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The vast usage of agrochemicals enhances food security globally but may pose challenge to understand the risk assessment to non-target organisms and human beings, and liver microsomes are responsible for metabolism of these agrochemicals in vivo. In this study, stereoselective metabolism of chiral triazole fungicide cyproconazole in rat liver microsomes has been investigated through chiral LC-MS/MS technique. The half-lives of four cyproconazole stereoisomers were different ranging from 95 to 187 min, and (2 S , 3 R)-cyproconazole preferentially metabolized in rat liver microsomes. In addition, the results from metabolism kinetic study indicated that rat liver microsomes showed the stronger potency to deplete (2 S , 3 R)-cyproconazole than the others. Then, homology modeling and molecular docking results revealed that the docking energy between (2 S , 3 R)−cyproconazole and the cytochrome P450 CYP3A1 (−7.46 kcal⋅mol−1) was higher than the others, meaning that (2 S , 3 R)−cyproconazole exhibited the strongest binding ability to this enzyme. Moreover, two main metabolites of cyproconazole coming from hydroxylation and dehydration were observed, and possible metabolic reactions of cyproconazole in rat liver microsomes were identified through using an LCQ ion trap mass spectrometer. This kind of systematic metabolic investigation of cyproconazole at chiral level would provide valuable information for ecological and human health risk assessment of chiral pesticides. Image 1 • Stereoselective metabolism of cyproconazole was found in rat liver microsomes. • (2 S , 3 R)-cyproconazole is preferentially metabolized in rat liver microsomes. • Docking energy supported enantiospecific binding of cyproconazole with CYP3A1. • Two main metabolites of cyproconazole were identified by LC-MS spectrometry. [ABSTRACT FROM AUTHOR]

This paper illustrates a simple yet effective spectroscopic technique for the prediction of soil organic matter (SOM) from moist soil through the synchronous 2D correlation spectroscopy (2D-COS) analysis. In the moist soil system, the strong overlap between the water absorption peaks and the SOM characteristic features in the visible-near infrared (Vis-NIR) spectral region have long been recognised as one of the main factors that causes significant errors in the prediction of the SOM content. The aim of the paper is to illustrate how the tangling effects due to the moisture and the SOM can be unveiled under 2D-COS through a sequential correlogram analysis of the two perturbation variables (i.e., the moisture and the SOM) independently. The main outcome from the 2D-COS analysis is the discovery of SOM-related bands at the 597 nm, 1646 nm and 2138 nm, together with the predominant water absorbance feature at the 1934 nm and the relatively less important ones at 1447 nm and 2210 nm. This information is then utilised to build partial least square regression (PLSR) models for the prediction of the SOM content. The experiment has shown that by discarding noisy bands adjacent to the SOM features, and the removal of the water absorption bands, the determination coefficient of prediction (Rp2) and the ratio of prediction to deviation (RPD) for the prediction of SOM from moist soil have achieved Rp2 = 0.92 and the RPD = 3.19, both of which are about 5% better than that of using all bands for building the PLSR model. The very high RPD (=3.19) obtained in this study may suggest that the 2D-COS technique is effective for the analysis of complex system like the prediction of SOM from moist soil. [ABSTRACT FROM AUTHOR]

The present work is aimed at studying the properties of α-FeOOH adsorption for removing Cr(VI) from aqueous solution. Batch adsorption experiments were carried out to measure the influences of various parameters (contact time, pH of the medium and adsorbent dosage) for Cr(VI) adsorption taking place on the α-FeOOH nanoparticles surface. Results showed that the process of Cr(VI) adsorption was strongly dependent on the pH , displaying that the adsorption efficiency of Cr(VI) reached the maximum in the pH 3 at an initial Cr(VI) load of 15 mg/L. The thermodynamic parameters such as enthalpy change (ΔH 0 ), entropy change (ΔS 0 ), Gibbs free energy (ΔG 0 ) and Isosteric heat of adsorption were also estimated. The negative value of ΔG 0 and positive value of ΔH 0 indicated a spontaneous and an endothermic thermodynamically adsorption process, respectively. The values of ΔH x demonstrated that the interaction between α-FeOOH nanoparticles and Cr(VI) was primarily physical adsorption. The adsorption process of Cr(VI) could be simulated by the pseudo-second-order kinetic equation. Intra-particle diffusion model showed that the overall adsorption rate of α-FeOOH for Cr(VI) was dominated by the film diffusion process with some degree of intra-particle diffusion. Image 1 • The as-prepared α-FeOOH nanoparticles possessed mesoporous structures and high Cr(VI) adsorption capacity. • The Cr(VI) ions adsorption onto the α-FeOOH was an integrated physico-chemical process. • The XPS analysis demonstrated that a portion of Cr(VI) was reduced to Cr(III) by the α-FeOOH at pH 3.0. [ABSTRACT FROM AUTHOR]

Humic-like substances (HULIS) constitute a significant fraction of the water-soluble organic compounds in the environment and influence many properties of atmospheric aerosols. In this study, three solid phase extraction (SPE) methods that involve the use of hydrophilic/lipophilic balanced (HLB) resin with pure methanol (HLB-M), HLB resin with 2% (v/v) ammonia/methanol (HLB-N), and Bond Elut PPL (Priority PolLutant) resin with methanol (PPL), were compared for the isolation of HULIS from atmospheric aerosols. The HLB-N and PPL methods efficiently recovered Suwannee River fulvic acid (SRFA) and were excellent for quantifying HULIS at low levels in aerosols. All three SPE methods were favorable for the elution of aromatic and strongly UV-absorbing compounds. However, the chemical structures and molecular compositions of the HULIS isolated by the three methods showed some differences. The HULIS HLB-N and HULIS PPL fractions contained higher concentrations of aliphatic and aromatic C–H groups than did the HULIS HLB-M fraction, indicating that relative higher content of weak polar organic species in HULIS fractions isolated by the HLB-N and PPL methods than those isolated by the HLB-M method. Moreover, the HULIS HLB-N and HULIS PPL were both characterized by having lower relative abundance-weighted modified aromaticity index values and higher concentrations of S-containing compounds than the HULIS HLB-M , as indicated by Fourier transform ion cyclotron resonance mass spectrometry. Some N-containing structures were identified only in the HULIS HLB-N , suggesting that some of HULIS molecules were changed during the HLB-N treatment. Based on these comparisons of the three methods, we found that the PPL method serves equally good as compared to other two methods, and therefore, one can utilize PPL method also for HULIS isolation and characterization. • HLB-M, HLB-N, and PPL methods are comparatively investigated and estimated. • All SPE methods were favorable for high UV absorbance and aromatic compounds. • Some HULIS molecules were changed during the HLB-N treatment. • The PPL method serves equally good for HULIS isolation and characterization. [ABSTRACT FROM AUTHOR]

A series of novel ZnO/CuO n-n heterojunction photocatalysts were synthesized with a microwave assisted method. The structures, morphologies, optical properties, and chemical states of these prepared photocatalysts were systematically characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV–vis diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The results indicated that the crystalline structures and morphologies of ZnO and ZnO/CuO are both quasi-sphere shape wurtzite structures. The photocatalytic activities of ZnO/CuO heterojunction were evaluated by the degradation of Acid Orange 7 under simulated solar light irradiation. The results indicated that the ZnO/CuO n-n heterojunctions all have higher photocatalytic activities than the pure ZnO and the ZnO/CuO(2) sample with 2% of CuO exhibits the highest performance for degradation of Acid Orange 7. These could be due to the effective enhancement of electron-hole separation and weaken charge transfer resistance in ZnO/CuO n-n heterojunction, as indicated by their photoluminescences, the electrochemical impedance spectra, and photocurrent responses. Finally, Z-scheme electron transfer mechanism was proposed as the major photocatalytic mechanism of ZnO/CuO materials. [ABSTRACT FROM AUTHOR]

This study was conducted to estimate the current prevalence of hypertension, cardiovascular condition and hearing difficulty of workers exposure to occupational noise, and to analyze any associations between these abnormal signs and occupational noise exposure. The subjects included 5205 noise-exposed workers. Workers with high noise exposure were more likely to have a higher threshold value than low exposure ones (P < 0.05). Subjects in the high exposure group had a significantly higher risk of hypertension and hearing loss than the ones in low exposure group. Between the ages of 30 and 45, high-level occupational noise exposure led to a significantly raising risk of both hypertension (Adjusted OR = 1.59, 95% CI, 1.19–2.11) and hearing loss (Adjusted OR = 1.28, 95% CI, 1.03–1.60) when comparing to low-level noise exposure. In male workers, the prevalence of hearing difficulty in high exposure group was approximately 1.2 times worse than in low group (P = 0.006). In addition, exposure to high noise level demonstrated a significant association with hypertension and hearing loss when the duration time to occupational noise was longer than 10 years. Hypertension and hearing difficulty is more prevalent in the noise-exposed group (higher than 85 dB[A]). Steps to reduce workplace noise levels and to improve workplace-based health are thus urgently needed. [ABSTRACT FROM AUTHOR]

Co3O4/carbon hybrid hollow nanospheres (hs-Co3O4/C) with an empty cavity and a thin shell, were synthesized starting from the pectin and cobalt acetate via cross-linking deposition at room temperature and post-calcination. The hierarchical structure is constructed from the interconnected nanoparticles in the residual carbon matrix, and the carbon content can be adjusted by changing the calcination temperature. The gas sensor based on hs-Co3O4/C calcined at 300 °C in air shows high response towards 50 ppm of H2S (S = 95.5) and good selectivity at a low working temperature (92 °C). The detection limit is as low as 0.1 ppm. The non-enzymatic glassy carbon electrode based sensor constructed from the same material exhibits excellent electrocatalytic activity for H2O2 with the sensitivity of 405.8 μA∙mM∙cm−2 at 0.3 V (vs. SCE) in alkaline solution. The chronoamperometric response time is < 3 s and the detection limit (at S/N = 3) is 0.30 μM. The good sensing performances are attributed to the synergetic effect of unique hollow nanostructure and appropriate amount of carbon in the hybrid material. The porous nanostructure can increase the mass transfer efficiency, and the cross-linked nanoparticles with good crystallinity also improve the conductivity of materials. The presence of carbon enhances the charge transfer ability and increases the specific surface, thereby improving the sensor performance.Schematic illustration of the formation of hollow Co3O4 nanospheres composited with pectin-derived carbon. The material displays excellent selectivity for H2S gas and in non-enzymatic detection of dissolved H2O2. [ABSTRACT FROM AUTHOR]

Background: Noise induced hearing loss (NIHL) is a polygenic disease involving both genetic and environmental factors, and is one of the most important occupational health hazards worldwide. To date, the influence of Notch1 variants on the risk to develop NIHL has not been illuminated. This study was conducted to explore the effects of Notch1 polymorphisms on individual susceptibility to NIHL. Methods: A total of 2689 industrial workers from one textile factory in east China were recruited to participate in the current study. Venous blood was collected, basic clinical data was obtained by questionnaires and pure-tone audiometry (PTA) tests were conducted by specialist physicians. Next we performed genotyping of three selected SNPs (rs3124594, rs3124599 and rs3124603) in the Notch1 gene in 535 NIHL patients and 535 controls. Subsequently, the main effects of the genotypes and their interactions were evaluated. Results: Our results revealed that individuals with a GG of rs3124594, TT of rs3124603 (OR = 4.70 and 1.59 respectively) and the haplotype AAC (rs3124594-rs3124599-rs3124603) (OR = 14.95) were associated with an increased risk of NIHL in our study cohort. Stratified analysis showed that an increased NIHL risk was found in individuals exposed to work related noise for ≤16 years that also had the rs3124594 GG or rs3124603 CT/TT genotype with an OR of 4.20 and 1.73 respectively. Multifactor dimensionality reduction analysis indicated that rs3124594, rs3124599 and rs3124603 interacted with each other and were related to an increased risk to develop NIHL (OR = 3.60). Conclusions: The genetic polymorphisms rs3124594 and rs3124603 within the Notch1 gene are associated with an increased risk of NIHL in a Chinese population and could potentially be used as biomarkers for NIHL in noise exposed workers. [ABSTRACT FROM AUTHOR]

This study was conducted to explore the effects of DNMT1 and DNMT3A polymorphisms on susceptibility to noise-induced hearing loss (NIHL) in Chinese workers. A total of 2689 industrial workers from a single textile factory were recruited. Venous blood was collected, as were questionnaire and pure-tone audiometry (PTA) data by specialist physicians. Four selected SNPs (rs7578575, rs749131, rs1550117, and rs2228611) in DNMT1 and DNMT3A were genotyped in 527 NIHL patients and 527 controls. Then, main effects of the genotypes and their interactions were evaluated. Results revealed that the GG genotype at rs749131 and the AG/GG genotypes at rs1550117 and rs2228611 [odds ratio (OR) = 1.87, 2.57, and 1.98 respectively], as well as the haplotypes AGGG and TGGA (rs7578578-rs749131-rs1550117-rs2228611) (OR = 1.35 and 1.56, respectively) were associated with an increased risk of NIHL in the Chinese population. Multifactor dimensionality reduction analysis indicated that rs7578575, rs749131, and rs2228611 interact and are related to increased NIHL risk (OR = 1.63). The genetic polymorphisms rs749131 G, rs1550117 G, and rs2228611 G within the DNMT1 and DNMT3A genes are associated with an increased risk of NIHL in the Chinese population and have the potential to act as biomarkers for noise-exposed workers. [ABSTRACT FROM AUTHOR]

Background: Condylomata acuminata (genital warts) is the most common sexually transmitted disease, and imiquimod is the sole FDA-approved medication for combating this condition. Vitiligo associated with imiquimod treatment of condylomata acuminata is rare.Case Presentation: A 28-year-old male with condylomata acuminata of the penis presented to our clinic. After removing his condylomata acuminata, we advised him to use imiquimod 5% cream to prevent relapse. When he presented to our clinic again about 12 weeks later, he complained of vitiligo patches on his penis and scrotum. Physical examination showed vitiligo patches involving the glans penis, shaft of the penis, and scrotum, and remaining pigmented areas within the plaques of vitiligo.A skin biopsy of the dorsal surface of the penis showed a complete absence of melanocytes and melanin granules in the basal layer; the dermis was normal.Conclusion: This is the first report of a case of imiquimod-induced vitiligo diagnosed by histopathological examination. This adverse effect should be considered when dermatologists prescribe this medication. [ABSTRACT FROM AUTHOR]