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Coal-dependent industries are the economic pillar of many countries; however, their contribution to air pollution also restricts long-term economic development. While the negative effects of environmental regulations on coal-dependent industries has attracted much attention, the health effects of such regulations remains barely quantitatively studied. Our study is based on a quasi-natural experiment created by a command-and-control policy in China’s cement industry, whereby cement enterprises are forced to stop production for a specific period of time every year. This paper adopted DID methods and found that direct pollution control measures for coal-dependent industries could significantly improve residents’ health levels and that the resultant reduction in medical expenditures could save 456.8 RMB yuan per capita per year. Additionally, our mechanism analysis found that the COPP is beneficial to residents’ health in that it reduces air pollution and sewage treatment rates. This means that pollution from coal-dependent industries has a large and underestimated impact on residents’ health. Environmental regulation of the coal-dependent industry could greatly improve the health of residents.

Background The extremely thermophilic bacterium Caldicellulosiruptor lactoaceticus can degrade and metabolize untreated lignocellulosic biomass containing xylan. The mechanism of the bacterium for degradation of insoluble xylan in untreated biomass has not been revealed. Results In the present study, the only annotated extracellular endo-β-1,4-xylanase (Xyn10B) with multidomain structures in C. lactoaceticus genome was biochemically characterized. Xyn10B contains three N-terminal consecutive family 22 carbohydrate-binding modules (CBMs), one GH10 catalytic domain (CD), two family 9 CBMs and two S-layer homology (SLH) modules in the C-terminal. CBM22a shares 27.1% and 27.2% sequence homology with CBM22b and CBM22c, respectively. The sequence homology between two CBM9 s and two SLHs is 26.8% and 25.6%, respectively. To elucidate the effect of multiple domains on the enzymatic properties of Xyn10B, the truncated variants of which (Xyn10B-TM1: CBM22a-CBM22b-CBM22c-CD10; Xyn10B-TM2: CBM22c-CD10; Xyn10B-TM3: CBM22c-CD10-CBM9a; and Xyn10B-TM4: CD10-CBM9a) were separately reconstructed, recombinantly expressed and biochemically characterized. Enzymatic properties studies showed that the optimal temperature for all four Xyn10B truncations was 65 °C. Compared to Xyn10B-TM3 and Xyn10B-TM4, Xyn10B-TM1 and Xyn10B-TM2 had higher hydrolytic activity, thermostability and affinity on insoluble substrates. It is noteworthy that Xyn10B-TM1 and Xyn10B-TM2 have higher enzymatic activity on insoluble xylan than the soluble counterparts, whereas Xyn10B-TM3 and Xyn10B-TM4 showed opposite characteristics. The kinetic parameters analysis of Xyn10B-TM1 on xylan showed V max was 5740, 1300, 1033, and 3925 U/μmol on insoluble oat spelt xylan (OSX), soluble beechwood xylan (BWX), soluble sugar cane xylan (SCX), and soluble corncob xylan (CCX), respectively. The results indicated that CBM22s especially CBM22c promoted the hydrolytic activity, thermostability and affinity on insoluble substrates of the Xyn10B truncations. The functions of CBM22, CBM9, CD and SLH are different, while contribute synergetically to the thermostability, protein structure integrity, substrate binding, and high hydrolytic activity on insoluble xylan of untreated lignocellulosic biomass. The domains of CBM22, CBM9, CD and SLH have different characteristics, which synergistically promote the thermostability, protein structure integrity, affinity on insoluble substrates and enzymatic activity properties of Xyn10B. Conclusions The extracellular endo-β-1,4-xylanase with multidomain structures of CBM, CD and SLH promote the biodegradation of insoluble xylan in untreated lignocellulosic biomass by thermophilic C. lactoaceticus.

The extreme thermophilic bacterium Caldicellulosiruptor kronotskyensis can use hemicelluloses and cellulose as carbohydrate source. The gene Calkro_0081 encoded a novel GH11 xylanase (Xyn11A) with a catalytic domain (GH-CD) and a carbohydrate binding module (CBM6). The native Xyn11A and two corresponded truncations Xyn11A-CD (catalytic domain of Xyn11A) and Xyn11A-CBM (carbohydrate binding module of Xyn11A) were respectively cloned, heterologously expressed, and biochemically characterized. The recombinant Xyn11A is active in a wide temperature range from 40 to 95 degrees C with the highest activity at 75 degrees C. Xyn11A was completely stable at 70 degrees C for 6 h and more than 50% activity was retained after incubation for 6 h at 75 degrees C. The optimum pH of Xyn11A was 6.0, and it retained 100% activity after 15 h incubation in pH 5.5-7.5 at 70 degrees C. As for Xyn11A-CD, the optimal pH value and temperature were 6.0 and 65 degrees C, the residual activity retained 30% after 6h at 60 degrees C. The respective specific activities of Xyn11A, Xyn11A-CD, and Xyn11A-CBM were 1752.0, 986.8, and 0 IU/mg on beechwood xylan (BWX) at optimum conditions. The activity of Xyn11A is the highest among the reported thermostable xylanases at 75 C. Using BWX as substrate, the final products were xylose and xylobiose after hydrolysis with Xyn11A or Xyn11A-CD. No hydrolytic activity of CBM6 was found, while which shows crucial functions on thermostability and activity for Xyn11A. The characteristics of thermostability and high activity make Xyn11A a potential enzyme for industry application. (C) 2014 Elsevier B.V. All rights reserved.

Cytidine-5'-diphosphocholine (citicoline or CDP-choline) is an essential endogenous intermediate in the biosynthesis of phosphatidylcholine. In the present study, primary dopaminergic cultures from mouse mesencephala were treated with citicoline to investigate its neuroprotective potential on the survival of dopaminergic neurons exposed to MPP(+) and glutamate. Treatment with citicoline alone significantly increased the survival of dopaminergic neurons compared to controls. MPP(+) or glutamate decreased the total number of dopaminergic neurons whereas citicoline afforded significant protection against either toxicity. Moreover, citicoline significantly decreased propidium iodide uptake by cultured cells. The study concludes that citicoline exerts stimulant and neuroprotective actions on cultured dopaminergic neurons.

Caldicellulosiruptor kronotskyensis grows on lignocellulosic biomass by the catalysis of intrinsic glycoside hydrolase and has potential application for consolidated bioprocessing. In current study, two predicted extra- (Xyn10A) and intracellular (Xyn10B) xylanase from C. kronotskyensis were comparatively characterized. Xyn10A and Xyn10B share GH10 catalytic domain with similarity of 41%, while the former contains two tandem N-terminus CBM22s. Xyn10A showed higher hydrolytic capability than Xyn10B on both beechwood xylan (BWX) and oat spelt xylan (OSX). Truncation mutation experiments revealed the importance of CBMs for hydrolytic activity, substrate binding and thermostability of Xyn10A.While the quantity of CBM was not directly related to bind and thermostability. Although CBM was considered to be crucial for substrate binding, Xyn10B and Xyn10A as well as truncations performed similar binding affinity to insoluble substrate OSX. Analysis of point mutation revealed similar key residues, Glu493, Glu601 and Trp658 for Xyn10A and Glu139, Glu247 and Trp305 for Xyn10B. Both Xyn10A and Xyn10B exhibited hydrolytic activity on the mechanical pretreated corncob. After pre-digested by Xyn10A or Xyn10B, the micropores inthe the mechanical pretreated corncob were observed, which enhanced the accessibility for cellulase. Compared with corncob hydrolyzed with cellulase alone, enhanced hydrolytic performance of was observed after pre-digestion by Xyn10A or Xyn10B.

Network torn is a key method in analog circuit fault diagnose. Generally, all torn terminals must be mensurability in implementing network tearing. In accordance with the restrictions, presentsing partition conditions of solvable subnet those partial torn terminals inaccessible, this paper analyze mensurability of subnet to lay the groundwork of further fault location.

The xylanolytic extremely thermophilic bacterium Caldicellulosiruptor owensensis provides a promising platform for xylan utilization. In the present study, two novel xylanolytic enzymes, GH10 endo-beta-1,4-xylanase (Coxyn A) and GH39 beta-1,4-xylosidase (Coxyl A) encoded in one gene cluster of C. owensensis were heterogeneously expressed and biochemically characterized. The optimum temperature of the two xylanlytic enzymes was 75 degrees C, and the respective optimum pH for Coxyn A and Coxyl A was 7.0 and 5.0. The difference of Coxyn A and Coxyl A in solution was existing as monomer and homodimer respectively, it was also observed in predicted secondary structure. Under optimum condition, the catalytic efficiency (k(cat)/K-m) of Coxyn A was 366 mg ml(-1) s(-1) on beechwood xylan, and the catalytic efficiency (k(cat)/K-m) of Coxyl A was 2253 mM(-1) s(-1) on pNP-beta-D-xylopyranoside. Coxyn A degraded xylan to oligosaccharides, which were converted to monomer by Coxyl A. The two intracellular enzymes might be responsible for xylooligosaccharides utilization in C. owensensis, also provide a potential way for xylan degradation in vitro.