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Calpains have been implicated in heart diseases. While calpain-1 has been detrimental to the heart, the role of calpain-2 in cardiac pathology remains controversial. In this study we investigated whether sustained over-expression of calpain-2 had any adverse effects on the heart and the underlying mechanisms. Double transgenic mice (Tg-Capn2/tTA) were generated, which express human CAPN2 restricted to cardiomyocytes. The mice were subjected to echocardiography at age 3, 6, 8 and 12 months, and their heart tissues and sera were collected for analyses. We showed that transgenic mice over-expressing calpain-2 restricted to cardiomyocytes had normal heart function with no evidence of cardiac pathological remodeling at age 3 months. However, they exhibited features of dilated cardiomyopathy including increased heart size, enlarged heart chambers and heart dysfunction from age 8 months; histological analysis revealed loss of cardiomyocytes replaced by myocardial fibrosis and cardiomyocyte hypertrophy in transgenic mice from age 8 months. These cardiac alterations closely correlated with aberrant autophagy evidenced by significantly increased LC3BII and p62 protein levels and accumulation of autophagosomes in the hearts of transgenic mice. Notably, injection of 3-methyladenine, a well-established inhibitor of autophagy (30 mg/kg, i.p. once every 3 days starting from age 6 months for 2 months) prevented aberrant autophagy, attenuated myocardial injury and improved heart function in the transgenic mice. In cultured cardiomyocytes, over-expression of calpain-2 blocked autophagic flux by impairing lysosomal function. Furthermore, over-expression of calpain-2 resulted in lower levels of junctophilin-2 protein in the heart of transgenic mice and in cultured cardiomyocytes, which was attenuated by 3-methyladenine. In addition, blockade of autophagic flux by bafilomycin A (100 nM) induced a reduction of junctophilin-2 protein in cardiomyocytes. In summary, transgenic over-expression of calpain-2 induces age-dependent dilated cardiomyopathy in mice, which may be mediated through aberrant autophagy and a reduction of junctophilin-2. Thus, a sustained increase in calpain-2 may be detrimental to the heart.

To understand the geochemical characteristics of the No.9 coal in the Daheng Mine of the Ningwu coalfield, the trace element analysis was conducted through X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). The sedimentary environment was discussed according to the element geochemical parameters. The results show that Li, Ga, Hf, Zr, Nb, Th, and Ta are slightly enriched in the No. 9 coal of Daheng Mine. The average value of the rare earth elements and yttrium (∑REY) in coal here is 144.20 μg/g (excluding parting), which is higher than the average value of ∑REY in the world ’s coal and China ’s coal. The light rare earth elements (LREY) are enriched. The content of Eu was 0.12–2.10 μg/g with an average of 0.57 μg/g, and the Eu is obviously negatively abnormal. Most of the trace elements in the coal are positively correlated with the ash content, which shows that the occurrence of these trace elements is related to inorganic minerals. The results of sequential chemical extraction experiments show that rare earth elements mainly exist in coal in the form of aluminosilicate. The value of the Sr/Ba and the content of S reflect that the coal-forming environment was influenced by seawater. The values of V/Cr and Ni/Co reflect that the peat swamp is in an anaerobic environment and a strongly reducing environment during the coal-forming period.

In this paper, we demonstrated an artificial nanoparticles, Laponite, as a high performance rheological modifier in water-based drilling fluids. We made a comparison between Laponite nanoparticle and bentonite as rheological modifier in polyanionic cellulose (PAC) solution and weitghted water-based drilling fluids. In viscosity-shear rate test, both Laponite and bentonite could translate 0.5 wt.% PAC solution from Newton fluids to yield-pseudoplastic fluid. However, 1 wt.% Laponite was better in improving the shear-thinning behavior compared with 4 wt.% bentonite. In the stress-shear rate test, the results were fit with Bingham model with a high R2, and 1 wt.% Laponite/0.5 wt.% PAC suspension had a yield point of 5.19 Pa, which was higher than that of 4 wt.% bentonite/0.5 wt.% PAC suspension (3.13 Pa). Similarly, 1 wt.% Laponite/0.5 wt.% PAC suspension maintained a G’ of 12 Pa in the oscillation frequency sweep test, whereas G’ of 4%bentonite/0.5%PAC suspension was nearly 5 Pa. Particularly, 0.5 wt.% PAC /Laponite suspensions could maintain higher gel structure, yield point and better shear-thinning behaviors after 120°C hot rolling. The TEM image revealed that nanoscaled Laponite could form a “star network” with PAC in water, which explained the good rheological properties of PAC/LAP mixed suspensions. Besides, in the weighted drilling fluids, 1 wt.% Laponite could maintained a much higher gel strength compared with 4 wt.% bentonite.As the unique rheological properties, Laponite nanoparticles can greatly enhance abilities of water-based drilling fluids in circulating cuttings and making the borehole clean.

This paper presents the development of a new remediation technology of contaminated soil and groundwater using humic acid (HA) in permeable reactive barrier (PRB) for pipeline leakage. The objective of this study was to use humic acid that could be medium within a PRB to filter complex contaminated soil and groundwater containing chromium. Leakage of pollutants (such as hydrocarbon、gasoline、oil、wastewater、heavy metal et al) has a large economic and environmental impact. When a pipeline leak is large or undiscovered for a longer period of time, substantial volumes of gases and liquids can leak into the soil and groundwater, which can develop into dangerous situations involving costly remediation works. Traditional methods for remedying contaminated soil and groundwater from pipeline leakage, such as drilling and geochemical analysis, are destructive, time consuming and expensive. A PRB was determined to be the best option for remedying groundwater that has become contaminated with a wide range of organic contaminants (i.e., benzene, toluene, methylbenzene, xylene and polyaromatic hydrocarbons), heavy metals (i.e., lead and arsenic). PRB is installed in or down gradient from the flow path of a contaminant plume. The contaminants in the plume react with the media inside the barrier to either break the compound down into harmless products or immobilize contaminants by precipitation or sorption. It is made up of humic acid that reduce contaminants. With the development of industry and agriculture, environmental contamination has become more and more serious, especially heavy metal pollution, have been a major environmental issue, drawing much scientific and public attention. Chromium is identified as “priority pollutant” by the United States Environment Protection Agency (US EPA). the measurements show a significant increase of the adsorption of Cr (VI) because of the complexion reaction between HA and Cr (VI) occurred under acidic condition. It could be concluded that HA could be used effectively on remediation of Cr (VI)-contaminated soil and groundwater in a wide range of pH, with or without sunlight.

The watershed algorithm has been widely used in image segmentation for its characteristics of accurately positioning edge, simple operation and etc. But it also has drawbacks of easy to over-segmentation and loss important outline for the character of sensitive to noise. Aiming at the problem of over-segmentation of watershed algorithm, the paper brought out an improved image segmentation algorithm based on watershed, which can limit the number of existing regions that are allowed with combination pre-processing steps, so that the over-segmentation problem can be better solved. The result of experiment also verifies the correctness and feasibility of the proposed algorithm in the paper.

A fungal elicitor extracted fromAspergillus oryzae(Ahlb.) Cobn mycelia promoted the production of shikonin derivatives inOnosma paniculatumBur et Franch cell suspension cultures. Elicitor treatment also increased Ca2+concentration in RM9medium, which could be measured earlier than the elicited increase of shikonin formation. Several reagents known to induce Ca2+-influx and increase the intracellular-free Ca2+level, such as the addition of Ca (NO3)2·4H2O, the Ca2+ionophore A23187, and abscisic acid (ABA), appreciably suppressed the elicitor-promoted shikonin formation inOnosmacells. In contrast, the decrease of intracellular-free Ca2+level by the specific Ca2+-chelator ethylene glycol bis (β-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA) or the Ca2+—channel blocker, verapamil, enhanced the biosynthesis of shikonin even in the absence of elicitor. Treatment of cells with trifluoperazine (TFP) also stimulated shikonin formation inOnosmacell cultures. A rapid and transient drop of free Ca2+level in one protoplast was directly determined after the addition of elicitor toOnosmacell cultures. The inhibitory effect on shikonin formation by ABA was largely on account of its ability to restore the intracellular Ca2+level lowered by the elicitor. These results suggest that Ca2+play a significant role in an early stage of the elicitation process ofOnosmacells. The rapid drop of cytoplasmic Ca2+carries the elicitor signal and in turn regulates the biosynthesis of shikonin derivatives.