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Wu J.,Liaoning Forestry Vocation Technical College | Wu J.,CAS Shenyang Institute of Applied Ecology | Qian J.,CAS Shenyang Institute of Applied Ecology | Hou X.,Liaoning Forestry Vocation Technical College | And 3 more authors.
Journal of Arid Land | Year: 2016

Species richness is an important indicator of species diversity. Different sampling intensities will very likely produce different species richness values. Substantial efforts have already been made to explicitly quantify the spatial variability of soil properties in different ecosystems. However, concerns still remain on how to characterize the effect of different sampling intensities on plant species richness within a given region. This study characterized the spatial variability of plant species richness and the species distribution pattern in a 25-hm2 sand dune plot in northeastern Inner Mongolia, China by using an intense sampling method (n=10,000). We also evaluated the overall effect of information loss associated with the spatial variability and distribution patterns of species richness under various scenarios of sampling intensities (n=10,000 to 289). Our results showed that semi-variograms of species richness were best described by the spherical and exponential models. As indicated by the nugget/sill ratio, species richness was different in terms of the strength of the spatial relationship. The different spatial metrics of species richness with increasing sampling intensities can represent different responses of the spatial patterns when compared with the reference set (n=10,000). This study indicated that an appropriate sampling intensity should be taken into account in field samplings for evaluating species biodiversity properly. A sampling intensity of n>2,500 for species richness yielded satisfactory results to resemble the spatial pattern of the above-quantified reference set (n=10,000) in this sand dune region of China. © 2016, Xinjiang Institute of Ecology and Geography, the Chinese Academy of Sciences and Springer - Verlag GmbH.


Liu X.,Northeastern University China | Liu X.,Durham University | Zhao H.,Northeastern University China | Feng Y.,Northeastern University China | And 2 more authors.
Dongbei Daxue Xuebao/Journal of Northeastern University | Year: 2016

Big data of Liaoning forestry pests was adopted, which publicated by General Station of Forest Pest Management, State Forestry Administration. A construction method based on space-time influence domain for insects network was proposed according to the insects occurring complexity in space and time. Taking pine caterpillar (Dendrolimus spp.) as a research sample, the expansion of the time window is determined according to the insects' lifestyles and habits, and the range of influence effect are determined according to the damage of pest. The results show that the proposed pine caterpillar network following the power-law distribution is scale-free, Dendrolimus diffuse fast, the pine caterpillars are more likely to emerge clustered, and the topology of the pine caterpillar network is robust. This analysis which using the complex network method is scientific, and the real-world phenomenon can be reflected in the network construction method. Such a analysis of network science on pine caterpillar network is intended to provide a guidance regarding to forestry pest control strategies. © 2016, Editorial Department of Journal of Northeastern University. All right reserved.


Li Z.-C.,Liaoning Forestry Vocation Technical College
Journal of Clinical Rehabilitative Tissue Engineering Research | Year: 2010

OBJECTIVE: To understand biomechanical characteristics of knee joint ligament to reveal the causes for ligament injury of the knee joint, so as to provide suggestions of knee joint prevention, treatment, functional recovery and reconstruction material optimization for college students during sports exercise. METHODS: A computer-based online search of PubMed database (http://www.ncbi.nlm.nih.gov/PubMed) and Wanfang database (http://www. wanfangdata.com.cn) was performed for related articles published between 2006 and 2010, with the key words "knee joint, biomechanics, sports injury, artificial ligament, material optimization" in English and Chinese. Articles involving biomechanical characteristics of knee joint, general causes, prevention, treatment and functional recovery of knee joint ligament and reconstruction material to repair ligament breakage were included. Repetitive studies were excluded. RESULTS: A total of 566 articles were collected, and 18 were included for further analysis following title reading and abstract screening. CONCLUSION: Ligament injury of the knee joint is common in sports exercise and greatly damages students body quality. Studies of biomechanical characteristics, rehabilitation, and reconstruction material to repair ligament breakage benefit prevention, treatment and functional recovery of knee injury of college students during sports exercise, which also promote students health and carry out positive sports exercise. With developing material medicine, artificial ligament has been used clinically, which obtains favorable effect in short and middle period of time. Biodegradation of polymer in combination with cytokine treatment, in vitro cell culture and gene transfection techniques help to confirm basic theory of ligament repair and substitution. A novel ligament substitution should be developed to reach requirements of artificial ligament.


Tian Z.-D.,Shenyang University of Technology | Gao X.-W.,Northeastern University China | Gong B.-L.,Northeastern University China | Shi T.,Liaoning Forestry Vocation Technical College
International Journal of Automation and Computing | Year: 2015

A network time-delay compensation method based on time-delay prediction and implicit proportional-integral-based generalized predictive controller (PIGPC) is proposed. The least squares support vector machine (LSSVM) is used to predict the current time-delay, the parameters of the least squares support vector machine are optimized by particle swarm optimization (PSO) algorithm, and the predicted time-delay is used instead of the actual time-delay as the parameters of the network time-delay compensation controller. In order to improve the compensation effect of implicit generalized predictive controller (GPC), this paper puts forward an implicit generalized predictive control algorithm with proportional-integral-based (PI) structure and designs the controller based on implicit PIGPC. Through the simulation results, the effectiveness of this design in the paper is verified. © 2015 Institute of Automation, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg


Wu J.,Liaoning Forestry Vocation Technical College | Wu J.,University of Chinese Academy of Sciences | Liu Z.,CAS Shenyang Institute of Applied Ecology | Qian J.,University of Chinese Academy of Sciences | Qian J.,CAS Shenyang Institute of Applied Ecology
Ecological Engineering | Year: 2013

Although a large number of empirical studies have documented the effect of habitat fragmentation on plant diversity, we are far from being able to draw effective conclusions due to a lack of a proper reference point and a large range of patch size. This study aims to test the hypothesis that the effect of habitat fragmentation on plant diversity is non-linear, i.e. there is a shift in the effect of habitat fragmentation on plant diversity from positive to negative (or from negative to positive) with intensifying fragmentation. A sand dune field in a desertified grassland in eastern Inner Mongolia, China, was used as the study site. Eighteen fragmented plots (inter-dune lowlands in the sand dune) and 14 continuous plots (different sizes of grassland) were selected. Plant diversity was estimated by species richness, functional groups and rare species. Logarithmic, power and exponential functions were used to analyze the relationship of species richness, frequency and abundance and plot area. There was a shift from positive to negative in the relationship between habitat fragmentation and species richness with the intensifying fragmentation. The number of plant functional groups increased due to habitat fragmentation, and different functional groups showed distinct responses to the degree of fragmentation. The effect of habitat fragmentation on rare species richness is non-linear, and the effect of habitat fragmentation on rare species population is negative. Our results indicate: (1) thresholds should be taken into consideration when drawing up plant diversity conservation plans; and (2) a single large reserve and several small reserves have different implications in plant diversity conservation. © 2013 Elsevier B.V.


Tian Z.,Shenyang University of Technology | Shi T.,Liaoning Forestry Vocation Technical College
Lecture Notes in Electrical Engineering | Year: 2016

In a networked control system, the time-delay has random and nonlinear characteristics, make the stability of system is hard to ensure. It need the controller in system can accurately predict time-delay. So the precise time-delay prediction of networked control system is an important factor in ensuring the stability of the control system. The echo state networks has good predictive ability on nonlinear time series, it is suitable for predict the time-delay. But parameters of echo state networks learning algorithm has a great influence on the prediction accuracy. An improved genetic algorithm is proposed for parameters optimization of echo state networks. The simulation results show that the prediction accuracy of the predictive method in this paper is higher than the conventional predictive model such as auto regressive and moving average (ARMA) model, least square support vector machine (LSSVM) model and Elman neural network. © Springer-Verlag Berlin Heidelberg 2016.


Zhao X.,Northeast Forestry University | Zhao X.,Liaoning Forestry Vocation technical College | Zhan L.,Liaoning University | Zou X.,Liaoning Forestry Vocation technical College
New Zealand Journal of Crop and Horticultural Science | Year: 2011

An efficient protocol is developed for adventitious shoot regeneration from nodal and leaf explants of the half-highbush blueberry cultivar 'Northland'. In vitro-derived nodal segments are used to form adventitious shoots on pH 5.0 modified woody plant medium (WPM) containing 4 mg/L zeatin, 0.8% (w/v) agar and 2% (w/v) sucrose. This media is deemed suitable based on adventitious shoot multiplication rate and plantlet number and height, and it also achieves the best adventitious shoot induction from leaf explants. Shoots are rooted on half-strength modified WPM containing indole-3-butyric acid (IBA) or a-naphthaleneacetic acid (NAA) and 0 or 0.2% (w/v) activated charcoal, with 2 mg/L IBA and 0.2% (w/v) activated charcoal found best for easy root induction. Rooted plantlets are transferred to plug trays containing 1:1:1 peat:sand:vermiculite adjusted to pH 4.5 with ferrous sulphate, and readily acclimatized under greenhouse conditions. © 2011 The Royal Society of New Zealand.


Wu J.,Liaoning Forestry Vocation Technical College | Liu Z.-M.,CAS Shenyang Institute of Applied Ecology
Chinese Journal of Ecology | Year: 2014

The relationship between habitat fragmentation and biodiversity has been a hot spot in theoretical ecology. This paper elaborated the concept, connotation and measurement of habitat fragmentation. The main theory, content and progress of habitat fragmentation research were also described. Many issues of habitat fragmentation studies were summarized such as different metrics methods of fragmented landscape pattern, inaccurate research methods and undetected non-linear effect of habitat fragmentation. More research should be conducted on the effect of habitat fragmentation on biodiversity in semi-arid areas. Furthermore, the theory and methods of spatial analysis should be widely applied in this area. © 2014, Editorial Board of Chinese Journal of Ecology. All rights reserved.


Zhao X.,Northeast Forestry University | Zhao X.,Liaoning Forestry Vocation Technical College | Zhan L.-P.,Liaoning University | Zou X.-Z.,Liaoning Forestry Vocation Technical College
Plant Growth Regulation | Year: 2011

Previous studies have shown that the late embryogenesis abundant (LEA) gene of Tamarix androssowii can enhance the drought tolerance of transgenic tobacco. In this study, the cloned LEA gene was transformed into half-high bush Northland blueberry in order to enhance its ability to tolerate cold stress. The cephalosporin antibiotics ceftriaxone, cefotaxime and cefazolin were used to optimize transformation of leaf explants, and kanamycin sulfate was used to select for transgenic shoots. PCR and Southern blot analysis confirmed 8 transformants with LEA gene copy numbers ranging from 1 to 7. The LEA chimeric gene was found to be normally transcribed in 6 transgenic lines by RT-PCR. The 8 transgenic lines were tested for cold tolerance by measuring the activities of peroxidase (POD) and superoxide dismutase (SOD), malondialdehyde (MDA) content and relative electrolyte leakage (REL). Overexpression of the LEA gene enhanced the activity of both POD and SOD under low temperature stress conditions. Lipid peroxidation in the transgenic lines was significantly lower than in non-transgenic plants after cold stress, as determined by MDA content and REL. Thus, our findings indicate that the LEA gene confers increased cold tolerance in the Northland blueberry and implicate the metabolic pathways through which it exerts this effect. © 2010 Springer Science+Business Media B.V.

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