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Charge distribution on every atom of carbon matter in four dimension forms (cluster, fullerene, atomistic carbon chain, nanotube, graphene, surface and solid) was investigated by the first-principles calculation. It is found that the charge distribution in most of these materials is inhomogeneous, even in one certain solid phase. We found that if one atom in carbon has different surrounding environment from another one nearby, they always have electron transfer, that is, they have different charge. In round C10 ring, C24 and C60 fullerenes, charge is zero, while charge is not zero in pentagon C10 ring, C30 and C70 fullerenes. At the ends of atomistic chains, nanotube or on the edges of graphenes, carbon atoms have larger positive or negative charge, while almost zero in the central parts. Charge is zero in diamond and graphite, while it is not zero in the high pressure solid phase hexagonite or on some carbon surfaces. The non-zero charge in carbon possibly means its non-zero valence.

MiR-199 expression is associated with liver cancer. Bioinformatics analysis revealed that miR-199 has a complementary binding site to the 3'-UTR region of Snail mRNA. This study investigated whether miR-199 plays a role in regulating Snail expression and affecting epithelial-mesenchymal transition (EMT) and invasion of hepatoma cells.The Dual-Luciferase reporter gene assay validated the targeted regulation between miR-199 and Snail. QRT-PCR was used to detect and compare the expression of miR-199 and Snail mRNA in human normal liver HL7702 cells, low metastatic MHCC97L cells, and high metastatic MHCC97H cells. MHCC97H cells were cultured in vitro and divided into two groups: miR-NC group and the miR-199 mimic group followed by the analysis of the expression of Snail, E-cadherin, and N-cadherin, as well as cell invasion ability by transwell assay.There was a targeted regulatory relationship between miR-199 and Snail mRNA. Compared with HL7702 cells, miR-199 expression was significantly decreased, and Snail expression was significantly increased in MHCC97L and MHCC97H cells, with more changes being observed in high metastatic MHCC97H cells. The transfection of miR-199 mimic significantly downregulated the expression of Snail and N-cadherin in MHCC97H cells, increased E-cadherin expression, inhibited the cell's EMT process, and invasion.The decrease of miR-199 expression plays a role in upregulating the expression of Snail and promoting EMT and invasion of hepatocarcinoma cells. The increase of the expression of miR-199 can inhibit the expression of Snail and inhibit the EMT process and invasion ability of hepatoma cells.

An ultra-thin waterborne acoustic metamaterial (AM), which is made of steel and composed of multi-Helmholtz resonators (MHRs), is proposed to achieve perfect sound absorption at low frequencies, which are generated around the resonance mode. The average surface acoustic impedance of the metamaterial is almost perfectly matched with water impedance under the action of resonance among the HRs, thus the perfect sound absorption is achieved. The case of two resonators is taken as an example to verify the design idea. By adjusting HRs’ sizes in simulation, the sound absorption coefficient reaches 99.6% at low frequency of 2740 Hz with ultra-thin thickness less than [Formula: see text]. The abnormal physical properties of AMs are often accompanied by abnormal effective material parameters, which turn to be negative near the perfect sound absorption through inversion calculation. The HRs proposed are simple to fabricate, mechanically stable, and convenient to couple with other resonators to achieve low-frequency broadband sound absorption.

Pheromone-binding proteins (PBPs) are distributed widely on the antennae of insects, and they are believed to be involved in the process of chemical signal transduction, but their interaction with chemicals is largely unknown. Here, we present our findings on the key amino acid residues of PBPs in the gypsy moth, Lymantria dispar. Potential key residues were screened with the Calculate Mutation Energy program and molecular docking methods. Mutated proteins were obtained by mutating residues to alanine via site-directed mutagenesis. Circular dichroism (CD) spectroscopy showed that the mutated proteins formed α-helix, and the stability of protein structure was influenced due to mutations. Fluorescence binding assays were further conducted with the mutated proteins, sex pheromones and analogues. Results showed that to PBP 1, tyrosine at position 41 and phenylalanine at position 76 could be the key amino acid residues influencing the stability of structure; in addition, phenylalanine at 36 and lysine at position 94 could be key amino acid residues interacting with chemicals. To PBP 2, glycine at position 49, phenylalanine at position 76 and lysine at position 121 could be the key amino acid residues in the structural stability. These results shed light on the relationship between the specific amino acids and functions of PBPs in transmitting the chemical signals.

In view of the current policy design, which is created to influence the growth of the renewable energy sector, the status quo of different subjects’ role orientation and behaviour mechanism is neglected. This paper constructs the evolutionary game model of the three parties in the renewable energy industry involved: government, enterprise and consumer. The results show that the initial stage of government incentive policies should increase subsidies to enterprises and increase price incentives for consumers. At the same time, enterprises must actively respond to the call of the state. With the further advancement of the policy, the government should reduce subsidies to enterprises appropriately, and urge enterprises to develop production technologies for renewable energy vigorously to reduce the operation of enterprises’ cost. The results can provide theoretical reference and realistic support for the government.

© 2016, Copyright © Taylor & Francis Group, LLC. Shape memory alloys (SMAs) in the form of rings or tubes with two-way shape memory effect (TWSME) have been applied to high-speed precision micro-mechanical systems. This study investigates the development of NiTi alloy rings with TWSME and analyzes the effects of annealing and thermo-mechanical treatments. The results show there is a maximum in TWSME with respect to annealing temperature, loading deformation, training temperature, and cycle, respectively. The TWSME of SMA rings stabilizes earlier than structure dimension during training. The annealing and training change phase transition temperatures, which has a negative effect on the SMA ring with application to clamping device. A prototype ring made of Ni-49.2 at%Ti was developed and applied to a high-seed precision micro-spindle. Its performance under static and ultra-high speed rotation conditions was tested. The results show the ring developed in this study satisfies the operation and clamping requirements of high-speed precision micro-mechanical systems.

Summary Arceuthobium sichuanense is a hemiparasitic angiosperm that infects Qinghai spruce (Picea crassifolia Kom.) in Qinghai province, China, and causes severe damage to spruce forests in Qinghai-Tibet Plateau. In this study, the impact of A. sichuanense infection on mature and young trees of Qinghai spruce was evaluated by examining needle and current-year shoot morphology, needle water and nitrogen-use efficiency (NUE) and needle nitrogen concentration. The most apparent effect of A. sichuanense infection was a significant reduction in both needle size distal to infection and current-year shoot length in the infected branches (p

A number of nonlinear microbial models of soil carbon decomposition have been developed. Some of them have been applied globally but have yet to be shown to realistically represent soil carbon dynamics in the field. Therefore a thorough analysis of their key differences will be very useful for the future development of these models. Here we compare two nonlinear microbial models of soil carbon decomposition: one is based on reverse Michaelis-Menten kinetics (model A) and the other on regular Michaelis-Menten kinetics (model B). Using a combination of analytic solutions and numerical simulations, we find that the oscillatory responses of carbon pools model A to a small perturbation in the initial pool sizes have a higher frequency and damps faster than model B. In response to soil warming, soil carbon always decreases in model A; but likely decreases in cool regions and increases in warm regions in model B. Maximum CO2 efflux from soil carbon decomposition (Fmax) after an increased carbon addition decreases with an increase in soil temperature in both models, and the sensitivity of Fmax to the amount of carbon input increases with soil temperature in model A; but decreases monotonically with an increase in soil temperature in model B. These differences in the responses to soil warming and carbon input between the two nonlinear models can be used to differentiate which model is more realistic with field or laboratory experiments. This will lead to a better understanding of the significance of soil microbial processes in the responses of soil carbon to future climate change at regional or global scales.

A patient had right upper quadrant pain with sclera was transferred from emergency room to the hospital, she was proposed to have acute cholecystitis, gallstones, obstructive jaundice, and a four-year history of gallbladder stones. The NMR results showed that the gallbladder was significantly enlarged and the gallbladder wall was thickening irregularly. The liver morphology was not abnormal except with extensive intrahepatic bile duct dilatation. The MRCP results demonstrated that the intrahepatic bile ducts were significant expanded. The ERCP results showed that duodenal stenosis and extra-hepatic bile duct stenosis. We placed a plastic stent of 8.5Fr and 12 cm in length in the hepatic duct, and after biliary plastic stent placement, jaundice was rapidly reduced and liver function was improved significantly. A surgery was performed and the final pathologic diagnosis is a complication of Xanthogranulomatous cholecystitis with Mirizzi syndrome. After the surgery of cholecystectomy and a bile duct repair were performed, the patient was recovered well. Conclusively, if a patient was diagnosed as biliary stricture, a biliary metal stent should not be placed until pathological diagnosis of malignancy.

Summary Previous risk prediction studies have mostly shown that suitable areas for pine wood nematode, Bursaphelenchus xylophilus (PWN), in China are mainly concentrated in eastern and southern China, with pest reaching no further northern than the Yangtze River basin. The Chinese pine (Pinus tabuliformis, Chinese pine or Chinese red pine) is the main, native, afforestation species in areas to the north of the Yangtze River basin. To our knowledge, there is no report on PWN infecting Chinese pines in the north of the Yangtze. In this study, we used Baermann funnel method and several PCR primers to detect the presence of PWN in Chinese pine forest fields in 2010 in Shaanxi, China, which is far to the north of the Yangtze River and a cause for concern. Pinus koraiensis (Korean pine) may also be at risk and should also be monitored to prevent invasion by PWN.

Land models, which have been developed by the modeling community in the past two decades to predict future states of ecosystems and climate, have to be critically evaluated for their performance skills of simulating ecosystem responses and feedback to climate change. Benchmarking is an emerging procedure to measure and evaluate performance of models against a set of defined standards. This paper proposes a benchmarking framework for evaluation of land models. The framework includes (1) targeted aspects of model performance to be evaluated; (2) a set of benchmarks as defined references to test model performance; (3) metrics to measure and compare performance skills among models so as to identify model strengths and deficiencies; and (4) model improvement. Component 4 may or may not be involved in a benchmark analysis but is an ultimate goal of general modeling research. Land models are required to simulate exchange of water, energy, carbon and sometimes other trace gases between the atmosphere and the land-surface, and should be evaluated for their simulations of biophysical processes, biogeochemical cycles, and vegetation dynamics across timescales in response to both weather and climate change. Benchmarks that are used to evaluate models generally consist of direct observations, data-model products, and data-derived patterns and relationships. Metrics of measuring mismatches between models and benchmarks may include (1) a priori thresholds of acceptable model performance and (2) a scoring system to combine data-model mismatches for various processes at different temporal and spatial scales. The benchmark analyses should identify clues of weak model performance for future improvement. Iterations between model evaluation and improvement via benchmarking shall demonstrate progress of land modeling and help establish confidence in land models for their predictions of future states of ecosystems and climate.

Immunoregulatory function of peripheral blood monocytes was studied in 20 patients with colorectal cancer, by assaying interleukin 1 (IL-1) and prostaglandin E2 (PGE2) in the culture supernatant of lipopolysaccharide-stimulated monocytes. The results showed that IL-1 activity of the monocyte culture supernatant was decreased in the preoperative patients, compared with that of controls or postoperative groups; the PGE2 content of the culture supernatant of monocytes from the preoperative cases was increased, compared to normal controls or to the postoperative groups. Again, we found that there was significant negative correlation between IL-1 activity and the PGE2 content, with the activity of IL-1 the lowest and the content of PGE2 the highest in advanced colonic cancer patients.

Tomato yellow leaf curl China virus, associated with a satellite DNA β, has been detected in Datura stramonium (jimsonweed) with leaf curl disease for the first time in China.