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Effects of Two Composted Plant Pesticide Residues,Incorporated with Trichoderma viride,on Root-Knot Nematode in Balloonflower

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Agricultural Sciences in China 2009年第4期8卷 447-454页

作者： ZHANG shuang-xi ZHANG xing Biorational Pesticide R＆D Center Northwest A＆F University Yangling 712100 P.R.China

Plant pesticide residues, such as chinaberry （Melia toosendan） residue and sand cypress （Sabina vulgaris） residue, are pesticidal plant materials discarded after the bioactive ingredient has been extracted with organic solvents. The only option for botanical pesticide residue utilization has been as landfill. Chinaberry residue （CBR） and sand cypress residue （SCR） were collected and composted in Yangling, Shaanxi Province, China. We studied the effects of chinaberry residue compost （CBRC）, CBRC incorporated with Trichoderma viride （CBRCT）, sand cypress residue compost （SCRC）, and SCRC incorporated with T. viride （SCRCv） on the root-knot nematode, Meloidogyne incognita, infesting the balloonflower （Platycodon grandiflorum）. Bioassay results indicated that stock solutions of the CBRCT and SCRCT extracts significantly inhibited egg hatching and caused high larval mortality, followed in degree by the CBRC and SCRC extracts. The CBR and SCR extracts caused very low inhibition of eggs and larvae. Supplementing potting mixtures with these four composts reduced the severity of root galling and increased the proportion of marketable roots. The severity of root galling decreased and the average weight of the marketable roots increased with an increase in all the composts when supplemented at rates from 5 to 30%. CBR- and SCR-supplemented pot soils also inhibited the nematodes, but CBR and SCR applied to the soil had a phytotoxic effect and inhibited balloonflower growth. Supplementing field soil with the composts reduced the severity of root galling and the populations of southern root-knot nematodes in the soil. CBRCT and SCRCT clearly enhanced the average weight of the marketable roots by 30.45 and 26.64%, respectively. Continuous supplementation with CBRCT or SCRCT in the same field significantly enhanced the control of the root-knot nematode, and the populations of nematodes continued to decrease with second inoculations. The populations of total Trichoderma spp. were dis

关键词： balloon flower root-knot nematode plant pesticide residue compost compost extract

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A variational method for correcting non-systematic errors in numerical weather prediction

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Science China Earth Sciences 2009年第10期52卷 1650-1660页

作者： SHAO AiMei xi shuang QIU ChongJian Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

A variational method based on previous numerical forecasts is developed to estimate and correct non-systematic component of numerical weather forecast error. In the method, it is assumed that the error is linearly dependent on some combination of the forecast fields, and three types of forecast combination are applied to identifying the forecasting error: 1) the forecasts at the ending time, 2) the combination of initial fields and the forecasts at the ending time, and 3) the combination of the forecasts at the ending time and the tendency of the forecast. The Single Value Decomposition (SVD) of the covariance matrix between the forecast and forecasting error is used to obtain the inverse mapping from flow space to the error space during the training period. The background covariance matrix is hereby reduced to a simple diagonal matrix. The method is tested with a shallow-water equation model by introducing two different model errors. The results of error correction for 6, 24 and 48 h forecasts show that the method is effective for improving the quality of the forecast when the forecasting error obviously exceeds the analysis error and it is optimal when the third type of forecast combinations is applied.

关键词： variational method non-systematic error Single Value Decomposition error correction shallow-water equation model

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Surface-exchange of NOx and NH_3 above a winter wheat field in the Yangtze Delta, China

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Journal of Environmental Sciences 2006年第4期18卷 689-700页

作者： FANG shuang-xi ZHANG Yi MU Yu-jing Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A four-dynamic-chamber system was constructed to measure NOx and NH3 surface-exchange between a typical wheat field and the atmosphere in the Yangtze Delta, China. The average fluxes of NO, NO2 and NH3 were 79, -5.6 and -5.1 ngN/（m^2·s）, and 91, -1.8 and 23 ngN/（m^2·s）, respectively for the wheat field and the bare soil. The NO flux was positively correlated with soil temperature and the fluxes of NO2 and NH3 were negatively correlated with their ambient concentrations during the investigated period. The compensation point of NO2 between the wheat field and the atmosphere was 11.9 μg/m3. The emissions of NO-N and NH3-N from the urea applied to the wheat field were 2.3% and 0.2%, respectively, which indicated that the main pathway of N loss from the investigated winter wheat field was NO. Application of a mixture of urea and lignin increased the emissions of NO, but also greatly increased the yield of the winter wheat.

关键词： NOx NH3, flux surface-exchange

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The updated Bulk Lorentz Factors of Gamma-Ray Burst X-Ray Flares

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Research in Astronomy and Astrophysics 2017年第6期17卷 37-46页

作者： Shao-Qiang xi shuang-xi Yi Yuan-Chuan Zou Fa-Yin Wang College of Physics and Engineering Qufu Normal University Qufu 273165 China School of Physics Huazhong University of Science and Technology Wuhan 430074 China School of Astronomy and Space Science Nanjing University Nanjing 210093 China Key Laboratory of Modem Astronomy and Astrophysics (Nanjing University) Nanjing 210093 China

X-ray flares are the most common phenomena in the afterglow phase of gamma-ray bursts （GRBs） in the Swift era, and are known as a canonical component in X-ray afterglows. In this work, we constrain the Lorentz factor of X-ray flares with an updated sample. We extensively search for X-ray light curves showing flare and jet break simultaneously. A smooth broken power law function is used to fit the jet breaks in 11 GRBs. We also use a smooth broken power law function to fit the profile of X-ray flares, and the total number of the flares is 20. We obtain the lower and upper limits of Lorentz factor （Гx） with the timescale, half-opening angle and mean luminosity of the X-ray flares for interstellar medium （ISM） and wind cases. The lower limits on Px range from tens to a few hundred, and the upper limits are mainly about a few hundred. We also apply the limited Lorentz factor to test correlations of Г0 - γ,iso and Г0 - Lγ,iso for GRBs, and find X-ray flares in the ISM case are much more consistent with those of prompt emission than the wind case in a statistical sense for both correlations. X-ray flares are almost consistent with the trend in the correlations of Г0 - Eγ,iso（Lγ,iso） for prompt GRBs, indicating X-ray flares and prompt bursts may have the same physical origin.

关键词： gamma ray bursts -radiation mechanism: non-thermal

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Prediction for the Multi-band Afterglows of FRB 200428 and its Implication

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Research in Astronomy and Astrophysics 2023年第11期23卷 84-89页

作者： Mei Du shuang-xi Yi Can-Min Deng Pei Wang School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

The physical mechanism of fast radio bursts(FRBs) is still unknown. On 2020 April 28, a special radio burst, FRB200428, was detected and believed to be associated with the Galactic magnetar SGR 1935+2154. It confirms that at least some of the FRBs were generated by magnetars, although the radiation mechanism continues to be *** this end, we study in detail the multiband afterglows of FRB 200428 described by the synchrotron fireball shock model. We find the prediction for the optical and radio afterglows of FRB 200428 is consistent with the observations when considering the post-FRB optical and radio upper limits from the literature. We also show that the follow up detection of the afterglows from fast radio bursts like—FRB 200428 is possible at the radio band,though challenging. Based on our model, one can obtain information about the energy of the fireball, the radiation zone, and the nature of the surrounding medium. That may shed light on the physical mechanism of FRBs.

关键词： stars:magnetars (stars:)gamma-ray bursts:general radiation mechanisms:non-thermal

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Comparative analysis of rapamycin biosynthesis clusters between Actinoplanes sp. N902-109 and Streptomyces hygroscopicus ATCC29253

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Chinese Journal of Natural Medicines 2015年第2期13卷 90-98页

作者： HUANG He REN shuang-xi YANG Sheng HU Hai-Feng Shanghai Institute of Pharmaceutical Industry Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences

The present study was designed to identify the difference between two rapamycin biosynthetic gene clusters from Streptomyces hygroscopicus ATCC29253 and Actinoplanes sp. N902-109 by comparing the sequence and organization of the gene clusters. The biosynthetic gene cluster for rapamycin in Streptomyces hygroscopicus ATCC29253 was reported in 1995. The second rapamycin producer, Actinoplanes sp. N902-109, which was isolated in 1995, could produce more rapamycin than Streptomyces hygroscopicus ATCC29253. The genomic map of Actinoplanes sp. N902-109 has been elucidated in our laboratory. Two gene clusters were compared using the online software anti-SMASH, Glimmer 3.02 and Subsystem Technology(RAST). Comparative analysis revealed that the organization of the multifunctional polyketide synthases(PKS) genes: Rap A, RapB, RapC, and NRPS-like RapP were identical in the two clusters. The genes responsible for precursor synthesis and macrolactone modification flanked the PKS core region in N902-109, while the homologs of those genes located downstream of the PKS core region in ATCC29253. Besides, no homolog of the gene encoding a putative type II thioesterase that may serve as a PKS "editing" enzyme accounted for over-production of rapamycin in N902-109, was found in ATCC29253. Furthermore, no homologs of genes rapQ(encoding a methyltransferase) and rap G in N902-109 were found in ATCC29253, however, an extra rap M gene encoding methyltransferase was discovered in ATCC29253. Two rapamycin biosynthetic gene clusters displayed overall high homology as well as some differences in gene organization and functions.

关键词： Rapamycin Actinoplanes Biosynthetic gene cluster Comparative analysis

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Decoupled drought responses of fine-root versus leaf acquisitive traits among six Prunus hybrids

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Journal of Plant Ecology 2020年第3期13卷 304-312页

作者： shuang-xi Zhou Rob R.Walker Everard Edwards CSIRO Agriculture and Food Glen OsmondSA 5064Australia The New Zealand Institute for Plant and Food Research Ltd Hawke’s BayNew Zealand

Aims Predicting drought consequences on forests and fruit crop plantings requires improved understanding of drought responses of both leaf and fine-root resource acquisitive traits(specific leaf area—SLA,specific root surface area—SRA and specific root length—SRL).We hypothesize their responses are coordinated towards integrated plant resource conservation under severe *** We tested the hypothesis with a greenhouse-based drought experiment on saplings of six Prunus hybrids with a priori known contrasting drought *** were subjected to either control(100%field capacity)or severe drought stress treatment(33%evapotranspiration of hybrid-specific control plants).Sample collections were carried out at 30 and at 60 days after the start of treatments,for both control and stressed *** Findings No hybrid showed concurrent significant decrease of SLA and SRA(or SRL)under severe *** fine-root traits of the six hybrids showed two major drought-response scenarios,in particular:(i)increased root tissue density(RTD)and decreased average root diameter without significant change of SRL and(ii)increased RTD and decreased SRL without significant change of average root *** responses of leaf gas exchange,SRA,SRL and RTD were closely correlated along a gradient towards resource conservation from control to drought-stressed plants in all hybrids,which was orthogonal to another gradient characterized by a hybrid-dependent decrease of *** findings highlight(i)the multi-dimensionality of root-trait drought responses,(ii)the decoupling between leaf economics and leaf hydraulics and(iii)the covariation of leaf and root hydraulics in terms of trait drought *** study contributes to identifying the origin of the multi-dimensionality of root-trait drought response at intraspecific scale,and highlights differential drought–response combinations of leaf and fine-root traits among hybrids to survive under severe soil drou

关键词： multi-dimensional drought response soil water stress specific leaf area specific root length specific root surface area

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Statistical Properties of X-Ray Flares from the Supergiant Fast X-Ray Transients

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Research in Astronomy and Astrophysics 2022年第6期22卷 118-125页

作者： Wen-Long Zhang shuang-xi Yi Yu-Peng Yang Ying Qin School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China Department of Physics Anhui Normal UniversityWuhu 241000China

Supergiant fast X-ray transients are a sub-class of high mass X-ray binaries,in which the compact object is a neutron star and it is accreting materials from its non-degenerate companion *** sample of supergiant fast X-ray transients from XMM-Newton public observations have been intensively studied,and hence the corresponding parameters for identifying X-ray flares have been obtained by Sidoli et al.,such as the rise time,the decay time,the duration time,the waiting time,the peak luminosity,the isotropic energy and the mean *** order to investigate the origin of the X-ray flares from the supergiant fast X-ray transients,we apply the cumulative distribution method with the power-law index dN(x)/dx∝(x+x0)-ax to the target *** then find that the relevant parameters can be well described by the cumulative distribution with indices 1.0-1.9 for IGR J16418-4532,IGR J16328-4726 and IGR J18450-0435,*** finding indicates that the X-ray flares are likely to be produced by the self-organizing critical process,one possible scenario may be due to reconnection in magnetized stellar wind blobs approaching into the magnetosphere of magnetized neutron ***,we suggest that the high mass X-ray binaries with similar X-ray flares likely belong to the self-organized criticality systems.

关键词： X-rays binaries-accretion-accretion disks-stars neutron

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Two New Sterols from Adenophora Stenanthina ***

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Chemical Research in Chinese Universities 1997年第4期13卷 98-101页

作者： HOU Zhen-fu SHIYan-ping MEI shuang-xi LI Yu Institute of Or ganic Chemistry State Key Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou730000

ＴｗｏＮｅｗＳｔｅｒｏｌｓｆｒｏｍＡｄｅｎｏｐｈｏｒａＳｔｅｎａｎｔｈｉｎａＳｕｂｓｐ．ＸｉｆｅｎｇｅｎｓｉｓＨＯＵＺｈｅｎ－ｆｕ，ＳＨＩＹａｎ－ｐｉｎｇ，ＭＥＩＳｈｕａｎｇ－ｘｉａｎｄＬＩＹｕ＊（Ｉｎｓｔｉｔｕｔｅ... 详细信息

ＴｗｏＮｅｗＳｔｅｒｏｌｓｆｒｏｍＡｄｅｎｏｐｈｏｒａＳｔｅｎａｎｔｈｉｎａＳｕｂｓｐ．ＸｉｆｅｎｇｅｎｓｉｓＨＯＵＺｈｅｎ－ｆｕ，ＳＨＩＹａｎ－ｐｉｎｇ，ＭＥＩＳｈｕａｎｇ－ｘｉａｎｄＬＩＹｕ＊（ＩｎｓｔｉｔｕｔｅｏｆＯｒｇａｎｉｃＣｈｅｍｉｓｔｒ...

关键词： Adenophora stenanthina subsp. xifengensis Campanulaceae Steroids Sterols

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Modeling the quasi-periodic oscillation of Swift J1644+57

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Research in Astronomy and Astrophysics 2020年第2期20卷 31-36页

作者： Meng-Meng Zheng shuang-xi Yi Fa-Yin Wang Yuan-Chuan Zou School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China School of Physics Huazhong University of Science and TechnologyWuhan 430074China

A 200-second X-ray quasi-periodicity in the 2-8 ke V band from Swift J1644+57 was found by Reis et *** the onset time of quasi-periodic oscillation(QPO),we show that Swift J1644+57 is a plunging *** QPO may be related to discrete clumps from the accretion disk falling into a supermassive black hole,then the outflow in the jet may be also *** estimate the lifetime of clumps to be about several hundreds seconds and the fraction of clumpy ejecta to be about 30% from the *** other possible model involves the interface between the inflow and jet magnetosphere in the magnetically choked accretion *** and numerical simulations indicate that a magnetic Rayleigh-Taylor and Kelvin-Helmholtz unstable magnetospheric interface can produce a jet-disk QPO *** event may be the first evidence of jet-disk *** observations,the two models are comparable.

关键词： accretion accretion discs gamma-ray burst:general radiation mechanism:non-thermal

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