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Polybenzoxazines (PBz) are advanced thermosetting phenolic resins with many advantages, including producing nontoxic by-products, molecular design flexibility, minimum shrinkage, and low water absorption. Nevertheless, some issues might occur when synthesizing PBz, such as their brittleness, which necessitates the incorporation of some additives, such as adding another polymer or some nanocomposite material to enhance the performance of PBz. Polymer nanocomposites have emerged as multifaceted and advanced materials in recent years to overcome the disadvantages of PBz. The development of polymer nanocomposites has broadened the scope of possible uses for coatings and adhesives. Researchers constantly discover new methods for creating polymer nanocomposite coatings. The modification of fillers and the manufacturing processes used determine the properties of polymer nanocomposite coatings. Depending on various features and application types, polymer nanocomposite coatings can be classified into conductive, biocompatible, and intelligent nanocomposite coatings. Nanocomposite adhesives can be classified based on their specific performance features, such as structural, biomimetic, pressure-sensitive, and conductive. The use of newly produced polymer nanocomposites has become increasingly common in several areas of modern technology, including applications such as corrosion protection and accelerated regeneration of biological tissue. The use of polymer nanocomposites has resulted in a substantial revolution in coatings and adhesives. This review aims to shed light and provide information on using polybenzoxazine nanocomposites and their most recent coating implementation. [ABSTRACT FROM AUTHOR]

The soleus H-reflex modulation pattern was investigated during stepping following transspinal stimulation over the thoracolumbar region at 15, 30, and 50 Hz with 10 kHz carry-over frequency above and below the paresthesia threshold. The soleus H-reflex was elicited by posterior tibial nerve stimulation with a single 1 ms pulse at an intensity that the M-wave amplitudes ranged from 0 to 15% of the maximal M-wave evoked 80 ms after the test stimulus, and the soleus H-reflex was half the size of the maximal H-reflex evoked on the ascending portion of the recruitment curve. During treadmill walking, the soleus H-reflex was elicited every 2 or 3 steps, and stimuli were randomly dispersed across the step cycle which was divided in 16 equal bins. For each subject and condition, the soleus M-wave and H-reflex were normalized to the maximal M-wave. The soleus background electromyographic (EMG) activity was estimated as the linear envelope for 50 ms duration starting at 100 ms before posterior tibial nerve stimulation for each bin. The gain was determined as the slope of the relationship between the soleus H-reflex and the soleus background EMG activity. The soleus H-reflex phase-dependent amplitude modulation remained unaltered during transspinal stimulation, regardless frequency, or intensity. Similarly, the H-reflex slope and intercept remained the same for all transspinal stimulation conditions tested. Locomotor EMG activity was increased in knee extensor muscles during transspinal stimulation at 30 and 50 Hz throughout the step cycle while no effects were observed in flexor muscles. These findings suggest that transspinal stimulation above and below the paresthesia threshold at 15, 30, and 50 Hz does not block or impair spinal integration of proprioceptive inputs and increases activity of thigh muscles that affect both hip and knee joint movement. Transspinal stimulation may serve as a neurorecovery strategy to augment standing or walking ability in upper motoneuron lesions. [ABSTRACT FROM AUTHOR]

Background: Chronic hepatitis C (HCV) infection presents global health challenges with significant morbidity and mortality implications. Successfully treating patients with cirrhosis may lead to mortality rates comparable to the general population. This study aims to utilize machine learning techniques to create predictive mortality models for individuals with chronic HCV infections. Methods: Data from chronic HCV patients at Sultan Qaboos University Hospital (2009–2017) underwent analysis. Data pre-processing handled missing values and scaled features using Python via Anaconda. Model training involved SelectKBest feature selection and algorithms such as logistic regression, random forest, gradient boosting, and SVM. The evaluation included diverse metrics, with 5-fold cross-validation, ensuring consistent performance assessment. Results: A cohort of 702 patients meeting the eligibility criteria, predominantly male, with a median age of 47, was analyzed across a follow-up period of 97.4 months. Survival probabilities at 12, 36, and 120 months were 90.0%, 84.0%, and 73.0%, respectively. Ten key features selected for mortality prediction included hemoglobin levels, alanine aminotransferase, comorbidities, HCV genotype, coinfections, follow-up duration, and treatment response. Machine learning models, including the logistic regression, random forest, gradient boosting, and support vector machine models, showed high discriminatory power, with logistic regression consistently achieving an AUC value of 0.929. Factors associated with increased mortality risk included cardiovascular diseases, coinfections, and failure to achieve a SVR, while lower ALT levels and specific HCV genotypes were linked to better survival outcomes. Conclusions: This study presents the use of machine learning models to predict mortality in chronic HCV patients, providing crucial insights for risk assessment and tailored treatments. Further validation and refinement of these models are essential to enhance their clinical utility, optimize patient care, and improve outcomes for individuals with chronic HCV infections. [ABSTRACT FROM AUTHOR]

• Significant intraoperative neuromonitoring changes can predict new neurological deficits after endovascular treatment of ruptured aneurysms. • Intraoperative neurophysiological monitoring (IONM) (intraoperative neurophysiological monitoring) changes can detect postprocedural neurological deficits (PPND) (postprocedural neurological deficit) with sensitivity up to 47.8% and specificity up to 98.9%. • Periprocedural complications and IONM changes are associated with 6 and 20 folds, respectively, increase in risk of PPND. To evaluate the diagnostic accuracy of intraoperative neurophysiological monitoring (IONM) during endovascular treatment (EVT) of ruptured intracranial aneurysms (rIA). IONM and clinical data from 323 patients who underwent EVT for rIA from 2014-2019 were retrospectively reviewed. Significant IONM changes and outcomes were evaluated based on visual review of data and clinical documentation. Of the 323 patients undergoing EVT, significant IONM changes were noted in 30 patients (9.29%) and 46 (14.24%) experienced postprocedural neurological deficits (PPND). 22 out of 30 (73.33%) patients who had significant IONM changes experienced PPND. Univariable analysis showed changes in somatosensory evoked potential (SSEP) and electroencephalogram (EEG) were associated with PPND (p-values: <0.001 and <0.001, retrospectively). Multivariable analysis showed that IONM changes were significantly associated with PPND (Odd ratio (OR) 20.18 (95%CI:7.40–55.03, p-value: <0.001)). Simultaneous changes in both IONM modalities had specificity of 98.9% (95% CI: 97.1%–99.7%). While sensitivity when either modality had a change was 47.8% (95% CI: 33.9%–62.0%) to predict PPND. Significant IONM changes during EVT for rIA are associated with an increased risk of PPND. IONM can be used confidently as a real time neurophysiological diagnostic guide for impending neurological deficits during EVT treatment of rIA. [ABSTRACT FROM AUTHOR]

Background/Objectives: Cholesteatoma presents significant management challenges in otolaryngology. This study aimed to delineate the influence of demographic and clinical characteristics, preoperative imaging, and surgical approaches on treatment success in cholesteatoma management. Methods: A cross-sectional analytical study was conducted at the Otolaryngology Department of the University Hospital from January 2021 to December 2022. It included 68 patients diagnosed with cholesteatoma, focusing on three objectives: assessing the impact of demographic and clinical characteristics on treatment outcomes, evaluating the predictive value of preoperative imaging findings, and analyzing the influence of surgical factors. Results: The study population predominantly consisted of male (56%) and Saudi (81%) patients, with an average age of 45 years. Logistic regression revealed that older age (OR: 1.05), male gender (OR: 0.63), and non-Saudi Arab ethnicity (OR: 2.14) significantly impacted treatment outcomes. Clinical characteristics such as severe disease severity (OR: 3.00) and longer symptom duration (OR: 0.96) also influenced treatment success. In preoperative imaging, labyrinthine fistula (Regression Coefficient: 0.63) and epidural extension (Coefficient: 0.55) emerged as key predictors. The surgical factors that significantly affected the outcomes included the extent of surgery (Complete Removal OR: 3.32) and the use of endoscopic approaches (OR: 1.42). Conclusions: This study highlights that patient demographics, clinical profiles, specific preoperative imaging features, and surgical strategies multifactorially determine cholesteatoma treatment success. These findings suggest the necessity for a tailored approach in cholesteatoma management, reinforcing the importance of individualized treatment plans based on comprehensive preoperative assessments. [ABSTRACT FROM AUTHOR]

A fifth-order nonlinear wave equation (generalized Korteweg–deVries equation) that arises in the theory of thin liquid films is introduced with the odd viscosity by the long-wave approximation regime. The presence of the odd viscosity is considered to be a non-dissipative factor in the evolution of the film flow. Sinusoidal and travelling waves arise in systems with non dissipation and instability. The introduced wave equation includes quadratic and cubic nonlinearities. The linear instability of sinusoidal waves is analyzed. The stability and bifurcation of travelling waves are discussed. [ABSTRACT FROM AUTHOR]

This study presents the successful synthesis of a cesium–nickel–vanadium fluoride (CsNiVF6) pyrochlore nano-sheet catalyst via solid-phase synthesis and its electrochemical performance in green hydrogen production through urea electrolysis in alkaline media. The physicochemical characterizations revealed that the CsNiVF6 exhibits a pyrochlore-type structure consisting of a disordered cubic corner-shared (Ni, V)F6 octahedra structure and nano-sheet morphology with a thickness ranging from 10 to 20 nm. Using the CsNiVF6 catalyst, the electrochemical analysis, conducted through cyclic voltammetry, demonstrates a current mass activity of ~1500 mA mg−1, recorded at 1.8 V vs. RHE, along with low-resistance (3.25 ohm) charge transfer and good long-term stability for 0.33 M urea oxidation in an alkaline solution. Moreover, the volumetric hydrogen production rate at the cathode (bare nickel foam) is increased from 12.25 to 39.15 µmol/min upon the addition of 0.33 M urea to a 1.0 KOH solution and at a bias potential of 2.0 V. The addition of urea to the electrolyte solution enhances hydrogen production at the cathode, especially at lower voltages, surpassing the volumes produced in pure 1.0 M KOH solution. This utilization of a CsNiVF6 pyrochlore nano-sheet catalyst and renewable urea as a feedstock contributes to the development of a green and sustainable hydrogen economy. Overall, this research underscores the potential use of CsNiVF6 as a cost-effective nickel-based pyrochlore electrocatalyst for advancing renewable and sustainable urea electrolysis processes toward green hydrogen production. [ABSTRACT FROM AUTHOR]

In aqueous pH 7 phosphate buffer, during controlled potential electrolysis (CPE) at -1.10 V vs. Ag|AgCl the literature square planar copper complex, [CuIILEt]BF4 (1), forms a heterogeneous deposit on the glassy carbon working electrode (GCWE) that is a stable and effective hydrogen evolution reaction (HER) electrocatalyst. Specifically, CPE for 20 hours using a small GCWE (A = 0.071 cm²) gave a turnover number (TON) of 364, with ongoing activity. During CPE the brownish-yellow colour of the working solution fades, and a deposit is observed on the small GCWE. Repeating this CPE experiment in a larger cell with a larger GCWE (A = 2.7 cm²), connected to a gas chromatograph, resulted in a TON of 2628 after 2.6 days, with FE = 93%, and with activity ongoing. After this CPE, the working solution had faded to nearly colourless, and visual inspection of the large GCWE showed a material had deposited on the surface. In a 'rinse and repeat test', this heterogeneous deposit was used for further CPE, in a freshly prepared working solution minus fresh catalyst, which resulted in similar ongoing HER activity to before, consistent with the surface deposited material being the active HER catalyst. EDS, PXRD and SEM analysis of this deposit shows that copper and oxygen are the main components present, most likely comprising copper and copper(I) oxide ((Cu2O)n) formed from 1. The use of 1 leads to a deposit that is more catalytically active than that formed when starting with a simple copper salt (control), likely due to it forming a more robustly attached deposit, which also enables the observed long-lived catalytic activity. [ABSTRACT FROM AUTHOR]

Natural disasters, like pandemics and earthquakes, are some of the main causes of distress and casualties. Governmental crisis management processes are crucial when dealing with these types of problems. Social media platforms are among the main sources of information regarding current events and public opinion. So, they have been used extensively to aid disaster detection and prevention efforts. Therefore, there is always a need for better automatic systems that can detect and classify disaster data of social media. In this work, we propose enhanced Arabic disaster data classification models. The suggested models utilize domain adaptation to provide state-of-the-art accuracy. We used a standard dataset of Arabic disaster data collected from Twitter for testing the proposed models. Experimental results show that the provided models significantly outperform the previous state-of-the-art results. [ABSTRACT FROM AUTHOR]

This study examines the effect of incorporating olive waste ash (OWA) into high‐strength geopolymer concrete (HSGC) by partially replacing fly ash (FA) and/or granulated blast furnace slag (GBFS) in the presence of rice husk ash (RHA). A total of 18 different mixtures were prepared and divided into three groups: (1) Utilizing OWA as a partial replacement for FA at a weight ratio of 10%–50%. (2) Incorporating OWA as a partial substitute for GBFS, with a weight ratio of 10%–50%. (3) Incorporate OWA as a partial substitute for FA and GBFS, with a recommended weight ratio of 10%–50%. The slump flow test was used to analyze the fresh properties of the HSGC. The hardening properties were examined by measuring the compressive strength, tensile strength, flexural strength, and modulus of elasticity. Furthermore, an analysis was conducted on the water absorbency, sulfate attack, and chloride penetration depth. A scanning electron microscope was used for the microstructural analysis. The inclusion of OWA in HSGC mixtures resulted in a significant enhancement of the compressive strength. Specifically, adding 20% OWA to FA increased the compressive strength by 8.9% at 28 days. Similarly, 30% OWA for GGBS and 30% OWA for GGBS + FA led to compressive strength improvements of 20% and 17.8%, respectively. OWA application resulted in an enhanced microstructure density of the HSGC samples. The ideal substitution ratio varied between 20% and 30% based on weight. [ABSTRACT FROM AUTHOR]

The question of collapse (blow-up) in finite time is investigated for the two-dimensional (non-integrable) space-time nonlocal nonlinear Schrödinger equations. Starting from the two-dimensional extension of the well known AKNS q , r system, three different cases are considered: (i) partial and full parity-time (PT) symmetric, (ii) reverse-time (RT) symmetric, and (iii) general q , r system. Through extensive numerical experiments, it is shown that collapse of Gaussian initial conditions depends on the value of its quasi-power. The collapse dynamics (or lack thereof) strongly depends on whether the nonlocality is in space or time. A so-called quasi-variance identity is derived and its relationship to blow-up is discussed. Numerical simulations reveal that this quantity reaching zero in finite time does not (in general) guarantee collapse. An alternative approach to the study of wave collapse is presented via the study of transverse instability of line soliton solutions. In particular, the linear stability problem for perturbed solitons is formulated for the nonlocal RT and PT symmetric nonlinear Schrödinger (NLS) equations. Through a combination of numerical and analytical approaches, the stability spectrum for some stationary one soliton solutions is found. Direct numerical simulations agree with the linear stability analysis which predicts filamentation and subsequent blow-up. [ABSTRACT FROM AUTHOR]

Functionalized biopolymers, especially at the nanoscale, boast a broad spectrum of applications. In this context, our laboratory synthesized chitosan, an example of such biopolymers, through the deacetylation of chitin derived from shrimp. The molecular structure of the prepared chitosan was examined using FTIR, which confirmed its similarity to commercially available chitosan. A significant aspect of chitosan's functionalization largely hinges on its solubility in major solvents, which in turn affects its potential applications. In this study, the DFT:B3LYP/3-21g* model was employed to investigate the influence of various solvents on the structural and physical properties of chitosan. Key parameters such as the total dipole moment (TDM), HOMO/LUMO energy gap, and molecular electrostatic potential (MESP) were calculated to ascertain the effect of solvation on nanoscale chitosan. The findings suggest that solvation enhances chitosan's reactivity in terms of the TDM, HOMO/LUMO energy gap, and MESP. Additionally, solvation led to minor alterations in chitosan's structural parameters. To experimentally validate the theoretical outcomes, chitosan was dissolved in several solvents. The FTIR spectrum of each solution was then recorded and juxtaposed against raw (undissolved) chitosan. The analyses showed no modifications in the molecular structure due to solvation. [ABSTRACT FROM AUTHOR]

Genome-wide association studies (GWAS) have yielded significant insights into the genetic architecture of myocardial infarction (MI), although studies in non-European populations are still lacking. Saudi Arabian cohorts offer an opportunity to discover novel genetic variants impacting disease risk due to a high rate of consanguinity. Genome-wide genotyping (GWG), imputation and GWAS followed by meta-analysis were performed based on two independent Saudi Arabian studies comprising 3950 MI patients and 2324 non-MI controls. Meta-analyses were then performed with these two Saudi MI studies and the CardioGRAMplusC4D and UK BioBank GWAS as controls. Meta-analyses of the two Saudi MI studies resulted in 17 SNPs with genome-wide significance. Meta-analyses of all 4 studies revealed 66 loci with genome-wide significance levels of p < 5 × 10–8. All of these variants, except rs2764203, have previously been reported as MI-associated loci or to have high linkage disequilibrium with known loci. One SNP association in Shisa family member 5 (SHISA5) (rs11707229) was evident at a much higher frequency in the Saudi MI populations (> 12% MAF). In conclusion, our results replicated many MI associations, whereas in Saudi-only GWAS (meta-analyses), several new loci were implicated that require future validation and functional analyses. [ABSTRACT FROM AUTHOR]

Background: The ophthalmology workforce is an integral component of any health care system. However, the demand for eye care has imposed a heavy burden on this system. Hence, this study aimed to estimate the trends, demographic characteristics, distribution, and variation between Saudi and non-Saudi ophthalmologists and the future challenges of the ophthalmology workforce in the Kingdom of Saudi Arabia (KSA). Methods: This study was conducted in the KSA and included ophthalmologists practicing from 2010 to 2023. From the Saudi Commission for Health Specialties, we obtained the number, gender, nationality, and rank of ophthalmologists. The geographic distribution of ophthalmologists in the KSA was obtained from the Ministry of Health Statistical Yearbook 2021. Results: As of January 2023, the KSA had a total of 2608 registered ophthalmologists, with approximately 81.06 ophthalmologists per 1,000,000 people. Only 38% of all ophthalmologists in the country were Saudis. The percentage of Saudi female graduates increased from 13.3% to 37.2% over 12 years [Sen's estimator of slope for median increase per year = 1.33 (95% CI 1.22–1.57) graduates; trend test P < 0.001). Additionally, we found that the geographic distribution of ophthalmologists varied (test for homogeneity of rates, P < 0.0001), with the larger regions having a higher concentration of ophthalmologists than the smaller regions (75.6 in Riyadh versus 42.8 in Jazan per 1,000,000 people). However, the World Health Organization's target for the ophthalmologist-to-population ratio has been achieved in all 13 health regions of KSA. Conclusion: The recommended ophthalmologist-to-population ratio has been achieved in the KSA, and the number of Saudi ophthalmologists has almost doubled over the past 8 years. However, the majority of ophthalmologists are still non-Saudi, as Saudi ophthalmologists constitute approximately one-third of the ophthalmology workforce in the KSA. The geographical distribution of ophthalmologists varies, which might affect access to care in peripheral regions. In response to the growing demand for eye care in the KSA, several more effective measures might need to be considered. [ABSTRACT FROM AUTHOR]

An important issue in interconnected microgrids (MGs) is the realization of balance between the generation side and the demand side. Imbalanced generation and load demands lead to security, power quality, and reliability issues. The load frequency control (LFC) is accountable for regulating MG frequency against generation/load disturbances. This paper proposed an optimized fractional order (FO) LFC scheme with cascaded outer and inner control loops. The proposed controller is based on a cascaded one plus tilt derivative (1+TD) in the outer loop and an FO tilt integrator-derivative with a filter (FOTIDF) in the inner loop, forming the cascaded (1+TD/FOTIDF) controller. The proposed 1+TD/FOTIDF achieves better disturbance rejection compared with traditional LFC methods. The proposed 1+TD/FOTIDF scheme is optimally designed using a modified version of the liver cancer optimization algorithm (MLCA). In this paper, a new modified liver cancer optimization algorithm (MLCA) is proposed to overcome the shortcomings of the standard Liver cancer optimization algorithm (LCA), which contains the early convergence to local optima and the debility of its exploration process. The proposed MLCA is based on three improvement mechanisms, including chaotic mutation (CM), quasi-oppositional based learning (QOBL), and the fitness distance balance (FDB). The proposed MLCA method simultaneously adjusts and selects the best 1+TD/FOTIDF parameters to achieve the best control performance of MGs. Obtained results are compared to other designed FOTID, TI/FOTID, and TD/FOTID controllers. Moreover, the contribution of electric vehicles and the high penetration of renewables are considered with power system parameter uncertainty to test the stability of the proposed 1+TD/FOTIDF LFC technique. The obtained results under different possible load/generation disturbance scenarios confirm a superior response and improved performance of the proposed 1+TD/FOTIDF and the proposed MLCA-based optimized LFC controller. [ABSTRACT FROM AUTHOR]

Background: Gross domestic product (GDP) serves as a crucial economic indicator for measuring a country's economic growth, exhibiting both linear and non-linear trends. This study aims to analyze and propose an efficient and accurate time series approach for modeling and forecasting the GDP annual growth rate (%) of Saudi Arabia, a key financial indicator of the country. Methodology: Stochastic linear and non-linear time series modeling, along with hybrid approaches, are employed and their results are compared. Initially, conventional linear and nonlinear methods such as ARIMA, Exponential smoothing, TBATS, and NNAR are applied. Subsequently, hybrid models combining these individual time series approaches are utilized. Model diagnostics, including mean absolute error (MAE), root mean square error (RMSE), and mean absolute percentage error (MAPE), are employed as criteria for model selection to identify the best-performing model. Results: The findings demonstrated that the neural network autoregressive (NNAR) model, as a non-linear approach, outperformed all other models, exhibiting the lowest values of MAE, RMSE and MAPE. The NNAR(5,3) projected the GDP of 1.3% which is close to the projection of IMF benchmark (1.9) for the year 2023. Conclusion: The selected model can be employed by economists and policymakers to formulate appropriate policies and plans. This quantitative study provides policymakers with a basis for monitoring fluctuations in GDP growth from 2022 to 2029 and ensuring the sustained progression of GDP beyond 2029. Additionally, this study serves as a guide for researchers to test these approaches in different economic dynamics. [ABSTRACT FROM AUTHOR]

The use of a reflector can increase the solar radiation on the photovoltaic module (PV) surface, whereby the energy output can be improved. However, the economic feasibility may need to be considered too. This study is conducted, for the first time, due to the lack of studies regarding the economic feasibility assessment of implementing reflectors under the Malaysian meteorological conditions. The outcome will give information about the suitability for implementing a PV reflector in Malaysia through an experimental setup at a sewage treatment site, for two months in 2022. The Malaysian meteorological data, which include daily solar radiation, ambient temperature and wind velocity, were collected to study the output energy, efficiency and the economic perspective of a PV. In February 2022, the PV was operating without a reflector and the averaged values for the monthly solar radiation, ambient temperature and wind velocity were 539.9 MJ/m2, 28.4 °C and 2.2 m/s, respectively, which resulted in an output energy of 106.43 kWh. On the other hand, for April 2022, the PV was operating with a reflector. With the respective averaged input parameters 544.98 MJ/m2, 28.9 °C and 1.51 m/s, the output energy was 121.94 kWh. It is thus shown that the PV with a reflector increases the PV's output energy by 14.57%. Also, it is shown that the cost-effective factor value is 0.955 which means that the PV reflector is economically feasible to be implemented under the Malaysian meteorological conditions. Hence, extensive research should be conducted to improve the performance of PV reflectors. The findings of this paper maybe useful for researchers and/or manufacturers of PV reflectors. [ABSTRACT FROM AUTHOR]

This study focuses on developing the production of ultra-high-performance lightweight concrete (UHPLC) by combining pumice with an air-entraining agent. Air-entraining agents of aluminum powder (AP) and lightcrete (LC) were added in amounts of 0.1, 0.2, 0.3, 0.4, and 0.5% by weight of cement to create air bubbles. Crushed pumice has also been used as a partial sand replacement in proportions of 25% and 50% by volume, with or without the addition of AP or LC. To investigate the fresh, mechanical, and microstructural properties, seventeen UHPLC combinations were constructed. A slump flow diameter test was conducted to evaluate the characteristics of fresh UHPLC, and mechanical properties were evaluated by completing dry density, compressive strength, tensile strength, flexural strength, modulus of elasticity, and dry shrinkage tests. The effect of high temperatures of 20, 400, 600, and 800 °C on compressive strength was also investigated. The microstructure characteristics were analyzed using a scanning electron microscope. The research concluded that high-performance concrete with a compressive strength of 127.6 MPa and a dry density of 1970 kg/m3 could be produced after a 28-day age test. This was accomplished by including 0.1% LC by weight of cement and 25% pumice as a partial substitute for sand. The mixture with 50% pumice as a partial replacement for sand and the addition of 0.5% LC of the cement weight exhibited the least loss in compressive strength when subjected to high temperatures. [ABSTRACT FROM AUTHOR]

A frequency/phase/amplitude estimator is arguably one of the most crucial components in the control and synchronization of grid-connected equipment. Such an estimator may also be useful for monitoring and protection purposes in power systems. In this paper, an open-loop (and therefore unconditionally stable) estimator for the accurate and rapid extraction of the grid voltage phase, frequency, and amplitude is presented. In designing the proposed technique, special focus is given to applications operating at a low sampling rate. Examples of such applications include high-power converters, where both switching and sampling frequencies are very low. The study concludes with a comprehensive evaluation of the proposed estimator, demonstrating its effectiveness in accurately and swiftly estimating the fundamental parameters of grid voltage under low sampling rates. It highlights the estimator's enhanced performance in scenarios of distorted grid conditions and its superiority in filtering capabilities compared to traditional methods. These findings underline the estimator's potential for broad applicability in power system monitoring, protection, and control. [ABSTRACT FROM AUTHOR]

Motor vehicle accidents are a significant cause of morbidity and mortality worldwide. Airbags aim to reduce the severity of motor vehicle accidents, but their deployment is not without risks. This study presents five cases presenting with diverse forms of upper extremity injuries following airbag deployment. The presented cases highlight the variety of clinical presentations, the differences in diagnostics in terms of imaging modalities, as well as the spectrum of possible outcomes from complete healing to decreased range of motion to persistent neurological symptoms. Understanding the mechanisms and presentations of such injuries can only help in improving and creating new strategies for the prevention of such injuries, as well as their management. [ABSTRACT FROM AUTHOR]

Background: Early identification of a patient with infection who may develop sepsis is of utmost importance. Unfortunately, this remains elusive because no single clinical measure or test can reflect complex pathophysiological changes in patients with sepsis. However, multiple clinical and laboratory parameters indicate impending sepsis and organ dysfunction. Screening tools using these parameters can help identify the condition, such as SIRS, quick SOFA (qSOFA), National Early Warning Score (NEWS), or Modified Early Warning Score (MEWS). We aim to externally validate qSOFA, SIRS, and NEWS/NEWS2/MEWS for in-hospital mortality among adult patients with suspected infection who presenting to the emergency department. Methods and analysis: PASSEM study is an international prospective external validation cohort study. For 9 months, each participating center will recruit consecutive adult patients who visited the emergency departments with suspected infection and are planned for hospitalization. We will collect patients' demographics, vital signs measured in the triage, initial white blood cell count, and variables required to calculate Charlson Comorbidities Index; and follow patients for 90 days since their inclusion in the study. The primary outcome will be 30-days in-hospital mortality. The secondary outcome will be intensive care unit (ICU) admission, prolonged stay in the ICU (i.e., ≥72 hours), and 30- as well as 90-days all-cause mortality. The study started in December 2021 and planned to enroll 2851 patients to reach 200 in-hospital death. The sample size is adaptive and will be adjusted based on prespecified consecutive interim analyses. Discussion: PASSEM study will be the first international multicenter prospective cohort study that designated to externally validate qSOFA score, SIRS criteria, and EWSs for in-hospital mortality among adult patients with suspected infection presenting to the ED in the Middle East region. Study registration: The study is registered at ClinicalTrials.gov (NCT05172479). [ABSTRACT FROM AUTHOR]

\nHIGHLIGHTSThis study explores a new electrode configuration for measuring the void fraction of two-phase flows using capacitance-based sensors. The proposed method is considered ‘skewed’ because of its unique geometric shape, and the performance of the proposed sensor was evaluated and improved via multiple simulations using the COMSOL Multiphysics software. The simulations encompass three different flow patterns, stratified, annular and homogeneous, whose performance themselves were verified in a previous study. The influences of geometric properties and parameters on the sensitivity of the proposed sensor were evaluated to determine an optimal configuration. Furthermore, the sensitivity distribution on different void fractions of the sensor was analysed for various void fractions in different flow patterns. Additionally, the proposed configuration was also compared alongside double-ring and concave sensors to determine the overall sensitivity. At 2.11 pF, the overall sensitivity of the proposed sensor was significantly higher than that of the other sensors. It is worth mentioning that the measurement precision of multiphase flow meters is of high importance, particularly in petroleum industry because of the oil price and also the high amount of transported products. This study explores a new electrode configuration for measuring void fraction of two-phase flows using capacitance-based sensorsThe COMSOL simulations encompass three different flow patterns: stratified, annular and homogeneousThe influences of geometric properties and parameters on the sensitivity of the proposed sensor were evaluated to determine an optimal configurationSensitivity distribution of the sensor was analysed for various void fractions in different flow patternsThe proposed configuration was also compared alongside double-ring and concave sensors to determine the overall sensitivityAt 2.11 pF, the overall sensitivity of the proposed sensor was significantly higher than that of the other sensorsThis study explores a new electrode configuration for measuring void fraction of two-phase flows using capacitance-based sensorsThe COMSOL simulations encompass three different flow patterns: stratified, annular and homogeneousThe influences of geometric properties and parameters on the sensitivity of the proposed sensor were evaluated to determine an optimal configurationSensitivity distribution of the sensor was analysed for various void fractions in different flow patternsThe proposed configuration was also compared alongside double-ring and concave sensors to determine the overall sensitivityAt 2.11 pF, the overall sensitivity of the proposed sensor was significantly higher than that of the other sensors [ABSTRACT FROM AUTHOR]

Background: Nurses play a vital role in providing round-the-clock care to patients, but the challenges associated with working night shifts can have significant implications for their well-being and quality of life. Methods: This cross-sectional study aimed to investigate the impact of night shift stress and sleep disturbance on the quality of life among nurses working in Palestine Red Crescent Society and Al-Ahli Hospital. Convenience sampling was used to recruit 189 full-time registered nurses with at least one year of job experience. The participants completed a questionnaire assessing night shift stress, sleep disturbance, and quality of life. Descriptive statistics, correlation analysis, and path analysis were conducted to analyze the data. Results: The results reveal that quality of life has positive and low relationship with both night shift stress and sleep disturbances. Results also reveal that night shift stress had a direct negative impact on the quality of life of nurses. Sleep disturbance was found to mediate the relationship between night shift stress and quality of life, indicating that higher levels of night shift stress were associated with increased sleep disturbance, which, in turn, led to poorer quality of life outcomes. Conclusion: These findings highlight the importance of addressing night shift stress and sleep disturbance among nurses to enhance their well-being and improve the quality of care provided to patients. In conclusion, this study contributes to the existing literature by demonstrating the detrimental effects of night shift stress and sleep disturbance on the quality of life of nurses. It emphasizes the importance of implementing interventions and creating supportive work environments that address the unique challenges faced by nurses working night shifts. [ABSTRACT FROM AUTHOR]

Extraskeletal Ewing sarcomas (EES) is a rare, aggressive malignancy that typically affects adolescents or young adults, primarily involving the deep soft tissues of the lower extremities and paravertebral regions. The occurrence of EES in the pancreas is even rarer. These tumors are characterized by small, round cell sarcomas displaying varying degrees of neuroectodermal differentiation, as revealed through light, electron microscopy, or immunohistochemistry. Diagnosing EES demands a high level of suspicion. Histopathologically, the presence of small round cell tumors in the pancreas, along with CD99 positivity in immunohistochemistry, assists in diagnosing EES. Molecular analysis demonstrating EWSR1 (22q12) rearrangement via interface fluorescence in situ hybridization is required to confirm the diagnosis. A comprehensive review of pancreatic EES cases revealed that the primary treatment modality typically involves surgical intervention, often complemented by chemotherapy and, in some cases, radiotherapy. In this report, we describe the case of a 28-year-old male presenting with abdominal pain and a loss of appetite, which, upon histopathological and molecular examination, was identified as EES of the pancreas. The patient underwent surgical resection of the pancreatic mass, followed by omentum, splenectomy, and chemotherapy. EES is a highly aggressive tumor with an insidious onset, and patients usually exhibit non-specific clinical symptoms. Although exceedingly rare, it should be considered in the differential diagnosis of pancreatic masses. [ABSTRACT FROM AUTHOR]

This work uses the Green function to model the emission spectra from a hybrid metal nanoparticle (MNP) coupled with a double quantum dot (DQD), considering higher-order plasmonic mode contribution. It calculates the quantum dot (QD) energy states and momenta, i.e., this work differs from other strong-coupling systems by considering the material entities. A Fano-shape spectrum is shown with peaks depending on interference between the fields with the DQD and MNP. A prominent effect of the pump field appears as it interferes with other fields (probe and MNP polarization field). The MNP–DQD distance and MNP radius control the peak height and its position in the spectrum. The importance of the probe field in controlling the peak frequency and its height is demonstrated. The transition energy with momenta controls the spectra. An approximated relation is presented. High strength in the DQD–MNP and a more strong contribution are obtained compared to QD–MNP. [ABSTRACT FROM AUTHOR]

When scale builds up in a transmission pipeline, it narrows the pipe's interior and causes losses in both power and efficiency. A noninvasive instrument based on gamma-ray attenuation is one of the most reliable diagnostic procedures for determining volumetric percentages in a variety of circumstances. A system with a NaI detector and dual-energy gamma generator simulations (241Am and 133 Ba radioisotopes) is recommended for simulating a volume percentage detection system utilizing Monte Carlo N particle (MCNP). Three-phase flow consisting of oil, water, and gas moves through a scaled pipe of variable wall thicknesses in a stratified flow regime with changing volume percentages. After gamma rays are emitted from one end of the pipe, a detector take in the photons coming from the other end. Four temporal features, including kurtosis and mean value of the square root (MSR), skewness, and waveform length (WL) picked up by the detector, were thus obtained. By training two GMDH neural networks with the aforementioned inputs, it is possible to forecast volumetric percentages with an RMSE of less than 0.90 and independently of scale thickness. The low error value, simplicity of the system, and reduction of design costs ensures the effectiveness of the suggested method and the advantages of employing this approach in the petroleum and petrochemical industries. [ABSTRACT FROM AUTHOR]

Combined Heat and Power Units Economic Dispatch (CHPUED) is a challenging non-convex optimization challenge in the power system that aims at decreasing the production cost by scheduling the heat and power generation outputs to dedicated units. In this article, a Kepler optimization algorithm (KOA) is designed and employed to handle the CHPUED issue under valve points impacts in large-scale systems. The proposed KOA is used to forecast the position and motion of planets at any given time based on Kepler's principles of planetary motion. The large 48-unit, 96-unit, and 192-unit systems are considered in this study to manifest the superiority of the developed KOA, which reduces the fuel costs to 116,650.0870 USD/h, 234,285.2584 USD/h, and 487,145.2000 USD/h, respectively. Moreover, the dwarf mongoose optimization algorithm (DMOA), the energy valley optimizer (EVO), gray wolf optimization (GWO), and particle swarm optimization (PSO) are studied in this article in a comparative manner with the KOA when considering the 192-unit test system. For this large-scale system, the presented KOA successfully achieves improvements of 19.43%, 17.49%, 39.19%, and 62.83% compared to the DMOA, the EVO, GWO, and PSO, respectively. Furthermore, a feasibility study is conducted for the 192-unit test system, which demonstrates the superiority and robustness of the proposed KOA in obtaining all operating points between the boundaries without any violations. [ABSTRACT FROM AUTHOR]

Considering the alarming increase in cyberattacks and their potential financial implications, the importance of cybersecurity education and training cannot be overstated. This paper presents a systematic literature review that examines different cybersecurity education and training techniques with a focus on symmetry. It primarily focuses on traditional cybersecurity education techniques and emerging technologies, such as virtual reality (VR) and augmented reality (AR), through the lens of symmetry. The main objective of this study is to explore the existing cybersecurity training techniques, identify the challenges involved, and assess the effectiveness of cybersecurity training based on VR and AR while emphasizing the concept of symmetry. Through careful selection criteria, 66 primary studies were selected from a total of 150 pertinent research studies. This article offers valuable insights into the pros and cons of conventional training approaches, explores the use of VR and AR in cybersecurity education concerning symmetry, and thoroughly discusses the challenges associated with these technologies. The findings of this review contribute significantly to the continuing efforts in cybersecurity education by offering recommendations for improving employees' knowledge, engagement, and motivation in cybersecurity training programs while maintaining symmetry in the learning process. [ABSTRACT FROM AUTHOR]

The current study evaluates the cytotoxicity, mode of cell death and chemical analysis of selected beauty products and evaluation of the protective effect of Tamarix articulata (TA) extract against toxicity induced by beauty products in skin fibroblasts (Hs27). MTT and Crystal violet (CV) assays were used to determine the dose-dependent cytotoxic effects of beauty products against Hs27 fibroblasts. DNA fragmentation assay and annexin-V staining were conducted to determine the mode of cell killing induced by evaluated beauty products. Quantification of reactive oxygen species (ROS) and antioxidant enzyme levels were used to evaluate the oxidative stress. Chemical analysis and heavy metals were evaluated to determine beauty products. Pre-treatment with TA extract for different time points followed by time-dependent exposure with beauty products to assess the protective effect of TA extract in Hs27 cells was analyzed by MTT and CV assays. Owing to the presence of various harmful heavy metals such as arsenic (As), chromium (Cr), cadmium (Cd), nickel (Ni), and lead (Pb) in beauty products, our results revealed that all beauty products induce significant cytotoxicity over time (1, 4 h) in a dose-dependent (125, 250, 500 μg/mL) manner. DNA fragmentation assay, quantification of apoptosis by annexin-V staining, determination of ROS and antioxidant enzymes (CAT, GSH-Px and SOD) revealed that the induced cytotoxicity was caused by oxidative stress-mediated apoptosis. However, pre-incubation with a safe dose (50 μg/mL) of TA for different times (24, 48 h) followed by exposure to various doses (62.5, 125, 250, 500 μg/mL) of beauty products for different times (1, 4 h) revealed significant (*p≤0.05, **p≤0.01) protection against beauty product-mediated cytotoxicity. The effect was more pronounced for 1 h exposure to beauty products compared to 4 h. Our study demonstrates that the due to the presence of heavy metals in synthetic beauty products exhibit marked toxicity to skin fibroblasts due to oxidative stress-mediated apoptosis. However, the presence of abundant bioactive polyphenols with promising antiscavenging activity in TA extracts significantly nullifies cytotoxicity promoted by examined beauty products in skin fibroblasts (Hs27). [ABSTRACT FROM AUTHOR]

Background: Total joint arthroplasty (TJA) can be associated with the development of periprosthetic joint infection (PJI). It is necessary to determine the modifiable and non-modifiable risk factors of PJI to provide optimum healthcare to TJA candidates. Methods: This single-center retrospective review investigated 1198 patients who underwent TJA from 2012 to 2022. The data analysis comprised two stages. The first stage was a descriptive analysis, while the second stage was a bivariate analysis. The sociodemographic data, medical history, operative details, and presence of PJI postoperatively were evaluated. Results: The study sample consisted of 1198 patients who underwent TJA. The mean patient age was 63 years. Among the patients, only 1.3% had PJI. No comorbidity was significantly related to PJI. General anesthesia was used in almost 21% of the patients and was significantly associated with a higher risk of infection (p = 0.049). An increased operative time was also significantly related to PJI (p = 0.012). Conversely, tranexamic acid (TXA) administration was a protective factor against PJI (p = 0.017). Conclusion: Although PJI is not a common complication of TJA, multiple risk factors such as general anesthesia and prolonged operative time play a significant role in its development. In contrast, TXA administration is thought to reduce the risk of PJI effectively. [ABSTRACT FROM AUTHOR]

The symbiotic association between fungus-gardening termites Macrotermes and its fungal symbiont has a moderate degree of specificity--although the symbiotic fungi (Termitomyces) form a monophyletic clade, there is not a one-to-one association between termite species and their fungus-garden associates. Here, we aim to determine the origin and phylogenetic relationships of Termitomyces in Oman. We used sequences of the internal transcribed spacer region (ITS) and the nuclear large subunit ribosomal RNA (LSU rRNA, 25S) gene and analyzed these with sequences of Termitomyces from other geographic areas. We find no evidence for more than a single colonization of Oman by Termitomyces. Unexpectedly, we find Termitomyces in Oman is most closely related to the symbiont of M. subhyalinus in West Africa rather than to those of geographically closer populations in East Africa. [ABSTRACT FROM AUTHOR]

Background: Total joint arthroplasty (TJA) can be associated with the development of periprosthetic joint infection (PJI). It is necessary to determine the modifiable and non-modifiable risk factors of PJI to provide optimum healthcare to TJA candidates. Methods: This single-center retrospective review investigated 1198 patients who underwent TJA from 2012 to 2022. The data analysis comprised two stages. The first stage was a descriptive analysis, while the second stage was a bivariate analysis. The sociodemographic data, medical history, operative details, and presence of PJI postoperatively were evaluated. Results: The study sample consisted of 1198 patients who underwent TJA. The mean patient age was 63 years. Among the patients, only 1.3% had PJI. No comorbidity was significantly related to PJI. General anesthesia was used in almost 21% of the patients and was significantly associated with a higher risk of infection (p = 0.049). An increased operative time was also significantly related to PJI (p = 0.012). Conversely, tranexamic acid (TXA) administration was a protective factor against PJI (p = 0.017). Conclusion: Although PJI is not a common complication of TJA, multiple risk factors such as general anesthesia and prolonged operative time play a significant role in its development. In contrast, TXA administration is thought to reduce the risk of PJI effectively. [ABSTRACT FROM AUTHOR]

Background: Chronic liver disease and cirrhosis contribute significantly to global mortality, with limited improvements despite medical advancements. This study aims to evaluate acute decompensation of liver cirrhosis characteristics, etiology, and survival outcomes in Oman. In addition, we examined the accuracy of prognostic scores in predicting mortality at 28 and 90 days. Methods: We conducted a retrospective analysis of 173 adult patients with acute decompensation of liver cirrhosis at Sultan Qaboos University Hospital in Oman. We collected demographic, clinical, and biochemical data, including etiology, prognostic scores (CTP, MELD-Na, CLIF-C), and health outcomes. Results: Alcohol (29.5%), hepatitis C (27.75%), and hepatitis B (26.74%) were the predominant causes of liver cirrhosis in our cohort. Hepatic encephalopathy, mechanical ventilation, and admission to the intensive care unit were strongly associated with an increased mortality rate. The 1-year readmission rate stood at 42.2%. Liver transplantation was performed in 4.1% of cases. The overall mortality rate was approximately 40% during the follow-up period, and the cumulative 28-days and 90-days mortality rates were 20.8% and 25.4%, respectively. Prognostic scores (CTP, MELD-Na, CLIF-C) effectively predicted 28- and 90-day mortality, with CLIF-C demonstrating superior performance (AUROC 0.8694 ± 0.0302 for 28-day mortality and AUROC 0.8382 ± 0.0359 for 90-day mortality). Conclusion: Alcohol and viral hepatitis are the leading causes of liver cirrhosis in our study. Hepatic encephalopathy is a significant predictor of poor outcomes. Prognostic scores (CTP, MELD-Na, CLIF-C) have valuable predictive abilities for short-term mortality. These findings highlight the importance of public strategies to reduce alcohol consumption and the need for the comprehensive management of liver cirrhosis in Oman. Early diagnosis and intervention can improve clinical outcomes and support the establishment of a national organ transplantation program to address the healthcare challenge effectively. [ABSTRACT FROM AUTHOR]

An improved design optimization method for fractional-order-based proportional integral derivative (FOPID) controllers is proposed in this paper to enhance the stability and transient response of automatic voltage-regulator systems. The FOPID represents a higher degree-of-freedom controller through having five tunable parameters, compared with only three parameters in the integer-order PID controller. In the literature, the performance of the FOPID is highly determined through the design method and its parameter-determination process. Recently, optimum design of the FOPID has found wide employment in several engineering applications through using metaheuristic optimization algorithms. In this paper, an improved method for the FOPID's parameter optimization is proposed for AVR applications using the marine predator optimization algorithm (MPA). The proposed MPA–FOPID controller is verified through comparing its performance with other featured and newly developed optimization algorithms. The proposed MPA–FOPID comparative analysis has been proven to have better stability, frequency response, robustness, faster response, and disturbance-rejection ability over the other studied methods in this paper. [ABSTRACT FROM AUTHOR]

A new species, Leiurus hadb Al-Qahtni, Al-Salem, Alqahtani & Badry, sp. nov., is described and illustrated from the Majami al-Hadb Protected Area in the Riyadh Province of Saudi Arabia. The new species is compared with species of Leiurus distributed in Saudi Arabia, especially L. arabicus Lowe, Yağmur & Kovařík, 2014. The integrated results indicate that the population found in Majami al-Hadb represents a distinct species, which is described herein. Moreover, the molecular analysis is conducted on the mitochondrial gene 16S rRNA to compare L. hadb sp. nov. with samples of L. arabicus and L. haenggii from Saudi Arabia. The analysis revealed a genetic divergence ranging from 6.0 to 12%. The combination of molecular evidence and morphological characteristics provides adequate support for recognizing the Majami al-Hadb population as a distinct species. Additionally, an identification key for the genus Leiurus found in Saudi Arabia is also provided. [ABSTRACT FROM AUTHOR]

INTRODUCTION There is a paucity of studies on e-cigarette use among adults with chronic lung disease. In the present study, we aimed to assess whether psychosocial or cognitive factors elucidate the relationship between chronic lung disease (CLD) and susceptibility to e-cigarette use and whether the relationship between CLD and e-cigarette use is conditional on the presence of respiratory symptoms. METHODS We recruited adults aged ≥18 years in Alabama with CLD from university medical clinics (n=140) and individuals without CLD (n=123 as a reference group). Information on sociodemographics, susceptibility to e-cigarette use, psychosocial factors, and cognitive factors were collected. Mediation analysis was used to assess whether the psychosocial factors or cognitive factors explained the association between CLD and susceptibility to using e-cigarettes, and moderation analysis was conducted to determine if respiratory factors would change the association between CLD and susceptibility to e-cigarette use. RESULTS Psychosocial factors (stress, depression, anxiety) and e-cigarette positive expectancy were notably high among individuals with CLD. Having CLD was associated with a lower likelihood of susceptibility to e-cigarette use. Higher levels of stress, being a smoker, boredom, taste/sensorimotor manipulation, and social facilitation were associated with higher odds of susceptibility to using e-cigarettes among individuals with CLD. Mediation analysis indicated a statistically significant indirect effect of CLD on the susceptibility to using e-cigarettes through stress and boredom reduction. We did not find a statistically significant interaction between CLD and respiratory symptoms affecting susceptibility to using e-cigarettes. CONCLUSIONS Individuals with CLD often exhibit stress, depression, and a positive view of e-cigarettes but are generally less inclined to use them. Stress, smoking habits, boredom, taste, and social influence can increase their susceptibility to e-cigarette use. Our findings call for further exploration to evaluate the temporal relationship between CLD status, psychosocial factors, cognitive factors, and susceptibility to using e-cigarettes. [ABSTRACT FROM AUTHOR]

With continuous and rapid change in both technology and businesses due to climate change and governments regulations, Green Supply Chain Management (GSCM) is receiving increasing attentions during last two decades. GSCM refers to the abilities of businesses to enhance operations and sustain environment at the same time and efficiently. In this paper, a comprehensive review of GSCM development and applications is conducted. This review aims to explore the recent developments of GSCM and necessity of adoption GSCM applications in businesses to insure sustainable development. First, a descriptive analysis of 796 paper adopted from Scopus database was conducted to review research on GSCM. Next, a bibliometric analysis of 235 paper was conducted to determine the recent trends and areas of GSCM and related keywords by using VOSviewer software. Then, a content analysis was carried out of 53 review papers by adopting WordStat software to analyze the impact of GSCM on related subjects and trends of GSCM. Finally, a summary analysis of GSCM advantages and challenges was conducted based on fundamental GSCM's objectives. Results reveal that researches on GSCM are in upward curve with limitations in implementing GSCM applications due to high cost, and lack of sufficient experiences. Results also reveal positive moderate correlation of GSCM with environment, performance, sustainability and management practices indicating the limited implementation of GSCM applications. To further explore these limitations, this study summarized the recent challenges and future potential directions of GSCM in both businesses and environments. [ABSTRACT FROM AUTHOR]

The Greco-Roman stucco masks are of great historical, artistic and religious importance. According to the restoration-conservation strategies, the detailed mineral characterization of artifacts is an important step that facilitates the selection of appropriate restoration procedures. Different characterization techniques such as USB digital microscope, scanning electron microscopy-energy dispersive X-ray analysis, X-ray diffraction analysis (XRD), thermal analysis (DTA/DTG), Fourier transform infrared and micro-Raman spectroscopies were used. The results indicated that gypsum is the main component of the stucco mask. As well, calcite was found as an impurity or an addition together with halite and anhydrite as deterioration products. The iron nail corrosion was the reason for a notable discoloration to the stucco mask. FTIR analysis confirms that animal glue is the adhesive material used for the reassembly of the mask. The used pigments for painting the mask are hematite for red-orange color, mixture of hematite and magnetite for brown color and mixture of gypsum and hematite for the white brown color. [ABSTRACT FROM AUTHOR]

The east–west electric field and the characterized horizontal configuration of the geomagnetic fields around the equatorial region cause electron redistribution in the ionospheric bottomside F- region. This electric field E in turn causes the flow of current in a narrow band around this region called Equatorial Electrojet (EEJ) current. The paper discusses the robust least square modelling approach for modelling some selected ionospheric profile parameters below the maximum height of the F2 layer from the computed EEJ values at Jicamarca station (12°S, 76.9 °W) in the Southern American sector and Ilorin (8.50°N, 4.68°E) in the West African sector. The modelled parameters are the maximum electron density, NmF2, the maximum height, hmF2 and the thickness parameter, B0 of the F2- layer which were then compared with the recent ionospheric international standard model (IRI-2016). The proposed new model for ionospheric parameters based on ground-based magnetic field data at specific locations improved the model fit for hmF2 with RMSE value ∼ 30 km, an improvement to the IRI hmF2 model options. In addition, the derived NmF2 model performs poorly as compared to the IRI URSI and CCIR model options for NmF2. The model was however able to reproduce the temporal changes in the NmF2, for example, the semi-annual variation in the observational NmF2 value. The specific local features that were not fully reproduced in the IRI B0 model options can be seen in the derived model. [ABSTRACT FROM AUTHOR]

Lorlatinib (LOR) is a third-generation anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor drug. The Food and Drug Administration (FDA) has granted an approval for the use of LOR as a first therapeutic intervention for individuals diagnosed with ALK-positive metastatic and advanced non-small-cell lung cancer (NSCLC). The present study outlines, for the first time, the development and validation of an innovative microwell-based spectrofluorimetric (MW-SFL) method for the quantification of LOR. The proposed method involved the enhancement of the weak native fluorescence of LOR by its micellization into the sodium lauryl sulfate (SLS) micelles. The procedures of the method were conducted in white opaque plates with 96 microwells, and the enhanced fluorescence signals were measured by a fluorescence plate reader at 405 nm after excitation at 310 nm. The measured relative fluorescence intensity (RFI) had a linear relationship with LOR concentrations in the range of 60–1600 ng mL−1. The limit of detection (LOD) and the limit of quantification (LOQ) were found to be 19 and 56 ng mL−1, respectively. The method's accuracy and precision were assessed using a recovery study; the recovery values ranged from 99.98% to 101.40%, accompanied by relative standard deviation (RSD) values of 0.42% to 1.59%. The proposed MW-SFL method combined the advantages of the intrinsically high sensitivity of the spectrofluorimetric measurement and the excellent throughput of the microwell-based approach. The results proved the method is effective in the determination of LOR in its pharmaceutical tablets, tablet dissolution testing, as well as in spiked urine with a high degree of precision and accuracy. The MW-SFL method is notable for its simple procedures and utilization of water as a solvent, as well as minimal quantities of sample solutions. These features align with its ecofriendly approach to green chemistry principles. These advantages gave the proposed MW-SFL method a high potential value for the determination of LOR in clinical and quality control laboratories. [ABSTRACT FROM AUTHOR]

The presence of pharmaceutical compounds in the environment is problem for human health worldwide. Paracetamol is one of the pharmaceutical compounds that is widely used as a pain reliever and fever reducer, and it has been discharged in water via industrial and domestic wastewater. This study aimed to improve the removal of paracetamol from aqueous solutions using two different amino-acid-modified mesoporous silica nanoparticles (MSNs). Two types of adsorbents were used: the surfaces of epoxy-modified MSNs were modified with glycine (MSN-Gly) and cysteine (MSN-Cys). Topographical images indicated that the size of fabricated nanoparticles ranged between 220 and 360 nm, with a pore size of ~5 nm. IR spectra confirmed the successful attachment of amino acids on MSN surfaces as a peak appeared at ~1720 cm−1, indicating a carbonyl group. A series of experiments were performed using the batch adsorption method to investigate the effects of contact time, initial concentration of the adsorbate, and pH on the removal of paracetamol from the aqueous solution. The adsorption capacity of paracetamol was higher in acidic media for both adsorbents. The maximum adsorbed amount of paracetamol was 300 mg/g for MSN-Gly compared with 250 mg/g for MSN-Cys. For both adsorbents and at all pH values, the experimental data were well matched with the pseudo-second order and the adsorption isotherm was fitted using a Temkin model. [ABSTRACT FROM AUTHOR]