Terbium Vanadate Nanowires-Based Electrochemical Sensors for Mercury Ions.

Terbium vanadate nanowires were synthesized via a facile chemical approach using sodium vanadate and terbium chloride. Morphology, structure, composition, and electrochemical characteristics of the terbium vanadate nanowires were investigated by different techniques. Terbium vanadate nanowires with single crystalline tetragonal TbVO4 phase possess smooth surface and flat tips. The length of the nanowires is longer than 5 µm, and diameter is 40-100 nm. Terbium vanadate nanowires modified electrode was used for trace-level mercury ions (Hg2+) detection. One well-defined stripping peak exists at - 0.34 V at the terbium vanadate nanowires modified electrode in 0.1 mM Hg2+ solution. Buffer solution pH value, deposition time, deposition potential, and standing time are pH = 1, 150 s, - 1.5 V, and 60 s, respectively. Detection limit for Hg2+ detection is 0.18 nM, and linear range is 0.01-100 µM. The proposed terbium vanadate nanowires modified electrode exhibits significant selectivity, stability, and reproducibility toward Hg2+. The usefulness of the developed sensor based on the terbium vanadate nanowires modified electrode was verified by Hg2+ detection in real samples.

Controllable synthesis of BiPr composite oxide nanowires electrocatalyst for sensitive L-cysteine sensing properties.

BiPr composite oxide nanowires with rhombodedral Bi1.35Pr0.65O3, monoclinic Bi2O3and monoclinic Pr5O9phases were synthesized via a facile sodium dodecyl sulfate (SDS) assisted hydrothermal route. The obtained nanowires were characterized by x-ray diffraction, electron microscopy, x-ray photoelectron spectroscopy and electrochemical measurements. The BiPr composite oxide nanowires possess poly-crystalline structure, semi-circular tips, diameter and length of 20-100 nm and several micrometers, respectively. SDS is essential for the formation of the BiPr composite oxide nanowires which can be explained by a SDS assisted hydrothermal growth process. Electrochemical impedance spectroscopy shows that the electrons are easier to transfer by the surface of the BiPr composite oxide nanowires modified glassy carbon electrode (GCE) than bare GCE. The BiPr composite oxide nanowires modified GCE possesses good electro-catalytic activity for L-cysteine detection with a pair of quasi-reversible cyclic voltammetry peaks at +0.04 V and -0.72 V for the oxidation and reduction of L-cysteine, respectively. The roles of the scan rate, electrolyte species and L-cysteine concentration on the electrochemical responses of L-cysteine at the nanowires modified GCE were systematically analyzed. The BiPr composite oxide nanowires modified GCE presents a linear response range from 0.001 to 2 mM and detection limit of 0.27µM, good reproducibility and stability.

Higher levels of nonylphenol were found in human urine and drinking water from rural areas as compared to metropolitan regions of Wuhan, China.

The suspected endocrine disruptor nonylphenol (NP) is closely associated with anthropogenic activities; therefore, studies on this compound have been clustered in urban areas. This study investigated the NP concentrations in drinking water sources (n = 8), terminal tap water (n = 36), and human urine samples (n = 127) collected from urban and rural areas in Wuhan, China. The mean concentrations of NP measured in drinking water sources in urban and rural areas were 92.3 ± 7.5 and 11.0 ± 0.8 ng/L (mean ± SD), respectively, whereas the mean levels in urban and rural tap waters were 5.0 ± 0.7 and 44.2 ± 2.6 ng/L (mean ± SD), respectively. Nevertheless, NP was detected in 74.1% and 75.4% of the human urine samples from urban and rural participants, with geometric mean concentrations of 0.19 ng/mL (0.26 µg/g creat) and 0.27 ng/mL (0.46 µg/g creat), respectively. Although the NP concentrations measured in the drinking water sources of urban areas were significantly higher than those in rural areas (P < 0.05), the tap water and urine NP concentrations measured in urban areas were unexpectedly lower than those of rural areas (P < 0.05). Additionally, this investigation showed that the materials comprising household water supply pipelines and drinking water treatment processes in the two areas were also different. Our results indicated that the levels of exposure to NP in drinking water and human urine in rural areas were not necessarily lower than those in urban areas. Thus, particular attention should be paid to rural areas in future studies of NP.

Association of body mass index with serum anti-Müllerian hormone and inhibin B levels among 8323 women attending a reproductive medical center: a cross-sectional study.

PURPOSE: To assess the association of body mass index (BMI) with serum anti-Müllerian hormone (AMH) and inhibin B (InB) levels among women attending a reproductive medical center. METHODS: We conducted a cross-sectional study of 8323 women (96.4% were Han race) without polycystic ovary syndrome (PCOS) from the reproductive medical center of Tongji Hospital in Wuhan, China for assisted reproductive technology treatment between January 2016 and May 2018. For each participant, BMI and levels of serum AMH and InB were measured at entry by trained clinical technicians. Multivariate linear regression models were used to quantitatively estimate the associations of continuous and categorical BMI with serum AMH and InB levels. RESULTS: Each 1 kg/m2 increase in BMI was significantly associated with a 1.02% (95% CI: 0.40, 1.65%) and 3.59% (3.11, 4.06%) reduction in AMH and InB levels, respectively. No departure from linearity was observed for either AMH or InB (both P for nonlinear trend >0.05). Overweight and obesity were significantly associated with a 6.01% (0.70, 11.04%) and 18.64% (2.29, 32.26%) reduction in AMH level, and were significantly associated with a 18.80% (15.23, 22.23%) and a 35.44% (25.47, 44.08%) reduction in InB level, respectively. In addition, the association between BMI and AMH level was significantly stronger among women ≥32 years. CONCLUSIONS: BMI was linearly and inversely associated with AMH and InB levels among women without PCOS. Both overweight and obesity were significantly associated with lower AMH and InB levels.

Urine Nitric Oxide Is Lower in Parents of Autistic Children.

Parents raising children with autism spectrum disorder (ASD) usually carry on their daily life under tremendous stress, but limited empirical research has been devoted to this population. It is known that parents' health status directly impacts therapeutic outcome of ASD children. As an important regulator in cardiovascular, nervous and immune systems, nitric oxide (NO) levels haven't been reported in parents of ASD children yet. In this study, we measured urine nitrite and nitrate from 43 ASD parents (ASD-P), and 43 healthy adults in the same range of age (Control) who didn't have any ASD descendants. Comparison between the ASD-P and Control groups showed that NO 2 - , NO 3 - , and NO 2 - / NO 3 - were all significantly lower in the ASD-P group. Analysis on the interaction effect of sex and group indicated that urine NO 3 - of mothers in ASD-P was lower than that in females of the Control group, but no significant difference was observed between males in both groups. It is for the first time that urine nitric oxide metabolites (nitrite, nitrate) levels were precisely reported to differentiate parents of autistic children from other adults without ASD descendants. This phenomenon suggests that parents (especially mothers) of autistic children might have experienced more mental and physical stressors, which led to decreased NO levels during metabolism. Further investigations are necessary to uncover the etiology of low urine NO among parents of autistic children.

Assessment of different ventilation strategies on ventilation performance in immersed tunnels.

Investigations of ventilation in an immersed tunnel have recently drawn greater research attentions; however, analyses on the influence of vent design and tunnel width on ventilation performance have rarely been addressed. For the sake of the security of evacuees in an immersed tunnel fire, the influence of three vent designs and two immersed tunnel widths on mechanical ventilation performance during tunnel fires were numerically investigated using large eddy simulation. The pollutant gas flow characteristics in the tunnel after a fire were analyzed, and the pollutant gas exhaust efficiency based on the mass conservation of carbon monoxide in the smoke was proposed in this study. By comparing the smoke propagation, smoke distribution, and exhaust efficiency between three different vent designs, it was determined that the Top Vent Design has the best smoke exhaust effect, and the Sidewall Vent Design (with an activated vertical smoke screen) has a better smoke exhaust effect than the Sidewall Vent Design. The influences of the tunnel width and heat release rate of the fire on the ventilation effect were also investigated.

Short-Term Exposure to Ambient Air Pollution and Mortality From Myocardial Infarction.

BACKGROUND: Short-term exposure to ambient air pollution has been linked to occurrence of myocardial infarction (MI); however, only a limited number of studies investigated its association with death from MI, and the results remain inconsistent. OBJECTIVES: This study sought to investigate the association of short-term exposure to air pollution across a wide range of concentrations with MI mortality. METHODS: A time-stratified case-crossover study was conducted to investigate 151,608 MI death cases in Hubei province (China) from 2013 to 2018. Based on each case's home address, exposure to particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5), particulate matter with an aerodynamic diameter ≤10 µm (PM10), sulfur dioxide, nitrogen dioxide (NO2), carbon monoxide, and ozone on each of the case and control days was assessed as the inverse distance-weighted average concentration at neighboring air quality monitoring stations. Conditional logistic regression models were implemented to quantify exposure-response associations. RESULTS: Exposure to PM2.5, PM10, and NO2 (mean exposure on the same day of death and 1 day prior) was significantly associated with increased odds of MI mortality. The odds associated with PM2.5 and PM10 exposures increased steeply before a breakpoint (PM2.5, 33.3 µg/m3; PM10, 57.3 µg/m3) and flattened out at higher exposure levels, while the association for NO2 exposure was almost linear. Each 10-µg/m3 increase in exposure to PM2.5 (<33.3 µg/m3), PM10 (<57.3 µg/m3), and NO2 was significantly associated with a 4.14% (95% confidence interval [CI]: 1.25% to 7.12%), 2.67% (95% CI: 0.80% to 4.57%), and 1.46% (95% CI: 0.76% to 2.17%) increase in odds of MI mortality, respectively. The association between NO2 exposure and MI mortality was significantly stronger in older adults. CONCLUSIONS: Short-term exposure to PM2.5, PM10, and NO2 was associated with increased risk of MI mortality.

Preparation and Phase Change Performance of Graphene Oxide and Silica Composite Na2SO4·10H2O Phase Change Materials (PCMs) as Thermal Energy Storage Materials.

In this study, a novel nucleating agent composed of graphene oxide (GO) and silicon dioxide (SiO2) (GO-SiO2) is developed. GO is used as a skeleton material through which SiO2 nanomaterials are absorbed and subsequently incorporated into Na2SO4·10H2O phase change materials (PCMs). Furthermore, this study examines the phase change performance of the composite Na2SO4·10H2O materials. Fourier-transform infrared (FTIR) spectra confirmed the physical combination of GO with a SiO2 nanoparticles. Scanning electron microscope (SEM) results showed that the GO-SiO2 composite exhibited a layered structure and excellent dispersibility. The GO-SiO2 composite Na2SO4·10H2O PCMs displayed a low level of supercooling, i.e., about 1.2 °C with the addition of GO-SiO2 at 2.45 wt%. This was because the synergistic relation of the GO and the high dispersion SiO2, imparted more nucleation sites for Na2SO4·10H2O. Additionally, the prepared PCMs achieved high phase change latent heat and thermal conductivity, even under these conditions. The results show that the GO-SiO2 in the Na2SO4·10H2O exhibited advantageous application prospects for the improvement of the thermal performance of hydrate salts.

Association between ambient temperature and semen quality: A longitudinal study of 10 802 men in China.

Semen quality is a vital determinant for male fertility. The process of spermatogenesis is highly sensitive to fluctuations in temperature. However, the impact of ambient temperature on semen quality remains unclear. We aimed to quantitatively assess the association between ambient temperature and semen quality. Using data from Hubei provincial human sperm bank in Wuhan, China, we conducted a longitudinal study including 10 802 volunteers who lived in Wuhan and passed the initial physical examination for sperm donation between Mar 27, 2013 and April 9, 2018. Semen quality parameters including sperm concentration, total sperm number, total motility, progressive motility, total motile sperm count and progressively motile sperm count were determined in the sperm bank. We used linear mixed models to identify estimate changes of outcomes in relation to ambient temperature (i.e., air temperature and apparent temperature) exposure measured as the mean daily temperature during the 0-90 days before semen collection. Among 10 802 subjects who underwent 41 689 semen examinations, we observed inverted U-shaped exposure-response associations between air temperature exposure and all semen quality parameters, with an identical threshold exposure of 13 °C. For air temperature exposure <13 °C, each 5 °C lower temperature was significantly associated with 1.94 × 106/ml, 7.12 × 106, 0.77%, 0.81%, 6.48 × 106, and 5.87 × 106 decrease in sperm concentration, total sperm count, total motility, progressive motility, total motile sperm count and progressively motile sperm count, respectively. When air temperature exposure was ≥13 °C, each 5 °C higher temperature was significantly associated with 0.70 × 106/ml, 4.09 × 106, 1.01%, 1.06%, 4.31 × 106, and 4.20 × 106 decrease in sperm concentration, total sperm count, total motility, progressive motility, total motile sperm count and progressively motile sperm count, respectively. Age, BMI and smoking did not significantly modify these associations. Similar results were observed for apparent temperature. This study provides a comprehensive picture of nonlinear association between ambient temperature and semen quality, as well as an optimal temperature for the benefit of semen quality. Both lower and higher ambient temperature exposures compared with the optimal temperature were significantly associated with decreased semen quality. The findings highlight the needs and importance to reduce extreme ambient temperature exposures in maintaining optimal semen quality for men. Further investigation is warranted to determine the causality of the association and the underlying mechanisms.

AIDS related knowledge, attitude and behaviors of MSMin a gay bathhouse / 预防医学

Objective@#To learn the knowledge, attitude and behaviors of AIDS of men who have sex wth men ( MSM ) in a gay bathhouse, so as to provide evidence for AIDS prevention and control among MSM.@*Methods@#From April to June of 2017, the MSM in a gay bathhouse in Wuhan were investigated. Demographic information, awareness of AIDS related knowledge, attitude towards HIV infection, dating ways and purposes, and high-risk sexual behaviors were collected and analyzed.@*Results@#Among 278 MSM responded, 235 ( 84.53% ) were aware of the basic knowledge of AIDS. The awareness rates of " transfusion with HIV blood will be infected ", " sharing syringes with HIV infected people will be infected ", "proper use of condoms can reduce the spread of AIDS ", " only having sex with one partner ( or few partners ) can reduce the spread of AIDS " were more than 90%, while the awareness rate of " high risk of HIV infection in gay bathhouses " was only 56.12%. Most respondents cared about the HIV infection situation of MSM, accounting for 74.46% ( 207 cases ) ; most denied or did not know the condition of friends infected with HIV, accounting for 82.37% ( 229 cases ) . The main purpose of coming to gay bathhouses was to find sexual partners, accounting for 87.41% ( 243 cases ) . About 52.16% had sexual behaviors with both heterosexual and homosexual partners, and 66.21% of them did not often or never use condoms when having sex with heterosexual partners. @*Conclusions@#The MSM in a gay bathouse have lower awareness of HIV infection situation and their partners, both heterosexual and homosexual behaviors, and lower proportion of insisting on condom use.

Oxidative damage and OGG1 expression induced by a combined effect of titanium dioxide nanoparticles and lead acetate in human hepatocytes.

Titanium dioxide (TiO(2)) is a widely used nanomaterial that can cause biological damage through oxidative stress. At low concentrations, TiO(2) can interact with lead acetate (PbAc) to produce different toxic responses, compared with TiO(2) or PbAc alone. In this study, we utilized the following as indicators of toxic responses in human embryo hepatocytes (L02): reactive oxygen species (ROS), reduced glutathione (GSH), superoxide dismutase (SOD), and the DNA adducts 8-hydroxydeoxyguanosine (8-OHdG) and 8-oxoguanine DNA glycosylase homolog 1 (OGG1). These were used to evaluate the oxidative stress of TiO(2) (at 0.001, 0.01, 0.1, 1, and 10 µg mL(-1)) mixed with PbAc (1 µg mL(-1)) on L02 cells without photoactivation. Compared with the negative control (1‰ dimethyl sulfoxide), TiO(2) mixed with PbAc induced increased release of ROS (at 0.001, 0.01, 0.1, 1, 10 µg mL(-1) TiO(2)), intracellular SOD activity (at 0.1 and 0.01 µg mL(-1) TiO(2)), GSH levels (at 0.01-1 µg mL(-1) TiO(2)), 8-OHdG levels (at 1 and 10 µg mL(-1) TiO(2)), OGG1 expression (at 0.001-1 µg mL(-1) TiO(2)), and cytotoxicity (at 0.1, 1, and 10 µg mL(-1) TiO(2)) in L02 cells. There were no significant changes in ROS, GSH, SOD, 8-OHdG, or OGG1 levels when L02 cells were treated with TiO(2) alone or PbAc alone. These findings indicate that TiO(2) and PbAc in combination induce cytotoxicity and oxidative stress in L02 cells in the absence of photoactivation.

1-(2-Hy-droxy-benzo-yl)thio-semicarbazide hemihydrate.

The asymmetric unit of the title compound, C(8)H(9)N(3)O(2)S·0.5H(2)O, contains two thiosemicarbazide mol-ecules with the short distance of 3.521 (3) Šbetween the centroids of the benzene rings, and one water mol-ecule. In the two independent mol-ecules, the benzene rings and the thio-semicarbazone fragments are twisted at 9.2 (3) and 18.5 (3)°. An extensive three-dimensional hydrogen-bonding network, formed by inter-molecular N-H⋯O, N-H⋯S and O-H⋯O hydrogen bonds, consolidates the crystal packing.

N,N-Bis(pyridin-2-yl-methyl-idene)pyridine-2,6-dicarbohydrazide dimethyl-formamide monosolvate.

In the crystal of the title compound, C(22)H(22)N(8)O(3), the dicarbohydrazide mol-ecules are linked into a chain along [010] by C-H⋯N inter-actions involving the pyridyl N atoms and aromatic C-H groups. The DMF mol-ecule is hydrogen bonded with the amide N-H via N-H⋯O inter-actions. C-H⋯O inter-actions also occur.

Poly[[bis-(µ(2)-6-methyl-pyrazin-2-carboxyl-ato-κN,O:N)copper(II)] dihydrate].

In the title compound, {[Cu(C(6)H(5)N(2)O(2))(2)]·2H(2)O}(n), the Cu(II) ion (site symmetry ) is coordinated by two N,O-bidentate ligands and two N-monodentate ligands in a distorted CuO(2)N(4) octa-hedral geometry. Each anion acts as a bridge between two cations, thus forming a two-dimensional polymeric network parallel to the ab plane. The packing is consolidated by O-H⋯O hydrogen bonds. One of the O atoms of the ligand and both water mol-ecules are disordered.

N'-(2-Chloro-benzyl-idene)benzo-hydrazide.

The asymmetric unit of the title compound, C(14)H(11)ClN(2)O, contains two independent mol-ecules. In one mol-ecule, the two aromatic rings form a dihedral angle of 45.94 (16)°, while in the second mol-ecule this angle is 58.48 (16)°. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into two crystallographically independent sets of chains propagating along [001].

(E)-N'-[1-(4-Bromo-phen-yl)ethyl-idene]-2-hydroxy-benzohydrazide.

In the title compound, C(15)H(13)BrN(2)O(2), the two aromatic rings form a dihedral angle of 7.9 (1)° and an intra-molecular N-H⋯O hydrogen bond influences the mol-ecular conformation. In the crystal, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into chains propagated in [001]. The crystal packing exhibits also π-π inter-actions, which pair mol-ecules into centrosymmetric dimers with short inter-molecular distances of 3.671 (4) Šbetween the centroids of aromatic rings.

(E)-N'-(2-Furylmethyl-ene)benzo-hydrazide.

In the title compound, C(12)H(10)N(2)O(2), the dihedral angle between the benzene and furan rings is 52.54 (7)°. In the crystal, inter-molecular N-H⋯O hydrogen bonds and C-H⋯π inter-actions link the mol-ecules.

1,2-Bis(2-nitro-phen-yl)disulfane.

In the title compound, C(12)H(8)N(2)O(4)S(2), the dihedral angle between the two benzene rings is 67.82 (9)°. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules.

(E)-N'-(4-Methoxy-benzyl-idene)benzohydrazide.

In the title mol-ecule, C(15)H(14)N(2)O(2), the dihedral angle between the benzene rings is 5.93 (17)°. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains propagating in [010].

(E)-N'-[1-(4-Bromo-phen-yl)ethyl-idene]benzohydrazide.

The asymmetric unit of the title compound, C(15)H(13)BrN(2)O, contains two independent mol-ecules with different conformations; the two aromatic rings form dihedral angles of 32.4 (4) and 27.5 (4)° in the two mol-ecules. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link mol-ecules into chains propagating in [100].