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Radio-frequency (RF) inductively coupled negative hydrogen ion source (NHIS) has been adopted in China Fusion Engineering Test Reactor (CFETR) to generate negative hydrogen ions. By introduction the level-lumping method into a three-dimensional fluid model, the volume production and transportation of H- in the NHIS, which consists of a cylindrical driver region and a rectangular expansion chamber, are investigated self-consistently at a large input power (40 kW) and different pressures (0.3–2.0 Pa). The results indicate that with the increase of pressure, the H- density at the bottom of the expansion region first increases and then decreases. In addition, the effect of the magnetic filter is also examined. It is interesting to note that a significant increase in the H- density is observed when the magnetic filter is introduced. As the permanent magnets move towards the driver region, the H- density decreases monotonically, and the asymmetry is enhanced. This work could help to understand the H- distribution under various conditions, and thus to optimize the volume production of negative hydrogen ions in the NHIS.

In this work, a two-dimensional hybrid model, which consists of a bulk fluid module, a sheath module and an ion Monte-Carlo module, is developed to investigate the modulation of ion energy and angular distributions at different radial positions in a biased argon inductively coupled plasma. The results indicate that when the bias voltage amplitude increases or the bias frequency decreases, the ion energy peak separation width becomes wider. Besides, the widths of the ion energy peaks at the edge of the substrate are smaller than those at the center due to the lower plasma density there, indicating the nonuniformity of the ion energy distribution function (IEDF) along the radial direction. As the pressure increases from 1 to 10 Pa, the discrepancy of the IEDFs at different radial positions becomes more obvious, i.e. the IEDF at the radial edge is characterized by multiple low energy peaks. When a dual frequency bias source is applied, the IEDF exhibits three or four peaks, and it could be modulated efficiently by the relative phase between the two bias frequencies. The results obtained in this work could help to improve the radial uniformity of the IEDF and thus the etching process.

To maintain the high-density plasma source in inductively coupled plasma (ICP), very high radiofrequency power is often delivered to the antenna, which can heat the dielectric windows near the antenna to high temperature. This high temperature can modulate the plasma characteristics to a large degree. We thus study the effect of dielectric window temperature on plasma parameters in two different ICP structures based on COMSOL software. The distributions of various plasma species are examined at different dielectric window temperatures. The concentration of neutral gas is found to be largely modulated at high dielectric window temperature, which further affects the electron collision probability with neutrals and the electron temperature. However, the electron density profiles are barely affected by the dielectric window temperature, which is mainly concentrated at the center of the reactor due to the fixed power input and pressure.

The study of the interaction between ion beam and plasma is very important to the areas of inertial fusion energy and high energy density physics. With detailed one-dimensional electromagnetic particle-in-cell simulations, we investigate here the interaction of a laser-accelerated proton beam assuming an ideal monoenergetic beam with a gas-discharge plasma. After the saturation stage of the two-stream instability excited by the proton beam, significant high energy electrons are observed, with maximum energy approaching 2 MeV, and a new two-stream instability occurs between the high energy electrons and background electrons. The trajectories of plasma electrons are studied, showing the process of electron trapping and de-trapping from the wakefield.

A numerical model is developed to study the conductivity effects during the transition from collisionless to collisional regimes in cylindrical inductively coupled argon plasmas at pressures of 0.1–20 Pa. The model consists of electron kinetics module, electromagnetics module, and global model module. It allows for self-consistent description of non-local electron kinetics and collisionless electron heating in terms of the conductivity of homogeneous hot plasma. Simulation results for non-local conductivity case are compared with predictions for the assumption of local conductivity case. Electron densities and effective electron temperatures under non-local and local conductivities show obvious differences at relatively low pressures. As increasing pressure, the results under the two cases of conductivities tend to converge, which indicates the transition from collisionless to collisional regimes. At relatively low pressures the local negative power absorption is predicted by non-local conductivity case but not captured by local conductivity case. The two-dimensional (2D) profiles of electron current density and electric field are coincident for local conductivity case in the pressure range of interest, but it roughly holds true for non-local conductivity case at very high pressure. In addition, an effective conductivity with consideration of non-collisional stochastic heating effect is introduced. The effective conductivity almost reproduces the electron density and effective electron temperature for the non-local conductivity case, but does not capture the non-local relation between electron current and electric field as well as the local negative power absorption that is observed for non-local conductivity case at low pressures.

A field study was conducted to evaluate the effects of ambient ozone (O-3) on an O-3-sensitive poplar (Populus cathayana) by using ethylenediurea (EDU) as a chemical protectant under two soil water treatments (well-watered (WW) and moderate drought (MD, 50-60% of WW in volumetric soil water content). EDU was applied as foliar spray at 0, 300, 450, and 600 ppm. Photosynthetic parameters, pigment contents, leaf nitrogen, antioxidant capacity, growth, and biomass were measured. The 8 h (9:00-17:0) average ambient O-3 concentration was 71.7 ppb, and AOT40 was 29.2 ppm h during the experimental period (9 June to 21 September), which was high enough to cause plant injury. MD had significantly negative effects on P. cathayana, as indicated by reduced photosynthesis, growth, and biomass, and higher MDA contents. On the other hand, EDU significantly increased photosynthesis rate, chlorophyll a fluorescence, V-cmax and J(max), photosynthetic pigments, total antioxidant capacity, tree growth and biomass accumulation, and reduced lipid peroxidation, but there was no significant interaction between EDU and drought for most parameters, indicating that EDU can efficiently protect Populus cathayana against ambient O-3 and the protection was not affected by soil water contents when soil water reached moderate drought level. Among all doses, EDU at 450 ppm provided maximum protection. Comparison of EDU-treated and non-treated P. cathayana could be used as a biomarker systemin risk assessment of the effects of ambient O3 on forest health. (C) 2016 Published by Elsevier B.V.

High-energy-density physics (HEDP) deals with the study of matter under extreme conditions with an energy density higher than 1011 J/m3, corresponding to a pressure of 100 GPa. Such matter exists in abundance in deep interiors of the planets and stars. It also exists for a short duration during nuclear explosion and the loading of high-power-pulsed machines. HEDP is the international frontier of national security, astrophysics and fusion science, and it is also one of the main scientific goals of the high-power laser-facilities, Z-machines and heavy-ion-accelerators. Herein, the HEDP research based on High Intensity heavy-ion Accelerator Facility (HIAF), which is the “12th Five-Year Plan” national major science and technology infrastructure, will be introduced. The HIAF is advocated to provide the world with a heavy-ion beam with utmost high power. The energy and power of one beam pulse is about 100 J and several TW, respectively. With such a high-power heavy-ion beam, heating a solid-state lead sample, for example, could generate homogenous high-energy-density matter with a spatial scale from mm to cm and a temperature of 10 eV, near-solid density, and energy density of 1013 J/m3. Thus, through the HIAF, the generation, properties and evolution of high-energy-density matter can be investigated. This paper also reports the state of the art in the field of HEDP based on HIAF, including the generation and development of high-energy-density matter driven by a high-intensity heavy-ion beam, micro mechanism of interaction between the ion beam and dense matter or plasma, and key diagnostics of the high-energy-density matter driven by a hevy-ion beam.

To evaluate the ozone (O3) sensitivity among peach tree (Prunus persica) cultivars widely planted in Beijing region and explore the possible eco-physiological response mechanisms, thirteen cultivars of peach seedlings were exposed to either charcoal-filtered air or elevated O3 (E-O3, non-filtered ambient air plus 60 ppb) for one growing season in open-top chambers. Leaf structure, stomatal structure, gas exchange and chlorophyll a fluorescence, photosynthetic pigments, antioxidant defense system and lipid peroxidation were measured in three replicated chambers. Results showed that E-O3 significantly reduced abaxial epidemis thickness, but no effects on the thicknesses of adaxial epidemis, palisade parenchyma and spongy parenchyma. Stomatal area, density and conductance were not significantly affected by E-O3. E-O3 significantly accelerated leaf senescence, as indicated by increased lipid peroxidation and more declines in light-saturated photosynthetic rate and pigments contents. The reduced ascorbate content (ASC) was decreased but antioxidant enzyme activity (CAT, APX and SOD) and total antioxidant capacity (TAC) were significantly increased by E-O3 among cultivars. The cultivars with visible symptoms also had more reductions in net photosynthetic rate than those without visible symptoms. Ozone sensitivity among cultivars was strongly linked to leaf mass per area (LMA), antioxidant enzymes activity e.g. SOD, APX rather than stomatal parameters (stomatal area, density and conductance) and ASC. Results could provide a theoretical basis for selecting and breeding the ozone-resistant cultivars of peach trees grown in high O3-polluted regions.

Optical emission spectroscopy measurements of dual-frequency capacitively coupled CF4 plasmas were carried out. The gas temperature (Tg) was acquired by fitting the optical emission spectra of a CF B—X system in 201~206 nm. The atomic fluorine concentration and the electron temperature (Te) were obtained by trace rare gas optical emission spectroscopy and a modified Boltzmann plot technique, respectively. It was found that the gas temperature was about 620±30 K at 50 mTorr and the atomic fluorine concentration increased while the electron temperature decreased with increasing gas pressure and power of high frequency (60 MHz). With increasing low frequency (2 MHz) power, the electron temperature also increased, but the atomic fluorine concentration was insensitive to this change. The generation and disappearance mechanisms of F atoms are discussed.

Fruits of the late-ripening peach cultivar "Wanmi" were bagged at the early period of fruit endocarp hardening, and the bags were removed 1 wk before maturity harvest. The effects of bagging on volatile compounds and polyphenols were studied. Total volatiles and the sum of C(6) compounds, esters from bagged fruits were significantly lower than from nonbagged fruits from the beginning of the final rapid fruit growth stage to maturity. As the most dominant compounds of C(6) compounds and esters, the lower contents of hexanal, trans-2-hexenal, hexyl acetate, cis-3-hexenyl acetate, and trans-2-hexenyl acetate attributed to the lower content of C(6) compounds and esters in bagged fruit. γ-Hexalactone and δ-decalactone were produced earlier in bagged fruits than in nonbagged ones, suggesting that bagging accelerates fruit maturity. Level of γ-decalactone in bagged fruits was significantly lower than in nonbagged fruits at 159 days after full blossom (DAFB), so did δ-decalactone at 166 DAFB. Bagging did not affect chlorogenic acid and catechol contents of either fruit peel or flesh, nor did it affect contents of keracyanin or quercetin-3-rutinoside in fruit flesh during fruit development. However, keracyanin and quercetin-3-rutinoside levels were significantly reduced in bagged fruit peels before ripening compared to nonbagged fruit peels. Considering the large changes in volatiles and polyphenols, the key stage for "Wanmi" fruit maturity was between 126 DAFB and 147 DAFB, about 1 mo ahead of maturity.

Previous work demonstrated that methyl palmitate possesses acaricidal activity against Tetranychus viennensis Boisduval (Acari: Tetranychidae) via an unknown mechanism. Here, the symptoms of methyl palmitate toxicity to T. viennensi were studied to determine the acaricidal mechanism of action of this fatty acid methyl ester. Methyl palmitate caused concentration-dependent mortality of T. viennensis, with a moderate concentration (5 mg/ml) eliciting excitement and premature oviposition without spinning shortly after exposure. Tremors of the appendages were subsequently observed, followed by quiescence after approximately 5 h. Mites developed dorsal fluid exosmosis at 15-20 h posttreatment with reduced egg production, followed shortly thereafter by death. Some typical neurotoxic symptoms such as excitement and convulsions were observed in methyl palmitate-exposed mites, suggesting that methyl palmitate may be a neurotoxin. Compared with other neurotoxic acaricides, methyl palmitate poisoning is a slow process in mites. Transmission electron microscopy revealed serious ultrastructural damage in response to 5 mg/ml methyl palmitate exposure. Autolysis of membranous structures was also observed, especially in the mitochondria, suggesting a novel mode of action for methyl palmitate-induced toxicity.

Using HS–SPME–GC–MS, characteristics of the volatiles of 50 peaches and nectarines representing different germplasm origins were investigated. Ten of these peaches and nectarines were studied in two successive years. Eighty-four compounds were identified. Volatile composition was relatively consistent, but the amount of total volatiles and certain individual compounds varied between years. Moreover, the composition of volatiles and their contents depended on genotypic background and germplasm origin. Total volatiles in wild peaches and a Chinese local cultivar ‘Wutao’ were much higher than in the other groups. All the peaches and nectarines could be classified into four groups by principal component analysis of the volatiles (excluding C6 compounds): ‘Ruipan 14’ and ‘Babygold 7’ with high contents of lactones, Chinese wild peaches and ‘Wutao’ with high contents of terpenoids and esters, seven cultivars with American or European origins with high content of linalool, and others without characteristic composition of volatiles.

Volatile aroma compounds are one of the important characteristics determining fruit quality. Evaluation of volatiles at the germplasm level is useful for future breeding efforts, aimed at improvement of fruit quality, via effects on fruit aroma. The composition and concentration of volatiles in berries of forty-two grape cultivars belonging to seven genotypic groups were evaluated by headspace solid-phase microextraction with GC–MS. Sixty volatiles were detected, of which C6 compounds were the dominant volatiles in V. amurensis grape, neutral cultivars V. vinifera grapes and hybrid grapes between V. vinifera with V. thunbergii or V. amurensis. Alcohols and carbonyls were relatively low in all Vitis germplasm studied. Terpenoids were abundant in V. vinifera with muscat aroma, while esters were dominant in V. labrusca and its hybrids with V. vinifera or V. amurensis. Via principal component analysis, all the grape germplasm studied could be divided into three groups: (1) V. labrusca and its hybrids with V. vinifera or V. amurensis, (2) V. vinifera with muscat aroma and (3) the others, including V. vinifera without muscat aroma plus V. amurensis, and hybrids between V. vinifera and V. thunbergii or V. amurensis. Seasonal quantitative variations of volatiles were observed, but the qualitative volatile composition of the cultivars was consistent.

Benzalacetone synthase (BAS) is a member of the plant-specific type III PKS superfamily that catalyzes a one-step decarboxylative condensation of 4-coumaroyl-CoA with malonyl-CoA to produce p-hydroxybenzalacetone. In our recent work (Ma et al. in Planta 229(3):457-469, 2008), a three-intron type III PKS gene (PcPKS2) was isolated from Polygonum cuspidatum Sieb. et Zucc. Phylogenetic and functional analyses revealed this recombinant PcPKS2 to be a BAS. In this study, another three-intron type III PKS gene (PcPKS1) and its corresponding cDNA were isolated from P. cuspidatum. Sequence and phylogenetic analyses demonstrated that PcPKS1 is a chalcone sythase (CHS). However, functional and enzymatic analyses showed that recombinant PcPKS1 is a bifunctional enzyme with both, CHS and BAS activity. DNA gel blot analysis indicated that there are two to four CHS copies in the P. cuspidatum genome. RNA gel blot analysis revealed that PcPKS1 is highly expressed in the rhizomes and in young leaves, but not in the roots of the plant. PcPKS1 transcripts in leaves were inducible by pathogen infection and wounding. BAS is thought to play a crucial role in the construction of the C(6)-C(4) moiety found in a variety of phenylbutanoids, yet so far phenylbutanoids have not been isolated from P. cuspidatum. However, since PcPKS1 and PcPKS2 (Ma et al. in Planta 229(3):457-469, 2008) have been identified in P. cuspidatum, it is possible that such compounds are also produced in that plant, albeit in low concentrations.

Salidroside, a novel effective adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor, can be derived from phenylalanine or tyrosine. Due to the scarcity of R. sachalinensis and its low yield of salidroside, there is great interest in enhancing production of salidroside by the plant. In this study, a cDNA clone encoding phenylalanine ammonia-lyase (PAL) was isolated from R. sachalinensis using rapid amplification of cDNA ends. The resulting cDNA was designated PALrs1. It is 2407-bp long and encodes 710 deduced amino acid residues. Southern blot analysis of genomic DNA indicated that the PAL gene family is composed of three to five genes in the R. sachalinensis genome. Northern blot analysis revealed that transcripts of PALrs1 were present in calli, leaves and stems, but expression in roots was very low. The PALrs1 under the 35S promoter with double-enhancer sequences from CaMV-Omega and TMV-Omega fragments was transferred into R. sachalinensis via Agrobacterium tumefaciens. PCR and PCR-Southern blot confirmed that the PALrs1 gene had been integrated into the genome of transgenic plants. Northern blot analysis revealed that the PALrs1 gene had been expressed at the transcriptional level. High-performance liquid chromatography indicated that overexpression of the PALrs1 gene resulted in a 3.3-fold increase in p-coumaric acid content, as expected. In contrast, levels of tyrosol and salidroside were 4.7-fold and 7.7-fold, respectively, lower in PALrs1 transgenic plants than in controls. Furthermore, overexpression of the PALrs1 gene resulted in a 2.6-fold decrease in tyrosine content. These data suggest that overexpression of the PALrs1 gene and accumulation of p-coumaric acid did not facilitate tyrosol biosynthesis; tyrosol, as a phenylethanoid derivative, is not derived from phenylalanine; and reduced availability of tyrosine most likely resulted in a large reduction in tyrosol biosynthesis and accumulation of salidroside.

Resveratrol is a natural phytoalexin with special pharmacological and health functions. Stilbene synthase (STS) is a key and rate-limiting enzyme in the biosynthesis of resveratrol that is present only in a limited number of plants. The content of resveratrol from Polygonum cuspidatum is more than 1000 times higher than grapes and peanuts. We speculate that the catalytic ability of different STS may be one of the reasons causing differences in the content of resveratrol. To verify the above speculation, Vitis vinifera stilbene synthase gene (VvSTS) was amplified according to overlap PCR protocol with genomic DNA as template. VvSTS and PcSTS (PcPKS5) were analyzed through heterologous expression in Escherichia coli. The expression products were purified with Ni-NTA sepharose affinity chromatography and desalted through PD-10 column. The molecular weight of the two fusion proteins was about 43 kDa. Enzyme reaction and product analysis showed that the two products were resveratrol. The enzyme kinetic analysis showed that the catalyze efficiency (Kcat/Km) of PcPKS5 was 2.4 times of the VvSTS. Our findings confirms that STS from certain plants has much higher catalytic capability.

During the course of pathogens penetrating the plant cell, besides of chemical secretion, the pathogens may cause mechanical signal by the physical pressure on the plant cell. In the current study, we took the stress as the mechanical signal elicitor to find the effect of plant resistance induced by stress. The results showed that an appropriate stress stimulation can evidently improve the plant resistance. However, disruption the plasma membrane–cell wall adhesion will absolutely eliminate this kind of inducement effect, which suggests that the plant resistance inducement by stress depend on the adhesion of plasma membrane–cell wall. Also we found that stress stimulation may cause synthesis of lignin and increase the activity of phenylalaninc ammonial lyase (PAL) chitinase and β-1,3-glucanase obviously. The results showed that stress stimulation may not only enhance ability of the plant cell resistant to pathogen penetration but also elicit the accumulation of pathogens suppression or antimicrobial chemical substance in the plant cell.

Progress of the theoretical studies on the ion sheath dynamics in plasma source ion implantation (PSII) is reviewed in this paper. Several models for simulating the ion sheath dynamics in PSII are provided. The main problem of nonuniform ion implantation on the target in PSII is discussed by analyzing some calculated results. In addition, based on the relative researches in our laboratory, some calculated results of the ion sheath dynamics in PSII for inner surface modification of a cylindrical bore are presented. Finally, new ideas and tendency for future researches on ion sheath dynamics in PSII are proposed.

Technological developments in stereo image matching have advanced from traditional area-based to feature-based matching and lately to structural matching. This paper introduces a newly developed matching method utilizing structural matching. An evaluation function based on the joint probability of a possible match is derived. An informed tree search method is applied to find the best match. In order to keep the search time acceptable for photogrammetric applications, a series of strategies have been developed and integrated into the search method. Procedures for extraction of structural descriptions and an algorithm for rotation-invariant correlation are presented. In combining all these tools, the fully automated matching of image features is realized without any a priori information. Several tasks like relative image orientation, image matching of non-metric images and tie point measurement in aerotriangulation, which were fully automated by using the structural matching approach, are presented. The results indicate that structural matching techniques can achieve a very high level of automation in digital photogrammetry.

Salidroside, the 8-O-beta-D-glucoside of tyrosol, is a novel adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor. Due to the scarcity of R. sachalinensis and its low yield of salidroside, there is great interest in enhancing the production of salidroside by biotechnological process. Glucosylation of tyrosol is thought to be the final step in salidroside biosynthesis. In our related works, three UGT clones were isolated from the roots and the cultured cells. Our intention was to combine the catalytic specificity of these UGTs in vitro in order to change the level of salidroside in vivo by over-expression of the above UGTs. However, as the aglycone substrate of salidroside, the biosynthetic pathway of tyrosol and its regulation are less well understood. The results of related studies revealed that there are two different possibilities for the tyrosol biosynthetic pathway. One possibility is that tyrosol is produced from a p-coumaric acid precursor, which is derived mainly from phenylalanine. The second possibility is that the precursor of tyrosol might be tyramine, which is synthesized from tyrosine. Our previous work demonstrated that over-expression of the endogenous phenylalanine ammonia-lyase gene (PALrs1) and accumulation of p-coumaric acid did not facilitate tyrosol biosynthesis. In contrast, the data presented in our recent work provide in vitro and in vivo evidence that the tyrosine decarboxylase (RsTyrDC) is most likely to have an important function in the initial reaction of the salidroside biosynthesis pathway in R. Sachalinensis.

Plant type III polyketide synthase (PKS) generates backbones of a variety of plant secondary metabolites with diverse functions, and has long been models to elucidate the relationship between the three-dimensional structure and function. More than 80 type IIII PKS crystal structures with different functions have been reported in Protein Data Bank, including the crystal structures of the well-studied Chalcone Synthase of plant type III PKS, as well as the 6 other kinds of PKSs in the family, which are critical for understanding the structural basis for diverse starter molecule selectivity, polyketide chain length and the cyclization reaction. Structure-based analysis and site-directed mutagenesis are foundation for the investigation of enzyme engineering, genetic and metabolic engineering. This review summarized 7 plant-specific type III PKS in the aspects of their crystal structures and functions.

We identified acaricidal compounds in Inula japonica Thunberg (Asteraceae) that were effective against carmine spider mite, Tetranychus cinnabarinus (Boisduval). Petroleum-ether extracts from I. japonica were toxic to T. cinnabarinus, with a 50% lethal concentration (LC50) value of 1.18 mg/ml. Silica gel column chromatography was used to separate the acaricidal components. Seventeen of 38 fraction groups had mite mortality rates >50%, nine fraction groups had rates >60%, and three fraction groups had rates >80% at 2 mg/ml. The major volatile compounds in the bioactive fraction groups were identified by gas chromatography-mass spectroscopy, and beta-sitosterol (1), stigmasterol (2), lupeol (3), and alpha-amyrin (4) were identified and determined to have acaricidal activity against T. cinnabarinus in vitro.

The development of the stone and formation of peach (Prunus persica) fruit were explored in this work using a proteomic approach. Sixty-eight proteins with different expression patterns were identified in both the endocarp and mesocarp during early fruit development (from 28 to 59 days after flowering) and the majority were involved in primary or secondary metabolism. In contrast to most proteins associated with primary metabolism in the endocarp, whose expression is down-regulated, expression of pyruvate dehydrogenase (PDH) unexpectedly increased exponentially. Moreover, its expression pattern was linearly positively correlated with the exponentially growing lignin content (R = 0.940), which suggests that PDH may play a role in endocarp lignification. Our data also revealed different spatiotemporal expressions of enzymes involved in the lignin and flavonoid pathways that provided proteome-level evidence to support the hypothesis that these two pathways are competitive during endocarp development. In addition, we observed endocarp-specific oxidative stress and propose that it may act as a stimulating factor in activating lignification and subsequent programmed cell death in the endocarp.

The extracts of S. chamaejasme were reported to have strongly acaricidal activity against T. cinnabarinus, but the mode of its action against mites is unclear. In this study, the effects on T. cinnabarinus caused at subcellular level by S. chamaejasme extracts were evaluated by transmission electron microscopy. Exposure to S. chamaejasme extracts, bilayer membrane detached and nuclear condensed. The crista of mitochondria, the stacking of Golgi cisternae, and endoplasmic reticulum became disintegrated partly. The arrangements of the muscle cells also became irregular and loose. The above-mentioned subcelluar structure change of T. cinnabarinus may be signs of dysfunction of the nervous system, digestive system, and so on. The changes of the activity of the priority target enzyme of the insecticides-Glutathione peroxidase

Methyl palmitate has showed acaricidal activity to Tetranychus cinnabarinus in our previous studies. However, the acaricidal mechanism of methyl palmitate to T. cinnabarinus is unknown. It was presumed that methyl palmitate may play its acaricidal activity to T. cinnabarinus by interfering the biological function of muscarinic receptors. In our studies, the most important muscarinic receptor subtypes M 1 , M 2 and M 3 were detected in the methyl palmitate treated T. cinnabarinus by immunoblotting method. Subsequently, the two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (2D SDS-PAGE) method was used to analyze the change of the protein expression patterns in T. cinnabarinus in response to methyl palmitate treatment to preliminarily discuss its action mechanism. About 19 protein spots with approximately 2-fold increased density, about 31 protein spots with approximately 2- fold reduced density, about 14 disappeared protein spots, and about 13 novel protein spots were detected in the 2D SDS-PAGE gels of the methyl palmitate treated T. cinnabarinus compared to the control. Methyl palmitate may play its acaricidal activity on T. cinnabarinus by affecting muscarinic receptors related signal transduction, and changing the protein expression patterns in T. cinnabarinus.

The communities and diversity of the beneficial insects on jujube trees were studied in jujube sites intercropped with pasture in Taigu, Shanxi province of China. The results showed that 8 orders, 25 families, 64 species and 5112.33plusmn30.65 individuals of insect natural enemies were found in the jujube sites intercropped with pasture site, while the corresponding numbers were 8, 35, and 3126.33plusmn23.36 in the jujube sites without pasture. The intercropped pasture site had significantly (P < 0.05) more beneficial insects than the non-intercropped site. The dominant species were Inocellia sp., Coccinella septempunctata, Chrysopa shansiensis, and Anysis saissetiae. The diversity and the evenness of the beneficial insect community in the intercropped site were significantly higher (P < 0.05) than those in the non-pasture sites. There were significantly smaller (P < 0.05) infestation rates of the fruit borers and significantly higher (P < 0.05) parasitism rates of the fruit borers in jujube orchards intercropped with pastures than that of no pastures in jujube orchards. Significantly greater (P < 0.05) net income was recorded from the treatments with pastures than the no pastures in jujube orchards. The results suggested that the structures and functions of beneficial insects were improved in the jujube sites intercropped with pasture than in the jujube sites without pasture.

Deterioration of peach fruit quality because of split-pit formation had bad influence on market (1). Though many studies have mentioned the mechanism of split-pit formation, further studied are still needed to uncover the development mechanism of endocarp cell during pit hardening process, especially the Programmed cell death (PCD) process of peach endocarp cell. Here, the development of the peach endocarp cell from the two Chinese peach varieties "Jingyu" and "Okubo" was detailedly studied to understand the PCD of endocarp cell during the lignin formation process. According to our morphology observation using transmission electron microscopy, the PCD process of the endocarp cell, characterized by vacuolar enlargement, might have been initiated as early as eight days after full athesis (maybe even more earlier), which is earlier than that of the split-pit formation process. In our studies, almost all the endocarp cell organelles were found to degenerate at forty days after full athesis, when thickening of the endocarp cell wall was also observed. Furthermore, the involvement of hydrolytic enzymes, in particular proteases and nucleases, in the autolytic process of PCD of peach endocarp cells was quantitatively analyzed during pit hardening process. The peach endocarp protein was found to be rapidly degraded by newly expressed proteases since 35 days after full athesis. Elevation of nuclease activities was found to be also coupled with PCD of peach endocarp cells. Furthermore, DNA degradation was found to happen earlier than RNA degradation and hydrolyzing of endocarp soluble protein during the peach pit hardening process.

Our previous studies showed that methyl palmitate had the acaricidal activity to T. viennensis. However, the mechanism of action of methyl palmitate on T. viennensis is unknown. Here, the toxicosis symptoms of T. viennensis exposed to methyl palmitate were studied to preliminarily uncover the acaricidal mechanism of methyl palmitate. Methyl palmitate caused dose-dependent mortality of T. viennensis in our studies. A moderate dose of methyl palmitate (5 mg/mL) initially elicited excite, and early oviposit without spinning. After a few hours, limb twitching was observed, and this was followed by a stage of depressed activity in about 5 hours. Subsequently, the mites developed a condition, which had the outward appearance of exosmosis on the back of the mites during the 15 th -20 th hr, and reduced eggs production. The mites eventually died in a few hours. Some typical neurotoxin symptoms such as excitement and convulsions were observed on the mites exposed to methyl palmitate. Methyl palmitate might be a type of neurotoxin. Compared to other neurotoxic insecticide, poisoning with methyl palmitate is slow in mites. Furthermore, the effects caused at sub cellular level by methyl palmitate were evaluated by transmission electron microscopy. Serious damage in ultra structure was observed at a concentration of methyl palmitate (5 mg/mL). Autolysis of membranous structure was observed, especially in mitochondria, which may imply a novel action of methyl palmitate.

Few studies were mentioned to illustrate the role of plant hormones-IAA and ethylene in split-pit formation. Here, a random sample of 100 developing fruits from 7-year-old early maturing nectarines (Prunus persica L. Batsch cv. Ruiguang 5) was used as test material. The shape index and growth index of the sampled nectarines was comparatively analyzed to show the relation between fruit un-uniform growth and their split-pit formation. The split-pit fruits were found to have a higher degree of un-uniform growth than that of the normal fruits, which were demonstrated by higher ratio of transverse diameter/lateral diameter and bigger difference between the flesh thickness of the two sides in the middle part of the fruits (along the line of the transverse diameter) about twelve weeks after full anthesis (p < 0.05). Subsequently, a higher degree of unbalanced distribution of IAA and especially ethylene was observed in the split-pit fruits compared to the normal fruits, which may correlate with un-balanced expansion of the nectarines flesh. Higher concentration of IAA and especially ethylene was found in the middle part of the split-pit fruits than those in the sutures, while those in the normal fruits were not significant. Furthermore, the caliosity was specifically observed in the internal surface of the split-pit nectarines endo carp as early as four weeks after full anthesis, but not in the normal nectarines. The occurrence of caliosit in the endo carp may be an early signal of spilt-pit.

In order to realize the differentiated mechanism of mesocarp and endocarp in stone fruits, the profiling of protein expression in mesocarp and putamen of peach were analyzed by two-dimensional electrophoresis (2-DE) to explore the whole cellular milieu of proteomic variety. Peach fruits around 60 days after anthesis were adopted in this observation. The total protein was extracted by TCA/ cold acetone precipitation, and isolated by immobilized pH gradient (IPG) based on 2-DE routine. After silver staining, the gels evaluated operating image analysis software. Considerable high resolution and reproducible 2-DE patterns were obtained successfully. 1273plusmn101 and 1292plusmn115 protein spots were detected respectively from 2-DE patterns of mesocarp and putamen that pH 5~8 IPG strips were practiced in the process of isoelectric focusing. 65 spots of aggregate matched protein spots were present in both patterns of mesocarp and endocarp, and 30 spots showed 2-fold(t-test, p

Most plants could produce bioactive substances including alkaloids, flavonoids, terpenes and relative materials, which are poisonous or have antifeedant effect to herbivorous animals, including some insects. Some well-known pesticides originated from plant bioactive substances have been successfully identified and used, for example, the azadirachtin from neem, nicotine from tobacco, rotenone and deguelin from derris, and pyrethrin from pyrethrum. It's necessary to extract, separate and identify single compounds from plants with biological activity in order to use them directly on crop protection, or to use them as model to synthesize new pesticides without pollution. The green walnut husks contain many kinds of bioactive compounds. By now more than 16 kinds of important components have been found, including tannin, walnuts quinone (juglune), nuts Glycoside (juglanin), alpha-hydride quinone walnuts (alpha-Hydrojuglone) and beta-hydride quinone walnuts (beta-Hydrojuglone), naphthalene Qian (naphthazarin), gallic acid, walnuts drunk alkaloids (C 10 H 8 O 3 ), 1, 4-naphthoquinone and some pigments. We have found that the petroleum-ether extracts of walnut have strong acaricidal activity, but the major compounds of the extracts and the structures of the compounds are unclear. Here we isolated one bioactive fraction G 7 from the green walnut husks which have better acaricidal activity and identified the structure of the compound. The fraction was found to be a signal compound by two-dimensional thin-layer chromatography and High Performance Liquid Chromatography (HPLC), and the HPLC analysis also showed the absorbance peak at 222 nm wavelength of G 7 was the same as that of methyl palmitate reported by Moshitzky and the molecular weight of G 7 was identified by mass spectrometry, and the result showed the G 7 have the same M W as methyl palmitate. Furthermore the molecular structure was analyzed with the nuclear magnetic resonance spectroscopy and the infrared spectrum. It was found that G 7 had the same molecular formula as methyl palmitate C 17 H 34 O 2 . Then, G 7 was compared with methyl palmitate through thin-layer chromatography and HPLC, and it was found that G 7 had the same Rt value 0.6 on TLC and the same absorbance peak at 222 nm wavelength in HPLC as methyl palmitate. So the G 7 fraction was confirmed to be the methyl palmitate.

By using community structural characteristic indices and principal component analysis, this paper studied the community structure and its dynamics of predatory arthropod in the jujube orchards intercropped with Astrugalus complanatus, Trifolium repen, Lotus comiculotus, and Medicago sativa. The results showed that in all test jujube orchards, spider and predatory insects were the predominant components of the predatory arthropod community, and their relative abundances were 48.3% - 52.7% and 38.8% - 44.4% , respectively. There were significant differences (P0.05) in the mean density, diversity, and evenness of the most common predatory arthropod groups in the jujube orchards intercropped with different herbage species, with the sequence of intercropped with Lotus comiculotusMedicago sativaAstrugalus complanatuTrifolium repens, but for dominant concentration index, the sequence was intercropped with Trifolium repensAstrugalus complanatuMedicago sativaLotus comiculotus. The average density of predatory spiders was significant higher (P0.05) than that of predatory insects in all test jujube orchards. The individuals of Coccinellidae, Pentatomidae, inoccllidae, Chrysopidae, Thomisidae, Araneidae and Phytoseiidae played the dominant role in the community.

Leaf samples of six tree species were collected along urban roadsides and a campus site in Beijing for measurement of polycyclic aromatic hydrocarbons (PAHs). PAHs in leaves were attributed to two fractions, leaf cuticles and inner leaf tissues, using sequential extraction. Total concentrations of 16 PAHs in the cuticles and the inner tissues were 69.3+/-64.6 microg g(-1) (d.w.) and 1.07+/-0.2 microg g(-1) (d.w.) at roadside and 57.5+/-52.6 microg g(-1) and 0.716+/-0.2 microg g(-1) on campus, respectively. The lipid-normalized inner tissue PAHs varied from 5.8 microg g(-1) to 15.0 microg g(-1). Similarities in PAH spectra between leaf cuticles and airborne particles and between the inner tissues and gaseous phase imply that airborne particulates and gaseous PAHs are likely the sources of PAHs for cuticles and the inner tissues, respectively. Difficulty in migration of heavier PAHs into inner tissues could be another reason.

To effectively control the scale insects in jujube orchards, a field study was made on the population structure and niche of Pseudococcus comstock Kuwane, Ceroplastes japonicus Green and Quadraspidiotus perniciosus Comstock in the jujube orchards intercropped with wheat in Taigu area of Shanxi Province. The results showed that at the early development stage of jujube trees, these three kinds of scale insects mainly distributed on the southeast direction of the lower and central parts of the tree crown, and P. comstock was the dominant species, with a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects. At the mid-stage of jujube trees development, these scale insects mainly distributed on the northwest direction of the upper part of the tree crown, C. japonicus had a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects, and the niche proportional similarity and interspecific competition of the three kinds of scale insects were not obvious. At the later stage of jujube trees development, there was no significant difference (P0.05) in the population structure of the three kinds of scale insects on the different parts and directions of tree crown, but the density of Q. perniciosus was bigger, and C. japonicus had a wider breadth of two-dimensional temporal-spatial niche. The average values of niche proportional similarity and interspecific competition of the three kinds of scale insects were smaller (P0.05) at the later development stage of jujube trees. Therefore, P. comstock should be controlled at the early development stage of jujube trees, all the three kinds of scale insects should be controlled selectively at the mid-stage of jujube trees development, and their overwinterings should be decreased by all means at the later development stage of jujube trees.

Image matching is a basic issue in computer vision and in digital photogrammetry. For non-metric images the area based and the feature based matching methods are not so suitable as for aerial images, because there is usually no initial values available. In this paper a structure based image matching method is introduced, which can recognize the corresponding image objects fully automatically without knowing any a priori information and without having any relation assumptions about the digital image. Some examples for the application of this matching method to the non-metric images in close range photogrammetry and to the SPOT and MOMS remote sensed images are demonstrated. The results show that the highest automation level of image matching have been reached with the developed method.