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Mollisols are the most fertile, high-yielding soils in the world. During the past several decades, Mollisols have lost about 50% of their antecedent organic carbon (C) pool due to soil erosion, degradation, and other unsuitable human activities. Therefore, restoring soil organic C (SOC) to Mollisols via reasonable management is crucial to sustainable development and is important for environmental stability. However, the existing literature on SOC and soil quality has focused on one soil type or on a given region where Mollisols occur, and the degree of SOC depletion and stabilization in Mollisols have not been comprehensively evaluated. Overall, we propose to develop an optimum scheme for managing Mollisols, and we outline specific issues concerning SOC restoration and prevention of SOC depletion. In this review, we identify the uncertainties involved in analyses of SOC in Mollisols as related to management practices. According to the existing literature on SOC in Mollisols at the global scale, we analyzed the results of SOC depletion research to assess management practices and to estimate the C amount stabilized in Mollisols. The review shows that the SOC stocks in Mollisols in North America under cropped systems had 51 ± 4 (equiv. mass) Mg ha−1 in the top 30 cm soil layer. The SOC contents in Northeast China decreased from 52 to 24 g kg−1 (46%) after 150 years of cultivation management. All of the Mollisols regions in the world are facing the challenge of SOC loss, and this trend could have a negative influence on global climate change. Hence, it is very important to take proper measures to maintain and enhance organic C contents in Mollisols. We concluded that reasonable management practices, including no-tillage, manure and compost fertilization, crop straw returning, and mulching cultivation, are the recommended technologies. The C restoration in Mollisols is a truly win-win strategy for ensuring the security of food and soil resources while effectively mitigating global climate change. Thus, more attention should be given to protective management and land use for its impacts on SOC dynamics and soil properties in Mollisols regions.

Grain size and shape have significant effects on grain weight and is also an important breeding target due to market and industry requirements. In this study, the genetic loci associated with six grain morphology traits including thousand grain weight, grain length (GL), grain width, grain length to width ratio (GLWR), grain area (GA) and grain perimeter (GP) in a population of 300 Chinese wheat germplasm were investigated through genome wide association mapping. A total of 189 SNPs were significantly related to the six grain traits based on the BLUP data from three environments. Of these SNPs, 24 SNPs for GA, GL, GLWR, and GP were continuously detected under all three experiments. These SNPs were distributed on chromosome 2A, 2B, 2D, 4D, 5A, and 6D, respectively. Some SNPs such as Affx-88368872 on 2A, Affx-109472887 on 6D, and Affx-108968182, Affx-111286671, Affx-110418048, Affx-109838962, Affx-88484232 on 5A were associated with multiple traits. In addition, a chromosome region tagged by 11 SNPs (585,117,524–595,658,182 bp) on chromosome 2D had significant effects on GLWR. Several genes inside the regions on chromosome 5A and 2D may play crucial roles in determining seed size and weight. We will characterize the function of these genes in grain development in our future experiments. This study provides novel insights into the genetic basis of grain morphology traits in wheat.

This paper addresses the synchronization problem of Boolean networks. Based on the matrix expression of logic, solvability conditions and design procedures of the synchronization of Boolean networks with outputs are given for both open-loop and feedback control. Necessary and sufficient conditions on open-loop control are proposed first with a constructive design procedure. Then sufficient condition for the feedback control case is obtained, and corresponding design procedure is proposed with the help of algorithms to solve logic matrix equations. Numerical examples are also provided to illustrate the proposed control design.

In this paper, we propose a matrix-based approach for finite automata and then study the reachability conditions. Both the deterministic and nondeterministic automata are expressed in matrix forms, and the necessary and sufficient conditions on reachability are given using semitensor product of matrices. Our results show that the matrix expression provides an effective computational way for the reachability analysis of finite automata.

Schistosoma japonicum causes schistosomiasis in humans and livestock in the Asia-Pacific region. Knowledge of the genome of this parasite should improve understanding of schistosome-host interactions, biomedical aspects of schistosomiasis and invertebrate evolution. We assigned 43,707 expressed sequence tags (ESTs) derived from adult S. japonicum and their eggs to 13,131 gene clusters. Of these, 35% shared no similarity with known genes and 75% had not been reported previously in schistosomes. Notably, S. japonicum encoded mammalian-like receptors for insulin, progesterone, cytokines and neuropeptides, suggesting that host hormones, or endogenous parasite homologs, could orchestrate schistosome development and maturation and that schistosomes modulate anti-parasite immune responses through inhibitors, molecular mimicry and other evasion strategies.