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2014 No. 1

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Article
Decompositions for a class of 5×5 separable quantum states
HUANG Xiao-fen
2014, (1): 1-8.
Abstract:
This paper studied certain quantum states for which the PPT criterion was both sufficient and necessary for separability. A class of 55, bipartite mixed states was prestented and the conditions of PPT for these states were derived. The separable pure state decompositions of these states were explicitly constructed when they were PPT, so we can judge a class of states entangled or not by this method.
On chromatic number of { 2K1+K2 , C4 }-free graphs
DUAN Fang, ZHANG Wei-juan
2014, (1): 9-12.
Abstract:
In this paper, the structural characterization of { 2K1+K2,C4 }-free graphs was given according to their independence numbers, and the linear upper bound on chromatic number of { 2K1+K2,C4 }-free graphs was obtained in terms of their clique number.
Vulnerable European option pricing with the time-dependent for double jump-diffusion process
LYU Li-juan, ZHANG Xing-yong
2014, (1): 13-20, 26.
Abstract:
Based on Merton's structured credit risk model, derivatives pricing with rival unilateral default risk was studied in this paper. Assuming that underlying asset price and assets-liabilities of sellers follow double jump-diffusion process, where risk-free interest rate $r(t)$, volatility of asset $\sigma(t)$ and dividend yield $d(t)$ are time-dependent, vulnerable European options pricing model under double jump-diffusion process was established using the structured method, the analytical expressions of options price was obtained using It\^{o} lemma and the trunformation of the equivalent martingale measure.
Relations between solutions of two classes of differential equations with entire function coefficients and functions of small growth
SUN Gui-rong
2014, (1): 21-26.
Abstract:
This paper was devoted to studying two classes of second order linear differential equations with entire function coefficients by using the value distribution theory. The relations between functions of small growth and the solutions of the equations, as well as, their 1st and 2nd derivatives investigated. The results improve some previous works.
Lower diameter estimate for a special quasi-almost-Einstein metric
HU Ling-juan, MAO Jing-jing, WANG Lin-feng
2014, (1): 27-35.
Abstract:
The weighted Myers' theorem gives an upper bound estimate for the diameter of a complete Riemannian manifold with the $\tau$-Bakry-\'{E}mery curvature bounded from below by a positive number. The lower bound estimate for the diameter of a compact manifold is also an interesting question. In this paper, a gradient estimate for the potential function of a special $\tau$-quasi-almost-Einstein metric was established by using the Hopf's maximum principle. Based on it, a lower bound estimate for the diameter of this metric was derived. The result generalizes Wang's lower diameter estimate for compact $\tau$-quasi-Einstein metrics.
Determining the topology of real intersection of algebraic surfaces
GAO Ben, CHEN Yu-fu
2014, (1): 36-46.
Abstract:
This paper gave an algorithm for computing in an efficient way the topology of the real intersection of algebraic surfaces, which are defined by a finite family of trivariate polynomials with coefficients in $\R$. The algorithm is based on the computation of the graphs which are the intersection of at most two projections. For this purpose, some conditions, which be obtained by some linearly change of coordinates were fultiued, and some methods for checking these conditions were presented.
Public-key encryption and certificate-based encryption from lattice
LI Jun, QIAN Hai-feng, LI Xiang-xue
2014, (1): 47-59.
Abstract:
Certificate-based encryption (CBE) combines the advantages of identity-based encryption and that of public key infrastructure. However, CBE based on traditional mathematical assumptions cannot defeat quantum attacks. This paper aims at constructing a lattice-based CBE which is post-quantum: First constructed a lattice-based public key encryption (PKE); then used this PKE to construct a lattice-based CBE. Finally, it was proved that the ciphertexts generated by our CBE are indistinguishable from random against chosen-plaintext attacks (namely, INDr-CBE-CPA secure) by assuming that the learning with errors (LWE) problem is hard. This scheme is the first known lattice-based CBE so far.
Belongingness of Chinese dialect speech recognition based on deep neural network
JING Ya-peng, ZHENG Jun, HU Wen-xin
2014, (1): 60-67.
Abstract:
Based on the modified QuickNet software, we proposed a supervised DNN layerwise pre-training method for dialect speech recognition. The pre-training will start from a 3-layer neural network till the maximum layer, during which we will do supervised training. The initial weights of a new layer are composed of the partial trained weights of lower level network and the randomized weights closed to the output layer. Then we will do traditional back-propagation training when the initial weights of the maximum layer network are obtained. This method achieved a relatively higher recognition rate compared with normal neural network training and can be used in mobile speech recognition apps, the recognition of dialects speech and so on.
Impact of the Beijing-Shanghai high-speed rail on the spatial pattern of the regional road accessibility
JIANG Hai-bing, ZHANG Wen-zhong, LI Ye-jin
2014, (1): 68-78, 89.
Abstract:
This paper discussed the spatial differentiation of the road accessibility under 〖JP2〗the effect of Beijing-Shanghai high-speed rail (HSR). Firstly measured accessibility changes in the spatial distribution of four different accessibility indicators, computed and mapped using a GIS support. The accessibility maps described both the possible benefits and their spatial distribution of the region. Subsequently measured the transport equity by calculating a set of inequality indices of the accessibility distribution and estimated whether the disparities in regional accessibility are increased after the implementation of the HSR. Finally we applied the GIS based technique to calculate the service population scale of every station. The results showed that the HSR obviously improve the overall road accessibility level, reducing greatly total travel time among the central cities. However, it leads to more polarized accessibility patterns of the spatial development which indicated that various regions obtain unbalanced accessibility gain from the HSR, establishing island or corridor spatial patterns with the highest lever accessibility which replaces the ellipse concentric circle shape of road accessibility spatial structure. In addition, the HSR contributes to enlarging the service market demarcation and broadening regional labor markets of main central cities along the line in short time distances and promote many urban agglomerations to facilitate co-operation. Moreover, the HSR stations become the rapid traffic network nodes and the hub of the social and economic activities.
Effects of typhoon disturbance on the litter production in an evergreen broad-leaved forest in the Tiantong, Zhejiang
WANG Zhang-hua, WANG Xi-hua, SHEN Guo-chun
2014, (1): 79-89.
Abstract:
To understand the effects of typhoon disturbance on the production, composition, temporal dynamics of litter in subtropical evergreen broad-leaved forest, a 5-year study from January 2008 to December 2012 on two types of evergreen forests, C. fargesii community and S. superba community, in Tiantong, Zhejiang, was carried out. Average annual litterfall are 6.465 thm-2 and 6.947 thm-2 in C. fargesii community and S. superba community, respectively. Annual litter production and monthly litterfall in typhoon season were both significantly higher in typhoon years than that in normal years. Orders of proportions of different sorts litterfall in the two types of communities are leaves twigs detritus flowers barks. The total leaves production accounted for about 70% of total litter. Proportion of twigs reached about 17%. Proportion of leaves declined from typhoon years to normal years, while the proportion of twigs had an opposite trend. The dynamics of monthly litter production in both communities followed a bimodal distribution (with peaks in April-May and October-November) in normal years, and trimodal distribution (with an extra peak in typhoon season.) in typhoon years. The dynamic of monthly leaves production was different between the two types of communities in different typhoon years. It had two peaks in C. fargesii community and had three peaks in S. superba community in the years (2008, 2009 and 2011) with weak typhoon disturbance. However, it showed three peaks in both communities in the year (2012) with strong typhoon disturbance. These results suggested that typhoon disturbance can change the dynamics of litterfall in subtropical evergreen forest, and these impactions may various in different types of communities under different strengths of typhoon.
Characteristics of sediment load and runoff in the upper, middle and lower reaches of the Yangtze River and their relationship
WANG Yi-bin, LI Jiu-fa, ZHAO Jun-kai, YAO Hong-yi, GUO Xiao-bin, CHEN Wei
2014, (1): 90-98.
Abstract:
The related data from Yichang, Hankou and Datong gauging stations were collected from 19502010 to analyze the characteristics of temporal and spatial variations of the runoff and suspended sediment load in different reaches of the Yangtze River. Multi-year average of runoff (19512010) were 4.321011 m3, 7.071011 m3 and 8.961011 m3 at Yichang, Hankou and Datong gauging station, respectively. The runoff from the upper reaches of the Yangtze River was as much as that from the middle and lower reaches. Multi-year average runoff was fluctuant with no significant trend, but the difference of runoff between flood season and drought season was minimized by the construction of the Three Gorges Dam. On the other hand, multi-year average of suspended sediment load at Yichang Hankou and Datong gauging station were 4.34108 t, 3.59108 t and 3.90108 t, respectively, indicating that the main sources of suspend sediment was the upper reaches of Yangtze River. With the decline of suspended sediment load since 1980s, especially in the flood seasons, the suspended sediment load at Yichang, Hankou and Datong gauging station decreased respectively by 0.54108 t, 1.17108 t and 1.52108 t. Because of the resuspension of sediment in riverbed and river shoal and the sediment supply from the lakes along the Yangtze River, the decreases in the suspended sediment load of different grain size levels were unequal. A good linear relation was found between the suspended sediment load with grain size larger than 0.1 mm and runoff while the linear relation was weaken with the finer of grain size. This was in line with the relative theories of river dynamics. The dispersion grew up from the upper reaches to the lower reaches. This study is very helpful to understand the recent changes in the relationship between the runoff and suspended sediment load under human interventions.
Variation of particulate amino acid in the Suzhou River and the Huangpu River in Shanghai
SHEN Bing-liang, CUI Ying, ZHU Zhuo-yi, WU Ying
2014, (1): 99-106.
Abstract:
Surface particulate samples were collected quarterly in 2007 from four sampling points of Suzhou River and Huangpu River for particulate amino acids (PAA) analysis. The comparison among the four sampling sites were made for general parameters (such as particulate organic carbon (POC), particulate organic nitrogen (PON)) and particulate state amino acid parameters (D and L amino acid and degradation index). The results showed that the amino acid changed more dramatically in Suzhou River. Inferred from the variations of Degradation Index (DI), the source of the particulate amino acids in July is the freshest in the both rivers. A good negative correlation relationship between D-Amino acid and DI suggests the variation of bacteria-derived D-AA during the degradation process.
Comparative study on the adaptability of Alnus trabeculosa and Phragmites australis in tidal wetland
ZHANG Hai-yan, WANG Tian-hui, LU Jian-jian
2014, (1): 107-115, 122.
Abstract:
Self-designed experimental mesocosm for semidiurnal tidal simulation was used to compare the effect of different submergence time on photosynthesis process and physiological characteristics of Alnus trabeculosa and native species (Phragmites australis). The results showed that A. trabeculosa and P. australis have similar decreasing tendency in Stomatal conductance (Gs), Net photosynthetic rate (Pn) and Transpiration rate (Tr) with increasing submergence time; however, the water use efficiency (WUE) of these two species showed the tendency of first increased and then decreased, suggesting that the increasing submergence time promoted the WUE of A. trabeculosa and P. australis in some degree. With daily submergence time increasing, POD activity and MDA content of A. trabeculosa decreased and increased, respectively; POD activity of P. australis first increased and then decreased; however, MDA content of P. australis hasnt significant difference. A. trabeculosa showed the similar tolerance to the periodic inundation of tidal wetland, which suggests that A. trabeculosa can be also used to construct ecological engineering in Chongxi wetland.
ATR-Chk1-Cdc25 involved in the regulation of Dictyostelium discoideum during G2/M cell cycle
CHENG Xiao-feng, HOU Lian-sheng
2014, (1): 116-122.
Abstract:
The cell proliferation of wild type KAx-3 and mutant type RNAi-allC observed by light microscope and cell counting, The latter was divided 8 time faste than the former. To evaluate the reason why RNAi-allC cell cycle shortened, the function of ATR-Chk1-Cdc25 signaling pathway were explored by quantitative PCR and western blot techniques. The results showed the differences of ATR, Chk1, Cdc25 in mRNA contents and protein level existed in KAx-3 and RNAi-allC cells, that is, the expression of ATR and Chk1 ratio of RNAi-allC to KAx-3 was 0.69〖DK〗∶1 and 0.1〖DK〗∶1 respectively; the expression of Cdc25 in RNAi-allC cells was 8 times that of KAx-3 cells. The data suggested that once the expression of ATR had little change, Chk1 and Cdc25 expression changed greatly. Western blotting results were consistent with Q-PCR reports. The Chk1 protein contents were significantly less in mutant type RNAi-allC than that in KAx-3cells; the Cdc25 protein contents were higher in RNAi-allC cells. The above mentioned results suggest that ATR-Chk1-Cdc25 signaling pathway involved in the regulation of the G2/M phase in Dictyostelium discoideum.
Novel derivative of xanomeline, SBG-PK-014, increases the α-secretion of APPsw
WANG Dong, ZHOU Zong-li, GAO Hong, LEI Xiao-ping, DONG Su-zhen, HU Jin-feng
2014, (1): 123-132.
Abstract:
The activity of a novel derivative of xanomeline, SBG-PK-014, on muscarinic M1 mAChRs and the -secretion of human APP Swedish mutant (APPsw) was evaluated. The EC50 and maximum folds of activation (FAmax) were measured in a cell-based model. Mouse N2a cells over-expressing both APPsw and M1 mAChR gene were treated with SBG-PK-014 and xanomeline, respectively. Their secreation levels of sAPP were then measured using Western Blotting. The results showed that SBG-PK-014 had a similar EC50 to xanomeline (40.2 nmol/L vs. 28.4 nmol/L), but demonstrated a 3.5-fold FAmax, as compared to xanomeline. SBG-PK-014 promoted the -secretion of APPsw via the activation of M1 receptors. At the same dose of 0.1 mol/L and 1 mol/L, SBG-PK-014 exhibited significantly more potent activity. SBG-PK-014 activated M1 receptors more effectively than xanomeline, increased the -cut of APPsw as well as the secretion of neuroprotective sAPP, showed potential in modifying the A pathology of Alzheimers disease (AD), and is worth further development.
EcR-RNAi and azadirachtin treatments induced the abnormal proleg development in Spodoptera litura.
ZHAO Jin-cheng, WU Tian-min, LIU Li-hua, WANG Yang, HE Lin
2014, (1): 133-142.
Abstract:
Ecdysone is the insect molting hormone which induces a series of events critical for ecdysis, beginning with the formation of a complex between ecdysteroid receptor (EcR) and its partner protein, ultraspiracle (Usp). We cloned a 600~bp partial cDNAs encoding 200 amino acids EcR protein by degenerate primers from the common cutworm, \textit{Spodoptera litura}, a destructive agricultural pest insect in East Asia. We used this fragment to design the EcR-dsRNA to interfere the corresponding gene to analysis the change in different development stages. Using the Azadirachtin (Az) feeding the RNAi injected larvae to observe the development difference with normal control. Results indicated that the EcR RNAi interference the normal ecdysis and result in incomplete pupal molt. In the Az treatment after EcR RNAi injection, the larvae stunt growth and development program were disturbed and observed abnormal proleg phenotype. We deduced that Az and EcR RNAi maybe influence the key genes and inhibit the ecdysone cascade modulate pathway, which result in the disorder of tissue remodeling in molting.