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The compression behavior of polytetrafluoroethylene (PTFE)–aluminum (Al) is studied by the means of the two-dimensional finite element analysis of mesoscale model containing a random dispersion of particles. The results show that for composite materials with a single particle size the strength of the material increases first and then decreases with the increase of the content of metal particles. When the particle content is high the strength of the material can be improved by a reasonable particle gradation. The influence of particle content and size on the strength of particle composites is obtained and theoretical analysis is carried out from the perspective of the formation and evolution of force chains.

In the reliability designing procedure of the vehicle components, when the distribution styles of the random variables are unknown or non-normal distribution, the result evaluated contains great error or even is wrong if the reliability value R is larger than 1 by using the existent method, in which case the formula is necessary to be revised. This is obviously inconvenient for programming. Combining reliability-based optimization theory, robust designing method and reliability based sensitivity analysis, a new method for reliability robust designing is proposed. Therefore the influence level of the designing parameters’ changing to the reliability of vehicle components can be obtained. The reliability sensitivity with respect to design parameters is viewed as a sub-objective function in the multi-objective optimization problem satisfying reliability constraints. Given the first four moments of basic random variables, a fourth-moment technique and the proposed optimization procedure can obtain reliability-based robust design of automobile components with non-normal distribution parameters accurately and quickly. By using the proposed method, the distribution style of the random parameters is relaxed. Therefore it is much closer to the actual reliability problems. The numerical examples indicate the following: (1) The reliability value obtained by the robust method proposed increases (>0.04%) comparing to the value obtained by the ordinary optimization algorithm; (2) The absolute value of reliability-based sensitivity decreases (>0.01%), and the robustness of the products’ quality is improved accordingly. Utilizing the reliability-based optimization and robust design method in the reliability designing procedure reduces the manufacture cost and provides the theoretical basis for the reliability and robust design of the vehicle components.

An initial turntable calibration method based on coordinate transformation was proposed to improve the target tracking precision of a vehicle-borne tracking system.First,according to the coordinate transformation theory,a precise turntable calibration model was established and a transformation matrix for the turntable calibration was obtained.Then,an approximate calibration approach based on the practical need was derived with reasonable analysis and careful approximation.Finally,a combined calibration method by using both approximate calibration and precise calibration was implemented in the turntable initial calibration process for a practical vehicle-borne opto-electronic tracking system.Experimental results show that the combined calibration method can improve the efficiency of turntable initial calibration.After precise calibration,the tracking error of the turntable is smaller than 0.1° for a remote target larger than 10 km away,which completely satisfies the precision requirements of the vehicle-borne opto-electronic tracking system.This calibration method has been successfully used in several vehicle-borne opto-electronic tracking systems.

The aim of this work is to utilize the microbial fuel cell for removing metals and sulfate from acid mine drainage using sewage sludge organics and simultaneous electricity generation. The enriched sulfate-reducing mixed culture was used as the cathodic biofilm and the sludge as the substrate. Under anaerobic conditions, 71.2% sulfate, 99.7% heavy metals, and 51.6% total chemical oxygen demand are removed at an electrode spacing of 4 cm and a sludge concentration of 30% (v/v) after 10-day treatment. A maximum power density of 51.3 mW/m2 is obtained. Approximately 79.5% of the dissipated sulfate is converted to element sulfur or polysulfides. The sulfide concentration is kept at below 20 mg-S/L. The concentrations of heavy metals are in the range of 0.02–0.06 mg/L in the effluent, which are far below the levels required by Chinese legislation. Microbial community analysis reveals that sulfate-reducing bacteria in Desulfuromonadales are dominant on the cathodic biofilm at the end of experiments. Thi...

From multi-substituted 8-aminoimidazo[1,2-a]pyrazines, prepared via modified Groebke–Blackburn–Bienayme reaction, a Pd-catalyzed cyclization reaction was discovered, leading to a rare (Z)-4,5-dihydro-3H-[1,3]diazocine system. Conditions of this cyclization were screened and DMF solvent was found as one of the key factors for the cyclization.

Menin is an essential oncogenic cofactor for mixed lineage leukemia (MLL)-mediated leukemogenesis, functioning through its direct interaction with MLL1 protein. Therefore, targeting the menin–MLL1 protein–protein interface represents a promising strategy to block MLL-mediated leukemogenesis. On the basis of co-crystal structure analysis, starting from thienopyrimidine chemotype, we have investigated the detailed structure–activity relationship of the piperazinyl-dihydrothiazole moiety. Several compounds were found with potent inhibitory activity against menin and better activities in cell-based experiments than MI-2-2. Molecular docking analysis revealed a less explored subpocket, which could be used for the design of new menin–MLL1 inhibitors.

Pseudomonas aeruginosa employs its type VI secretion system (T6SS) as a highly effective and tightly regulated weapon to deliver toxic molecules to target cells. T6SS-secreted proteins of P. aeruginosa can be detected in the sputum of cystic fibrosis (CF) patients, who typically present a chronic and polymicrobial lung infection. However, the mechanism of T6SS activation in the CF lung is not fully understood. Here we demonstrate that extracellular DNA (eDNA), abundant within the CF airways, stimulates the dynamics of the H1-T6SS cluster apparatus in Pseudomonas aeruginosa PAO1. Addition of Mg 2+ or DNase with eDNA abolished such activation, while treatment with EDTA mimicked the eDNA effect, suggesting that the eDNA-mediated effect is due to chelation of outer membrane-bound cations. DNA-activated H1-T6SS enables P. aeruginosa to nonselectively attack neighboring species regardless of whether or not it was provoked. Because of the importance of the T6SS in interspecies interactions and the prevalence of eDNA in the environments that P. aeruginosa inhabits, our report reveals an important adaptation strategy that likely contributes to the competitive fitness of P. aeruginosa in polymicrobial communities.

A porous MOF constructed from a [Cu2(COO)4] secondary building unit, H3L (H3L = [1,1';3',1'']terphenyl-4,5',4''-tricarboxylic acid), and pyrazine ligands features a unique hendecahedron cage-like cavity with good stability and a high BET surface area of 3235 m(2) g(-1), showing good controlled drug release property of ibuprofen over those of anethole and guaiacol.

TiO 2 thin films doped with neodymium(Nd) in the range from 0 at.% to 10at. % were prepared on glass substrates by sol-gel dip-coating method. Water contact angle on the Nd-doped TiO 2 films were measured by contact angle analyzer. The water contact angle measurement result showed that the hydrophily of the films improved when the Nd 3+ concentration increased to 5 at.%. The photocatalytic activity of the undoped and Nd-doped TiO 2 thin films were investigated by the degradation of methylene blue under high-voltage mercury lamp. The results showed that 5 at.% Nd-doped TiO 2 thin film exhibited the highest photocatalytic efficiency.

A synchronization algorithm that applies to the Code Division Multiplexing (CDM) link based on Walsh Code is proposed to solve problems of pre-existing algorithms based on pilot. The algorithm proposed by this paper achieved blind synchronization without pilot, and improved applicability at low SNR by incoherent accumulation. The simulation results indicate that the proposed algorithm achieves high synchronization precision and acceptable synchronization time, and can thus be applied to CDM links based on Walsh Codes of GBBF (Ground Based Beam forming).

A gear’s finite-element model has been set up according to the parameter functions of the involute and tooth root curve, single and double tooth meshing region have been obtained according to the results of contact analysis. A tooth root’s bending stress has been calculated when meshing in the ultimate position in single tooth meshing region, and this stress has been contrasted with the results of a classical method as the maximum of a circle. The results of theoretical method were far away from that of finite-element calculation before being modified and were a little larger than the later after being modified. Reasons leading to this difference have been analyzed.

To improve the reliability effectively, the reliability sensitivity method is researched with considering that a mechanical system or component may fail in many modes, which is simplified to be a series system model. It is supposed that all ultimate state functions in multi-failure modes are normal distribution. A computation module for total reliability is established. A kind of computation method for reliability sensitivity in multi-failure modes is built based on that in single failure mode. A pin connection component that may fail in shear fracture, bruise on pin or hole surfaces, or in any assemble with two different modes is computed, and the reliability and sensitivity of the component are estimated. Consequently, it is found that the most effective method to enhance the reliability was to enhance the crushing strength of the pin.

Vibration characteristic of direct drive A/C bi-rotary milling head is been analyzed by finite element method (FEM), former four order vibration modes of the milling’s structure are given. The influence of the swing angle of the A-axis to the natural frequency of the milling head is analyzed. The natural frequencies when the milling head is working are interval values, the first order natural frequency is [120.48, 122.91], the second order natural frequency is [139.68, 142.08], the third order natural frequency is [328.68, 331.9], the fourth order natural frequency is [369.68, 372.45]. This computing provides technological support for design and improvement of this type of milling head.

Utilizing finite element software, an universal program has been worked out by the APDL, and it can output the heat dissipating capacity of appointed surfaces in analysis software. The program is so powerful that it can calculate the heat dissipating capacity of heat conductor in which the heat transfer two-dimensionally or three-dimensionally even if the heat conductor is anisotropic, which is difficult to calculate with the mathematic analysis method. The method mentioned in the paper can diminish the inaccuracy caused by the predigestion with the mathematic analysis method. The calculation principle of the program was introduced in detail. Comparing the result of the program with that got by mathematic method, it was indicated that the calculation error of program is very small.

The dynamic performance of numerical control (NC) machine is not only basis of evaluation for the vibration resistance and stability, but also theory basis of optimizing dynamic performance, and improving processed quality. As digital design method, visual design realizes "visibility" during the whole design process, increases design efficiency and guarantees the quality, which make visual design preferred design method in large mechanical engineering. In this paper, the analysis of dynamic performance on NC machine and visual design method will be integrated, taking a NC machining center built by Shenyang machine tool group as a study case, the dynamic visual design flow to be proposed, including the design purpose, content and design methods, finally, the dynamic performance of visual simulation we have done, taking the strength, inherent characteristics and harmonic response into account, offers the foundation about structural performance optimization on the machine.

This paper presents a method for tolerance design of four-bar function generating mechanisms with joint clearances using Taguchi method. Based on previous studies made by other researchers, we propose a model to quantify the effects of uncertain factors on the accuracy of four-bar function generating mechanisms. Taguchi’s approach is applied to select the optimal tolerance ranges for the design parameters of function generation mechanisms. Sensitivity maps are plotted to provide an insight to the effects of parameter errors on the performance variances of four-bar function generating mechanisms. To illustrate the efficiency of the proposed methodology, the tolerance design of a four-bar function generator with joint clearances is discussed.

e18802Background: Patient characteristics, perceptions and experience concerning cancer clinical trials (CCT) may affect study accrual and quality. Our study aimed to evaluate 1) subjects’ percepti...

Two kinds of MAX RES CUT problems, the MAX s−t CUT and the MAX s−t−v CUT, with limited unbalanced constraints are considered. Approximation algorithms used in Frieze and Jerrum (Integer Programming and Combinatorial Optimization, vol. 920, pp. 1–13, Springer, Berlin, 1995), Galbiati and Maffioli (Theor. Comput. Sci. 385:78–87, 2007), Han et al. (Math. Program. Ser. B 92:509–535, 2002) and Ye (Math. Programm. 90:101–111, 2001) are extended to the two MAX RES CUT problems. A special matrix P is constructed by which it can ensure that the given nodes s,t are feasible to equality constraints with probability one for the MAX s−t CUT and s,t,v are feasible to equality constraints with at least probability 0.912 for the MAX s−t−v CUT. A fussy greedy sizing-adjusted procedure is then proposed to confirm that the round solution is feasible for all constraints. We find these extensions are nontrivial and some interesting results about performance ratio are obtained for the MAX RES CUT problem with limited unbalanced constraints.

Variable neighborhood search (VNS) metaheuristic as presented in Festa et al. [Randomized heuristics for the MAX-CUT problem, Optim. Methods Software 17 (2002) 1033–1058] can obtain high quality solution for max-cut problems. Therefore, it is worthwhile that VNS metaheuristic is extended to solve max-bisection problems. Unfortunately, comparing with max-cut problems, max-bisection problems have more complicated feasible region via the linear constraint eTx=0. It is hard to directly apply the typical VNS metaheuristic to deal with max-bisection problems. In this paper, we skillfully combine the constraint eTx=0 with the objective function, obtain a new optimization problem which is equivalent to the max-bisection problem, and then adopt a distinct greedy local search technique to the resulted problem. A modified VNS metaheuristic based on the greedy local search technique is applied to solve max-bisection problems. Numerical results indicate that the proposed method is efficient and can obtain high equality solution for max-bisection problems.

A global view of power system's frequency behavior opens up a new window for analyzing system's dynamics. With the aid of global positioning system, measurements from different locations would have synchronous time; therefore a system-wide observation and analysis would be possible. As part of the US-wide power frequency monitoring network project this paper focus on simulation study results of power frequency dynamics of the Eastern U.S. system. The study assesses the frequency measurement accuracy needed to observe frequency dynamics from events such as remote generation drops. Electromechanical-wave propagation phenomena during system disturbances have been observed. The speeds of electromechanical-wave propagation in different areas of the U.S. systems were estimated and their characteristics were discussed.

Pseudomonas aeruginosa is an important pathogen commonly isolated from patients with burns, wounds and cystic fibrosis (Lyczak et al., 2000; Gellatly and Hancock, 2013). The P. aeruginosa strain PAO1 was originally reported as a wound isolate from a patient in Australia in 1955 (Holloway, 1955), and has since been studied in many laboratories as a reference strain (Stover et al., 2000). However, a number of genetic variants of PAO1 in different laboratories have been reported including a large 2.2 Mb inversion and a number of single nucleotide variants and insertion-deletion mutations (Stover et al., 2000; Heurlier et al., 2005; Klockgether et al., 2010).

The reformation of curriculum system and course content is one of keys to meet “a Plan for educating and training outstanding engineering” (PETOE) in Chinese higher-education. It is also a challenge that the Chinese higher-education should face to achieve the goal of PETOE, this paper analyzed the nature and connotation of PETOE in Chinese higher-education, and introduced the reformation of the civil engineering in Huaiyin Institute of Technology (HYIT) from the curriculum system to course contents to implement the PETOE in HYIT, it also studied the curriculum structure ought to execute in the curriculum system. Lastly, it discussed the integration and reconfiguration for curriculum system of PETOE to guarantee the successful implementation of the PETOE in civil engineering

Using a 2,3-diamino pyrazine substrate and yttrium triflate catalyst, various 2-alkyl and aryl substituted 3,8-diaminoimidazo[1,2-a]pyrazines were efficiently prepared through Groebke-Blackburn-Bienayme MCR. In particular, a novel 2-piperonyl 3,8-diaminoimidazo[1,2-a]pyrazine structure was prepared exclusively with this new method and was found to have moderate Hsp90 inhibitory activity. A crystalline complex with N-terminus ATP domain of Hsp90 and one of the new Hsp90 inhibitors was also obtained to elucidate the origin of activity of 2-piperonyl 3,8-diaminoimidazo[1,2-a]pyrazines.

Past research suggests that spiritual leadership plays a pivotal role in enhancing employee job performance, yet we have little understanding of how and when spiritual leadership enhances employee ...

BackgroundThe bacterial genus Salmonella contains thousands of serotypes that infect humans or other hosts, causing mild gastroenteritis to potentially fatal systemic infections in humans. Pathogenically distinct Salmonella serotypes have been classified as individual species or as serological variants of merely one or two species, causing considerable confusion in both research and clinical settings. This situation reflects a long unanswered question regarding whether the Salmonella serotypes exist as discrete genetic clusters (natural species) of organisms or as phenotypic (e.g. pathogenic) variants of a single (or two) natural species with a continuous spectrum of genetic divergence among them. Our recent work, based on genomic sequence divergence analysis, has demonstrated that genetic boundaries exist among Salmonella serotypes, circumscribing them into clear-cut genetic clusters of bacteria.Methodologies/principal findingsTo further test the genetic boundary concept for delineating Salmonella into clearly defined natural lineages (e.g., species), we sampled a small subset of conserved genomic DNA sequences, i.e., the endonuclease cleavage sites that contain the highly conserved CTAG sequence such as TCTAGA for XbaI. We found that the CTAG-containing cleavage sequence profiles could be used to resolve the genetic boundaries as reliably and efficiently as whole genome sequence comparisons but with enormously reduced requirements for time and resources.ConclusionsProfiling of CTAG sequence subsets reflects genetic boundaries among Salmonella lineages and can delineate these bacteria into discrete natural clusters.

Recently, active portfolio management problems are paid close attention by many researchers due to the explosion of fund industries. We consider a numerical study of a robust active portfolio selection model with downside risk and multiple weights constraints in this paper. We compare the numerical performance of solutions with the classical mean-variance tracking error model and the naive1/Nportfolio strategy by real market data from China market and other markets. We find from the numerical results that the tested active models are more attractive and robust than the compared models.

This paper discusses the impact of non-tradable share reform on the volatility and efficiency of market. The rich empirical studies based on EGARCH(1,1)-M model and the data of CSRC(China Securities Regulatory Commission) industry indexes (including 13 industry indexes) are done and the empirical results show that, the reform of non-tradable share increases the short term volatility and it reduces the long term volatility of market. Especially, for some industries, such as, Commercial trade industry, Manufacturing industry and Social services, the short term volatility raised by the reform of non-tradable share is the maximum, while is the minimum in the Financial services industry, Culture industry and Public utility. In addition, after the reform of non-tradable share, the impact of new information on the market is weakening for most nonpublic service industries, while the impact is strengthening and significant for Public utility, Mining industry, Delivery warehousing and Social services. Index Terms Non-tradable shares reform, EGARCH model, Volatility, Market efficiency.

An EMTP-based arc furnace model was developed for evaluation of flicker concerns associated with supplying a large integrated steel mill as they go from one to two furnace operation and as system changes are implemented that will affect the short circuit capacity at the 230 kV power supply substation. The model includes a dynamic arc representation which is designed to be characteristic of the initial portions of the melt cycle when the arc characteristics are the most variable (worst flicker conditions). The flicker calculations are verified using previous measurements with one furnace operation. Flicker simulations were then performed to evaluate a variety of different possible system strengths with both one and two furnaces in operation. The primary flicker measure used for this study is the unweighted RMS value of the fluctuation envelope, expressed as a percentage of the RMS line-to-ground voltage magnitude.

Background The use of biomarkers for selecting non-small cell lung cancer (NSCLC) patients for treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is essential. The aim of this study was to explore whether biomarkers detected in plasma were predictive for response to EGFR-TKIs and survival time of NSCLC patients. Methods Tumor tissues and paired blood were collected from 134 advanced NSCLC patients treated with EGFR-TKIs. EGFR mutations in both types of specimens, and expression of transforming growth factor-alpha and beta one (TGF-α and TGF-β1) were assessed in NSCLC patients. Concentrations of circulating free DNA were detected in plasma from both NSCLC patients and healthy subjects. The clinical significance of EGFR mutations, levels of cytokines, and circulating free DNA was assessed in advanced NSCLC patients. Results EGFR mutations were detected in 68 tumor samples and 17 plasma samples of 134 NSCLC patients. The concentrations of circulating free DNA were higher in NSCLC patients than in healthy subjects. Patients with high TGF-β1 level showed shorter overall survival and worse response to EGFR-TKIs than patients with low TGF-β1 level. Conclusions Plasma levels of TGF-β1 may be a marker for predicting response to EGFR-TKIs and survival time in NSCLC patients.

The deadly human typhoid agent was initially classified as a species called Salmonella typhi but later reclassified as a serovar of Salmonella enterica together with other pathogenically diverse serovars. The dynamic changes of Salmonella taxonomy reflect the need to clarify the phylogenetic status of the Salmonella serovars: are they discrete lineages or variants of a genetic lineage? To answer this question, we compared S. typhi and other Salmonella serotypes. We found that the S. typhi and Salmonella typhimurium strains had over 90% and ca. 80%, respectively, of their genes identical; however, between S. typhi and S. typhimurium, this percentage dropped to 6%, suggesting the existence of genetic boundaries between them. We conclude that S. typhi and the other compared Salmonella serovars have developed into distinct lineages circumscribed by the genetic boundary. This concept and methods may be used to delineate other Salmonella serotypes, many of which are polyphyletic, needing differentiation.

DT104 emerged as a new branch of Salmonella typhimurium with resistance to multiple antimicrobials. To reveal some general genomic features of DT104 for clues of evolutionary events possibly associated with the emergence of this relatively new type of this pathogen, we mapped 11 independent DT104 strains and compared them with non-DT104 S. typhimurium strains. We found that all 11 DT104 strains contained three insertions absent in non-DT104 strains, i.e., the previously reported ST104, ST104B and ST64B. However, SGI-1, a genomic island known to be responsible for DT104 multidrug resistance, was not present in all DT104 strains examined in this study: one DT104 strain did not contain SGI-1 but carried a 144 kb plasmid, suggesting possible evolutionary relationships between the two DNA elements in the development of antimicrobial resistance.

Compact fluorescent lamps (CFLs) have the potential to increase the overall harmonic distortion levels on distribution systems. Measurements of the harmonic characteristics of different types of CFLs are presented and the possible impacts on a distribution system are analyzed. The analysis uses a combination of EMTP simulations and conventional harmonic analysis simulations to predict the distribution system distortion levels as a function of system characteristics, the CFL characteristics, and the CFL penetration level.

Elicitation is an important strategy to improve production of secondary metabolites in vitro. Artemisinic acid was studied as a novel elicitor to enhance the yield of terpenoid indole alkaloids in the present paper. Our results demonstrated that the concentrations of vindoline and vinblastine were increased by sixfold and twofold, respectively, compared to those of the control group after treatment with artemisinic acid. To elucidate the underlying mechanism, we investigated the gene expression of four enzymes involved in the biosynthetic pathway of vinblastine in the suspension-cultured cells of Catharanthu sroseus. RT-PCR experiment showed that artemisinic acid was able to up-regulate the transcriptions of tryptophan decarboxylase, geraniol 10-hydroxylase, tabersonine 16-hydroxylase and deacetoxyvindoline 4-hydroxylase.

On the basis of the physical model of linear double inversed pendulum, firstly, this paper establishes nonlinear model of it with SimMechanics toolbox of Matlab, and combined with LQR optimal control method based on kalman filter to design the controller and state observer, finally, inhibit existing system noises and observation noises effectively, In addition, it realizes stability control of the linear double inversed pendulum.

The system configuration, theory of operation, computer simulations, and important application experiences of a (750 kVA) superconducting magnetic device (Micro-SMES) for application on power distribution circuits to enhance customer power quality are presented. The functions of the major components of the Micro-SMES are separately discussed and the operation of each component is illustrated with an Electro-Magnetic Transients Program (EMTP) simulation example. Application performance characteristics obtained from the first practical installation of a Micro-SMES are summarized and its protection effectiveness is evaluated. >

A key issue troubling bacterial taxonomy and systematics is the lack of a biological species definition. Criteria to be used for defining bacterial species on genetic and biological bases should be able to reveal clear-cut boundaries among clusters of bacteria. To date, DNA-DNA re-association assays and ribosomal RNA sequence comparison have been useful in determining relative evolutionary distances among bacteria but the data are continuous and thus cannot define bacterial clusters as taxonomic units to be called species. Using Salmonella as models, we have looked for definite genetic and biologic uniqueness of clusters of bacteria. Based on our findings that each Salmonella lineage has a unique genome structure shared by strains of the same lineage but not overlapping with strains of other Salmonella lineages, we conclude that this is a result of genetic isolation following divergence of the bacteria. We propose that there should be genetic boundaries between different species of bacteria at the genomic level, which awaits further genomic information for validation.

In order to solve the problem of real-time and accuracy for collecting the traction battery evaluation parameters, including battery voltage, battery current and battery temperature, the data acquisition system based on Field Programmable Gate Array(FPGA) and Universal Serial Bus Protocol (USB2.0) is designed. In this paper, FPGA is used as the microcontroller to control analog to digital(A/D) conversion and USB transmission. Moreover, USB firmware and driver program are explored and achieved. Validation experimental results show that the designed system is high credible. It also shows that the accuracy and speed of data sampling are improved. It is great benefit to evaluate battery status in battery management system.

To provide theoretical basis for the production of ginsenosides by using modern biotechnologies, the comparative studies of the amount of ginsenosides between the crown galls and Chinese medicinal materials of Panax quinquefolium were carried out.Total ginsenosides were determined by spectrophotometry, and the contents of ginsenoside Rb1, Rb3, Rc, Re were determined by HPLC.(1) The total ginsenosides in the crown galls of Panax quinquefolium (aftert 27 days' cultivation) was almost as much as that of Chinese medicinal material of Panax quinquefolium. (2) The contents of ginsenoside Rb1, Re in the crown galls were about half of that in Chinese medicinal materials of Panax quinquefolium, and ginsenoside Rc was about 80%. But the amount of ginsenoside Rb3 in the crown galls of Panax quinquefolium was much more than that in Chinese medicinal materials of Panax quinquefolium as almost 15 times higher.The crown galls of Panax quinquefolium may be a new potential resource for large-scale production of ginsenosides.

A rapidly growing body of information has suggested that NAD (including NAD+ and NADH) and NADP (including NADP+ and NADPH) could be new fundamental factors in cell death: Many studies have indicated key roles of poly (ADP-ribose) polymerases and sirtuins--two families of NAD-dependent enzymes--in cell death; and NAD may also affect cell survival by influencing mitochondrial permeability transition, apoptosis-inducing factor and GAPDH. NAD may further influence cell survival by its effects on calcium homeostasis, gene expression and immunological functions. Due to the crucial roles of oxidative stress in cell death, NADPH may mediate cell death by its major effects on oxidative stress: NADPH is a key factor in cellular antioxidation systems; and NADPH oxidase is also a major generator of oxidative stress. With growing information about the novel biological properties of NAD and NADP, it is likely that new roles of NAD and NADP in cell death and various diseases will be elucidated. The elucidation may not only improve our understanding about the fundamental mechanisms of cell death, but also suggest new therapeutic targets for a variety of diseases.

To investigate the mRNA expression of basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF) in gastric carcinoma and correlation thereof with intratumoral microvascular density (IMD), proliferating cell nuclear antigen labeling index (PCNA LI), tumor invasion and metastasis, and patients' survival.In situ hybridization and immunohistochemistry were used to test the expression of bFGF and HGF mRNA and protein expression of CD34 and PCNA in 118 specimens of gastric carcinoma.The positive rates of bFGF mRNA and HGF mRNA were 57.6% and 52.5% respectively; the positive expression rates of bFGF mRNA and HGF mRNA of the cases at the stage T3-T4, and those with vessel invasion, lymph node metastasis, and distant metastasis were all significantly higher than the positive expression rates of the cases at the stage T1-T2, and those without lymph node metastasis, vessel invasion, and distant metastasis (all P0.05). The mean IMD levels of the patients positive in bFGF and HGF mRNA expression were (46.63 +/- 13.96) and (46.73 +/- 13.34) pieces/0.72 mm2, both significantly higher than those of the patients negative in bFGF and HGF mRNA expression [(34.56 +/- 15.16) and (35.98 +/- 14.92) pieces/0.72 mm2) respectively, t = 4.62, P = 0.000, and t = 4.01, P = 0.000]. The PCNA LI of the of the patients positive in bFGF and HGF mRNA expression was (66.53 +/- 13.61) and (67.56 +/- 13.41) respectively, both significantly higher5 than those of patients negative in bFGF and HGF mRNA expression [(54.79 +/- 10.57) and (55.04 +/- 11.01) respectively, t = 5.83, P = 0.000, and t = 4.91, P = 0.000]. The 5-year survival rates of the patients negative in bFGF and HGF mRNA expression were 60.00% and 67.90% respectively, both significantly higher than those of the patients positive in bFGF and HGF mRNA expression (30.90% and 21.00% respectively, both P = 0.000). IMD, PCNA LI, and bFGF mRNA were all positively related to HGF mRNA (all P = 0.000).bFGF and HGF promote angiogenesis and proliferation of gastric cancer, and in involved in tumor invasion and metastasis. They can be used as markers of prognosis of gastric cancer in clinical practice.

Recently, the pollution from pond aquaculture waste water has become more and more serious. In order to perfectly deal with such problem, the paper discussed the feasibility of using photochemical reactivity to remove pollutants through improving pond aquatic ecosystem from wastewater with the aim of water recycling and zero discharge. A photochemical treatment system (PTS) was designed that used photochemical reactivity to treat the polluted aquaculture wastewater. A spot observation method has been used in discussing the reactivity for the treatment of pond aquaculture wastewater with this system on a shrimp farm in Hainan province of China. The result showed that culture pond with PTS could realize progressive efficiency of pollutant removal without water exchange in a recirculating system, which could perfectly meet the need of environment protection and culture production.

A previous study showed that the cancer mortalities are higher for residents who lived nearby the Songhua River heavily polluted by organic contamination. It is important to determine its risk of carcinogenic potential. Short-term genotoxic bio-assays using Salmonella, Sister Chromatid Exchange (SCE), and Micronuclei (MN) assays were employed to examine the genotoxic activity of ether extracts of water samples taken from the Songhua River. The results of the Salmonella bioassay indicated that there were indirect frame-shift mutagens in the water samples. A dose-response relationship for the SCE and MN assays was obtained. These results showed that organic extracts of water samples have genotoxic activity and the risk of carcinogenic potential to human health. The mutagenesis of water samples had changed compared to the results in 1994-1995. An increasing trend of risk of carcinogenic potential in the Songhua River after ten years should be noted and needs to be studied further.