Eigenvector-based analysis of cluster synchronization in general complex networks

While symmetry has been exploited to analyze synchronization patterns in complex networks, the identification of symmetries in large-size network remains as a challenge. We present in the present work a new method, namely the method of eigenvector-based analysis, to identify symmetries in general complex networks and, incorporating the method of eigenvalue analysis, investigate the formation and transition of synchronization patterns. The efficiency of the proposed method is validated by both artificial and empirical network models consisting of coupled chaotic oscillators. Furthermore, we generalize the method to networks of weighted couplings in which no strict symmetry exists but synchronization clusters are still well organized, with the predications agreeing with the results of direct simulations. Our study provides a new approach for identifying network symmetries, and paves a way to the investigation of synchronization patterns in large-size complex network.Comment: 5 figure

The miR167-OsARF12 module regulates grain filling and grain size downstream of miR159

Grain weight and quality are always determined by the grain filling. Plant miRNAs have drawn attention as key targets for regulating grain size and yield. Yet the mechanisms underlying the regulation of grain size are largely unclear due to the complex networks controlling this trait. Our earlier studies proved that the suppressed expression of miR167 (STTM/MIM167) substantially increased grain weight. In a field test, the increased yield up to 12.90%-21.94% due to the significantly enhanced grain filling rate. Biochemical and genetic analyses reveal the regulatory effects of miR159 on miR167 expression. Further analysis indicates that OsARF12 is the major mediator of miR167 in regulating rice grain filling. Expectedly, over expressing OsARF12 could resemble the phenotype of STTM/MIM167 plants with respect to grain weight and grain filling rate. Upon in-depth analysis, we found that OsARF12 activates OsCDKF;2 expressions by directly binding to the TGTCGG motif in the promoter region. Flow cytometric analysis in young panicles of plants overexpressing OsARF12 and cell number examination of cdkf;2 mutants verify that OsARF12 positively regulates grain filling and grain size by targeting OsCDKF;2. Moreover, RNA-seq result suggests that miR167-OsARF12 module is involved in the cell development process and hormone pathways. Additionally, plants overexpressing OsARF12 or cdkf;2 mutants present enhanced or reduced sensitivity to exogenous auxin and brassinosteroid (BR) treatments, confirming that OsCDKF;2 targeting by OsARF12 mediates auxin and BR signaling. Our results reveal that miR167-OsARF12 module works downstream of miR159 to regulate rice grain filling and grain size by OsCDKF;2 through controlling cell division and mediating auxin and BR signals

The Interaction between Auxin and Nitric Oxide Regulates Root Growth in Response to Iron Deficiency in Rice

Fe deficiency (-Fe) is a common abiotic stress that affects the root development of plants. Auxin and nitric oxide (NO) are key regulator of root growth under -Fe. However, the interactions between auxin and NO regulate root growth in response to Fe deficiency are complex and unclear. In this study, the indole-3-acetic acid (IAA) and NO levels in roots, and the responses of root growth in rice to different levels of Fe supply were investigated using wild type (WT), ospin1b and osnia2 mutants. -Fe promoted LR formation but inhibited seminal root elongation. IAA levels, [3H] IAA transport, and expression levels of PIN1a-c genes in roots were reduced under -Fe, suggesting that polar auxin transport from shoots to roots was decreased. Application of IAA to -Fe seedlings restored seminal root length, but not LR density, to levels similar to those under normal Fe (+Fe), and the seminal root length was shorter in two ospin1b mutants relative to WT under +Fe, but not under -Fe, confirming that auxin transport participates in -Fe-inhibited seminal root elongation. Moreover, -Fe-induced LR density and -Fe-inhibited seminal root elongation paralleled NO production in roots. Interestingly, similar NO accumulation and responses of LR density and root elongation were observed in osnia2 mutants compared to WT, and the higher expression of NOA gene under -Fe, suggesting that -Fe-induced NO was generated via the NO synthase-like pathway rather than the nitrate reductase pathway. However, IAA could restore the functions of NO in inhibiting seminal root elongation, but did not replace the role of NO-induced LR formation under -Fe. Overall, our findings suggested that NO functions downstream of auxin in regulating LR formation; NO-inhibited seminal root elongation by decreasing meristem activity in root tips under -Fe, with the involvement of auxin

Nitric Oxide Affects Rice Root Growth by Regulating Auxin Transport Under Nitrate Supply

Nitrogen (N) is a major essential nutrient for plant growth, and rice is an important food crop globally. Although ammonium (NH4+) is the main N source for rice, nitrate (NO3-) is also absorbed and utilized. Rice responds to NO3- supply by changing root morphology. However, the mechanisms of rice root growth and formation under NO3- supply are unclear. Nitric oxide (NO) and auxin are important regulators of root growth and development under NO3- supply. How the interactions between NO and auxin in regulating root growth in response to NO3- are unknown. In this study, the levels of indole-3-acetic acid (IAA) and NO in roots, and the responses of lateral roots (LRs) and seminal roots (SRs) to NH4+ and NO3-, were investigated using wild-type (WT) rice, as well as osnia2 and ospin1b mutants. NO3- supply promoted LR formation and SR elongation. The effects of NO donor and NO inhibitor/scavenger supply on NO levels and the root morphology of WT and nia2 mutants under NH4+ or NO3- suggest that NO3--induced NO is generated by the nitrate reductase (NR) pathway rather than the NO synthase (NOS)-like pathway. IAA levels, [3H] IAA transport, and PIN gene expression in roots were enhanced under NO3- relative to NH4+ supply. These results suggest that NO3- regulates auxin transport in roots. Application of SNP under NH4+ supply, or of cPTIO under NO3- supply, resulted in auxin levels in roots similar to those under NO3- and NH4+ supply, respectively. Compared to WT, the roots of the ospin1b mutant had lower auxin levels, fewer LRs, and shorter SRs. Thus, NO affects root growth by regulating auxin transport in response to NO3-. Overall, our findings suggest that NO3- influences LR formation and SR elongation by regulating auxin transport via a mechanism involving NO

Performance Analysis of Picking Path Strategies in Chevron Layout Warehouse

Order picking is the part with the highest proportion of operation cost and time in the warehouse. The characteristics of small-batch and multi-frequency current orders reduce the applicability of the traditional layout in the warehouse. Besides this, the improvement of the layout will also affect the picking path, such as the Chevron warehouse layout, and at present, there is a lack of research on order picking with multiple picking locations under non-traditional layouts. In order to minimize the order picking cost and time, and expand the research in this field, this paper selects the Chevron layout to design and describe the warehouse layout, constructs the picking walking distance model of Return-type, S-type and Mixed-type path strategies in the random storage Chevron layout warehouse, and uses the Cuckoo Search (CS) algorithm to solve the picking walking distance generated by the Mixed-type path. Compared with the existing single-command order picking research, the order picking problem of multi picking locations is more suitable for the reality of e-commerce warehouses. Moreover, numerical experiments are carried out on the above three path strategies to study the impact of different walking paths on the picking walking distance, and the performance of different path strategies is evaluated by comparing the order picking walking distance with the different number of locations to be picked. The results show that, among the three path strategies, the Mixed-type path strategy is better than the Return-type path strategy, and the average optimization proportion is higher than 20%. When the number of locations to be picked is less than 36, the Mixed-type path is better than the S-type path. With the increase of the number of locations to be picked, the Mixed-type path is gradually worse than the S-type path. When the number of locations to be picked is less than 5, the Return-type path is better than the S-type path. With the increase of the number of locations to be picked in the order, the S-type path is gradually better than the Return-type path

Presentation_1_Nitric Oxide Affects Rice Root Growth by Regulating Auxin Transport Under Nitrate Supply.pdf

<p>Nitrogen (N) is a major essential nutrient for plant growth, and rice is an important food crop globally. Although ammonium (NH₄⁺) is the main N source for rice, nitrate (NO₃^-) is also absorbed and utilized. Rice responds to NO₃^- supply by changing root morphology. However, the mechanisms of rice root growth and formation under NO₃^- supply are unclear. Nitric oxide (NO) and auxin are important regulators of root growth and development under NO₃^- supply. How the interactions between NO and auxin in regulating root growth in response to NO₃^- are unknown. In this study, the levels of indole-3-acetic acid (IAA) and NO in roots, and the responses of lateral roots (LRs) and seminal roots (SRs) to NH₄⁺ and NO₃^-, were investigated using wild-type (WT) rice, as well as osnia2 and ospin1b mutants. NO₃^- supply promoted LR formation and SR elongation. The effects of NO donor and NO inhibitor/scavenger supply on NO levels and the root morphology of WT and nia2 mutants under NH₄⁺ or NO₃^- suggest that NO₃^--induced NO is generated by the nitrate reductase (NR) pathway rather than the NO synthase (NOS)-like pathway. IAA levels, [³H] IAA transport, and PIN gene expression in roots were enhanced under NO₃^- relative to NH₄⁺ supply. These results suggest that NO₃^- regulates auxin transport in roots. Application of SNP under NH₄⁺ supply, or of cPTIO under NO₃^- supply, resulted in auxin levels in roots similar to those under NO₃^- and NH₄⁺ supply, respectively. Compared to WT, the roots of the ospin1b mutant had lower auxin levels, fewer LRs, and shorter SRs. Thus, NO affects root growth by regulating auxin transport in response to NO₃^-. Overall, our findings suggest that NO₃^- influences LR formation and SR elongation by regulating auxin transport via a mechanism involving NO.</p