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Atmospheric stability is considered as one of the most important factors affecting the increase or decrease in wind speed in the atmosphere and thus affects the wind energy density. This study aims to analyze the stability of the atmospheric conditions in southern part of Iraq, specifically in the Ali Al-Gharbi region, using one of methods to determine atmospheric stability called Monin-Obukhov length . Field data of horizontal and vertical wind speed and air temperature collected at three heights (10m, 30m, and 50m) in 2017 from tower installed in Ali Al-Gharbi region. The results show that the vertical wind speed increases with height up to 30 m and decreases at 50 m, while the horizontal wind speed increases as the height increases. The friction velocity , surface heat flux , momentum flux and shear stress were calculated and the stability conditions were determined. Results revealed that stable atmospheric condition was the most frequent with about 59% occasions occurring during the year followed by unstable (40%) and neutral (1%) conditions. The highest wind energy density was in stable conditions (0 ≤ L< 200), with percentage (58% - 57%) in spring season at both heights 10m and 50m, respectively, followed by unstable conditions (-200 < L ≤ 0), while the lowest wind energy density was in neutral conditions (-200 ≤ L ≥ 200) with percentage (1.3% - 0.8%) in autumn season.Atmospheric stability is considered as one of the most important factors affecting the increase or decrease in wind speed in the atmosphere and thus affects the wind energy density. This study aims to analyze the stability of the atmospheric conditions in southern part of Iraq, specifically in the Ali Al-Gharbi region, using one of methods to determine atmospheric stability called Monin-Obukhov length . Field data of horizontal and vertical wind speed and air temperature collected at three heights (10m, 30m, and 50m) in 2017 from tower installed in Ali Al-Gharbi region. The results show that the vertical wind speed increases with height up to 30 m and decreases at 50 m, while the horizontal wind speed increases as the height increases. The friction velocity , surface heat flux , momentum flux and shear stress were calculated and the stability conditions were determined. Results revealed that stable atmospheric condition was the most frequent with about 59% occasions occurring during the year followed by unstable (40%) and neutral (1%) conditions. The highest wind energy density was in stable conditions (0 ≤ L< 200), with percentage (58% - 57%) in spring season at both heights 10m and 50m, respectively, followed by unstable conditions (-200 < L ≤ 0), while the lowest wind energy density was in neutral conditions (-200 ≤ L ≥ 200) with percentage (1.3% - 0.8%) in autumn season.

Geotechnical engineers are currently confronted with the challenge of identifying innovative and efficient approaches to increase bearing capacity and minimize foundation settling. As a result, the skirt is regarded as one technique for enhancing the shallow foundation's carrying capability on various soil types. The skirt work mechanism involves the confining of soil beneath the foundation, resulting in a reduction of settling for the foundation. Soil engineers have endeavored to develop this approach as a substitute for pile foundations in normal structures. These foundations exhibit versatility in their applicability, as they may be useful in diverse settings, including marine environments, coastal areas, and arid terrains. This study provides a comprehensive evaluation of various research conducted on skirted foundations in different soil conditions. The objective is to assess the increase of bearing capacity and decrease in a settlement achieved via the utilization of skirted foundations. This assessment is based on laboratory testing, field tests, centrifuge models, numerical methods, and theoretical analysis; These investigations are employed to examine the behaviors skirted footing.

Background and Objectives: Blood transfusion is a life-saving intervention but may cause nonfatal to fatal untoward events. Therefore, for safe blood transfusion, various adverse reactions need to be identified and steps should be taken to reduce such events. The aim of this study was to determine the incidence and analyze the types of acute transfusion reactions (ATRs) with associated factors. Patients and Methods: All ATRs reported to the transfusion medicine department from January 2016 to December 2020 were retrospectively reviewed and analyzed. The incidence of ATRs and its associated factors were assessed. Results: During the study period, a total of 39,070 units of blood were issued, out of which there was an incidence of 0.24% (n = 95) ATRs mostly seen in females and older patients aged above 60 years. Most common ATR was febrile nonhemolytic transfusion reactions (51.6%, n = 49), followed by allergic reaction (35.8%, n = 34). The most common symptom was chills and rigor (41.1%). The frequency of reactions was significantly higher with packed red blood cell transfusion (62.1%). Patients with previous transfusion history (n = 63, % = 66.3, P = 0.711) had more ATRs. Conclusion: By this study, the authors want to create awareness among health personnel involved in the transfusion chain is necessary to establish a proper hemovigilance system.

Background and Objectives: In 1939, D antigen was discovered which is believed to be the most immunogenic antigen in Rhesus (Rh) blood group system. There are some D variants such as weak D, partial D, and DEL due to gene polymorphism. These variants can cause RhD-positive person to behave like RhD negative which could result in alloimmunization. Clinically weak D antigen is very important due to its strong immunogenicity in spite of its low frequency. Hence, we need to know the prevalence of weak D variants in the community. The purpose of this study is to find out weak D prevalence among the Bangladeshi population. Methods: It is a retrospective study done over the last 5 years, from January 2015 to December 2019, at the department of transfusion medicine of three tertiary care hospitals in Bangladesh. A total of 177,702 patients were enrolled in the study. Blood samples that were negative for RhD were tested for weak D by indirect antiglobulin test according to institutional protocol. Results: Out of 177,702 patients, 7359 (4.1%) were found to be RhD negative and among those, 14 (0.19%) were weak D antigen positive. Conclusion: Weak D antigen is prevalent in Bangladesh and every RhD-negative individual should be checked for the presence of weak D to prevent RhD alloimmunization.

The present article has utilized the WIEN2k computational code to examine the structural, elastic, electronic, magnetic, thermoelectric, and dynamic aspects of the CoCrS Half-Heusler (HH) compound. In this work, calculations have been performed by utilizing the full-potential linearized augmented plane wave method using density functional theory. The electronic bandgap was better interpreted by using the modified Becke–Johnson exchange–correlation functional. We evaluated various electronic properties of the CoCrS HH compound, including band structure plots and density of states. Furthermore, we examined the magnetic characteristics through the computation of magnetic moments and the examination of the spin-polarized electronic state behavior. We also determined the elastic properties of the CoCrS HH compound. These properties, which include stiffness, resilience, and general stability, provide important information about how the material responds to mechanical deformation. Moreover, we explored the electronic structure and found that type 5 of CoCrS exhibits a metallic behavior. In addition, we examined the compound's thermoelectric properties. Finally, the dynamical properties indicate that type 5 of CoCrS is dynamically stable. [ABSTRACT FROM AUTHOR]

Both electronic as well as magnetic characteristics of Co1-xFexMnSb (x = 0, 0.25, 0.50, 0.75, 1) composite have been studied by employing the first principle (FP) study. The FP calculation was attained using the density functional theory (DFT). The exchange–correlation term has been examined inside the generalized gradient approximation (GGA), as implemented in the Wien2k code. According to predictions, the type 3 structure of atoms will be the tremendous, optimum, and have the smallest amount of energy. The formation energy of CoMnSb and FeMnSb was minimum so it demonstrates that these alloys are optimized. CoMnSb and FeMnSb are half-metallic (HM) having the value of magnetic moment 3µB and 2µB, respectively in good agreement with the Slater-Pauling rule. These results suggest that the Mn atoms are the primary source of the magnetic moment. The values of elastic constants were determined by the crystal structure's symmetry. Additionally, the bulk modulus B, shear modulus G, Young's modulus E, as well as Poisson's ratio v have been determined using the Voigt-Reuss-Hill (VRH) method. Both examined compounds, CoMnSb and FeMnSb, have computed B/G ratios higher as compared to 1.75, indicating that these alloys are malleable. [ABSTRACT FROM AUTHOR]

The structural, mechanical, and electronic properties of rubidium iodide (RbI) have been extensively investigated utilizing the generalized gradient approximation (GGA) and the full-potential linearized augmented plane wave (FP-LAPW) approach. The potential was roughly calculated using a modified Becke–Johnson (mBJ) approximation, which increased the precision of the electronic properties. In this study, RbI is analyzed in a wide range of crystal structures, including topologies like rock salt (RS), CsCl, zinc blende (ZB), NiAs, and wurtzite (WZ), among others. Our research shows a strong relationship between the material's physical properties and the conclusions drawn from both theoretical and experimental studies. Significantly, our results show that the RS form corresponds to RbI's ground state. All the aforementioned topologies display wide-bandgap semiconductor capabilities, according to further examination of their electronic band structures. Notwithstanding these findings, it was discovered that RbI has a poor fracture resistance due to its low bulk modulus. Born's stability analysis has shown that RbI is stable in the RS, CsCl, ZB, NiAs, and WZ structures. All RbI structures were discovered to have ionic bonding and to be ductile, and every stabilized system displayed anisotropic stability. Using the Cauchy pressure and Poisson's ratio, the stiffness of the systems was evaluated, with the RS structure proving to be the stiffest. Overall, the findings illuminate the physical properties of RbI, providing valuable insights that could facilitate the creation and refinement of novel materials possessing desirable characteristics. [ABSTRACT FROM AUTHOR]