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Anticorrosion coatings are specialized products designed to protect metal surfaces from costly and dangerous corrosion, acting as barriers against corrosive organisms. Therefore, this study examined the physical and mechanical properties of epoxy resin in the presence of reactive diluents. Reactive diluents were synthesized based on styrene (St) and glycidyl methacrylate (GMA) through the free radical method using benzoyl peroxide (BPO) as a catalyst with various feed ratios of St and GMA. Diluents were characterized by Fourier Transform Infrared (FTIR) spectroscopy and Thermogravimetric Analyzer (TGA). Epoxy resins and hardener were at a ratio of 1:1, 1:0.5, and 1:0.3, respectively. The results showed that reactive diluents [Poly(St-co-GMA)] had an excellent dilution effect on epoxy resin with a decrease in epoxy resin viscosity from 8592 mPa-s to 1656, 680, and 430 mPa-s. Furthermore, the adhesion, tensile, and hardness properties contained 70% GMA and 30% St at a hardener ratio of 1:0.3. The increase in the mechanical properties was attributed to the reaction between modified epoxy resins with hardener.

Background & aim: Restless legs syndrome (RLS) is characterized by an uncomfortable urge to move the legs while at rest, relief upon movement or getting up to walk, and worsened symptom severity at night. Studies show that diabetic patients are at high risk of developing RLS and Studies have indicated a high risk of RLS development in diabetic patients, with an established association between RLS and diabetes. RLS has not been investigated in prediabetic patients; Therefore, the aim of the present study was to investigate RLS in prediabetic patients and its relationship with sleep quality, to help improvement of the patient's symptoms and blood sugar control by identifying sleep disorders related to RLS and managing it. Methods: The present cross-sectional study was conducted on 166 patients meeting inclusion criteria in Yasuj, Iran in 2023. Participants completed the International Restless Legs Syndrome (IRLS) and Pittsburgh Sleep Quality Index (PSQI) questionnaires administered by the researcher. Data analysis was performed using descriptive and analytical statistics through the SPSS software Results: The mean age of the patients in the present study was 46.23 ± 11.68 years and ranged from 21 to 75 years. 96 (57.8%) were women and 70 (42.2%) were men. The average of RLS score in the examined patients was 6.54 ± 3.05 and ranged from 0 to 35. It was also shown that 68.07% had no symptoms of RLS. Therefore, the prevalence of RLS in pre-diabetic patients was 31.93%. Gender did not significantly affect RLS scores (P=0.951) and there was no significant difference in the severity of RLS between men and women (P=0.097). The mean of the sleep quality score in the investigated patients was 6.25 ± 4.00 and ranged from 0 to 17. It was also shown that 41% had sleep disorders and there was no significant difference between score of sleep quality in men and women (P=0.168). There was no significant difference between men and women having or not having sleep disorders (P=0.240). The results showed that there was a significant and positive relationship between the severity of RLS and sleep disorder. (P Conclusion: The results of the study indicated a direct and significant relationship between RLS and sleep quality disorders in prediabetic patients.

This study examines the combined impact of pre-test curing and soaking periods on the soil's resistance to collapse those results from treating gypseous sand with varying amounts of nanoclay. The soil comes from the Iraqi city of Najaf. The soil sample is mainly sand. The nanoclay named "Montmorillonite K10" is used, and it is non-toxic. The tests are performed with a computerized Oedometer. The collapse potential is estimated according to a single Oedometer test (SOT), where the specimens are initially dry and then soaked under a stress level of 200 kPa. Four data sets related to the percentages of 0, 3, 6, and 12% nanoclay are used. Each data set comprises three groups of pre-tests for curing duration and different soaking durations. All experiments have a constant initial dry density of 1.64 g/cm3, water moisture of 3%, and gypsum content of 29%. The findings of this study show that the collapse potential (CP) of natural soil specimens decreases as the pre-test curing time increases. Generally, there is a decrease in CP due to adding the nanoclay and 6% of the nanoclay exhibited the highest reduction in CP. Also, there is an increase in the pre-test curing for the nanoclay-treated soil specimens, which leads to an increase in the CP related to the no-curing state.

Due to the increasing demand in construction and use of different types of piles on the one hand and the high cost of conducting large-scale tests on different types of piles, on the other hand, new methods have been proposed to study the behavior of different types of piles. Physical modeling provides the researcher the capability of studying model piles in the scaled environment at low costs. Among the different methods of physical modeling, the use of frustum confining vessels (FCV) has gained attraction in recent years. FCV is a cone-shaped vessel that can produce a stress distribution similar to the idealized linear stress distribution in depth. Helical piles are common types of deep foundations which were first used about 200 years ago. Helical Apiles are driven to the soil by applying a torque to the end of piles in the presence of vertical loads. Their quick and noise-free installation method, the minimal disturbance during the installation, and environmental compatibility make them popular for working in urban areas. In this research, using the finite element method, the optimal dimensions of FCV apparatus were selected, and the FCV apparatus with optimal dimensions were constructed. A total of 18 compression tests were performed on Anzali sand in different relative densities and moisture contents, using single-helix and three-helices piles. Results indicate that increasing the number of helices and relative density of soil increases the pile and sand contact and causes higher bearing capacity for helical piles. Soil saturation, on the other hand, significantly reduces the ultimate strength.

The currently available treatments for inner ear disorders often involve systemic drug administration, leading to suboptimal drug concentrations and side effects. Cochlear implants offer a potential solution by providing localized and sustained drug delivery to the cochlea. While the mechanical characterization of both the implants and their constituent material is crucial to ensure functional performance and structural integrity during implantation, this aspect has been mostly overlooked. This study proposes a novel methodology for the mechanical characterization of our recently developed cochlear implant design, namely, rectangular and cylindrical, fabricated using two-photon polymerization (2 PP) with a novel photosensitive resin (IP-Q™). We used in silico computational models and ex silico experiments to study the mechanics of our newly designed implants when subjected to torsion mimicking the foreseeable implantation procedure. Torsion testing on the actual-sized implants was not feasible due to their small size (0.6 × 0.6 × 2.4 mm³). Therefore, scaled-up rectangular cochlear implants (5 × 5 × 20 mm³, 10 × 10 × 40 mm³, and 20 × 20 × 80 mm³) were fabricated using stereolithography and subjected to torsion testing. Finite element analysis (FEA) accurately represented the linear behavior observed in the torsion experiments. We then used the validated Finite element analysis models to study the mechanical behavior of real-sized implants fabricated from the IP-Q resin. Mechanical characterization of both implant designs, with different inner porous structures (pore size: 20 μm and 60 μm) and a hollow version, revealed that the cylindrical implants exhibited approximately three times higher stiffness and mechanical strength as compared to the rectangular ones. The influence of the pore sizes on the mechanical behavior of these implant designs was found to be small. Based on these findings, the cylindrical design, regardless of the pore size, is recommended for further research and development efforts.

Bioprocess optimization towards higher productivity and better quality control relies on real-time process monitoring tools to measure process and culture parameters. Cell concentration and viability are among the most important parameters to be monitored during bioreactor operations that are typically determined using optical methods on an extracted sample. In this paper, we have developed an online non-invasive sensor to measure cell concentration and viability based on Doppler ultrasound. An ultrasound transducer is mounted outside the bioreactor vessel and emits a high frequency tone burst (15 MHz) through the vessel wall. Acoustic backscatter from cells in the bioreactor depends on cell concentration and viability. The backscattered signal is collected through the same transducer and analyzed using multivariate data analysis (MVDA) to characterize and predict the cell culture properties. We have developed accurate MVDA models to predict the Chinese hamster ovary (CHO) cell concentration in a broad range from 0.1 × 106 cells/mL to 100 × 106 cells/mL, and cell viability from 3% to 99%. The non-invasive monitoring is ideal for single use bioreactor and the in-situ measurements removes the burden for offline sampling and dilution steps. This method can be similarly applied to other suspension cell culture modalities.

This work investigates the effect of pre-test curing at various durations on the stress-settlement of gypseous sand soil treated with varying percentages of nanoclay. The tests are performed on a soil sample from Al-Jameh district in northern Al-Najaf city, Iraq. The soil sample is disturbed and remolded in the Oedometer cell. The remolded specimen will be at 90% of the maximum dry density from the standard Proctor test. Four data sets related to the percentages of adding nanoclay, 0, 3, 6 and 12 %. Each data set includes three groups of pre-test curing periods (Tc), 0, 1 and 4 days. For each tested specimen, a gradual incremental normal stress is applied, i.e., 50, 100 and 200 kPa. For the soil without nanoclay, it was an interesting result for the performance under all vertical stresses that there is a slight decrease in the final settlement. This situation may be attributed to the re-bonded of the particles by the gypsum during the curing time. There was a clear decrease in the final settlement for the nanoclay-treated soil specimens compared to the natural state of the soil (without nanoclay). While a significant decrease in settlement is recorded for specimens with nanoclay (NC) of 6%, which is the best percentage of nanoclay.

The high kaolinite content of metakaolin makes it valuable to other industries, thereby affecting its availability and affordability for the production of limestone calcined clay cement (LC3). This work presents a study on the potential utilization of low-grade clay in place of pure metakaolin in the preparation of LC3 for mortar formulations. CEM I was partially substituted with calcined clay and limestone by 20, 30, 40, and 50 wt.%. The weight ratio of calcined clay and limestone was maintained at 2:1 for all mixes and the water-to-binder ratio was 0.48. X-ray diffraction (XRD), thermogravimetric analysis (TGA), and isothermal conduction calorimetry were used to study the hydration process and products after 28 days. Mechanical and durability assessments of the LC3 mortar specimens were conducted. LC3 specimens (marked LC20%, LC30%, LC40%, and LC50%) trailed the control sample by 1.2%, 4%, 9.8%, and 18%, respectively, at 28 days and 1.6%, 2.3%, 3.6%, and 5.5%, respectively, at 91 days. The optimum replacement of OPC clinker, calcined clay, and limestone was 20% (LC20%).

The term “تضخیم الأنا” in Arabic is closely related to the concept of narcissism and a sense of self-importance; because putting too much importance in one’s self will lead to narcissism in its highest stages. This article attempts to investigate and analyze this issue as well as decentralism and cultural antagonism on the one hand and centralism and nationalism on the other, which is discussed by writers and critics in Arabic literature as a contradictory action. This article will therefore investigate the challenge this issue is causing. This article will show that the actions of some Arab critics and writers have led to the loss of the spirit of moderation and cultural connection, resulting in othering and the emergence of hegemonic discourse. In such works, the discourse is based on a central signifier, which is narcissism. Therefore, an attempt has been made to show the methods of othering and sense of self-importance by Arab writers and critics. In this study, an attempt has been made to prove, according to the critical discourse analysis approach of Ernesto Laclau and Chantal Mouffe, that othering and marginalizing the other will eventually become a chronic disease, which will result in a crisis-afflicted and perplexed generation which is stuck between their past and present.

We conducted a systematic review of the published literature relating to the assessment and measurement of wellness in order to answer the following questions: 1) What is the working definition of wellness? 2) What wellness assessment instruments have been evaluated or applied in medical settings? 3) How valid, reliable, and accessible are these wellness assessment tools? The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for this systematic review. Studies published from1990 to 2016 on wellness assessment were identified through Medline and PsycINFO using the following keywords: assessment OR evaluation OR measurement AND wellness OR wellbeing. Two authors independently conducted a focused analysis then reached a consensus on 23 studies that met the specific selection criteria. This review revealed that there is a lack of uniform definition of wellness. The studies utilizing wellness assessment tools demonstrate strongest reliability values for the following instruments: Wellness Evaluation of Lifestyle, Five-factor Wellness Evaluation of Lifestyle, Perceived Wellness Survey, the Optimal Living Profile, and the Body-Mind-Spirit Wellness Behavior and Characteristic Inventory. However, there is insufficient evidence to support the clinical utility of a single particular wellness instrument. Properly defining wellness might help drive the development and validation of more precise assessment and measurement methods. This could reinforce interventions that promote wellness.

Black Ti (bTi) surfaces comprising high aspect ratio nanopillars exhibit a rare combination of bactericidal and osteogenic properties, framing them as cell-instructive meta-biomaterials. Despite the existing data indicating that bTi surfaces induce osteogenic differentiation in cells, the mechanisms by which this response is regulated are not fully understood. Here, we hypothesized that high aspect ratio bTi nanopillars regulate cell adhesion, contractility, and nuclear translocation of transcriptional factors, thereby inducing an osteogenic response in the cells. Upon the observation of significant changes in the morphological characteristics, nuclear localization of Yes-associated protein (YAP), and Runt-related transcription factor 2 (Runx2) expression in the human bone marrow-derived mesenchymal stem cells (hMSCs), we inhibited focal adhesion kinase (FAK), Rho-associated protein kinase (ROCK), and YAP in separate experiments to elucidate their effects on the subsequent expression of Runx2. Our findings indicated that the increased expression of Runx2 in the cells residing on the bTi nanopillars compared to the flat Ti is highly dependent on the activity of FAK and ROCK. A mechanotransduction pathway is then postulated in which the FAK-dependent adhesion of cells to the extreme topography of the surface is in close relation with ROCK to increase the endogenous forces within the cells, eventually determining the cell shape and area. The nuclear translocation of YAP may also enhance in response to the changes in cell shape and area, resulting in the translation of mechanical stimuli to biochemical factors such as Runx2.

BACKGROUND: Similar rates of remission from Major Depressive Disorder (MDD) have been documented between ethnic groups in response to antidepressant treatment. However, ethnic differences in functional outcomes, including patient-reported quality of life (QOL) and functioning, have not been well-characterized. We compared symptomatic and functional outcomes of antidepressant treatment in Hispanic and non-Hispanic patients with MDD. METHODS: We analyzed 2280 nonpsychotic treatment-seeking adults with MDD who received citalopram monotherapy in Level 1 of the Sequenced Treatment Alternatives to Relieve Depression study. All subjects (239 Hispanic, 2041 non-Hispanic) completed QOL, functioning, and depressive symptom severity measures at entry and exit. RESULTS: Hispanic participants had significantly worse QOL scores at entry and exit (p < 0.01). However, after controlling for baseline QOL, there was no difference between Hispanic and non-Hispanic patients QOL at exit (p = 0.21). There were no significant between-group differences at entry or at exit for depressive symptom severity or functioning. Both groups had significant improvements in depressive symptom severity, QOL, and functioning from entry to exit (all p values < 0.01). Patients with private insurance had lower depressive symptom severity, greater QOL, and better functioning at exit compared to patients without private insurance. LIMITATIONS: This study was a retrospective data analysis, and the Hispanic group was relatively small compared to the non-Hispanic group. CONCLUSIONS: Hispanic and non-Hispanic participants with MDD had similar responses to antidepressant treatment as measured by depressive symptom severity scores, quality of life, and functioning. Nevertheless, Hispanic patients reported significantly worse quality of life at entry.

The maritime sector is striving to lessen its dependence on fossil fuels, motivated by both economic factors related to fuel efficiency and the policies established by the International Maritime Organization (IMO). Consequently, there has been a growing focus on developing and deploying all-electric ships (AES) as a more sustainable alternative to conventional fossil fuel-powered vessels. AES presents several advantages over conventional ships, including zero emissions, enhanced energy efficiency, and greater sustainability. However, the implementation of AES also brings new challenges, such as the necessity to manage a hybrid microgrid and optimize voyage scheduling. Hybrid fuel cell (FC)-battery energy storage (BES) technology can significantly contribute to addressing these requirements. To tackle these challenges, this article introduces a comprehensive framework for the optimal planning of hybrid microgrids and voyage scheduling in AES. The framework incorporates multi-objective optimization techniques based on genetic algorithms to achieve a balance between cost and voyage time. The proposed framework is applied to a case study of a ship operating on a fixed route between two ports. The simulation results indicated that the total cost per voyage, associated with the objective function of cost minimization and voyage time reduction, has decreased by 12% and increased by 40%, respectively, when compared to the regular ship speed profile. Additionally, the travel time has been reduced by half an hour and 2 h, respectively, in comparison to the regular ship speed profile. To verify the results, the optimization problem for cost and voyage scheduling is also solved by Mayfly Algorithm (MA) separately. Thus, it can be illustrated the effectiveness of the framework in enhancing energy efficiency and fuel economy while preserving the ship's performance. • Fuel cell-powered ship's energy management and voyage scheduling co-optimization. • All-electric ship (AES) optimal planning for economic and sustainable operation. • Considering ship speed profile management in optimal AES voyage scheduling. • Incorporating the dimensional constraints into the AES optimal design strategy. • Considering generation reserve capacity to supply unanticipated shipboard demands. [ABSTRACT FROM AUTHOR]

We investigated the physico-mechanical properties of mortar mixed with copolymers based on polyvinyl alcohol (PVA) and 2-ethylhexyl acrylate (2-EHA) and synthesized by grafting using ammonium persulfate (APS) as an initiator. Increasing the amount of 2-EHA in the copolymer from 4% to 8% reduced the water/cement (W/C) ratio, the initial and final setting times, and the water absorption of mortar, while it increased its compressive strength.