Physical symptoms and mental health status in deep underground miners: A cross-sectional study.

The aim of the present study was to reveal the physical symptom changes and their correlations with mental health status in deep underground miners.A total of 286 deep underground miners completed a cross-sectional questionnaire study at China Pingmei Shenma mine complex. The questionnaire included sociodemographics, self-reported physical symptoms, underground adverse environmental factors, and the Symptom Checklist-90-Revised (SCL-90-R). Five environmental parameters of 1 deep mine were also measured.Data from 266 valid questionnaires were analyzed. The 3 most frequent complaints about underground adverse conditions were moisture [62.03% (165/266)], dim light [45.86% (122/266)], and high temperature [42.11% (112/266)]. Fatigue [40.22% (107/266)], hearing loss [34.96% (93/266)], and tinnitus [31.58% (84/266)] were reported to be the three most common physical symptoms. Insomnia was reported in 204 participants (76.69%) mainly due to the difficulty of falling asleep [42.35% (84/204)] and dreams [39.70% (81/204)]. Mean scores of SCL-90-R subscales including somatization, anxiety, phobic anxiety, psychoticism, and paranoid ideation were elevated compared to Chinese norms, while there was diminished interpersonal sensitivity. Univariate analyses indicated that the 3 most common physical symptoms were associated with poorer SCL-90-R scores. With increasing depth below ground, air pressure, relative humidity, CO2 concentration and temperature rose, while total gamma radiation dose-rate decreased.The physical and mental health status of deep underground miners was poorer than the general Chinese male population. Some adverse environmental factors were identified that may have influenced health status. Measures are suggested to improve the deep underground working environment.

[Comparative investigation of molecules releasing from intra-hollow calcium-alginate capsules using fluorimetry].

In this paper, the authors employ three different types of dye molecules, Nile red, Rhodamine 6G, fluorescein and a fluorescent protein-R-phycoerythrin (R-PE). The Rhodamine 6G is positively charged molecules, fluorescein is negatively charged molecules, and Nile red is neutral molecules. The R-phycoerythrins have either a net positive or negative charge which is balanced at the isoelectric point (4.22). It is negatively charged molecules also under our experimental condition. The Nile red, rhodamine 6G, fluorescein and R-phycoerythrin are trapped into alginate calcium hollow capsule respectively. The diffusion processes of those molecules from calcium alginate capsule to solution are measured based on a fluorescence method. The results indicate that electrical characteristics of encapsulated molecules have effect on their diffusion behaviors. The positively charged rhodamine 6G is well accordance with a model of control release from porous polymer membranes. The neutral molecules not only can be released from porous polymer framework, they also can directly dissolve out through polymer membrane. The electrostatic repulsion between fluorescein and negatively charged calcium alginate membranes will accelerate the molecular motion, which is propitious to molecules directly dissolving out through polymer membrane. Based on Fick's law of diffusion, R-PEs can be releases from porous polymer framework It shows the longest equilibrium time. Comparing neutral molecules, negatively and positively charge molecules show the stronger interaction on electric polymer membrane, which results in that the diffusion coefficients of rhodamine 6G and fluorescein are less than that of neutral molecule Nile red. The consequences obtained here should readily explain analogous control releasing behaviors of other functional molecules.

[A study of non-spectral interference of iron matrix and its mechanisms in ICP-AES analysis].

In the present paper non-spectral Interference of iron matrix whose concentration ranges from 0 to 5 mg x mL(-1) has been studied by using ICP-AES. And its mechanisms are discussed through calculating every terms of the interference function and investigating the relation between the values of them and Fe matrix concentration. The results show that in a certain concentration range (0-5 mg x mL(-1)) Fe matrix has no significant influence upon excitation temperature and electronic number density. Most of the elements' activity coefficient terms decreases with the increase of Fe matrix concentration. And the contribution of each term to the interference function is different according to atomic line and ionic line. It is the difference in ionization term between atomic line and ionic line that causes this.

[Antioxidant activity and spectroscopic behavior study with DNA of several Salen Mn(II), Eu(III) complexes].

Five kinds of Salen Mn(II) and two kinds of Eu(III) complexes were synthesized. Under the system of NBT/L-methionine, which creates and detects O2*-, the complexes of antioxidant activity were studied, and the conclusion revealed that all Mn(II) complexes have obvious antioxidant activity. The fluorescence study indicated that all the Salen metal complexes could bind with DNA, which shows their potential anticancer activity.

[An enzyme sensor for phenolic compounds analysis].

Phenolic analysis was established on the immobilized horseradish peroxidase (HRP) catalyzed oxidation reaction. It subsequently catalyzed oxidative coupling of phenol with 4-aminophenazone using aqueous hydrogen peroxide to form intensely colored products for spectrophotometric analysis. HRPs were trapped in sol-gel matrix in a mild procedure. The immobilized HRPs maintain almost identical enzymatic activity as those in solution. BET analysis indicates that the silica itself is a porous structure with the average pore diameter of 2.95 nm. It permits small size molecules i. e. hydrogen peroxide, phenol and 4-aminophenazone to diffuse into the matrix while large molecules like enzyme (HRP) remain in the pores. It thus allows a biocatalysis to occur and makes the most out of the enzymes encapsulated in the silica matrix to stand against leakage so that the immobilized horseradish peroxidase could be recycled. The method can be employed for 2-chlorophenol, 3-chlorophenol or 2,4-dichlorophenol analysis as well. The feasibility of recycle on immobilized enzyme is evaluated. Although enzymatic activities are obviously decreased after repeated utilization of 9 times, the method definitely offers a potential spectrophotometric biosensor for phenolic compounds analysis.

[Compositions and structure characterizations of coal tar refined soft pitch].

High temperature coal tar was used as raw materials, and was distilled to 280 degrees C for getting coal tar soft pitch. Then refined soft pitch was obtained by solvent extracting and subsequent settlement method. Its soft point was 32 degrees C; the group compositions consisted of 53.67% heptane soluble, 39.47% heptane insoluble but toluene soluble, 6.86% toluene insoluble and 0.06% quinoline insoluble. The relative average molecular weight was about 292. Its average molecular formula was C22.22 H16.32 N0.12 S0.06 O0.33; the total content of heteroatom was less than 1. IR analytic results showed that its heteroatom O existed in the R-O-R and Ar-O-R structure; its heteroatom N existed in the R-NH-R and -N=, with the latter being primary. Its average structure was obtained by improved Brown-Lander model: five-membered condensed rings. UV analysis indicated that the majority was linear arrangement, and the minority was surface arrangement; namely, the chemical structure of the samples was mainly the cata-condensed structure, while the minority was peri-condensation.

Optimizing the integrated pulsed amperometric multicycle step waveform for the determination of tetracyclines.

A method of modified integrated pulsed amperometric detection with multicycle step waveform (Multi-IPAD) following high-performance liquid chromatography (HPLC) was applied for the determination of tetracyclines (TCs) including dimethyltetracycline (DMTC), oxytetracycline (OTC) and tetracycline (TC). The key advantages of the Multi-IPAD are the abilities to enhance sensitivity and reproducibility and the ability to keep working electrode clean through the use of a high-frequent waveform alteration in integration step and the use of a cleaning potential, which is quite different from conventional three-step potential waveform. The analyses were carried out using the mobile phase of acetonitrile-water mixture solution (10:90, v/v) containing 1% perchloric acid on a C(18) column at a flow rate of 0.21 mL/min. The IPAD waveform parameters were optimized to maximize the signal-to-noise ratio (S/N) and successfully applied for the sensitive detection of TCs. The detection limits (S/N=3, 20 microL injected) were 0.07 mg/L for DMTC, 0.08 mg/L for OTC and 0.05 mg/L for TC. The peak height relative standard deviations (RSDs) of every compound for replicate injection (n=15) determined were below 4.6%.

Multi-walled carbon nanotubes as a solid-phase extraction adsorbent for the determination of chlorophenols in environmental water samples.

Multi-walled carbon nanotubes (MWCNs) are used as adsorbent for solid-phase extraction (SPE) of several chlorophenols (CPs). CPs were adsorbed on MWCNs cartridge, then desorbed with pH 10.0 methanol, finally determined by HPLC. Under the optimized conditions, detection limits of 0.08-0.8 ng mL(-1) were obtained. The method had been applied to analyze the five CPs in tap water and river water.

Studies on the electrochemical behavior of cytochrome c and its interaction with DNA at a Co/GC ion implantation modified electrode.

The electrochemical behavior of cytochrome c (cyt c) and its interaction with DNA at a Co/glassy carbon (GC) ion implantation modified electrode were studied by linear sweep and cyclic voltammetry. In 0.005 mol dm(-3) Tris-0.05 mol dm(-3) NaCl buffer solution (pH = 7.10), a sensitive reduction derivative peak of cyt c was obtained by linear sweep voltammetry. The peak potential was 0.032 V (SCE). The peak current was proportional to the concentration of cyt c. The electrode process was quasi-reversible with adsorption. The electrode reaction rate constant k and the electron transfer coefficient a of cyt c were 4.42 s(-1) and 0.47, respectively. AES and XPS experiments showed that Co was implanted into the surface of the GC electrode (GCE). The implanted Co formed Co-C, which catalyzed the reduction of cyt c. The reaction of DNA with cyt c led to an electrochemically active complex, which resulted in an increase in the reduction current of cyt c. After adding DNA into the solution containing cyt c, the electrode process was still quasi-reversible with adsorption.

Membrane chromatographic method for the rapid purification of vitellogenin from fish plasma.

A membrane chromatographic method was developed for the rapid purification of vitellogenin (Vtg) from the plasma of 17beta-estradiol induced loach (Misgurnus angaillicaud atus) and carp (Cyprinus carpio). The time required for the proposed procedure is less then 10 min at a flow-rate of 5 ml/min of the mobile phase, and 0.5 ml of fish plasma could be separated in one cycle. Multistep gradient elution was more suitable for the separation than linear gradient elution. Under optimized conditions, a single Vtg peak can be obtained and its identity was confirmed by SDS-PAGE and gel-permeation chromatography assessment. This method is rapid and easy to operate compared to conventional HPLC and FPLC columns for Vtg separation.

[Study on enhancing effect of ethanol in lower power ICP].

The effects of ethanol on physical propesties (density, viscosity, surface tension) of sample solution, plasma temperature and electron number density in the ICP were investigated. Detection limits of varying elements in ethanol-water system were determined. The experimental results showed that the gas temperature, excitation temperature and electron number density were lower than those in water solution, the electron temperature and ionization temperature were slightly reduced, while the velocity of aerosol to the plasma increased. The lower detection limits of rare earth elements were observed. The detection limits of other elements were the same as those with water solution. The mechanism of the enhancing effect was discussed.