Controlling Chaos in a Neural Network Based on the Phase Space Constraint

The chaotic neural network constructed with chaotic neurons exhibits very rich dynamic behaviors and has a nonperiodic associative memory. In the chaotic neural network, however, it is dicult to distinguish the stored patters from others, because the states of output of the network are in chaos. In order to apply the nonperiodic associative memory into information search and pattern identication, etc, it is necessary to control chaos in this chaotic neural network. In this paper, the phase space constraint method focused on the chaotic neural network is proposed. By analyzing the orbital of the network in phase space, we chose a part of states to be disturbed. In this way, the evolutional spaces of the strange attractors are constrained. The computer simulation proves that the chaos in the chaotic neural network can be controlled with above method and the network can converge in one of its stored patterns or their reverses which has the smallest Hamming distance with the initial state of the network. The work claries the application prospect of the associative dynamics of the chaotic neural network

1-(4-Cyano­benz­yl)-4-methyl­pyridinium bromide

In the title compound, C14H13N2 +·Br−, the 1-(4-cyano­benz­yl)-4-methyl­pyridinium cation has a Λ-shaped conformation, and the dihedral angle between the benzene and pyridinium rings is 75.8 (2)°. In the crystal, two cations form a dimer through π–π inter­actions between pyridine rings [the centroid–centroid distance is 3.685 (1) Å]

Poly[aqua[μ2-1,2-bis­(imidazol-1-yl­methyl)benzene-κ2 N 3:N 3′](μ2-5-bromo­benzene-1,3-dicarboxyl­ato-κ3 O 1,O 1′:O 3)nickel(II)]

In the two-dimensional title coordination polymer, [Ni(C8H3BrO4)(C14H14N4)(H2O)]n, the NiII atom adopts a distorted octa­hedral geometry, being ligated by three O atoms from two different 5-bromo­benzene-1,3-dicarboxyl­ate ligands, two N atoms from two 1,2-bis­(imidazol-1-ylmeth­yl)benzene ligands and one coordinated water mol­ecule. The Ni atoms are bridged by the 5-bromo­benzene-1,3-dicarboxyl­ate ligands, forming chains, which are further linked by 1,2-bis­(imidazol-1-ylmeth­yl)benzene, generating a layer structure parallel to (001)

Studies on the soybean aphid, Aphid glycines Matsumura

The soybean aphid is widely distributed among all major soybean growing regions in China. It causes severe damage in Jilin, Liaoning, and Helongjiang Provinces, and part of the inner Mongolian autonomous region, and those areas are often called aphid-stricken areas. Its hosts include wild soybean (Glycine benth forma lanceolate Makino), buckthorn (Rhamnus davuricus) as well as soybean. Results of field investigation and inoculation experiments confirmed that the widely distributed buckthorn in the Northern Provinces is the over-wintering host for soybean aphids. According to the life cycle of aphids and their characteristic damage to soybeans, three different periods of impact can be recognized: 1) starting from seedling stage to blooming stage (mid-July), the aphid population reaches its peak point. About 50-70% of the whole aphid population colonizes on the tender leaves and twigs on top of the soy plants. The soybean damage caused during this period has the worst impact on the plants. 2) During the third ten days of July when the soybean plants cease to grow, aphids then migrate from the top leaves and twigs to the middle or lower ones and feed on the underside of the leaves. At the same time, the young nymphs appear. The aphid population grows slowly, and their damage to soybean plants is at a low tide. 3) From late August -- the late pod bearing period -- to early September -- the yellow maturing period -- aphids start their late multiplying stage. In late Fall, aphids migrate back to buckthorn, their overwintering host, and oviposit overwintering eggs after mating. During Fall, the male aphids and the ovipositional female aphids are living on different hosts. Gynoparae live on buckthorn, and the male aphids live on soybean. Aphids reproduce 15 generations a year on soybean. After analyzing the life cycle of aphids, their growth pattern in the field, as well as the meteorological data in recent years, we came to preliminary results about the growth and decline pattern of aphids and their affecting factors: 1) the more the overwintering eggs and aphids numbers were at the seedling stage, the more severe their impact on seedlings; 2) Average temperatures between 22-25 °C and relative humidity below 78% from late June to early July greatly favored the growth and reproduction of aphids. Even if the original aphid population is small, severe aphid epidemics still could occur during the blooming period in July because aphids reproduced very quickly under those favorable weather conditions; 3) As the growth points ceased growing in late July and the nutrient condition deteriorated, the aphid population declined. In summary, we may make long- or short-term predictions of aphid epidemics based on the number of overwintering eggs, meteorological data, and current and past aphid information. Based on the results of several years’ laboratory and field experiments, the following aphid control measures achieved very good results: 0.5% lindane (benzene hexachloride, or BHC), 1 to 300-400 diluted 6% BHC wettable powder, 1 to 15000 diluted E605 (parathion), 1 to 100 diluted tobacco leaf solution, and seed coating with 20% BHC. Among these methods, 0.5% BHC powder and seed coating with 0.7% of 20% BHC have been widely used in agricultural practice.Originating text in Chinese.Citation: Wang, Cheng Lun, Xiang, Liang Ying, Zhang, Guang Xue, Zhu, Hong Fu. (1962). Studies on the soybean aphid, Aphid glycines Matsumura. Acta Entomologica Sinica, 11, 31-44

2,5-Dibromo­terephthalic acid dihydrate

The asymmetric unit of the title compound, C8H4Br2O4·2H2O, contains one half-mol­ecule of 2,5-dibromo­terephthalic acid (DBTA) and one water mol­ecule. The DBTA mol­ecule is centrosymmetric. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules, forming a three-dimensional framework

Influence of acupuncture on cognitive function and markers of oxidative DNA damage in patients with vascular dementia

AbstractObjectiveTo test the influence of acupuncture on cognitive function and a marker of oxidative DNA damage in patients with vascular dementia (VD).MethodsSixteen VD patients were evaluated before and after acupuncture, using the Folstein Mini-Mental State Examination-Revised (MMSE-R) to assess cognitive function, and the ADL-R scale to assess independence in activities of daily living (ADL). Life quality was evaluated using the DEMQOL (Dementia quality of life questionnaire) questionnaire, and syndromes and expression of vascular dementia were evaluated with the Scale for the Differentiation of Syndromes of Vascular Dementia (SDSVD). In addition, the urine concentration of 8-hydroxy-2′-deoxyguanosine (8-OHdG) —a marker of oxidative damage—was quantified with enzyme-linked immunosorbent assay.ResultsThe MMSE-R and DEMQOL scores were higher after acupuncture than before (P<0.05), while there were no obvious differences in the ADL-R or SDSVD scores (P>0.05). The 8-OHdG content in urine significantly decreased after acupuncture (P<0.05).ConclusionAcupuncture reduces the levels of 8-OHdG and improves cognitive function and quality of life in VD patients, suggesting that acupuncture is beneficial at least in part by preventing oxidative damage