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In recent years, the remarkable photoelectric properties exhibited by perovskite materials have stimulated scientific inquiry, prompting investigations into novel perovskite variants and derivatives characterized by environmentally friendly attributes and robust stability. These materials offer potential as efficient solar light harvesters. Our study concentrates on elucidating the structural, electronic, and optical properties of the newly discovered stable lead-free double perovskite K2AgSbBr6, employing first-principles methods rooted in Density Functional Theory (DFT). We confirm the structural and dynamical stabilities of K2AgSbBr6 through computational analysis. Our calculations reveal that the examined compound exhibits characteristics of an indirect semiconductor, with a band gap of 0.857 eV (L-X). Notably, our findings demonstrate that the compound displays enhanced photovoltaic performance, as evidenced by elevated optical absorption coefficients exceeding 105 cm−1, surpassing those of CH3NH3PbI3. These results underscore the potential of K2AgSbBr6, a novel lead-free double perovskite, as a promising candidate for exceptional light-absorbing material spanning the UV and visible spectra.

In this groundbreaking study, we unveil the remarkable structural, electronic, and optical Properties of the newly discovered double perovskite material, K2AgBiI6, presenting a paradigm shift in materials science. The unique crystal structure and diverse atomic interactions inherent in this double perovskite make it an up-and-coming candidate for various technological applications, particularly in photovoltaics; owing to its stability and resistance to heat and humidity, we aim to shed light on the extraordinary potential of K2AgBiI6. Our study provides valuable insights for researchers engaged in tailored material design. We anticipate that the exceptional electronic properties of K2AgBiI6 will not only redefine the boundaries of materials engineering but also catalyze unprecedented advances in sustainable technology. Employing the powerful computational tool CASTEP, we conducted detailed electronic structure calculations within the framework of Density Functional Theory (DFT) to unravel the electronic properties of the double perovskite K2AgBiI6. Our investigation thoroughly explored structural properties, band structure, total density of states (DOS), and partial density of states (PDOS). Furthermore, we systematically examined the influence of different exchange-correlation functionals, including LDA, GGA, and m-GGA, on the electronic and optical features of the material by presenting a comparative analysis of these approximations.

Effective disaster management heavily relies on accurate flood susceptibility mapping. The fuzzy analytic hierarchy process (FAHP) is adept at considering the imprecise nature of decision-making criteria. This study assesses FAHP's effectiveness in flood susceptibility mapping, comparing it with the conventional analytic hierarchy process (AHP). By using Geographic Information System-analyzed remotely sensed data, the research systematically evaluates flood risk southeast of Algiers. Various datasets, including Digital Elevation Model, slope, precipitation, and land use maps, were collected via remote sensing. A linear fuzzy membership function transformed the data into fuzzy values. AHP determined the importance of each dataset, with calculated weights multiplied by corresponding fuzzy values. Fuzzy analysis combined these characteristics into a five-category flood risk map, verified with Google Earth and satellite images. Results indicate a high potential for flood hazard mapping, categorizing 30% of frequently flooded regions as high risk. Maps reveal north basin areas are more flood prone due to excessive precipitation, and urban areas in floodplains are vulnerable. Receiver operating characteristic (ROC) curves and area under the ROC curve (AUC) assessments demonstrate AHP and FAHP's effectiveness. AUC values of 88.40 and 92% indicate that both models accurately predict flood-prone areas. FAHP excels, reducing subjectivity and ambiguity in human judgments. HIGHLIGHTS Fuzzy analytic hierarchy process (FAHP) excels in handling uncertain factors for accurate flood maps.; Utilizes diverse remote sensing data, converted into fuzzy values.; Comparative study in Sahel shows FAHP's superior performance (area under the receiver operating characteristic curve: 92%) in mitigating judgment uncertainty.; Maps reveal high susceptibility in heavily precipitated northern regions and floodplain urban areas.;

Hydrological modeling is a critical and decisive technique for estimating hydrological processes and the availability of water resources. In our research, we used Hydrologic Modeling System (HEC-HMS), a 4.4 version, to achieve the affected goals, and a watershed in the east of Algeria, known as Rhumel Smedou watershed, was chosen as a case study which covers an area of 1,083 km2. A Geographic Information System (GIS) was used to analyze and process the Digital Elevation Model 30-meter resolution data accompanied with Landsat of Land Use Land Cover 10-meter resolution with accuracy to extract and deduce the basic inputs of the simulation model, which are: curve number (%), lag time (mn), impermeability (%), and rainfall (Ia) (mm). The research purpose is to compute runoff depth and volume rate for four extreme events. Two events are chosen for model calibration and two for model validation. The results of the statistical tests [NSE (%) RMSE_PBIAS (%)] proved the success and ability of the model to achieve the research objectives, and their averages were as follows: [82%_0.45_32.55%] for calibration phase, and [77%_ 0.45_30.95%] for validation phase. After calibrating and validating the effectiveness of the model, the volume and flow were predicted for different return periods (2y, 10y, 50y, and 100y).

Introduction: The bronchogenic cyst is a congenital anomaly of the trachea and the bronchi resulting in a malformation that develop in the bronchial tree, most often in the middle mediastinum. It is a benign pathology, often asymptomatic, however in the case of a large bronchogenic cyst, signs of compression of the intra-thoracic organs appear and early surgery is necessary to avoid complications. Case presentation: A 49-year-old patient was referred to our department with dry cough, dyspnea and chest tightness progressing for six months. Radiological exploration concluded that a giant bronchogenic cyst, 90 mm in diameter, was very probable. Surgery was performed via a right posterolateral thoracotomy. Intraoperatively, there was a large cystic formation 100mm*80 mm of the middle mediastinum in intimate contact with the origin of the right pulmonary artery, the lower right pulmonary vein as well as the right atrium exerting a compressive effect on the bronchi. The lesion was firmly adhered to the pericardium. The cystic was ‘en bloc’ resected in totality. The postoperative course was uncomplicated. Histological examination confirmed diagnosis of a bronchogenic cyst. The patient was asymptomatic throughout the follow-up period. Clinical discussion: Apart from the possibility of malignant degeneration, a bronchogenic cyst can increase in size and become huge causing serious complications. Despite the predictive diagnostic value of imaging, definitive diagnosis of a bronchogenic cyst is confirmed by surgical excision and pathological examination. Conclusions: Surgery is almost obligatory especially if the cyst is above a certain size (about 60 mm) and in the case of giant bronchogenic cysts.

This study investigates the electronic and optical properties of calcium-doped strontium hydride (SrH2) using first-principles density functional theory (DFT) calculations via the CASTEP code with generalized gradient approximation (GGA). We explore the impact of calcium (Ca) doping on the electronic band structure, density of states (DOS), and optical absorption spectra of SrH2. Our results show that Ca doping significantly alters the electronic properties of SrH2, notably increasing the indirect bandgap from 1.3 eV to 1.6 eV. The DOS analysis reveals new states near the Fermi level, primarily from Ca 3d orbitals. Moreover, the optical absorption spectra display enhanced absorption in the visible range, suggesting the potential for optoelectronic applications. This research highlights the feasibility of tuning the electronic and optical characteristics of SrH2 through Ca doping, thus opening the way for the generation of advanced materials with tailored properties.

The current research examines the runoff response in the Bouhamdane watershed in Algeria using the soil and water assessment tool (SWAT). The SWAT model is applied for the Bouhamane watershed, which includes three sub-watersheds and 45 Hydraulic Response Units (HRUs). To assess the ability and effectiveness of the model, one-gauge station in the basin (sabat) was chosen. Monthly discharge flow data are sourced from Algeria's National Water Resources Agency (NWRA). The soil and water assessment tool calibration uncertainty programs (SWAT-CUPs) with the sequential uncertainty fitting (SUFI 2) algorithm were used to calibrate and validate the model. The model was run from 1985 to 2004, with a calibration period between 1985 and 1994 and a validation period between 1995 and 2005. The model's runoff simulation efficiency has been improved by adjusting watershed input parameters. The SWAT model's performance was assessed statistically (coefficient of determination [R2], Nash-Sutcliffe Efficiency Coefficient [NSE], and Percent BIAS [PBIAS]). The monthly calibration R2, NSE, and PBIAS were 0.89, 0.68, and 43, respectively, and the monthly validation R2, NSE, and PBIAS were 0.78, 0.76, and 10.4, respectively. These results support that the SWAT model is an effective tool for simulating the surface runoff of the Bouhamdane watershed.

Land use and land cover changes in coastal cities can influence drainage sys-tems in ways that affect surface overflows and the infiltration potential of a land surface, making flooding one of the drivers. This research aims to demonstrate the spatiotemporal dynamics of LULC and their combined impact on rainfall and flood height in Skikda, Algeria. The research uses remote sensing (RS) and geographic information systems (GIS) to determine the type and location of LULC changes in Skikda. The supervised classification methodology used the maximum likelihood technique (MCL). Changes were identified in five categories: built-up areas, green spaces, bodies of water, agriculture, and vacant land. In Q-GIS 3.28.2, Landsat 4-5 (TM) data from 1984 and 2004 and Landsat 8-9 (OLI)/TIRS data from 2019 were used based on the United States Geological Survey (USGS). The results show that the impervious built-up area has changed significantly (44.01%) due to massive urbanization and rapid industrialization, which would affect heavy rainfall activity and increase flood height due to the intense imperviousness of the affected soil (from 27% to 44%). The precipitation and flood height were examined and compared with observations to investigate the impact of the LULC model modification during the flood. The comparison of three flood events (1984, 2004, and 2019) revealed that the change in the LULC model is the main factor increasing flood risk in the study area. This study demonstrates the importance of considering temporal changes in land use, land cover, rainfall, and flood height when mapping floods in urban cities.

This study investigates the electronic and optical properties of calcium-doped strontium hydride (SrH2) using first-principles density functional theory (DFT) calculations via the CASTEP code with generalized gradient approximation (GGA). We explore the impact of calcium (Ca) doping on the electronic band structure, density of states (DOS), and optical absorption spectra of SrH2. Our results show that Ca doping significantly alters the electronic properties of SrH2, notably increasing the indirect bandgap from 1.3 eV to 1.6 eV. The DOS analysis reveals new states near the Fermi level, primarily from Ca 3d orbitals. Moreover, the optical absorption spectra display enhanced absorption in the visible range, suggesting the potential for optoelectronic applications. This research highlights the feasibility of tuning the electronic and optical characteristics of SrH2 through Ca doping, thus opening the way for the generation of advanced materials with tailored properties. [ABSTRACT FROM AUTHOR]

In recent years, double perovskite oxides have gained attention as promising candidates in the realms of solar cells and catalysis. By adjusting their composition and engineering the band gap, numerous materials are being developed for energy-related applications. Oxide perovskites offer the benefit of a longer carrier lifetime compared to halide perovskites, which is advantageous for energy applications. In this study, we present a systematic theoretical analysis of a double perovskite oxide, examining his composition. The associated electronic and optical properties are discussed, along with prospects for identifying highly efficient materials within this family. This paper reports the study of electronic and optical properties of double perovskite oxide LaFeWO6 by utilizing the FP − LAPW method within the framework of (DFT). Results of density of states and energy bands are presented. The direct band gaps have been found for the systems by using the GGA approximation. Calculations of optical properties is also presented by considering the variations of optical parameters as a function of incident photon energy. The results indicate that LaFeWO6 exhibits a suitable band gap (0.71eV) for visible light absorption, along with promising electronic properties, making it a candidate for photocatalytic and photovoltaic applications.

Bibliometric analysis is crucial in understanding the evolution of research trends and knowledge in various fields. This study applies bibliometric analysis to explore the growth of the research paradigm on agility in the FinTech literature, using co-citation analysis and bibliographic coupling of selected articles. Based on this bibliometric analysis, the evolution of research on agility in the FinTech domain has been prepared, focusing on the literature related to FinTech agility between 1984 and 2022. In this study, we also address the limitations of individual analyses from Scopus and Web of Science (WOS) and propose a comprehensive approach by merging the two research databases. The results reveal significant disparities between authors, publication influences, and keyword occurrences between the WOS and merged databases. Our research highlights the importance of combining a database approach in bibliometric studies, providing valuable insights for scholars, researchers, and stakeholders. Finally, the in-depth bibliometric analysis demonstrates the significance of “FinTech agility” in the rapidly evolving FinTech sector. Financial technology companies’ agility, or ability to adapt quickly, is the foundation of their success and innovation.

In this paper, an efficient algorithm is proposed for solving one dimensional time-space-fractional telegraph equations. The fractional derivatives are described in the conformable sense. This algorithm is based on shifted Chebyshev polynomials of the fourth kind. The time-space fractional telegraph equations is reduced to a linear system of second order differential equations and the Newmark’s method is applied to solve this system. Finally, some numerical examples are presented to confirm the reliability and effectiveness of this algorithm.