Job stress and job satisfaction are important factors affecting workforce productivity. This study was carried out to investigate the job stress, job satisfaction, and workforce productivity levels, ...to examine the effects of job stress and job satisfaction on workforce productivity, and to identify factors associated with productivity decrement among employees of an Iranian petrochemical industry.
In this study, 125 randomly selected employees of an Iranian petrochemical company participated. The data were collected using the demographic questionnaire, Osipow occupational stress questionnaire to investigate the level of job stress, Job Descriptive Index to examine job satisfaction, and Hersey and Goldsmith questionnaire to investigate productivity in the study population.
The levels of employees' perceived job stress and job satisfaction were moderate-high and moderate, respectively. Also, their productivity was evaluated as moderate. Although the relationship between job stress and productivity indices was not statistically significant, the positive correlation between job satisfaction and productivity indices was statistically significant. The regression modeling demonstrated that productivity was significantly associated with shift schedule, the second and the third dimensions of job stress (role insufficiency and role ambiguity), and the second dimension of job satisfaction (supervision).
Corrective measures are necessary to improve the shift work system. “Role insufficiency” and “role ambiguity” should be improved and supervisor support must be increased to reduce job stress and increase job satisfaction and productivity.
In this study, natural convection in solar air heaters with different fins is numerically investigated. Effect of fin shape (rectangular, elliptical and triangular), the inclination angle (45–90°) on ...mass flow rate, temperature and performance are studied by considering the effect of shadow created by fins. Three different cases, solar air heater with fins considering shadow effect (Shadow Effect Considered: SEC), ones with fins neglecting shadow effect (Shadow Effect Neglected: SEN), and ones without fins (WF) are compared. It can be concluded that shadow created by fins, which eliminates some part of absorber from playing a direct role in heat transfer, has a significant impact on finding the best performance and dimensions of fins. For example, the performance of rectangular and triangular fins in case SEC are about 10% and 20% less than case SEN. Due to fins shadow, mass flow rates in solar air heaters without fins (WF) is more than solar air heaters with fins in higher inclination angles. While the highest mass flow rate is achieved for depth between 0.005 and 0.010 m, but the best depth from performance point of view is about 0.025 m and improvement in performance is negligible for larger depths.
•Effect of fins' shadow on solar air heaters are numerically studied.•For β > 80°, using Triangular and elliptical fins is not beneficial.•The highest mass flow rate is obtained by rectangular fins.•For β > 60°, using fins lead lower mass flow rates.•Considering the performance of solar heater, a fin depth of 25 mm is recommended.
Fluoride concentration, if exceeds the standard levels in drinking water, can lead to adverse effects on human health. Adsorption is one of the widely considered appropriate technologies for water ...defluoridation. In this study, modified pumice with HCl and NaOH were used for the fluoride removal from aqueous solution, and two linear forms of the Langmuir and Freundlich isotherms model were applied to determine the best fit of equilibrium expressions. Several experimental parameters including pH (2-10), temperature (20-60°C), adsorbent dosage (2-10 g/L), fluoride concentration (5-20 mg/L), and contact time were studied. Results showed that removal efficiency improved with increase in contact time, initial fluoride concentration, and adsorbent dosage. The maximum removal efficiency (96%) was observed at pH 6, 10 g/L adsorbent dosage, 20°C solution temperature, 90-min reaction time, and 20 mg/L of fluoride concentration. The kinetic studies indicated that the adsorption equilibrium and kinetic data were in good agreement with the Langmuir Model (R
2
= 0.95) with q
max
= 65.5 mg/g and pseudo-second-order reaction (R
2
= 0.99). According to the results, the modified pumice was found to be able to remove fluoride from aqueous environments with good removal efficiency and adsorption capacity.
One of the most important causative agents of visceral leishmaniasis (VL) is
, which is mainly spread by
and
sandflies in the Old and New World, respectively. Novel and effective drugs to manage this ...neglected vector-borne disease are urgently required. In this study, we evaluated the toxicity of carvacrol, thymol and linalool, three common essential oil constituents, on amastigotes and promastigotes of
.
: in vitro experiments were performed by 24 h MTT assay. Carvacrol, thymol and linalool at concentrations ranging from 1.3 to 10 μg/mL were tested on promastigotes of
. For in vivo test, two groups of hamsters (
) received 100 mg/kg of body weight/day of carvacrol and thymol as intraperitoneal injection on day 7 post-infection, followed by a 48 h later injection. The third group was treated with the glucantime as standard drug (500 mg/kg) and the last group (control) just received normal saline. On the 16th day, the number of parasites and histopathological changes in liver and spleen were investigated.
24 h MTT assay showed promising antileishmanial activity of thymol and carvacrol, with IC
values of 7.2 (48 μM) and 9.8 μg/mL (65 μM), respectively. Linalool at all concentrations did not affect
promastigote viability. In vivo toxicity data of carvacrol and thymol showed that the former at 100 mg/kg was the safest and most effective treatment with little side effects on the liver.
Overall, thymol and carvacrol are highly promising candidates for the development of effective and safe drugs in the fight against VL.
The Zagros forest ecosystem is being threatened by increasing number of forest fires. These forests are generally in coppice form and oak sprout clumps occupy forest area like patches. We examined ...some microbial and physical–chemical properties of burned soil to understand the response of soil microbial activity to different fire severities one year after burning. Soil collected from areas subjected to different fire severities was visually classified as: unburned-inside of sprout clumps (UI), unburned-outside of sprout clumps (UO), burned with low severity-outside of sprout clumps (BLO), burned with moderate severity-inside of sprout clumps (BMI), and burned with high severity-inside of sprout clumps (BHI). Increases in soil pH and available P and decreases in soil N and C/N ratio occurred only at BHI. SOC decreased in BHI and BMI compared to UI but no change was observed in BLO compared to UO. The areas subjected to high severity burn contained the most bacterial and the least fungal colony forming units (CFUs). Basal respiration decreased in BMI and BHI while substrate-induced respiration (SIR), and alkaline and acid phosphatase activities were only decreased in BHI compared UI. Discriminate analysis showed that the linear combination of acid and alkaline phosphatase activity, fungal CFUs, and SIR were respectively the most effective variables to differentiate the treatments. We concluded that acid and alkaline phosphatase activities can efficiently represent the degree of fire impact on soil even one year after fire.
•Neither microbial nor physical–chemical factors are changed by low fire severity.•Some physical–chemical and all microbial factors are changed by high fire severity.•Acid and alkaline phosphatase activities are decreased only by high fire severity.•Bacteria are increased and fungi decreased profoundly by the high fire severity.•Phosphatase activities can best discriminate the different burning severities.
Background. Fluorouracil (5-FU) is the third most common chemotherapeutic agent used in the treatment of solid tumors. 5-FU-associated cardiotoxicity ranks the second causes of cardiotoxicity induced ...by chemotherapeutic drugs after anthracyclines. Kaempferol (KPF), a common flavonoid, possessing anti-inflammatory, antiapoptotic, antioxidative properties, and its protective effects on cardiovascular disease has been reported in various studies. The current study is aimed at appraising the effect of KPF and KPF nanoparticles (NPs) on 5-FU-induced cardiotoxicity in rats. Methods. Thirty Male Wistar rats were divided into five groups as follows: control, 5-FU, 5-FU+10 mg/kg vitamin C, 5-FU+ 1 mg/kg KPF, and 5-FU+ 1 mg/kg KPF-NPs. Cardiotoxicity was induced with an intraperitoneal injection of a single dose of 5-FU (100 mg/kg). The control group received normal saline, and the treatment groups received KPF and KPF-NPs with an intraperitoneal injection for 14 days. Each heart histopathological lesions were given a score of 0 to 3 in compliance with the articles for statistical analysis. Results. 5-FU resulted in a significant cardiotoxicity represented by an increase in cardiac enzymes, MDA (malondialdehyde) levels, COX-2 (cyclooxygenase-2) expression, and histopathological degenerations. 5-FU treatment also decreased body weight, TAC (total antioxidant capacity) values, VEGF (vascular endothelial growth factor) expression, blood cells, and hemoglobin (Hb) levels. Treatment with KPF and KPF-NPs reduced oxidative stress, cardiac enzymes, COX-2 expression, and VEGF expression. The number of blood cells, Hb levels, and histopathological degenerations, in cardiac tissue also body weight of animals, increased, followed by treatment with KPF and KPF-NPs. Conclusion. Our results demonstrated that treatment with KPF and KPF-NPs significantly improved cardiotoxicity induced by 5-FU in rats.
αB-Crystallin (αB-Cry) is expressed in many tissues, and mutations in this protein are linked to various diseases, including cataracts, Alzheimer's disease, Parkinson's disease, and several types of ...myopathies and cardiomyopathies. The p.D109G mutation, which substitutes a conserved aspartate residue involved in the interchain salt bridges, with glycine leads to the development of both restrictive cardiomyopathy (RCM) and skeletal myopathy. In this study, we generated this mutation in the α-Cry domain (ACD) which is crucial for forming the active chaperone dimeric state, using site-directed mutagenesis. After inducing expression in the bacterial host, we purified the mutant and wild-type recombinant proteins using anion exchange chromatography. Various spectroscopic evaluations revealed significant changes in the secondary, tertiary, and quaternary structures of human αB-Cry caused by this mutation. Furthermore, this pathogenic mutation led to the formation of protein oligomers with larger sizes than those of the wild-type protein counterpart. The mutant protein also exhibited increased chaperone activity and decreased chemical, thermal, and proteolytic stability. Atomic force microscopy (AFM), transmission electron microscopy (TEM), and fluorescence microscopy (FM) demonstrated that p.D109G mutant protein is more prone to forming amyloid aggregates. The misfolding associated with the p.D109G mutation may result in abnormal interactions of human αB-Cry with its natural partners (e.g., desmin), leading to the formation of protein aggregates. These aggregates can interfere with normal cellular processes and may contribute to muscle cell dysfunction and damage, resulting in the pathogenic involvement of the p.D109G mutant protein in restrictive cardiomyopathy and skeletal myopathy.
Sexual violence increases the risk of adverse health outcomes among female sex workers (FSWs). Using data from the 2015 national bio-behavioral survey, we explored the experience of sexual violence ...and its associated factors among Iranian FSWs. Lifetime and recent sexual violence were reported by 40.1% and 16.9%, respectively. History of substance use, ever engaging in anal sex, engaging in group sex within the last year, a high number of clients, recent unstable housing, and incarceration increased the likelihood of experiencing recent sexual violence. These findings underscore the need for community-empowerment and policy-level interventions to address violence among FSWs in Iran.
•Sonication decreased the apparent viscosity of the κ-carrageenan solution.•Sonication reduced the affinity constant between κ-carrageenan and β-lactoglobulin.•Sonication downsized nanoparticles ...formed in the mixed dispersion with protein.•Complexation in mixed BLG–KC dispersions is a nucleation and growth mechanism.
The influence of κ-carrageenan (KC) depolymerization using ultrasound on its interaction with β-lactoglobulin (BLG) was investigated by isothermal titration calorimetry (ITC), turbidity measurement, dynamic light scattering and zeta-potential analyses. Time and amplitude of the sonication had a direct effect on the viscosity depression, while the sonication temperature had an opposite effect. ITC measurements indicated that the sonication significantly decreased the affinity constant between KC and BLG. The zeta-potential of the nanoparticles produced from ultrasonicated (US) KC–BLG associative interaction was lower than of those produced from intact (IN) KC–BLG interaction. These differences were attributed to the lower charge density of the KC (US) as a result of sonochemical interactions. Polydispersity and particle size measurements showed that the effect of the sonication was the homogenisation of the nanoparticles in the mixed dispersion. The nanoparticles formed may therefore be useful as a delivery system for fortification purposes of acidic beverages.
As a platinum-containing anticancer drug, cisplatin is the keystone for treating many malignancies. Nephrotoxicity is the main dose-limiting toxicity, and several hydration therapies and ...supplementary strategies are utilized to reduce cisplatin-induced kidney damage, so the discovery and development of effective and safe antitumor drugs are still on the path of human health. Herein, a new four-coordinated Pt complex Pt(TSC)Cl using N(4)-phenyl-2-formylpyridine thiosemicarbazone (HTSC) was synthesized and characterized by single-crystal X-ray diffraction,
HNMR, FT-IR, LC/MS and CHN elemental analysis. The Pt(TSC)Cl complex revealed antiproliferative activity against A549, MCF-7 and Caco-2 cell lines with a low micromolar IC
(200-1.75 µM). Specifically, the Pt(TSC)Cl complex displayed more selectivity in Caco-2 cells (IC
= 2.3 µM) than cisplatin (IC
= 107 µM) after 48 h of treatment. Moreover, compared with cisplatin, a known nephrotoxic drug, the Pt(TSC)Cl complex exhibited lower nephrotoxicity against Hek293 normal cells. We also found that the Pt(TSC)Cl complex can effectively prevent cancer cell propagation in sub-G1 and S phases and induce apoptosis (more than 90%). Real time PCR and western analysis demonstrated that the expression pattern of apoptotic genes and proteins is according to the intrinsic apoptosis pathway through the Bax/Bcl-2-Casp9-Casp3/Casp7 axis. Collectively, our findings indicated that the Pt(TSC)Cl complex triggers apoptosis in Caco-2 cell lines, while low nephrotoxicity was shown and may be considered a useful anticancer drug candidate for colorectal cancers for further optimization and growth.
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