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Abstract In this study, the removal effect of arsenic(V) was compared with different lead-containing substances, and the process of arsenic(V) removal with lead oxide was optimized. The results showed that As(V) removal efficiencies with lead powder, lead oxide, lead hydroxide and lead nitrate were 26.5%, > 99.9%, 98.5% and 96.3% at lead/arsenic(Pb/As) molar ratio of 2.12, respectively. Arsenic(V) removal with lead and its compounds was mainly based on the formation of mimetite. The removal of arsenic with lead oxide did not introduce impurity anions, and the crystallization performance and stability of the precipitate were relatively better than those of the precipitates obtained with other lead-containing substances. The crystallization performance of the precipitate was obviously improved when lead oxide was added twice. Using pH-conditioning in the process of arsenic removal, the residual lead in the solution could be removed via the co-precipitation of the hydrolysis of Pb2+ with mimetite. The highest As(V) leaching concentration of As—Pb precipitates was 0.2 mg/L at the pH of 1.9–12.3 with the leaching time of 1–48 h, and the stability of As—Pb precipitates could be improved by washing with dilute nitric acid. Lead oxide could be used as an effective reagent of arsenic removal in aqueous chloride solution. Highlights • Removal effect of arsenic(V) was compared with different lead-containing substances. • Arsenic(V) removal with lead oxide did not introduce impurity anions. • Stability of precipitates was improved by changing the addition ways of lead oxide. • The residual lead was removed by pH-conditioning in the process of arsenic removal. [ABSTRACT FROM AUTHOR]

RATIONALE Impurity analysis plays an important role to guarantee the quality and safety of pharmaceuticals. However, identification of impurities remains challenging, especially for those unknown or at trace levels. We present an integrated approach to detect and characterize the trace impurities in drugs. METHODS Based on liquid chromatography-tandem mass spectrometry (LC-MS/MS), an approach integrating automatic impurity screening method using multiple mass defect filters (MMDFs) and background subtraction (BS) was developed. This approach was used to acquire the structural and semi-quantitative information in a single sample run, and even to discover the impurity signals submerged by background and drug ions. This approach was illustrated by the comprehensive impurity analysis of levofloxacin. RESULTS This approach was sensitive to detect impurities at the level of 0.02% with respect to levofloxacin concentration. Nineteen impurities were detected, fourteen of which were structurally characterized and eight impurities were reported for the first time. Impurity profiles of levofloxacin drug substances and degradation samples were obtained reliably. A plausible degradation pathway of levofloxacin was proposed including descarboxyl reaction under acid, piperazinyl ring cleavage degradation under light, and N-oxidation under oxidative condition. CONCLUSIONS The generic approach integrating LC-MS/MS and an automatic impurity screening method was developed for the detection, characterization and monitoring of impurities, especially those unknown or at trace levels. This approach was demonstrated to be rapid, sensitive and automatic for impurity profiling of drugs. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The oxidation of arsenic from As(III) to As(V) during copper electrorefining was studied. Experimental results showed that during copper electrorefining, the precipitation of impurities As, Sb and Bi in the electrolyte has strong relation with the oxidation. When As(III) and AsT were 5.00g/L and 10.00g/L respectively in the initial electrolyte, after copper electrolysis carried out with current density 235A/m2 at 65°C for 168h, the concentrations of Sb and Bi were decreased 35.0% and 18.2% respectively, while without As(III) in the initial electrolyte, under the same conditions, the concentrations of Sb and Bi weren''t decreased but increased 12.5% and 9.1% respectively. It was found that the oxidation of arsenic from As(III) to As(V) plays an important role in the precipitation of impurities As, Sb and Bi in copper electrolyte as well, and the oxidation is applicable to the pseudo-first order kinetic model. [Copyright &y& Elsevier]

• Efficient separation and recovery of arsenic and alkali were achieved. • Low consumption of sulfuric acid in the process of deep alkali removal. • The products recovered from arsenic-alkali solution were Na 2 CO 3 and As 2 O 3. • No arsenic-alkali mixed salts were produced in the separation process of arsenic and alkali. For the comprehensive utilization of antimony smelting arsenic-alkali residue, there are some problems such as the incomplete separation and low recoveries of arsenic and alkali, and the formation of arsenic-alkali mixed salts with secondary pollution. In order to solve these problems, the leaching solution of arsenic-alkali residue (arsenic-alkali solution) was used as a raw material in this study, and a novel process of twice alkali recovery with CO 2 , deep alkali removal with H 2 SO 4 , As(V) reduction with SO 2 and evaporation concentration to recover arsenic was proposed to dispose of the arsenic-alkali solution. The total recovery of alkali was 87.8% by twice alkali recovery from the arsenic-alkali solution. After washing and thermal decomposition of crude NaHCO 3 , the obtained Na 2 CO 3 product can be used as the reagent of arsenic removal in the refining process of crude antimony. In the process of deep alkali removal, compared with the direct treatment, the consumption of H 2 SO 4 after twice alkali recovery was markedly reduced from the arsenic-alkali solution, and also no mirabilite was precipitated. The total recovery of arsenic was 80.6% in the process of arsenic recovery, and the purity of As 2 O 3 in arsenic trioxide product reached 95.2% after washing, which meets the third grade standard of arsenic trioxide (GB 26721–2011). This process realizes the efficient separation and recovery of arsenic and alkali from the arsenic-alkali solution, and also no arsenic-alkali mixed salts are produced. [ABSTRACT FROM AUTHOR]

Arsenic-alkali residue is a hazardous waste produced by the refining process of crude antimony in antimony smelting, and contains highly toxic sodium arsenate and a large number of residual alkali. In this study, aiming at the problems of the low recoveries and incomplete separation of arsenic and alkali, the secondary pollution of arsenic-alkali mixed salts and the insufficient utilization of valuable resources in the treatment process of arsenic-alkali residue, a new process of antimony enrichment with water leaching, twice alkali recovery with CO 2 , selenium recovery with acidification and arsenic recovery with SO 2 reduction and evaporation concentration was proposed to dispose arsenic-alkali residue. The results showed that the leaching efficiencies of Sb, As, Se and alkali in arsenic-alkali residue were 1.8, 98.4, 97.9 and 100% by hot water leaching, respectively. Alkali was recovered with CO 2 from arsenic-alkali solution and the direct recovery was 87.8%. In addition, the purity of Na 2 CO 3 product was higher than 90% and As content in product was controlled below 0.2%. Deep alkali removal and efficient selenium recovery were achieved by acidification from the solution after alkali recovery, the direct recovery of Se was 80.6%, and the purity of crude selenium was 81.7%. Arsenic was recovered from the solution after selenium removal and the direct recovery was 79.4%, and the quality of As 2 O 3 product reached the third grade standard of arsenic trioxide (GB 26721-2011). This process realizes the efficient recovery of alkali, selenium and arsenic in arsenic-alkali residue, and also does not produce arsenic-alkali mixed salts and wastewater. • A new process was proposed to dispose antimony smelting arsenic-alkali residue. • The efficient recovery of alkali, selenium and arsenic was achieved. • Se was recovered in the form of elemental selenium without adding reducing agent. • The recycling process is clean and environmentally friendly. [ABSTRACT FROM AUTHOR]

Purpose: To assess the associations of corneal biomechanical properties as measured by the Corvis ST with refractive errors and ocular biometry in an unselected sample of young adults. Methods: A total of 1645 healthy university students underwent corneal biomechanical parameters measurement by the Corvis ST. The refractive status of the participants was measured using an autorefractor without cycloplegia. Ocular biometric parameters were measured using the IOL Master. Results: After adjusting for the effect of age, sex, biomechanical-corrected intraocular pressure and central corneal thickness, axial length was significantly associated with A1 velocity (A1v, β = -10.47), A2 velocity (A2v, β = 4.66), A2 deflection amplitude (A2DeflA, β = -6.02), HC deflection amplitude (HC-DeflA, β = 5.95), HC peak distance (HC-PD, β = 2.57), deformation amplitude ratio max (DA Rmax, β = -0.36), Ambrósio′s relational thickness to the horizontal profile (ARTh, β = 0.002). For axial length / corneal radius ratio, only A1v (β = -2.01), A1 deflection amplitude (A1DeflA, β = 2.30), HC-DeflA (β = 1.49), HC-PD (β = -0.21), DA Rmax (β = 0.07), stress–strain index (SSI, β = -0.29), ARTh (β < 0.001) were significant associates. A1v (β = 23.18), HC-DeflA (β = -15.36), HC-PD (β = 1.27), DA Rmax (β = -0.66), SSI (β = 3.53), ARTh (β = -0.02) were significantly associated with spherical equivalent. Conclusion: Myopic eyes were more likely to have more deformable corneas and corneas in high myopia were easier to deform and were even softer compared with those in the mild/moderate myopia. [ABSTRACT FROM AUTHOR]

• A combined process was proposed to purify crude As 2 O 3 and prepare high-purity As 2 O 3. • Above 95% As was extracted from crude As 2 O 3 by acidic oxidation leaching. • As(V) reduction process was controlled by both diffusion and chemical reaction. • The purification process is efficient and environmentally friendly. In this study, a combined process of acidic oxidation leaching and SO 2 reduction was proposed to purify crude As 2 O 3 recovered from antimony smelting arsenic-alkali residue. The effects of various process factors on crude As 2 O 3 leaching were investigated based on the thermodynamic analysis. The results showed that the leaching efficiency of arsenic was 95.5% when crude As 2 O 3 was leached with the mixed solution of H 2 SO 4 and H 2 O 2 under the conditions: the H 2 O 2 /As(III) molar ratio (n (H 2 O 2): n (As(III))) of 0.93, leaching temperature of 75 ℃, leaching time of 90 min and liquid-solid ratio of 4:1. The kinetic study of As(V) reduction with SO 2 gas showed that the reduction process conformed to the first-order gas/liquid reaction kinetics, and was controlled by both diffusion and chemical reaction with an apparent activation energy of 16.69 kJ mol−1. Arsenic could be directly recovered in the form of As 2 O 3 from leaching solution by SO 2 reduction, and the obtained product reached the standard of As 2 O 3 -1 (GB 26721-2011) after further purification. The direct recovery of arsenic was 85.8% after twice purifications for crude As 2 O 3. In addition, no arsenic-containing wastes were produced in the purification process. Overall, this process is efficient and clean for the purification of crude As 2 O 3. [ABSTRACT FROM AUTHOR]

Research indicates that sleep problem is a behavioral risk factor of obesity. However, few research have applied a multi-dimensional approach to investigate the relationship between sleep health and adiposity. Therefore, the current study aimed to examine the associations of sleep characteristics (duration, quality) and chronotype with overweight/obesity as measured by body mass index. Data were obtained from 2014 college students from the Dali University in the Yunnan province of China in the year 2021. Sleep characteristics and chronotype were measured using self-reported questionnaires. The presence of overweight/obesity was assessed by anthropometric measurements. Multiple logistic regression models and restricted cubic spline hazard models were established to examine associations between sleep characteristics, chronotype and adiposity. After adjusting for demographic characteristics and other obesity-related behavioral risk factors, evening type was positively associated with overweight/obesity, and an L-shaped dose-effect relationship was observed between chronotype scores and the presence of overweight/obesity. However, sleep duration and quality were not associated with the presence of overweight/obesity in the logistic regression models and restrictive cubic splines models. This study indicated that Chinese college students who had the evening chronotype were more likely to be affected by overweight/obesity. Chronotype as an important dimension of sleep health should be incorporated in obesity intervention programs. [ABSTRACT FROM AUTHOR]

Presenting a chain mediation model to investigate whether mobile phone dependence results in a reduction in health-related quality of life (HRQoL) among Chinese college students, through the mediating effect of chronotype and sleep quality.A cross-sectional survey was conducted on students from a Chinese university using a validated structured questionnaire.2014 freshmen.The study measured the students’ level of mobile phone dependence using the Self-rating Questionnaire for Adolescent Problematic Mobile Phone Use. Chronotype and sleep quality were measured by the Chinese version of the Morningness-Eveningness Questionnaire (MEQ) and the Pittsburgh Sleep Quality Index (PSQI), respectively. HRQoL was evaluated using the five-level EuroQol five-dimensional questionnaire (EQ-5D-5L), including a descriptive system and a visual analog scale (VAS).Descriptive statistical analysis, correlation analysis, and mediation analysis.Mobile phone dependence had a significant negative effect on HRQoL as indicated by both the EQ-5D-5L index score and EQ-VAS score (P < .001 for both). Additionally, it was found to significantly predict chronotype (MEQ score) (β = −.546, P < .001) and sleep quality (PSQI score) (β = .163, P < .001). Chronotype negatively predict sleep quality (β = −.058, P < .001), and sleep quality was a significant negative predictor of HRQoL (EQ-5D-5L index score, β = −.008, P < .001; EQ-VAS score, β = −1.576, P < .001).Mobile phone dependence negatively impacts students’ HRQoL through chronotype and sleep quality, and there is a chain mediating effect. Students should consider making lifestyle changes to improve their HRQoL and promote health. [ABSTRACT FROM AUTHOR]

The fruits of Siraitia grosvenorii are considered to be health-promoting because of the diversity of their bioactive ingredients. In the present study, a screening method, using high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC-Q-TOF-MS) combined with a screening strategy, has been established. The technology was used to systematically screening the targeted metabolites, primarily from the complex matrix of S. grosvenorii . The compounds were then identified by their exact masses and characteristic fragment ions, in comparison with the fragmentation behaviors of 19 references. Finally, 122 compounds, including 53 flavonols and flavonol glycosides, 59 triterpene glycosides and 10 siraitic acid glycosides, were screened and identified in 10-, 50- and 80-day fruits, roots, stems and leaves of S. grosvenorii . 98 of them were reported for the first time. Additionally, the distribution of all identified components in different parts of the plant was determined and metabolic networks for flavonol and triterpene glycosides were proposed. [ABSTRACT FROM AUTHOR]

The ATP-dependent Lon protease is involved in many physiological processes. In bacteria, Lon regulates pathogenesis and, in yeast, Lon protects mitochondia from oxidative damage. However, little is known about Lon in fungal phytopathogens. MAP1, a homologue of Lon in Magnaporthe oryzae, was recently identified to be important for stress resistance and pathogenesis. Here, we focus on a novel pathogenic pathway mediated by MAP1. Based on an interaction system between rice and a tandem affinity purification ( TAP)-tagged MAP1 complementation strain, we identified 23 novel fungal proteins from infected leaves using a TAP approach with mass spectrometry, and confirmed that 14 of these proteins physically interact with MAP1 in vivo. Among these 14 proteins, 11 candidates, presumably localized to the mitochondria, were biochemically determined to be substrates of MAP1 hydrolysis. Deletion mutants were created and functionally analysed to further confirm the involvement of these proteins in pathogenesis. The results indicated that all mutants showed reduced conidiation and sensitivity to hydrogen peroxide. Appressorial formations were not affected, although conidia from certain mutants were morphologically altered. In addition, virulence was reduced in four mutants, enhanced (with lesions forming earlier) in two mutants and remained unchanged in one mutant. Together with the known virulence-related proteins alternative oxidase and enoyl- CoA hydratase, we propose that most of the Lon-interacting proteins are involved in the pathogenic regulation pathway mediated by MAP1 in M. oryzae. Perturbation of this pathway may represent an effective approach for the inhibition of rice blast disease. [ABSTRACT FROM AUTHOR]