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Spatial and temporal resource allocations within inflorescences have been well-studied in many plants based on flowering sequence or floral position. However, there had been few attempts to investigate architectural effects and resource competition in species where the blooming pattern does not follow a linear positional pattern within the inflorescence. Moreover, most flowering plants show female-biased sex allocation in early or basal flowers, but it is unclear in species with inherent and changeless ovule production.We investigated intra-inflorescence variation in reproductive traits of Salvia przewalskii, a perennial herb with 4-ouvle ovary flowers and flowering sequence-floral position decoupled inflorescences. To detect the effects of resource competition and architectural effects on reproductive success, we manipulated inflorescence (removed floral buds by position and flowering sequence) and pollination (opened and supplemented pollination).Pollen production and dry mass deceased from bottom to top flowers but did not significantly differ following flowering sequence, resulting in male-biased sex allocation in basal flowers. The seed production, fruit set, and bud development exhibited significant declining trends from proximal to distal positions regardless of the thinning and pollen treatments. Meanwhile, the seed production, fruit set, and bud development success did not significant differ when thinning was conducted according to flowering sequence.Architectural effects plays a crucial role in resource allocation within decoupled flowering inflorescences. Moreover, our results highlighted that inherent floral traits such as changeless ovule production, may modify architectural effects on sex allocation.

Techniques of reduced-representation sequencing (RRS) have revolutionized ecological and evolutionary genomics studies. Precise establishment of orthologs is a critical challenge for RRS, especially when a reference genome is absent. The proportion of shared heterozygous sites across samples is an alternative criterion for filtering paralogs. In the prevailing pipeline for variant calling of RRS data – PYRAD/IPYRAD, maxSH is an often overlooked parameter with implications to detecting and filtering paralogs according to shared heterozygosity. Using empirical genotyping by sequencing data of two primroses (Primula alpicola Stapf and Primula florindae Ward) and their putative hybrids, and extra data sets of Californian golden cup oaks, we explore the impact of maxSH on filtering paralogs and further downstream analyses. Our study sheds light on the simultaneous validity and risk of filtering paralogs using maxSH, and its significant effects on downstream analyses of outlier detection, population assignment, and demographic modeling, emphasizing the importance of attention to detail during bioinformatic processes. The mutual confirmation between results of population assignment and demographic modeling in this study suggested maxSH = 0.10 has a potentially excessive and asymmetrical effect on the removal of truly shared heterozygous sites as paralogs. These results indicate that hybridization origin hypotheses of putative hybrids represented by results with maxSH = 0.25 and 0.50 are more credible. In conclusion, we revealed the critical hazard of paralogs filtration according to sharing heterozygosity at first, so that we propose to use specific protocols, rather than maxSH, to filter potential paralogs for closely related lineages.

Aims Identifying the potential role of vegetation context (defined as the density, species identity/diversity and height of co-occurring plants) in modifying selection on floral traits is a critical step for clarifying and predicting the floral evolutionary trajectory in complex co-flowering species competition environments. It is also helpful to understand the variation in pollinator-mediated selection. Methods We experimentally reduced vegetation height around individual plants of Spiranthes sinensis (a bumblebee-pollinated perennial orchid herb) and estimated how vegetation context modified selection on four floral traits (flowering start, plant height, corolla size and number of flowers) through female function and pollen removal over two continuous years. We randomly selected independent plants in each year. Important Findings We demonstrated that vegetation context modified selection for earlier flowering start and shorter plant height of S. sinensis. The strength of selection differed between years. In addition, selection was stronger through female function than through pollen removal. Our findings indicate the potential role of vegetation context in shaping the differentiation and diversification of flowers in angiosperms.

This study aims to investigate how various forms of social control, namely selective incentive and behavioral conformity, collectively rationalize participation in collective action, through indirect network connections. To address it, we use a public game model and analyze the equilibrium conditions of the emergence of collective action on centralized, star-shaped networks and on decentralized, loop-shaped networks. The results show that social control is effective in motivating contribution towards a public good; however, the effect is highly dependent on the ratio of the benefits derived from selective incentive versus behavioral conformity as well as on the structure of social networks. Moreover, we find that indirect network connections can be an important route through which social control can improve the emergence of collective action. These findings have important implications for collective action theory and for intervention in collective actions.

Sexual interference between male and female function in hermaphrodite plants is reduced by protandry. In environments with insufficient pollinator service, prolongation of male function owing to limited pollen removal could restrict the duration of female function and lower seed production. We provide evidence that this form of sexual conflict has played a role in the spread of females in gynodioecious populations of Cyananthus delavayi in the pollen-limited environments in which this subalpine species occurs. Using field experiments involving artificial pollen removal from the strongly protandrous flowers of hermaphrodites, we demonstrated a trade-off between male- and female-phase duration with no influence on overall floral longevity. Pollen removal at the beginning of anthesis resulted in hermaphrodite seed production matching that of females. In contrast, restricted pollen removal increased the duration of male function at the expense of female function lowering maternal fertility compared to females. This pattern was evident in five populations with females experiencing a twofold average seed fertility advantage compared to hermaphrodites. Gynodioecy often appears to evolve from protandrous ancestors and pollen limitation is widespread in flowering plants suggesting that sexual conflict may play an unappreciated role in the evolution of this form of sexual dimorphism.

Aims As one of the most important agents driving floral evolution, pollinators shape the diversity of flowers in angiosperms. However, most previous studies have only quantified pollinators driving the evolution of a single floral trait, and experimental estimates of the potential role of pollinators in shaping the evolution of floral trait associations are relatively rare. Methods We experimentally identified and estimated the pollinator-mediated directional and correlational selection on single floral traits and trait combinations across 2 years in an orchid species, Spiranthes sinensis. Important Findings Pollinators mediated directional selection for an earlier flowering start date and larger corolla size. Pollinators mediated positive correlational selection on the combinations of floral display traits and negative correlational selection on the combinations of flowering phenology and floral display traits. In addition, the strength of selection differed over time. Our results highlight the potential role of pollinators in driving the evolution of floral trait combinations and suggest that it is necessary to consider floral character functional associations when seeking to understand and predict the evolutionary trajectory of flowers in angiosperms.

AIM: Regional disjunction in mountainous regions is ubiquitous and is closely associated with the evolution of mountain biodiversity. However, the mechanisms of maintaining regional disjunction are often ignored, especially regarding the role of ecological barriers. The aim of this study is to test whether an ecological barrier maintains the regional disjunction of Roscoea between the Himalayas (HIM) and the Hengduan Mountains/Yun‐Gui Plateau (HMY). LOCATION: The Himalayas and the Hengduan Mountains/Yun‐Gui Plateau, Asia. TAXON: Monocot:Zingiberales:Zingiberaceae:Roscoea. METHODS: Occurrence data from Roscoea were collected from public databases and field investigations. Environmental niche modelling (ENM) was used to predict the potential distribution of Roscoea during the Last Interglacial (LIG), the Last Glacial Maximum (LGM), the present and the future. An environmental variable difference test, principal component analysis (PCA), discriminant function analysis (DFA) and niche identity test were employed to qualify and quantify the contributions of environmental factors to ecological divergence based on 7 and 26 environmental variables. RESULTS: Environmental niche modelling predicted an ecological gap of Roscoea between the HIM and the HMY from the LIG into the future, excluding the LGM. Statistically significant differences were detected in eight unique environmental variables across the Gap, which was mostly related to low temperatures and high moisture levels. The PCA, DFA and niche identity test suggested larger ecological separations among the Gap, the HIM and the HMY based on 26 environmental variables than based on seven variables. MAIN CONCLUSIONS: All clues point to an ecological barrier that has been maintaining the regional disjunction of Roscoea. This ecological barrier is predicted to be stable under future climate change and may reflect long‐term ecological divergence shaped by the adaptation of Roscoea to divergent habitats. Our study highlights that the effects of specific environmental variables, with possible interactions among multiple ecological factors, being closely related to the ecological barrier.

The trait-fitness relationship influences the strength and direction of floral evolution. To fully understand and predict the evolutionary trajectories of floral traits, it is critical to disentangle the direct and indirect effects of floral traits on plant fitness in natural populations. We experimentally quantified phenotypic selection on floral traits through female fitness and estimated the casual effects of nectar robbing with different nectar robbing intensities on trait-fitness relationships in both the L- (long-style and short-anther phenotype) and S-morph (short-style and long-anther phenotype) flowers among Primula secundiflora populations. A larger number of flowers and wider corolla tubes had both direct and indirect positive effects on female fitness in the P. secundiflora populations. The indirect effects of these two traits on female fitness were mediated by nectar robbers. The indirect effect of the number of flowers on female fitness increased with increasing nectar robbing intensity. In most populations, the direct and/or indirect effects of floral traits on female fitness were stronger in the S-morph flowers than in the L-morph flowers. In addition, nectar robbers had a direct positive effect on female fitness, but this effect varied between the L- and S-morph flowers. These results show the potential role of nectar robbers in influencing the trait-fitness relationships in this primrose species.

Reducing geitonogamy (pollen transfer among flowers within the same plant) has been suggested as a major selective force for plants with multiple flowers. The occurrence of geitonogamy is generally different among flowers within inflorescences; however, no researchers have examined whether plants enlarge their display size without increasing the possibility of geitonogamy by presenting more flowers at positions where they are less likely to be geitonogamously pollinated. We observed that bumblebee pollinators foraged upward within the tower‐shaped inflorescences of protandrous Megacodon stylophorus (C. B. Clarke) Harry Sm. Because M. stylophorus did not strictly bloom bottom‐up, there were substantial frequencies of geitonogamous pollination resulting from upward and horizontal pollen transfer. Although there was a strong correlation between total numbers of flowers plants produced and numbers of flowers presented on single days, proportions of flowers possibly geitonogamously pollinated were weakly correlated with total numbers of flowers. This might have been because plants with more resources enlarged their display size by producing more flowers on lower floors where flowers had a low probability of being geitonogamously pollinated. This study shows that the tower‐shaped inflorescences of M. stylophorus enlarge their size without more cost of geitonogamous mating, suggesting that geitonogamy acts as an important selective agent in the evolution of inflorescence architectures.

The genus Roscoea, a Himalayan endemic and only alpine member of the predominately tropical family Zingiberaceae, is well-known for possessing elaborate floral traits commonly associated with biotic pollination, and particularly with long-tongued fly pollination. These traits include showy, easily detectable flowers with wide labellum serving as a landing platform for floral visitors, absence of discernible fragrance, presence of nectar as a reward, elongated reproductive organs situated away from the nectar source, and long corolla tube that is compatible with the tongue length of long-tongued insects (Goldblatt and Manning 2000, Cowley 2007).

Pancreatic cancer (PC) is the most lethal malignant tumor, with average survival period of about 10 months. C-X-C ligand 5 (CXCL5), an important chemokine for immune cell accumulation in tumor tissues, has been reported to be involved in a variety of human cancers. However, the exact role of CXCL5 in PC progression has not been well defined.The expression of CXCL5 in PC was analyzed based on online databases and clinical specimens immunohistochemical staining, and Western blotting of CXCL5 in PC cell lines and patient samples. The correlation between CXCL5 expression and prognosis in PC was explored. The role of CXCL5 in PC was investigated through in vitro and in vivo experiments.The expression of CXCL5 was significantly increased in PC tissues compared with that in pancreas tissues, and CXCL5 high expression predicts poor prognosis in PC patients. Further analyses demonstrated that overexpression of CXCL5 in PC cells was positively related to higher proliferation rate, higher migration ability, and higher EMT markers including SNAI2 and TWIST1 of tumor cells in vitro. Consistently, the knockdown of CXCL5 in PC cells harmed the proliferation rate, migration ability, and expression of EMT indexes of tumor cells in vitro. Importantly, knockdown of CXCL5 inhibited the growth of xenograft tumors in vivo.CXCL5 high expression predicts poor prognosis in PC patients. CXCL5 promotes PC cell growth and EMT process. Inhibition of CXCL5 may be a potential therapeutic approach for PC.

The Himalayas with dramatic elevation gradient is one of the global biodiversity hotspots. Although origin of biodiversity of the Himalayas is of great concern, the speciation process within the Himalayas is poorly known. Roscoea within the Himalayas serve as a good model system to test the speciation process along an elevation gradient. 32,375 unlinked SNPs were used to reconstruct phylogenetic relationships and introgression analyses in D-statistics and Fastsimicoal2. Species distribution modeling (SDM) was used to simulate habitat shift of Roscoea species during climate changes. Phylogeny suggested that the speciation order, except R. capitata, was from highland to lowland. D-statistics analyses suggested significant bidirectional ancient introgression between elevation-neighboring clades but no introgression between R. capitata and othern clades and no introgression among extant species. Fastsimicoal2 suggested interspecific introgressions were asymmetric. SDM predicted that habitats of Roscoea shifted to low elevation during cooling age. These results suggested that the sudden uplift of the Himalayas likely promoted speciation by vicariance, and climate cooling drove species divergence towards lower elevation. This study provides explanations for the origin of biodiversity within the Himalayas, and an insight to understand speciation along elevation in the mountainous regions.

Techniques of reduced-representation sequencing (RRS) have revolutionized ecological and evolutionary genomics studies, especially favoring species without reference genome. But it is a great challenge for RRS data to precisely establish homologous loci, which is strongly associated with accuracy of downstream analyses and reliability of biological inferences. maxSH is an overlooked parameter with respect to detecting paralogs, belonging to PYRAD/IPYRAD──a prevailing pipeline for genotyping RADseq and GBS data. Using GBS data of two primroses (Primula alpicola Stapf and P. florindae Ward) and their putative hybrids, as empirical study, we explore the efficiency of maxSH on filtering paralogs and its impact on downstream analyses. At the same time, we try to assess if putative hybrids are truly speciated from hybridization. Our study sheds light on the efficiency of maxSH on filtering paralogs, and significant effects of maxSH, together with clustering threshold and missing data, on downstream analyses of outlier detection, population assignment, and demographic modelling, emphasizing the significance of carefully coping with bioinformatics process. On the other hand, although putative hybrids exhibit a genetic mixture of P. alpicola and P. florindae according to most STRUCTURE and PCA results, we cannot clearly draw a conclusion on the origin of putative hybrids due to conflicting demographic scenarios mainly resulted from altering maxSH value among nine chosen datasets. However, gene flow patterns of most optimal models from multiple maxSH values collectively indicate incomplete reproductive isolation between putative hybrids and two primroses, and the existence of indirect introgression between P. alpicola and P. florindae.

Plant populations at high elevation face extreme climatic conditions and resource limitations. The existence of distylous species at different elevations can help us investigate their adaptation to high altitudes, the evolution of their morphological characteristics, as well as their responses to limited resources. Here, 17 populations of Primula nivalis at different elevations were evaluated regarding variations in plant morphological characteristics, biomass allocation, and morphological plasticity in a heterogeneous environment. Our results demonstrate that heterogeneous environments can affect plant morphological characteristics and resource allocation in each sexual morph of these plants. Moreover, environmental variations reduced morphological plasticity in the two plant morphs, and the plasticity of long style (LS) plants was greater than that of short style (SS) plants. There were significant negative correlations between morphological characteristics and elevation, rainfall, temperature, and sunshine, and these are the main variables that affect morphological characteristics and resource allocation of both morphs of P. nivalis plants in heterogeneous environments. The morphological characteristics of P. nivalis plants transplanted from high to lower elevations were not significantly different in either population. LS plants had greater morphological plasticity and adaptability in heterogeneous environments than SS plants. Elevational gradients and heterogeneous environments differentiated both morphs of P. nivalis plants with regards to morphology as well as adaptations. LS plants showed a higher level of adaptability than SS plants. Keywords: Biomass allocation, Plant sexual morph, Morphological characteristics, Adaptation

Floral visitor assemblages within plant populations are usually composed of different visitors, and the relative abundance of these visitors also varies. Therefore, identifying the relative strength of these floral visitors driving floral evolution within the population is an important step in predicting the evolutionary trajectory of floral traits. Using supplemental hand pollination and nectar-robbing exclusion treatments, we experimentally identified the relative strengths of legitimate pollinators (that visit flowers through the corolla tube entrance) and nectar robbers (that visit flowers by biting a hole in the corolla tube or using an existing hole) driving floral evolution within the Primula secundiflora population. We also estimated legitimate pollinator- and nectar robber-mediated selection separately for pin and thrum flowers. Both legitimate pollinators and nectar robbers mediated selection on pollination efficiency traits in P. secundiflora population. Legitimate pollinators mediated selection for wider corolla tubes, whereas nectar robbers mediated selection for longer corolla tubes. In addition, nectar robber-mediated selection on corolla tube length marginally varied between the pin and thrum flowers. Nectar robber mediated selection for longer corolla tube length in the pin flowers not in the thrum flowers. These results indicate that legitimate pollinators and nectar robbers within a population can drive differential evolutionary trajectories of floral traits.

Multiple barriers may contribute to reproductive isolation between closely related species. Understanding the relative strength of these barriers can illuminate the ecological factors that currently maintain species integrity and how these factors originally promoted speciation. Two Himalayan alpine gingers, Roscoea purpurea and R. tumjensis, occur sympatrically in central Nepal and have such similar morphology that it is not clear whether or how they maintain a distinct identity. Our quantitative measurements of the components of reproductive isolation show that they are, in fact, completely isolated by a combination of phenological displacement of flowering, earlier for R. tumjensis and later for R. purpurea, and complete fidelity of visitation by different pollinator species, bumblebees for R. tumjensis and a long-tongued fly for R. purpurea. Furthermore, the nectar of R. tumjensis flowers is available to the shorter tongued bumblebees while R. purpurea nectar is less accessible, requiring deep probing from long-tongued flies. Although flowering phenology is a strong current barrier that seemingly obviates any need for pollinator discrimination, this current pattern need not reflect selective forces occurring at the initial divergence of R. tumjensis. There has been considerable pollinator switching during the radiation of the Himalayan Roscoea, and the association of flowering time with type of pollinator in these sympatric species may have originated among the earliest or latest flowering individuals or populations of an ancestor to exploit either bumblebee activity early in the breeding season or long-tongued fly abundance later in the season. These two sympatric Roscoea species add to accumulating evidence of the primacy of prezygotic pollination traits in speciation among angiosperms even in the absence of postzygotic incompatibility.

The attitude and structural vibration of tethered solar power satellite were studied considering solar radiation pressure. Firstly, the simplified model of tethered solar power satellite was established. The solar panel was modeled as an Euler-Bernoulli Beam, the bus was modeled as a particle, and the tethers were modeled as massless springs. The equations of motion were derived based on absolute nodal coordinate formulation and Hamilton’s principle. Then, Symplectic Runge-Kutta method was adopted to solve the differential equations. The proposed model and numerical algorithm were validated through a numerical example. Finally, numerical simulations were carried out. Simulation results showed that solar radiation pressure as well as structural vibration cause small fluctuation of the attitude angle. Moreover, the effect of solar radiation pressure on structural vibration can be neglected.

About 20% of angiosperms employ self-fertilization as their main mating strategy. In this study, we aimed to examine how the selfing timing correlated with floral traits in three Gentianopsis species in which autonomous selfing is achieved through filament elongation. Although the three Gentianopsis species exhibit no significant variation in their capacity for autonomous selfing, flowers of G. grandis last longer, are larger and have a higher corolla biomass, P/O ratios and male biomass allocation than those of G. paludosa, and especially those of G. contorta. Autonomous selfing occurs in the early floral life of G. paludosa and G. contorta and in the later floral life of G. grandis. Seed production mainly results from autonomous selfing in G. paludosa and G. contorta; however, G. grandis could be more described as having a mixed mating system. We suggest that autonomous selfing in later floral life increases the chance of cross-pollination prior to this, while autonomous selfing in early floral life offers a selective advantage to plants by reducing the resource investment in traits that may increase pollinator attraction and visitation.

Natural hybridization frequently occurs in plants and can facilitate gene flow between species, possibly resulting in species refusion. However, various reproductive barriers block the formation of hybrids and maintain species integrity. Here, we conducted a field survey to examine natural hybridization and reproductive isolation (RI) between sympatric populations of Primula secundiflora and P. poissonii using ten nuclear simple sequence repeat (SSR) loci. Although introgressive hybridization occurred, species boundaries between P. secundiflora and P. poissonii were maintained through nearly complete reproductive isolation. These interfertile species provide an excellent model for studying the RI mechanisms and evolutionary forces that maintain species boundaries.

There is discussion over whether pollen limitation exerts selection on floral traits to increase floral display or selects for traits that promote autonomous self‐fertilization. Some studies have indicated that pollen limitation does not mediate selection on traits associated with either pollinator attraction or self‐fertilization. Primula tibetica is an inconspicuous cross‐fertilized plant that may suffer from pollen limitation. We conducted a selection analysis on P. tibetica to investigate whether pollen limitation results in selection for an increased floral display in case the evolution of autonomous self‐fertilization has been difficult for this plant. The self‐ and intra‐morph incompatibility features, the capacity for autonomous self‐fertilization, and the magnitude of pollen limitation were examined through hand‐pollination experiments. In 2016, we applied selection analysis on the flowering time, corolla width, stalk height, flower tube length, and flower number in P. tibetica by tagging 76 open‐pollinated plants and 37 hand‐pollinated plants in the field. Our results demonstrated that P. tibetica was strictly self‐ and intra‐morph incompatible. Moreover, the study population underwent severe pollen limitation during the 2016 flowering season. The selection gradients were found to be significantly positive for flowering time, flower number, and corolla width, and marginally significant for the stalk height. Pollinator‐mediated selection was found to be significant on the flower number and corolla width, and marginally significant on stalk height. Our results indicate that the increased floral display may be a vital strategy for small distylous species that have faced difficulty in evolving autonomous self‐fertilization.

Speciation, the evolutionary process forming new species, is a key mode generating biodiversity on the Earth. In this study, we produced a species-level phylogeny of Roscoea using one nuclear ribosomal and two chloroplast DNA fragments based on Bayesian inference and maximum likelihood. We then explored the possible speciation processes using the species-level phylogeny and the heterozygous sites in the nuclear DNA. The incongruence between nuclear and chloroplast phylogenies, and several heterozygous sites in the nuclear DNA, suggested that R. auriculata might have a hybrid origin with R. purpurea and R. alpina being two possible parental progenitors; however, one alternative possibility through incomplete lineage sorting cannot be ruled out. In addition, R. kunmingensis likely originated from R. tibetica Batalin through the process of “budding speciation”. These results provided a valuable framework to draw testable hypotheses for future in-depth comparative studies to further our understanding of the underpinning speciation and adaptation mechanisms that contribute to ultrahigh biodiversity in the Himalayas and the Hengduan Mountains.

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Floral organs are widely believed to enhance the pollination and reproductive success of angiosperms. However, the functional implication of some floral structures is still unknown. In this study, we explored the functional role of staminal appendages on male and female reproductive success of Himalayan Roscoea spp. and tested if their function differed between species with biotic pollination and autonomous selfing. Phenotypic manipulation is a powerful approach to test the functional effect of a particular trait on plant fitness. We compared various proxies of pollination success between intact flowers and flowers with manually excised staminal appendages. We found that the rate of visitation did not differ between intact and manipulated flowers. Our results revealed that in outcrossing Roscoea spp., the staminal appendages act as triggering devices to facilitate pollen release and deposition and also to manipulate the foraging position of pollinators to ensure both male and female reproductive success. In contrast, in autonomously selfing Roscoea spp., the removal of staminal appendages did not affect any aspect of pollination processes. Our results suggest that the staminal appendages are an integral component of outcrossing in Roscoea spp. and are maintained by selection pressure through both male and female reproductive success. This study provides important insights on how variation in breeding systems can provoke changes in the structure and function of floral organs among congeners.

Aim Ecological differentiation of closely related species has attracted wide attention to explore its evolutionary significance in speciation. In particular, the prevalence of ecological speciation of sister species driven by Quaternary climate changes is debated. Here, we used two parapatric sister species, Roscoea humeana and R. cautleoides, to test whether ecological speciation was associated with Quaternary climate changes in these taxa. Location Hengduan-Mountain Region (HMR), south-west of China. Methods Nuclear ribosomal (ITS) and chloroplast DNA (cpDNA: psbA–trnH and trnL–trnF) were sequenced from 200 individuals. Gene genealogies were reconstructed using network, Bayesian inference and maximum likelihood methods. Interspecific divergence times were estimated with an isolation with migration model. Suitable habitats for each species were estimated with ecological niche modelling using Maxent and BIOCLIM. Niche overlap and niche divergence were tested using Schoener's D and Warren's I. Principal components analysis (PCA), multivariate analysis of variance (MANOVA) and discriminant function analysis (DFA) were also used to test ecological differentiation. Results Gene genealogies indicated that the low-elevational species R. cautleoides was derived from the high-elevational species R. humeana. Divergence among species occurred during the middle to late Quaternary (0.01–1.48 Ma). The species distribution and phylogeographical pattern were inconsistent with a geographical barrier. Niche models and statistical analyses showed significant ecological differentiation. Main conclusions Divergence between R. humeana and R. cautleoides was recent and coincident with Quaternary climate cycles. Ecological niche differentiation within Quaternary refugia may have promoted speciation.

article The evolutionary diversifications of many taxonomic groups, especially those with limited dispersal ability, are often driven by key geological events, such as tectonic drift, continental collisions, and uplifts of mountains. Here, we use full range geographic sampling to create a dated molecular phylogeny for two genera of alpine gingers (Cautleya and Roscoea) in the Pan-Himalaya, and test the correlations between evolutionary diversifica- tion of this group and major geological events in the studied region. Our results revealed that the origination of their common ancestor and evolutionary split between the two genera occurred during the middle Eocene and the late Eocene to the early Oligocene, corresponding well to the proposed two early uplifts of the Himalayan- Tibetan Plateau.Roscoeaspecies,thehighest elevation gingers known, were then divided intodistinct Himalayan and Indochinese clades, simultaneous with the rapid extrusion of Indochina and accompanied by the third Himalayan uplift around the Oligocene/Miocene boundary. This study highlights the importance of evolutionary diversification of plants as an independent line of evidence to reflect tectonic events in the Himalayan- Indochinese region. © 2015 The Authors. Published by Elsevier B.V. on behalf of International Association for Gondwana Research. This is an open access article under the CC BY-NC-ND license

Water-mediated fertilization is ubiquitous in early land plants. This ancestral mode of fertilization has, however, generally been considered to have been lost during the evolutionary history of terrestrial flowering plants. We investigated reproductive mechanisms in the subtropical ginger Cautleya gracilis (Zingiberaceae), which has two pollen conditions - granular and filiform masses - depending on external conditions. We tested whether rain transformed granular pollen into filiform masses and whether this then promoted pollen-tube growth and fertilization of ovules. Using experimental manipulations in the field we investigated the contribution of water-mediated fertilization to seed production. Rain caused granular pollen to form filiform masses of germinating pollen tubes, which transported sperm to ovules, resulting in fertilization and seed set. Flowers exposed to rain produced significantly more seeds than those protected from the rain, which retained granular pollen. Insect pollination made only a limited contribution to seed set because rainy conditions limited pollinator service. Our results reveal a previously undescribed fertilization mechanism in flowering plants involving water-mediated fertilization stimulated by rain. Water-mediated fertilization is likely to be adaptive in the subtropical monsoon environments in which C. gracilis occurs by ensuring reproductive assurance when persistent rain prevents insect-mediated pollination.

Elucidating how variation in selection shapes the evolution of flowers is key to understanding adaptive differentiation processes. We estimated pollinator-mediated selection through female function in L-morph (long-style and short-anther phenotype) and S-morph (short-style and long-anther phenotype) flowers among four Primula secundiflora populations with different pollinator assemblages. Variation in pollinator assemblage strongly contributed to differences in reproductive success among populations and between morphs of the primrose species. A wider corolla tube width was selected in the bumblebee-dominated populations, whereas shorter corolla tube length and wider corolla tube width were selected in the syrphid fly-dominated populations. Morph-specific variation in pollinator-mediated selection on corolla tube length was detected in the syrphid fly-dominated populations. A shorter corolla tube was selected in the L-morph flowers. However, similar selective pressure on this trait was not observed in the S-morph flowers. These results show that variation in pollinator assemblage leads to variation in selection in space and between morphs. The findings highlight the potential forces of different pollinator agents in driving floral evolution in this primrose species., This paper researches the spatial and inter-morph variation in pollinator-mediated selection on floral traits in the heterostylous taxa, Primula secundiflora. Our results indicate that a wider corolla tube width was selected in the bumblebee-dominated populations, whereas shorter corolla tube length and wider corolla tube width were selected in the syrphid fly-dominated populations. Morph-specific variation in pollinator-mediated selection on corolla tube length was detected in the syrphid fly-dominated populations. The findings highlight the potential forces of different pollinator agents in driving floral evolution in this primrose species.

Distyly is a widespread floral polymorphism characterized by the flowers within a population showing reciprocal placement of the anthers and stigma. Darwin hypothesizes that distyly evolves to promote precise pollen transfer between morphs. Primula chungensis exhibits two types of anther heights, and these two types of anthers show pollen of two different size classes. To understand whether the stigma could capture more pollen grains from the anthers of the pollen donor as the separation between the stigma of pollen receiver and the anther of pollen donor decreased, the present research assessed the source of the pollen load in a series of open-pollinated flowers with continuous variation of style lengths. Individuals with continuous variation of style length were tagged, and the selected flowers in the tagged plants were emasculated the day before dehiscence. The stigma of the emasculated flowers was fixed in fuchsin gel at the end of blooming. We assessed the pollen sources on each stigma by taking photos under a microscope and measured the diameter of each conspecific pollen grain with ImageJ. We found that a shorter distance from the stigmas to the anthers of a pollen donor gave the flower a higher capacity to receive pollen from those anthers. Our result provides a new evidence that distyly could promote the pollen transfer between morphs, which is consistent with Darwin’s hypothesis of disassortative pollination. An alternative hypothesis for the evolution of distyly (e.g. selfing avoidance) might also be true, but less likely, because self-incompatibility would greatly avoid self-fertilization for many distylous species., Distyly, a well-known floral syndrome that was first identified by Charles Darwin, would be an ideal model to determine how a key floral syndrome is shaped by nature. Primula chungensis, a distylous species with simultaneous homo-, short- and long-styled morphs, exhibits some variations in the length of style. Using this species, we found that the stigma captured more compatible pollen as the separation between the stigma of the pollen receiver and the anther of the pollen donor decreased. Our results provide clear and novel evidence for the disassortative pollination hypothesis proposed by Charles Darwin, which will be helpful for our future understanding of the evolution of distyly.

Based on structural balance theory and signed network model, we investigate and analyze the signed social network of A company, and find the optimal balanced structure, and delineate the final signed digraph. In terms of the optimal balanced structure, managers can make employee of company achieve most concordant level and arrange employee with positive social relationships at one department as many as possible. Managers may also use the optimal balanced structure to coordinate the internal conflict, and to design the structure of employee of new program.

The targets and causes of phenotypic selection are crucial to understanding evolutionary ecology. However, few studies have examined selection quantitatively from multiple sources on the same trait identified the agent of natural selection experimentally. Here we quantified phenotypic selection on traits, including flowering phenology and aspects of floral display via female fitness, in the distylous perennial herb Primula alpicola. To determine the role of pollinators in generating selection effects on floral traits, we compared the phenotypic selection gradients in open-pollinated and hand-pollinated plants. Our results show that pollinator-mediated linear selection on flowering start and correlational selection on the number of flowers and scape height explains most of the net phenotypic selection on these traits suggesting pollinators played an important role in shaping floral diversity. We used path analysis and structural equation modeling (SEM) to examine how herbivores affected the relationship between floral traits and female fitness, but no significant selection was caused by seed predators. These results suggest pollinators, not herbivores maybe the significant agent of selection on flora traits.

Antisense oligonucleotides (ODNs) are therapeutic molecules that hybridize to complementary target mRNA sequences. To further overcome the poor cellular uptake of ODNs, we proposed a novel strategy to deliver ODNs by conjugating the anti-influenza A virus (IAV) ODN with a peptide showing high affinity to the hemagglutinin (HA) on the surface of IAV particles or the IAV-infected host cells. The HA-specific binding peptides were selected by phage display, and the individual binding clones are characterized by DNA sequencing, and the selected phage was further assayed by enzyme-linked immunosorbent assay. The final selected HA-binding peptide, SHGRITFAYFAN, was conjugated to an anti-IAV ODN. The delivery efficiency and the anti-IAV effects of the conjugated molecule were evaluated in a cell-culture and a mouse-infection model. The conjugated molecule was successfully delivered into IAV-infected host cells more efficiently than the anti-IAV ODN in vitro and in vivo. Furthermore, the conjugated molecule protected 80% of the mice from lethal challenge and inhibited the plaque count by 75% compared to the unconjugated molecule (60% and 40%). These findings demonstrate that the delivery of antisense oligodeoxynucleotides to infected tissues by a virus-binding peptide-mediated system is a potential therapeutic strategy against IAV.

The styles of the plants of genus Alpinia show a similar bending behavior. Each species has two types—hyper-type and cata-type. The styles of hyper-type bend downward first, and then bend upward second. The styles of cata-type also bend twice, but the bending direction is opposite to hyper-type. We tested the effects of light, IAA, and NPA on the style movement of Alpinia oxyphylla and Alpinia galanga, and analyzed the IAA distribution in their styles. We found that the effects of light were similar for the two species, but the two types of each species responded differently. The first style bending of hyper-type was downward when it was in dark, and was upward when in light; the second bending was upward if in light, and did not move if in dark. The two bendings of cata-type showed no obvious difference between in dark and in light. Effects of IAA and NPA were different for two species. For A. galanga, neither IAA nor NPA had obvious effects on the style bending. For A. oxyphylla, IAA enhanced the second bending of hyper-type and the two bendings of cata-type. NPA enhanced the second bending of hyper-type and the first bendings of cata-type, and significantly inhibited the second bending of cata-type. The results of IAA immunolocalization indicated that IAA was symmetrical in the styles of A. galanga both before the first bending and before the second bending in two types. However, in A. oxyphylla, IAA asymmetry was found in two types. Therefore, we hypothesize that the mechanisms of the style bending of Alpinia plants are different, not only between two types of each species, but also among species.

In this paper, we combine the complex network theory and the traditional software structure metrology to propose a new model for the study of the structural characteristics of the software---- Multi-dimensional measurement model of the software structure properties. The multi-dimensional measurement model of the software structure properties is divided into three parts. Each part has their own properties. In this model, the system is abstracted into a network model in the first step. Then we design the metric parameters considering both the complex network theory and the Object-Oriented software research and also give the definition and calculation method of these metric parameters. And on this basis we use the advantages of eclipse and complex network simulation tool pajek to calculate the metrics parameters designed before. Then give explanation to the experimental results which can demonstrate the reliability of the new model, which has also made a solid foundation for the following study of the software structure properties.

The degradation of various kinds of synthetic dyestuffs, such as dyestuff, textiles, leather, paper and plastics, stimulated a particular research interest in recent years. Nickel hydroxide and nickel oxide compounds stimulated a large interest in industrial and technical applications, for example as the active materials in electrochemical cycling and as a photocatalyst to remove organic dyes. In this paper, the mainly research is focused on the preparation process and removal properties of azo dye pollutants from aqueous solutions using Ni(OH)2 nanosheets or NiO nanosheets. The proposed research investigates the Ni(OH)2 nanosheets or NiO nanosheets that are important in understanding the structure, morphology and the photocatalytic performances. Ni(OH)2 nanosheets were synthesised by a simple chemical precipitation method using nickel chloride as precursors and ammonia as precipitating agent. The obtained Ni(OH)2 nanosheets can be successfully converted to NiO nanosheets via calcination under app...

The staminal lever mechanism of pollination in Salvia has been considered as a key innovation, which was proposed to contribute to adaptive radiation of the genus. Considering its sophisticated interaction with pollinators, we hypothesized that relevant floral traits in the lever mechanism might be subject to intense selection in natural populations. In the present study, Salvia digitaloides was employed to investigate phenotypic selection on the floral traits. The results indicated that there were large variations in the floral structural traits and spatial position of the stigma. No significant selection was detected on the plausible key trait, i.e. the stamen lever length. Strong stabilizing selection acted consistently on the size of corolla entrance; that is, the intermediate corolla entrance was at a selective advantage. Both corolla length and style exsertion were subject to opposite directional selection in both years; and corolla entrance height was subject to disruptive selection, which was attributed to divergent adaptation of the trait to different body-sized pollinators. Furthermore, correlational selection acted on a few pairs of traits which described corolla entrance size and stigma position. Flower production was consistently subject to significantly positive directional selection in both years. In conclusion, it was most likely that floral traits involved in the staminal lever mechanism evolved in a functionally integrated manner for the enhancement of pollination efficiency in the natural population of S. digitaloides.