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The purpose of this study was to investigate whether the layout has an effect on cross-contaminations levels at farmers markets.

We used social cognitive theory's triadic reciprocity model to investigate how influencing the environment could change the behaviors of farmers’ market consumers and reduce the risk of microbial cross-contamination using a Fluorescent Compound (FC). For this purpose, a 3 × 2 experimental between-subject factorial design was utilized in this study: three farmers market layouts (i.e. U-shaped [U-S], L-shaped [L-S] and square-shaped [S–S]) and two different set-ups per market (i.e. produce and non-produce vendors completely separated, and alternating produce and non-produce vendors). FC was utilized to simulate microbial contamination on the participants (n = 54) hands. The participants were allowed to walk through the layout for 3 min and touch items after which a total of 475 swab samples were processed and recorded for absorbance levels.

The results indicated that the cross-contamination level of the U-S market was significantly lower (p < 0.001) than those of the L-S and S–S markets. The best market layout and set-up based on the average levels of simulated cross-contamination were the U-S market, particularly with the A set-up, where produce and non-produce booths were scattered.

This study is the first to use the quantification of FC to identify the impact of a farmers’ market layout/design on cross-contamination levels. These results can be used to provide guidance to market managers on layout and design from a safety standpoint to reduce the risk of cross-contamination.

The purpose of this study was to the synthesis of Fe₃O₄@SiO₂ nanocomposites and using it as an adsorbent for removal of diazinon from aqueous solutions. Structural characteristics of the synthesized magnetic nanocomposite were described by Fourier transform infrared spectroscopy and scanning electron microscopy.

The effects of different parameters including pH (2-10), contact time (1-180 min), adsorbent dosage (100-2000 mg L⁻¹) and initial diazinon concentration (0.5–20 mg L⁻¹) on the removal processes were studied. Finally, isotherm and kinetic and of adsorption process of diazinon onto Fe₃O₄@SiO₂ nanocomposites were investigated.

The maximum removal efficiency of diazinon (96%) was found at 180 min with 1000 mg L⁻¹ adsorbent dosage using 0.5 mg L⁻¹ diazinon concentration at pH = 7. The experimental results revealed that data were best fit with the pseudo-second-order kinetic model (R² = 0.971) and the adsorption capacity was 10.90 mg g⁻¹. The adsorption isotherm was accordant to Langmuir isotherm.

In the present study, the magnetic nanocomposites were synthesized and used as an absorbent for the removal of diazinon. The developed method had advantages such as the good ability of Fe₃O₄@SiO₂ nanocomposites to remove diazinon from aqueous solution and the magnetic separation of this absorbent that make it recoverable nanocomposite. The other advantages of these nanocomposites are rapidity, simplicity and relatively low cost.

Implications of ambiguity for the dynamics of asset prices and wealth distribution are the chief concern of this study.

In a continuous-time stochastic macro setting characterized by heterogeneous agents and financial friction with perfect “skin-in-the-game” for productive agents, we derive analytically and then illustrate numerically how ambiguity aversion would impinge on the agents’ consumption share and precautionary motives, sowing the seeds for asset price misalignment and thereby calling for appropriate policy response.

The agents’ ambiguity-aversion triggers a low real risk-free rate, fewer consumption shares, higher precautionary savings and wealth redistribution, inducing misalignment in asset prices. The distortion entails welfare loss for all agents, making a case for conventional monetary and fiscal policy design and analysis. For a given degree of ambiguity aversion, the dividend and capital value taxations could mitigate the asset price misalignment though causing a welfare loss as they are distortionary in turn. However, conventional monetary policy could lessen the asset price distortion and improve the welfare of at least a subset of agents if it is fine-tuned well.

Characterizations of ambiguity-driven asset price misalignments along with redistributive implications of ambiguity and their reflections for asset price volatility, leverage, welfare and fiscal and monetary policy conduct and analysis are the key contributions of this study.

This study aims to solve optimal pricing and power bidding strategy problem for integrated combined heat and power (CHP) system by using a modified heuristic optimization algorithm.

In electricity markets, generation companies compete according to their bidding parameters; therefore, optimal pricing and bidding strategy are solved. Recently, CHP units are significantly operated by generation companies to meet power and heat, simultaneously.

For validation, it is shown that profit is improved by 0.04%–48.02% for single and 0.02%–31.30% for double-sided auctions. As heat price curve is extracted, the simulation results show that when CHP system is integrated with other units results in profit increase and emission decrease by 3.04%–3.18% and 2.23%–4.13%, respectively. Also, CHP units significantly affect bidding parameters.

The novelties are pricing and bidding strategy of integrated CHP system is solved; local heat selling is considered in pricing and bidding strategy problem and heat price curve is extracted; the effects of CHP utilization on bidding parameters are investigated; a modified heuristic and deterministic optimization algorithm is presented.

The purpose of this study is to investigate the effects of the shear-thinning viscoelastic behavior of the surrounding matrix on droplet deformation by weakly compressible smoothed particle hydrodynamics (WC-SPH). Also, the effect of the presence of another droplet is examined.

A modified consistent weakly compressible SPH method is proposed. After code verification, a complete parameter study is performed for a drop under the simple shear flow of a Giesekus liquid. The investigated parameters are 0.048≤Ca ≤ 14.4, 0.1≤c ≤ 10, 0.04≤De ≤ 10, 0≤α ≤ 1 and 0.12≤Re ≤ 12.

It is demonstrated that the rheological behavior of the surrounding fluid could dramatically affect the droplet deformation. It is shown that the droplet deformation is increased by increasing Re and Ca. In contrast, the droplet deformation is decreased by increasing a, De and polymer content. Also, it is indicated the presence of another droplet could drastically affect the flow field, and the primary stress difference (N1) is resonated between two droplets.

The main originality of this paper is to introduce a new consistent WC-SPH algorithm. The proposed method is very versatile for tackling the shear-thinning viscoelastic multiphase problems. Furthermore, a complete parameter study is performed for a drop under the simple shear flow of Giesekus liquid. Another novelty of the current paper is studying the effect of the presence of a second droplet. To the best of the authors’ knowledge, this is performed for the first time.

Previous research indicates that vitamin D and omega-3 co-supplementation may benefit overall health, but current evidence regarding its effects on lipid profile remains unclear. The present systematic review and meta-analysis aimed to examine the effects of vitamin D and omega-3 co-supplementation on lipid profile (total cholesterol [TC], low-density lipoprotein [LDL], triglyceride [TG] and high-density lipoprotein [HDL]) in adults.

In this systematic review and meta-analysis, relevant studies were obtained by searching the PubMed, Scopus and Web of Science databases (from inception to January 2022). Weighted mean differences and 95% confidence intervals were estimated via a random-effects model. Heterogeneity, sensitivity analysis and publication bias were reported using standard methods.

Pooled analysis of six randomized controlled trials (RCTs) revealed that vitamin D and omega-3 co-supplementation yielded significant reductions in TG (p = 0.631). A pooled analysis of five trials indicated a significant association between omega-3 and vitamin D treatment and reductions in TC (p = 0.001) and LDL (p = 0.001). Although, pooled analyses of omega-3 and vitamin D did not significantly affect HDL.

The findings suggest that vitamin D and omega-3 co-supplementation lowers TG, TC and LDL in adults. Future, large-scale, RCTs on various populations are needed to elucidate further beneficial effects of vitamin D and omega-3 co-supplementation on lipid profile and establish guidelines for clinical practice.

This paper aims to study numerically the non-Newtonian solution of carboxymethyl cellulose in water along with copper oxide nanoparticles, which flow turbulently through twisted smooth and finned tubes.

The twisted-tape inserts of rectangular and triangular sections are investigated under constant wall heat flux and the nanoparticle concentration varies between 0% and 1.5%. Computational fluid dynamics simulation is first validated by experimental information from two test cases, showing that the numerical results are in good agreement with previous studies. Here, the impact of nanoparticle concentration, tube twist and fins shape on the heat transfer and pressure loss of the system is measured. It is accomplished using longitudinal rectangular and triangular fins in a wide range of prominent parameters.

The results show that first, both the Nusselt number and friction factor increase with the rise in the concentration of nanoparticles and twist of the tube. Second, the trend is repeated by adding fins, but it is more intense in the triangular cases. The tube twist increases the Nusselt number up to 9%, 20% and 46% corresponding to smooth tube, rectangular and triangular fins, respectively. The most twisted tube with triangular fins and the highest value of concentration acquires the largest performance evaluation criterion at 1.3, 30% more efficient than the plain tube with 0% nanoparticle concentration.

This study explores an innovative approach to enhancing heat transfer in a non-Newtonian nanofluid flowing through an oval tube. The use of twisted-tape inserts with rectangular and triangular sections in this specific configuration represents a novel method to improve fluid flow characteristics and heat transfer efficiency. This study stands out for its originality in combining non-Newtonian fluid dynamics, nanofluid properties and geometric considerations to optimize heat transfer performance. The results of this work can be dramatically considered in advanced heat exchange applications.

Health-care workers (HCWs) are at increased risk of exposure to the COVID-19 virus, which necessitates implementing transmission prevention measures in health-care delivery facilities, particularly hospitals. This study aims to assess COVID-19 risk in a health-care setting and recommend managerial strategies to cope with existing risk procedures.

This cross-sectional study was conducted among HCWs working in a general hospital in Qazvin, northwest of the country. A total of 310 employees working at different clinical and non-clinical occupational levels participated in the study. The WHO COVID-19 risk assessment tool categorised HCWs in high- or low-risk groups exposed to COVID-19 infection.

Findings revealed statistically significant relationships between workplace exposure to the COVID-19 virus and variables, including job type, performing the aerosol-generating procedure, access to personal protective equipment (PPE) and being trained on Infection Prevention and Control (IPC) guidelines (p < 0.05). HCWs older than 36 years were at 8% more risk of COVID-19 virus. Being a medical doctor or delivering health-care services as a nurse were relatively 28% and 32% times more likely to be at high risk of infection than other hospital staff categories. Having inadequate access to PPE and lack of training on IPC guidelines were also key determinants of high-risk infection.

As most cases at risk of COVID-19 infection belonged to frontline health-care staff in older age groups, this study recommend limiting the exposure of vulnerable staff to COVID-19 patients, increasing protective measures for HCWs and providing essential information about infection control procedures.

The purpose of this study to investigate acetaminophen (ACT) degradation efficiencies by using ozone/persulfate oxidation process in a batch reactor. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated.

The experiments were in the 2 L glass vessels. Ozone gas with flow rate at 70 L.h⁻¹ was produced by ozone generator. After the adjustment of the pH, various dosages of persulfate (1, 3, 5, 7 and 9 mmol.L⁻¹) were then added to the 500 mL ACT-containing solution with 150 mg.L⁻¹ of concentration. Afterward, ozone gas was diffused in glass vessels. The solution after reaction flowed into the storage tank for the detection. The investigated parameters included pH and the amount of ozone and persulfate addition. For comparison of the ACT degradation efficiency, ozone/persulfate, ozone and persulfate oxidation in reactor was carried out. The ACT concentration using a HPLC system equipped with 2998 PDA detector was determined at an absorbance of 242 nm.

ACT degradation percentage by using ozone or persulfate in the process were at 63.7% and 22.3%, respectively, whereas O₃/persulfate oxidation process achieved degradation percentage at 91.4% in 30 min. Degradation efficiency of ACT was affected by different parameter like pH and addition of ozone or persulfate, and highest degradation obtained when pH and concentrations of persulfate and ozone was 10 and 3 mmol.L⁻¹ and 60 mg.L⁻¹, respectively. O₃, OH^• and SO⁴⁻ were evidenced to be the radicals for degradation of ACT through direct and indirect oxidation. Gas chromatography–mass spectrometer analysis showed intermediates including N-(3,4-dihydroxyphenyl) formamide, hydroquinone, benzoic acid, 4-methylbenzene-1,2-diol, 4-aminophenol.

This study provided a simple and effective way for degradation of activated ACT as emerging contaminants from aqueous solution. This way was conducted to protect environment from one of the most important and abundant pharmaceutical and personal care product in aquatic environments.

There are two main innovations. One is that the novel process is performed successfully for pharmaceutical degradation. The other is that the optimized conditions are obtained. In addition, the effects of various parameters on the ACT removal efficiency toward pathway inference of ACT degradation were investigated.

Appropriate access to formally-trained health workers for people living in rural and underdeveloped areas is a continuing challenge worldwide. The purpose of this paper is to investigate the willingness of formally-trained health workers to practice in underdeveloped areas and its main determinants among medical students in the western provinces of Iran.

A total of 753 medical students from four provinces in western Iran (Kermanshah, Ilam, Lorestan and Kurdistan) were surveyed cross-sectionally in 2017. A self-administrated questionnaire was used to collect data on sociodemographic characteristics, willingness to practice in underdeveloped areas, intrinsic (e.g. desire to help others and self-interest in medicine) and extrinsic (e.g. the high income of physicians and social prestige) motivations of the study population. Multivariable logistic regression was used to identify the main determinants of willingness to practice in underdeveloped areas among medical students after their graduation.

The results indicated that 58.3 percent of students were willing to practice in underdeveloped areas. While 59 percent of the study population had a strong extrinsic motivation to study medicine, the remaining 41 percent of the study population had a strong intrinsic motivation to study medicine. The logistic regression results indicated that low parental professional and educational status, an experience of living in rural areas and having strong intrinsic motivation were associated with greater willingness to practice in underdeveloped areas.

This is the first study to investigate the willingness to practice in underdeveloped areas and its main determinants among medical students in the west of Iran.