural resources management plan, decision-makers, and scientific purposes. Satisfactory urban management strategies depend on consistent plotting of land use land cover changes. Remote sensing procedures in temporal change detection bring reliability to the decision taker for wide-cover management plans. Two temporal datasets of images were processed to estimate the urban dynamics in current research. SAR microwave data and MSI optical data were acquired from the European Space Agency in 2016 and 2020. For each dataset, preprocessing and data-specific processing procedures were followed to estimate the Urban Footprint within the study area. The urban coherence technique was applied to SAR data, and the change detection technique based on supervised classification was applied on MSI data to estimate the Urban Footprint. The accuracy assessment was estimated using ground truth points (150) as well as training sites (30). The results indicated that the urban expansion in Jeddah city was increased to be nearly 8% using optical data; however, it was increased to be less than 3% using SAR data. Irrespective of MSI data accuracy assessment (83.19%), SAR data showed more consistent Urban Footprinting (92.35%). Therefore, the urban coherence of the coastal city of Jeddah is reliably emphasized using SAR data over MSI data which is a decision-making significance to manage the natural resources within comparable arid environments. more...

Exogenous potassium (K + ) and endogenous hydrogen sulfide (H 2 S) synergistically alleviate drought stress through regulating H + -ATPase activity, sugar metabolism and redox homoeostasis in tomato seedlings . Present work evaluates the role of K+ in the regulation of endogenous H2S signaling in modulating the tolerance of tomato (Solanum lycopersicum L. Mill.) seedlings to drought stress. The findings reveal that exposure of seedlings to 15% (w/v) polyethylene glycol 8000 (PEG) led to a substantial decrease in leaf K+ content which was associated with reduced H+-ATPase activity. Treatment with sodium orthovanadate (SOV, PM H+-ATPase inhibitor) and tetraethylammonium chloride (TEA, K+ channel blocker) suggests that exogenous K+ stimulated H+-ATPase activity that further regulated endogenous K+ content in tomato seedlings subjected to drought stress. Moreover, reduction in H+-ATPase activity by hypotaurine (HT; H2S scavenger) substantiates the role of endogenous H2S in the regulation of H+-ATPase activity. Elevation in endogenous K+ content enhanced the biosynthesis of H2S through enhancing the synthesis of cysteine, the H2S precursor. Synergistic action of H2S and K+ effectively neutralized drought stress by regulating sugar metabolism and redox homoeostasis that resulted in osmotic adjustment, as witnessed by reduced water loss, and improved hydration level of the stressed seedlings. The integrative role of endogenous H2S in K+ homeostasis was validated using HT and TEA which weakened the protection against drought stress induced impairments. In conclusion, exogenous K+ and endogenous H2S regulate H+-ATPase activity which plays a decisive role in the maintenance of endogenous K+ homeostasis. Thus, present work reveals that K+ and H2S crosstalk is essential for modulation of drought stress tolerance in tomato seedlings. more...

Recently, the digital multimedia cybersecurity has become a research topic of interest due to the fast development of real-time multimedia applications over public networks such as the Internet. Therefore, this research paper introduces an efficient cybersecurity framework for protecting the high-efficiency video coding (HEVC) frames. The suggested selective cybersecurity HEVC framework employs a robust hybrid technique based on watermarking and selective encryption for maintaining confidentiality and achieving copyright protection of the transmitted HEVC information. The watermarking method employs the Homomorphic transform and singular value decomposition in the discrete wavelet transform to increase the immunity of watermarked HEVC streams to attacks. Moreover, the selective encryption technique uses the Chaotic logistic map for encrypting the motion vector difference and the discrete cosine transform sign bits to provide the feature of HEVC format compliance with low encryption overhead cost. An extensive security investigation is carried out for the proposed selective HEVC cybersecurity framework. The obtained experimental outcomes ensure and validate the effectiveness of the selective HEVC cybersecurity framework for HEVC sequences transmission. more...

Saudi Arabia (SA) lies in an arid region where groundwater is the main natural resource; therefore, it is essential to understand the groundwater dynamics for the best groundwater management practice in SA. In Hadat Ash-Sham Farm Experimental Station, SA, water table data from 11 wells and rainfall data were monitored for 16 months. The water table (WT) data is analyzed using the geostatistical method with the ordinary Kriging technique to generate the best WT spatial distribution map for each month and the expected flow direction. The cross-validation technique is used to evaluate the goodness of the developed WT maps. The Kriging maps show two regimes: weak spatial dependence (WSD, the ratio of the nugget to sill > 75%) and strong spatial dependence (SSD, the ratio of the nugget to sill more...

In this paper, we study the dynamics of a predator–prey system under the combined effects of fear, migration and switching phenomena. This study is new in the sense that the dynamics of such system was studied either through fear or migration, or switching, but the combined effects of such three factors are yet to be explored. We observe oscillatory behavior of the system in the absence of fear, migration and switching, whereas the system shows stable dynamics if anyone of these three factors is introduced. After analyzing the behavior of system with fear, migration and switching, we find that the system does not possess periodic solution whenever the predator population experiences intraspecies competition, but in the absence of intraspecies competition among predator population, fear of predators destabilizes the system, whereas on increasing the migration rates, the system first undergoes subcritical Hopf-bifurcation and then supercritical Hopf-bifurcation settling the system to stable coexistence. Existence of multiple limit cycles is also observed. Our results show that switching behavior of predator population supports the survival of prey and predator populations. We extend our model by assuming the fear parameters as time dependent. We find that the nonautonomous system exhibits periodic solutions, whereas the corresponding autonomous system shows stable focus. Moreover, we observe that if the autonomous system undergoes a Hopf-bifurcation through limit cycle oscillations, the corresponding nonautonomous system shows higher periodic solutions. Almost periodic behavior of the system is also observed by setting the fear parameters as almost periodic functions of time. more...

Assessment of future water availability is a challenging task under changing climatic conditions and anthropogenic interventions. The current research focuses on future water resources scenario generation for contributing areas of proposed hydraulic structures generated from the Water Evaluation and Planning (WEAP) System model. The proposed methodology was implemented for the Dwarakeswar-Gandherswari river basin (India) which needs a long-term future water use plan. Bias-corrected Representative Concentration Pathways (RCPs) data were used for climate change analysis through a hydrological model. Different simulation model outputs [e.g. Dynamic Conversion of Land-Use and its Effects (Dyna-CLUE), Soil and Water Assessment Tool (SWAT), Modular Finite-Difference Flow Model (MODFLOW)] were utilized in water evaluation model for a generation of future water resources scenarios. Four scenarios (2010–2030–2050-2080) were generated for the sustainability of limited water resources management strategies. SWAT simulated results show an increase in river discharge for 2030 or 2080 and a decrease for 2050. MODFLOW simulated results show a visible groundwater storage change for 2030 but minimal change for 2050 and 2080 scenarios. The results also show a decrease in agricultural land and an increase in population for the contributing areas of three hydraulic structures during 2010–2030–2050-2080. These results provide a piece of valuable information for decision-makers in future water management plan preparation. more...

Nitric oxide (NO), a signaling molecule with diverse physiological functions, improves immunity of the plant against different environmental stresses. Heavy metal stress-induced structural and functional damages in cells are common consequences. Seed germination and seedlings development are crucial phases in the life cycle of a plant. The present experiment was designed to investigate how NO suppresses hexavalent chromium Cr(VI)-provoked impairment in the key processes during seed germination and seedlings development of tomato. This study reports that Cr(VI) stress significantly impaired seed germination attributes and the activity of hydrolyzing enzymes, such as α-amylase (α-A) and protease (Pr). However, exogenous NO donor sodium nitroprusside substantially improved seed germination parameters and upregulation of α-A and Pr. Furthermore, NO improved the content of nitrogen (N), NO, and proline (Pro), and modulated the activity of enzymes involved in Pro and N-assimilation. Under Cr(VI) toxicity conditions, NO improved the content of metal ligation compounds (non-protein thiols and total thiols), ascorbate and glutathione (GSH), and maintained higher content of GSH in glutathione pool (GSH:GSSG) and suppressed the formation of 4-hydroxy-2-nonenal and protein carbonylation, and electrolyte leakage. It may be concluded that NO improved the activity of hydrolyzing and Pro and N-metabolism enzymes. Application of NO also enhanced non-enzymatic antioxidants, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity under Cr(VI) toxicity conditions, thereby improved enhanced seed germination and seedlings vigor. more...

We explore numerically the Darcy–Boussinesq convective flow of water, kerosene, and engine oil through the glass ball, aluminum foam and sandstone porous medium inside a right-angle trapezoidal enclosure taking into consideration of thermal stratification. The bottom and left walls of the enclosure are uniformly heated, whereas thermal insulation is considered for the upper wall of it. Thermal stratification is applied to the right wall. The governing nondimensional partial differential equations are simulated using the Galerkin weighted residual finite element method with the help of COMSOL Multiphysics. We explored the time evolution of solutions and investigate the effects of the Rayleigh number, thermal stratification parameter, porosity parameter, types of the solid matrix and working fluids, and on the average Nusselt numbers, streamlines and isotherms. The simulated results confirm that the heat transfer rate amplifies with the increase in Rayleigh number and diminishes with the thermal stratification, porosity and aspect ratio of the enclosure. The results further guarantee that engine oil and aluminum foam perform better for heat transfer intensification. A two-cell flow is obtained for a stronger thermal stratification. more...