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This paper studies the multi-asset pricing problem in the stock market with holding-based networks. We derive a linear noisy rational expectation equilibrium (LNREE) in the network, construct holding-based networks and test the LNREE's efficiency in generating predictive output validation. The results show that the LNREE fits the observed prices and returns of stocks quite well, especially for U.S. energy stocks. By changing the average risk aversion, the predictive performance of the model can be optimized. It provides a novel perspective for the empirical study on multi-asset pricing modeling. • We study multi-asset pricing model in the stock market with holding-based networks. • A linear noisy rational expectations equilibrium (LNREE) in the network is derived. • We analyze the co-holding behavior of shareholders from four energy indices. • LNREE performs well in the predictive output validation, especially for U.S. stocks. • Our model is more efficient in the forecasting process relative to the original one. [ABSTRACT FROM AUTHOR]

Abstract: As the origin center of apricots, China has the richest apricot germplasm resources. The establishment of core collections is very important for a better evaluation and utilization of apricot germplasm. In this study, 1501 apricot accessions from the initial collections in China were used to sample and establish a primary core collection. Data of 18 traits including both quantitative and qualitative were collected and used to design sampling strategy. The overall sampling strategy includes principles for grouping, sampling proportion within group and sampling method from each group. Three sampling proportions 5%, 10% and 15% were used in the study. Our results suggest that 10% was the best entire sampling ratio for primary core collection of apricots. With 10% entire sampling ratio, the optimal sampling strategy was to group samples based on their growing regions, in combination with logarithmic sampling proportion within each group. Using this sampling strategy, we have established a primary core collection with 150 accessions, and the primary core collection can well represent the genetic diversities of the entire collection. The genetic diversity of the apricot primary core collection was further analyzed using Simple Sequence Repeats (SSRs) molecular marker technique. A total of 22 polymorphic specific primers were developed and 196 alleles were detected. The average number of alleles in each locus was 8.9, suggesting that there were very rich genetic variances among the prime core collection. This also confirms that our primary core collection is a good representation of the genetic diversities of the whole collections at DNA level. [Copyright &y& Elsevier]

Abstract: In this paper, we model a new random stock price model for the stock markets based on the finite range contact process, which is a model for epidemic spreading that mimics the interplay of local infections and recovery of individuals, it is a member of a class of stochastic processes known as interacting particle systems. Then, we analyze the statistical behaviors of Shanghai Stock Exchange (SSE) Composite Index, Shenzhen Stock Exchange (SZSE) Composite Index, Dow Jones Industrial Average Index (DJIA), Nasdaq Composite Index (IXIC), the standard and Poor’s 500 Index (S&P500) and the simulative data derived from the finite range contact model by comparison. And six individual Chinese stocks from large-cap, mid-cap and small-cap categories are discussed. Furthermore, we investigate the long range correlations of the returns for these indices and the corresponding simulative data by applying the detrended fluctuation analysis. At last, the positive part of the probability distributions of the logarithmic returns for the actual data and the simulative data are studied by the q-Gaussian dynamic systems. The main objective of this work is to discuss the impact on the returns with the different range financial models. [Copyright &y& Elsevier]

Abstract: Proton pumps play an important role in the physiological activities of plants. Changes in membrane-associated H+- and Ca2+-ATPase activities in heat-shocked plants after heat acclimation (HA) or salicylic acid (SA) pre-treatment in annual young grape plants (Vitis vinifera L. cv. Jingxiu) were investigated. ATPase activity was assayed through biochemical analysis in which two-phase partitioning was used to purify plasma membranes and cerium trichloride was precipitated with an electromicroscopic cytochemical method. The plasmalemma H+- and Ca2+-ATPase activities were higher in HA- or SA-pre-treated plants than in controls. The stability of H+- and Ca2+-ATPase activities in pre-treated plants always remained at higher levels during subsequent heat shock treatment, which was consistent with the observations made using an electromicroscope. A number of cerium phosphate grains representing enzyme activity in HA- or SA-pre-treated plants were observed 6h following heat shock, whereas no grains were found in control plants under the same conditions. These results suggest that the changes in the activities of plasma membrane H+- and Ca2+-ATPase contributed to the thermotolerance induced by either HA or SA pre-treatment in young grape plants and the two pre-treatments may have had the some same regulatory mechanism. [Copyright &y& Elsevier]

Abstract: Grape berries (Vitis vinifera cv. Jingxiu) were pretreated for 10h in air either at 38°C (heat pretreatment) or at 25°C (control) and then transferred to −2°C for 0, 3, 6,12, 24, 48 and 72h, respectively. Compared with the control without heat pretreatment, membrane permeability and malondialdehyde (MDA) contents were reduced and the activities of peroxidase, superoxide dismutase (SOD) and catalase increased in the heat-pretreated berries under chilling stress. Heat pretreatment could protect the ultrastructure of the pericarp cells against subsequent chilling injury. In the control berries, the ultrastructure of pericarp cells was significantly damaged under chilling stress, with disordered stroma lamellae in the chloroplast or plastid, an indistinct nuclear membrane, looser cell walls, disorganized or absent middle lamella and a less identifiable nuclear membrane. After 72h of chilling stress, the cellular organelles could no longer be identified. These results offered cytological evidence that berries subjected to a mild heat stress could acquire tolerance to subsequent lethal low temperatures. The heat pretreatment also induced expression of Hsp70 transcripts. The results suggest that cross-adaptation could be induced in grape berries and the fruit could adapt, at least partly, to low temperature through heat pretreatment-induced tolerance. [Copyright &y& Elsevier]

• A new stock selection algorithm is proposed. • Grey wolf optimizer is innovatively hybridized with support vector regression. • The performance of hybridizing different meta-heuristics is compared. • The new algorithm can achieve excess returns in American and Chinese markets. • The effectiveness and superiority of the new algorithm are empirically examined. Artificial intelligence remarkably facilitates quantitative investment. A latest intelligent search algorithm, grey wolf optimizer, is well integrated with support vector regression machine to obtain the optimal portfolio. The performance of the hybrid algorithm is empirically investigated through transactional and financial data from stock markets of America and China. The experimental results indicate that (i) the proposed algorithm is able to stably achieve excess returns; (ii) compared with genetic algorithm, particle swarm optimization, gravitational search algorithm and harmony search, the enhanced grey wolf optimizer significantly boots the predictive performance of support vector regression machine; (iii) the proposed algorithm can achieve the better profitability and the higher reliability in Chinese A-share market. [ABSTRACT FROM AUTHOR]

Highlights: [•] We determine distributions of sugars and acids with compartmental analysis method. [•] We examine the alteration of sugars and acids in vacuole, cytoplasm and free space. [•] Membrane permeability to sugars and acids are measured at different growing stages. [•] We analyze distributions of sweetness and sour in different compartments of cells. [ABSTRACT FROM AUTHOR]