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Objective: The current study was designed to investigate the protective effects of curcuma caplet against titanium dioxide nanoparticles (nTiO2)-induced damage in liver and kidney of male Wistar rats. Materials and Methods: Thirty adult (7-8 week old) male rats (200 g) were randomly divided into 5 groups of 6 each. The first and second groups received olive oil and nTiO2 (300 mg/kg body weight) as control and nTiO2 groups, respectively. The third, fourth, and fifth groups received Curcuma at concentrations of 100, 200, and 300 mg/kg body weight in addition to 300 mg/kg body weight of nTiO2, respectively. The treatment was performed through gavage for 3 weeks. Rats' blood was examined for total antioxidant capacity (TAC), total oxidant status (TOS), and malondialdehyde (MDA) levels as well as antioxidant enzymes superoxide dismutase (SOD), and glutathione peroxidase (GPx), and activity of liver enzymes alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and renal factors (urea, uric acid, and creatinine). Histological analyses were also performed to estimate the extent of hepatic and renal injury. Results: nTiO2-induced liver and kidney damage by decreased serum SOD, GPx, and TAC (p<0.05). Fu +rthermore, nTiO2 increased serum MDA and TOS, and renal (Creatinine, Urea and Uric acid) and liver parameters (ALT, AST, ALP and LDH) (p<0.05). However, Curcuma treatment was able to moderate these changes dramatically (p<0.05). The results were confirmed by histopathological data. Conclusion: This study showed the antioxidant properties of curcuma against the side effects of nTiO2. Keywords: Curcuma, Titanium dioxide nanoparticles, Toxicity, Wistar rats [ABSTRACT FROM AUTHOR]

Silica coating on a gold nanoparticle can improve its thermal application in cancer thermotherapy. In this paper, the interfacial thermal conductance between gold and silica is calculated utilizing classical non-equilibrium molecular dynamics. It is revealed that the results of molecular dynamics are different from what has been predicted by the conventional diffuse mismatch model. Furthermore, the interfacial thermal conductance between amorphous SiO2 and gold is approximately twice that of crystalline silica, which is explained by calculating the vibrational density of state mismatches. The interfacial thermal conductance variations in terms of van der Waals interaction strength between gold and silica are also investigated. It is revealed that the conductance increases by about 30% by increasing the simulation temperature from 300 to 700 K. The results of this paper can be useful in nanofluid systems, in addition to the application of silica-coated gold nanoparticles in cancer thermal therapy. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is considered one of the leading health issues that are egregiously threatening human life throughout the world. Several epidemiological studies have examined the relationship of a particular matter < 10 μm (PM10) exposure and with type 2 diabetes mellitus (T2DM) prevalence and incidence. Accordingly, the current study is a study investigating the independent influence of air pollution (AP) and rs10830963 on the incidence of T2DM. A total number of 2428 adults over 20 years of age participated in a prospective cohort (TCGS) during a 9-year follow-up phase. The concentration of AP was measured, and the obtained values were considered the mean level in three previous years since the exposure concentration took the people living in that location. The COX regression model was employed to determine the influence of AP and rs10830963 on the incidence of T2DM in adjustment with covariate factors. Among the 392 T2DM, 230 cases (58.7%) were female diabetics, and 162 (41.3%) were male diabetics. According to the multivariable-adjusted model, exposure to PM10 (per 10 μm/m3), associated with the risk of T2DM, although just a borderline (p = 0.07) was found in the multivariable model (HR; 1.50, 95% CI; 1-2.32). The rs10830963 was directly associated with the incidence of diabetes, and the GG genotype increased the T2DM rate by 113% (more than two times) (HR; 2.134, 95% CI; 1.42-3.21, p ≤ 0.001) and GC increased it by 65% (HR; 1.65, 95% CI; 1.24-2.21, p ≤ 0.001). Long-term exposure to PM10 was associated with an increased risk of diabetes. Thus, it is suggested that the individuals with variant rs10830963 genotypes fall within a group susceptible to an increased risk of T2DM arising from AP. [ABSTRACT FROM AUTHOR]

Abstract Heat transfer at the liquid-solid interface, especially when the particles are at nanoscale, can dominate the thermal properties of nanofluids. In this study we investigate the liquid-solid interfacial thermal resistance (Kapitza resistance) and particularly analyze the structure of the formed molecular nanolayer around the carbon-based nanoparticles. Employing non-equilibrium molecular dynamics simulation and thermal relaxation method, nanofluids systems with nanoparticles with different diameters and surface wettabilities were investigated. Simulation results reveal that carbon nanotubes (CNTs) with smaller diameters more effectively attract base fluid and thus show lower reduced Kapitza resistances. It was found that the thickness of the nanolayer around the nanoparticle is independent of the carbon/water interaction strength. As expected, it was shown that the value of Kapitza resistance decreases when the interaction strength increases. Based on our acquired results, a correlation was proposed for the interfacial thermal resistance of CNT/water and graphene/water with respect to the intensity of wettability of nanoparticles surface. The insight provided by our atomistic simulations can provide a better understanding of heat transfer in nanofluids systems wherein an accurate local description of heat transfer is crucial. Highlights • CNTs with lower diameter have less interfacial thermal resistance (ITR). • The strength between water and carbon has no effect on the thickness of nanolayer. • The ITR for CNT/water is less than that of graphene/water. • A correlation proposed for the ITR in terms of wettability of the nanoparticle. [ABSTRACT FROM AUTHOR]

The heat-transfer enhancement of nanofluids has made them attractive and the subject of many theoretical and experimental researches over the last decade. Of the theoretical approaches employed to investigate nanofluid properties, molecular dynamics (MD) simulation is a popular computational technique that is widely used to simulate and investigate thermophysical properties of nanofluids. In this paper, we review and discuss the MD studies conducted on the thermophysical properties of nanofluids, considering the thermal conductivity and shear viscosity as two important factors for the industrial application of nanofluids. In this study, after introducing different MD methods to calculate those parameters, we classify and review various influential effects including the volume fraction of nanoparticles, nanofluid temperature, Brownian motion of the nanoparticles, as well as the nanoparticle shape and size in terms of the thermal conductivity and viscosity of nanofluids. Viscosity has been studied to a lesser extent than the thermal conductivity of nanofluids. In our review, we note the similarities and differences between previous MD reports on nanofluids, and we highlight gaps and potential ideas that may be of interest for future studies. [ABSTRACT FROM AUTHOR]

Objective: As a first study, suicidal ideation and its correlates have been evaluated in Iranian HIV positive population. Methods: One hundred and fifty HIV-positive individuals were recruited in this cross-sectional study. The Hospital Anxiety and Depression Scale (HADS), Positive and Negative Suicide Ideation (PANSI), Pittsburgh Sleep Quality Inventory (PSQI) and Somatization subscale of Symptom Checklist 90 (SCL 90) as self- reported questionnaires were used to assess the patients' anxiety and depression status, suicidal thoughts, sleep quality and physiological factors, respectively. Results: Antiretroviral therapy and efavirenz intake did not show any significant effects on the patients' suicidal ideation. Anxiety (p<0.001), depression (p<0.001), poor physical activity (P<0.001) and sleep quality (p<0.001) were significantly associated with the patients' negative suicidal ideation. From the patients' demographic data, unemployment (p = 0.04), living alone (p = 0.01), and lack of family support (p = 0.01) were correlated with the patients' negative suicidal thoughts. Conclusion: Although hospitals are the main referral centers for providing care for HIV-positive individuals in Tehran, Iran, conducting a multi-center study with sufficient sample size from different areas of our country that include individuals with different behaviors and cultures is essential to confirm the results of this study. [ABSTRACT FROM AUTHOR]

This paper develops a numerical study of the transient response of a radiation heat shield inserted between two plane, gray, parallel, rectangular surfaces of emissivities $${\varepsilon_1 }$$ ε 1 and $${\varepsilon_2 }$$ ε 2 . All radiating surfaces have identical dimensions. The radiation shield is assumed to have different emissivities on its top $${(\varepsilon_3)}$$ ( ε 3 ) and bottom $${(\varepsilon_4 )}$$ ( ε 4 ) surfaces, and both are assumed to be different but linear functions of x coordinate. To understand the transient temperature and heat transfer characteristics of the system, a specific configuration is investigated in detail. Several graphs are provided to illustrate how these characteristics are affected by the (i) shield location, (ii) shield emissivities, (iii) the spatial dependence of shield emissivities, and (iv) emissivities of the hot and cold surfaces. This collection of graphs provides a comprehensive picture of the thermal performance of the system under transient condition. For the spatially independent emissivities of the shield, the paper also derives a closed-form analytical solution for the transient response of the shield. [ABSTRACT FROM AUTHOR]

The synthesis of a novel series of tetraarylterephthalaldehyde derivatives in an one-pot reaction is described. In this methodology 1,2,4,5-tetrachloro-3,6-diiodobenzene is treated with various aryl Grignard reagents (excess) in tetrahydrofuran to give tetraarylbenzene-1,4-diylbis(magnesium bromides). After reaction of this product with ethyl formate and aqueous quench, tetraarylterephthalaldehydes are isolated in 33-80% yields. A mechanism involving organometallic aryne intermediates is proposed. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the qualitative and Altmetrics status of 147 journals indexed in the Arts and Humanities Citation Index (AHCI). This practical-analytical study used qualitative indicators of journals and quantitative Altmetrics. Data was collected from Web of Science, Journal Citation Reports, and Altmetrics Explorer. The results showed that most of the journals this database covers are from European countries, and only one is from Asian countries. More than half of the reviewed journals have a score lower than average regarding Journal Citation Indicator, Eigenfactor Score, and Article influence score. In addition, 63 % of journals cite articles published less than 19 years ago. Nearly 20 % of journals were not on social media. There is a significant relationship between Journal Citation Indicator indices with Citing Half-life, Article influence score with Eigenfactor Score, and between qualitative and Altmetrics indicators. Most of the reviewed journals showed low-quality performance. These journals needed high scientific impact to increase their credibility and quality and remain in the Web of Science database. [ABSTRACT FROM AUTHOR]