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Due to the necessity of performing thermal operations, heat exchangers are widely employed in many different areas. The heat transfer and fluid flow within a spiral double-pipe heat exchanger fitted with a novel turbulator were numerically assessed in this work. The presented novel turbulator is a curved tube with holes incorporated into its thickness and spiral ribs on its inner wall. The turbulator wall's curved rib design produces secondary flows at the turbulator output when fluid flows through the tube and the perforations. A commercial CFD tool, based on the finite volume technique, was used to conduct the numerical simulations. The fluid flow regime is turbulence (Re = 8,000 – 14,000). Two sections make up this work. The first portion looked at how the hydrothermal behavior of the fluid flow inside the proposed turbulator was affected by the angle at which the curved ribs rotated. For this angle, three values were considered: θ = 30, 90, and 150°, and the outcomes were contrasted with those of a plain spiral double-tube heat exchanger (turbulator not included). Then, the number of embedded holes in the turbulator's thickness changes in the second part, and three values of N = 12, 16, and 20 were considered. According to the first part's findings, the model exhibiting θ = 90° had a greater thermal performance factor at Re = 10,000. This model has a more noteworthy thermal performance factor than the models with θ = 150 and θ = 30° by approximately 15.62 % and 22.65 %, respectively (at Re = 10,000). Furthermore, the second section's numerical findings showed that the model with N = 20 had more extraordinary thermal performance at Re = 10,000. Model N = 20 has a thermal performance factor of about 16.93 % and 17.55 % greater than models N = 16 and N = 12. Within the proposed heat exchanger, the recommended turbulator produced a sizable rotating flow, and including embedded holes significantly reduced the pressure drop this kind of turbulator causes.

Ciprofloxacin (Cip) and hydrocortisone (Hyd) were simultaneously measured as hydrochloride and sodium succinate, respectively, using the H-point standard addition method (HPSAM). The approach can precisely identify Cip in the presence of Hyd with various analyte-to-interference ratios (5:5, 5:10, 10:5, 10:10) µg.mL-1, in mixed samples containing (1-5µg.ml-1) of Cip, at the wavelengths of (236 and 257) nm. In the same way, Hyd was analyzed in the presence of Cip in different analytes with an interference ratio of (5:5, 5:10, 10:5, 10:10) µg.mL-1, in mixed samples containing (1-5 µg.mL-1) of Hyd, at wavelengths of (266 and 278) nm. The satisfactory results show good reproducibility of the developed method (RSD equals 0.9735-1.6825 and 0.9692-1.7671 for Cip and Hyd, respectively). The results also show that the excipients had no influence on the assaying of the above drugs (Recovery, 98.87–101.73). The recommended technique has successfully been used to determine the Cip and Hyd in pharmaceutical composites simultaneously with an RSD range of (0.972 to 1.671) and (0.898 to 1.820) for Cip and Hyd, respectively.

An accurate and sensitive determination procedure has been established for the quantification of cefdinir in pure and pharmacological formulas. The approach was dependent on derivatizing cefdinir with sodium anthraquinone-2-sulfonate (SAS) in an alkaline medium to produce a magenta-colored derivative with a maximum absorbance at 517 nm against the reagent blank. Different factors affecting the interaction of cefdinir with SAS were studied carefully and optimized, such as the buffer value, medium acidity, the duration of hydrolysis, and the reagent percentage. Under optimized conditions, a linear calibration curve with a correlation coefficient of R2 = 0.9995 was obtained over the concentration range of cefdinir 0.5–100 μg/mL. The values of the parameters that represented the sensitivity of the method were satisfactory, i.e., the limit of detection, the limit of quantification, as well as Sandell's sensitivity (л) were 0.1 μg/mL, 0.5 μg/mL, and 0.064 μg/cm2/0.001 Au, respectively. The relative standard deviation was below 1.35%, while the percentage recovery was 99.930%–102.257%. The mole ratio of the colored complex was estimated by following Job's method of continuous variation, which indicated that the cefdinir-SAS ratio was 1:1. The suggested approach was proven to be adequately accurate, precise, and without interfering with common excipients and additives. Thus, it could be implemented successfully for the standard determination of cefdinir in its pure and pharmaceutical forms.

In the rapidly evolving telecommunications industry, organizations in Bangladesh are facing the challenge of improving their performance to stay competitive. However, there is limited research on how big data analytics (BDA) impacts organizational performance (OP) in this context. Therefore, this study examines the impact of BDA on OP in Bangladesh's telecommunications industry, with green innovation (GI) and knowledge management (KM) as mediating variables, and big data analytics technical capabilities (BDATCs) as a moderating variable. We collected data from 384 management-level employees across five major telecom companies in Bangladesh using a structured survey questionnaire. Our analysis employed partial least squares structural equation modeling (PLS-SEM) with Smart-PLS 4.0 software. The findings indicate that BDA positively influences OP, and both GI and KM significantly mediate this relationship. However, while BDATCs enhance the BDA–OP relationship, they do not significantly moderate the BDA–GI link. These results underscore the importance of integrating BDA with KM and GI to boost organizational performance. Telecom companies should invest in advanced data analytics, foster a culture of sustainability, and enhance knowledge management practices to achieve superior performance. This study contributes to the Resource-Based View (RBV) theory by demonstrating the strategic role of BDA, GI, and KM in a developing economy context. Future research should expand this investigation across different sectors and consider longitudinal approaches to capture the dynamic nature of BDA's impact on organizational performance. [ABSTRACT FROM AUTHOR]

A sensitive, accurate, and affordable colorimetric method was developed for assaying prednisolone (PRZ) in various medicinal forms. The procedure involves the oxidation of PRZ by ferric ions, followed by complexation of the resulting ferrous ions with ferricyanide to produce a greenish-blue product. Common complexation conditions were thoroughly investigated. The mole ratio of FeCl3·6H2O to K3Fe(CN)6 was 8:1. The proposed mechanism of complexation was suggested and considered. Various parameters were optimized, including the reduction of the colorimetric reaction temperature to 50°C and the duration of heating and analysis to 20-30 minutes. The calibration curve was linear over the range of 1-60 µg/mL. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.5 µg/mL and 1 µg/mL, respectively. Spiking actual samples with standard PRZ showed recoveries within the 97.3-100.1% range. The method exhibited high precision, with an RSD% of less than 1.5%. Additionally, the study confirmed that common pharmaceutical excipients did not interfere. Real medicinal samples, including tablets, syrup, eye drops, and creams, were successfully examined for direct analysis of PRZ using the developed methodology, demonstrating its suitability for routine analysis of various PRZ-containing drug formulations. [ABSTRACT FROM AUTHOR]

Chloroquine and Hydroxychloroquine drugs are widely prescribed for malaria disease. Since the end of 2019, humans have been under threat due to a disease called (COVID-19), which was first reported in China. Many methodical approaches have been reported to quantify chloroquine and hydroxychloroquine in blood, urine, plasma, serum, and pharmaceutical dosage form. Some of these techniques are spectrophotometry, liquid chromatography with a mass detector, gas chromatography, and ultra-performance, high-performance liquid chromatography (HPLC), in addition to electrochemical methods. This literature review discusses various analytical methods for the determining hydroxychloroquine and chloroquine.

Medicines comprising fosfomycin are prescribed for urinary tract infections. These drugs are available for oral use as tromethamine and calcium, while fosfomycin-sodium and disodium are given for intravenous (IV) and intramuscular (IM). Many quantitative analytical methods have been reported to estimate Fosfomycin in blood, urine, plasma, serum, and pharmaceutical dosage formulations. Some techniques were spectrophotometric, mass spectrometry, gas chromatography, high-performance liquid chromatography, and electrochemical methods. Here we perform a rapid narrative review that discusses and comparison between them of various analytical methods for the determination of Fosfomycin-containing drugs.

A spectrophotometric determination of azithromycin was optimized using the simplex model. The approach proved to be accurate and sensitive. The analyte reacted with bromothymol blue (BTB) to form a colored ion pair, which was extracted in chloroform in a buffer medium of pH 4 potassium phthalate. The extracted colored product was assayed at 415 nm, exhibiting a linear quantification range of 1-20 µg/mL. The LOD was 0.671 µg/mL, with a correlation coefficient of 0.9998 and an RSD% of 0.96±0.2. The molar absorptivity was 20253.5 L/mol·cm. The excipients did not interfere with the proposed method for assaying azithromycin in curative formulations. [ABSTRACT FROM AUTHOR]

Purpose: This study analyzes the impact of the value relevance of accounting information on price-to-earnings ratios in Pakistan during the stock market boom and bust period. Design/Methodology/Approach: Data from 322 non-financial firms listed in PSX from 2005 to 2022 is used in a study. The financial variables data has been hand-collected from annual reports published on the company’s websites and PSX Data Stream. The ADF test and panel OLS method are used for data analysis. Findings: The findings show that the EPS and book value variables positively and significantly influence the price-to-earnings ratio during the market boom and bust period. The CEPS, net income, and change in net income are found to be insignificant factors of price-to-earnings during market boom and bust periods. Implications/Originality/Value: It is concluded that VRAI plays an imperative role in influencing price-to-earnings ratios; therefore, investors should consider this information to invest in the stock market. [ABSTRACT FROM AUTHOR]

Background: Toxoplasmosis is one of the most important causes for abortion in women. The immune responses have a role in the outcome of such infection in gestated women. Aim: The current study was designed to investigate the immune profile in aborted Iraqi women with toxoplasmosis. Materials and Methods: Fifty-five aborted women and 29 healthy control women were enrolled in this study. Enzyme-linked immunosorbent assays were used to estimate serum levels to each of interleukin-1 alpha (IL-1α), granulocyte-monocyte colony-stimulating factor, IL-8, IL-4 IL-10, IL-12, interferon gamma (INF-γ), and IL-6. Single-radial-immunodiffusion assay was used to estimate serum levels of C3, C4, and total immunoglobulin gamma. Results: Serum levels of IL-8 showed significant elevation, while IL-6 and INF-γ showed significant dropping in infected women compared to control. Other immune factors showed nonsignificant differences between the two groups of the present study. Conclusion: Disturbance of immune response associated with toxoplasmosis may explain the success of parasite in escaping from discrimination and elimination by the immune system then supporting its survival and replication.

Circular crested weirs have been used for a long time due to their simplicity in design, low cost and accurate measurement. The Computational Fluid Dynamics (CFD) based software ANSYS FLUENT has been used in this investigation. The CFD model has been applied to explore various flow features over a circular crested trapezoidal weir. The volume of fluid (VOF) technique was used in this work. Two weir conditions with and without roughness elements and three discharges values for each weir case were used. The flow characteristics investigated include coefficient of discharge, water surface profiles and velocity profiles. The roughness element remained submerged in all the simulation cases. The k-1 turbulence model was used for the CFD simulation. After validation, the flow characteristics like the free surface profiles, coefficient of discharge, vertical velocity profiles at the upstream and downstream of the weir and the velocity contours were investigated for varying discharges and roughness. A comparison was drawn for these properties for a channel with and without roughness element. [ABSTRACT FROM AUTHOR]

A sensitive and environmentally benign spectrometric method was developed for quantifying Meprobamate (MEP). The analyzed MEP was derivatized into a colored complex and determined spectrometrically. The colorimetric analytical parameters were optimized and validated. Low limit of detection (LOD) was achieved down to 1.88×10-6 mol/l while the limit of quantification (LOQ) was extended over the range of 1.97×10-6 - 1.35×10-3 mol/l. The high precision has been denoted by the 1.54% value of the coefficient of variation. The recovery was 96.07%, while the RSD (n=3) was 1.05 - 1.19%. The apparent molar absorptivity (Æ) obtained within 1154.7 - 1691.9 L.mol-1.cm-1. The outcomes have signified the high sensitivity of the technique. Furthermore, the avoidance of any traditional sample preparation steps prior to the analysis make the method an excellent environmental approach. There were no analytical interferences with the common composites. The method has been successfully verified for the quantification of MEP content in bulk pharmaceutical matrix and can be applied to determine other environmentally toxic carbamates.

Prodigiosin is a ‘natural red pigment produced by Serratia marcescens which exhibits immunosuppressive and anticancer properties in addition to antimicrobial activities. This work presents an attempt to maximize the production of prodigiosin by two different strategies: one factor at time (OFAT) and statistical optimization. The result of OFAT revealed that sucrose and peptone were the best carbon and nitrogen sources for pigment production with concentration of prodigiosin of about 135 mg/ L. This value was increased to 331.6mg/ L with an optimized ratio of C/N (60:40) and reached 356.8 with pH 6 and 2% inoculum size at end of classical optimization. Statistical experimental design based on Response surface methodology was conducted to optimize the composition of trace element. The design revealed that the predicted prodigiosin production of 406 mg/L can be achieved when concentrations of trace element CaCl2·2H2O, FeSO4·4H2O, MgSO4·7H2O and MnSO4·4H2O were equal to 9.22, 0.32, 0.67 and 2.48 g/L, respectively. The actual production of prodigiosin in the optimized medium was 375 mg/L. Growth kinetics of S. marcescens were evaluated in optimized medium which revealed that prodigiosin was ‘non-associated growth’ secondary metabolite with maximum production of approximately 365.7 mg/L obtained after 54 hours of incubation.

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The catalytic cracking conversion of Iraqi vacuum gas oil was studied on large and medium pore size (HY, HX, ZSM-22 and ZSM-11) of zeolite catalysts. These catalysts were prepared locally and used in the present work. The catalytic conversion performed on a continuous fixed-bed laboratory reaction unit. Experiments were performed in the temperature range of 673 to 823K, pressure range of 3 to 15bar, and LHSV range of 0.5-3h-1. The results show that the catalytic conversion of vacuum gas oil increases with increase in reaction temperature and decreases with increase in LHSV. The catalytic activity for the proposed catalysts arranged in the following order: HY>HX>ZSM-11>ZSM-22 The product distribution depends greatly on the temperature and on the catalyst type. A higher hydrocarbon yields was obtained for HY zeolite catalyst. The selectivity towards high octane number compounds for the proposed catalysts are arranged in the following order: HY>HX>ZSM-11>ZSM-22 The cracking conversion is improved by increasing reaction pressure up to 15 bar. The simulated experiments of the catalytic cracking process show that the higher conversion and more desired products can be achieved to conventional feeds.

Background: To determine whether surgical residency training has influenced the occurrence of common bile duct injuries duringlaparoscopic cholecystectomy, and to assess the anatomic and technical details of bile duct injuries from the practices of surgeons trained in laparoscopic cholecystectomy after residency versus surgeons trained in laparoscopic cholecystectomy during residency. Methods: This was a retrospective study of BDI following cholecystectomy managed in the department of surgery, Al-Hussein Teaching Hospital, from March 2018 to November 2022. The clinical data, severity of BDI, preoperative management, operative management and postoperative outcomes were analyzed. All the cases of BDI following cholecystectomy either open or laparoscopic for cholelithiasis were included in this study. Results : VBIs represent serious and challenging surgical complications and this study finds that acute cholecystitis, hospital type, experience and education level of surgeon are the most significant risk factors in selective set of logistic regression models. Conclusion: Bile duct injury with intact continuity of the duct can be successfully managed with endoscopic stenting of the biliary tree. Intraoperative diagnosis of bile injury and immediate surgical management has good outcome. Similarly, bile duct injury diagnosed after 7 days of surgery can be managed with roux en-y hepatojejunostomy with Hepp- Cauinaud approach after 6 weeks of index surgery following resolution of inflammation with good long term outcome. [ABSTRACT FROM AUTHOR]

A number of aqueous samples were collected from river Tigris in Baghdad city, enriched ~1000 times using solid phase extraction (SPE), then extracted the trace concentrations of some polychlorinated biphenyls (PCB) using an aqueous two-phase system (ATPS) composed of 1Methylpyridinium chloride [MePy]Cl and KH2PO4 salt. High performance liquid chromatography technique coupled with ultraviolet (HPLC-UV) is used for the quantification. Extraction under the optimized conditions of pH, solvent composition, duration and temperature has given with a yield of PCB about 91%. The limit of detection (LOD) and limit of quantification (LOQ) for analyses are 0.11-0.62 µg.L−1 and 2.67–3.43 µg.L−1 respectively with relative standard deviations (RSD) ranging from 2.9-7.6 %. The method can be applied for the analysis of other PCBs and bimolecular traces in aqueous media.