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Moxifloxacin (MFX) shows good in vitro activity against Mycobacterium abscessus and can be a possible antibiotic therapy to treat M. abscessus infection; however, other studies have shown a lower or no activity. We aimed to evaluate MFX activity against M. abscessus using zebrafish (ZF) model in vivo. A formulation of M. abscessus labeled with CM-Dil was micro-injected into ZF. Survival curves were determined by recording dead ZF every day. ZF were lysed, and colony-forming units (CFUs) were enumerated. Bacteria dissemination and fluorescence intensity in ZF were analyzed. Inhibition rates of MFX and azithromycin (AZM, positive control) were determined and compared. Significantly increased survival rate was observed with different AZM concentrations. However, increasing MFX concentration did not result in a significant decrease in ZF survival curve. No significant differences in bacterial burdens by CFU loads were observed between AZM and MFX groups at various concentrations. Bacterial fluorescence intensity in ZF was significantly correlated with AZM concentration. However, with increasing MFX concentration, fluorescence intensity decreased slightly when observed under fluorescence microscope. Transferring rates at various concentrations were comparable between the MFX and AZM groups, with no significant difference. MFX showed limited efficacy against M. abscessus in vivo using ZF model. Its activity in vivo needs to be confirmed. [ABSTRACT FROM AUTHOR]

Climate change has had a significant impact on natural ecosystems and endemic species around the world and substantial impacts are expected in the future. As a result, knowing how climate change affects endemic species can help in putting forward the necessary conservation efforts. The use of niche modeling to predict changes in species distributions under different climate change scenarios is becoming a hot topic in biological conservation. This study aimed to use the global circulation model (CMIP5) to model the current distribution of suitable habitat for three critically endangered Aloe species endemic to Kenya and Tanzania in order to determine the impact of climate change on their suitable habitat in the years 2050 and 2070. We used two representative concentration pathways scenarios (RCP4.5 and RCP8.5) to project the contraction of suitable habitats for Aloe ballyi Reynolds, A. classenii Reynolds, and A. penduliflora Baker. Precipitation, temperature and environmental variables (Potential evapotranspiration, land cover, soil sedimentary and solar radiation) have had a significant impact on the current distribution of all the three species. Although suitable habitat expansion and contraction are predicted for all the species, loss of original suitable habitat is expected to be extensive. Climate change is expected to devastate >44% and 34% of the original habitats of A. ballyi and A. classenii respectively. Based on our findings, we propose that areas predicted to contract due to climate change should be designated as key protection zones for Aloe species conservation. [Display omitted] • The ecological niche of Aloe ballyi , A. penduliflora and A. classenii is mainly affected by environmental variables. • Aloe species will be generally negatively impacted by the climate change in the East Africa. • Climate change is predicted to shift the existing suitable habitat range of Aloe species. • Endemic Aloe species critically endangered need urgent attention for conservation. [ABSTRACT FROM AUTHOR]

Novel Bi and/or Si substituted LiEu(MoO 4 ) 2 phosphors, where Bi was used as sensitizer to enhance the emission intensity and Si was used as substitution to improve the excitation efficiency, were prepared using the sol–gel method, and the photoluminescent properties of the resulting phosphors were intensively investigated. All samples can be excited efficiently by UV (395 nm) light and emit bright red light at 614 nm, which are coupled well with the characteristic emission from a UV-LED. In the Bi 3+ -doped samples, the intensities of the main emission line ( 5 D 0 – 7 F 2 transition at 614 nm) are strengthened because of the energy transition from Bi 3+ to Eu 3+ . With the substitution of Mo 4+ by Si 4+ , there are no significant changes in the emission peak positions, but the emission intensity was significantly enhanced under 395 nm excitation. Particularly, the LiEu 0.9 Bi 0.1 (Mo 0.97 Si 0.03 O 4 ) 2 phosphor doped with both Bi and Si demonstrates superior comprehensive photoluminescence properties with an excellent combination of easy excitation in the near UV range, bright emission intensity, high PL quantum efficiency as well as suitable decay time, which are very suitable for application as red phosphor for near UV type LEDs. [ABSTRACT FROM AUTHOR]

One of the anthropogenic causes affecting species distribution is climate change, which has significant implications for species conservation. However, little is known about the effects of changes in parasitic plant distribution on community-level interactions. Parasitic flowering plants make a limited numerical contribution to biodiversity. Their lifestyle may exhibit a moderate to the high degree of host dependence. Because of this host dependence, parasites may be more affected by environmental changes, such as climate change, compared to autotrophic representatives. To our knowledge, the effects of different climate change scenarios and their environmental variables on parasitic plants and their hosts have not yet been studied. This study aimed to construct a model which shows the current and future potential effects of climate change on the distribution of the two holoparasitic plants Hydnora abyssinica A.Br., and H. africana Thunb. in comparison to their respective Fabaceae and Euphorbiaceae hosts. We projected the future distribution of these species and their host plants using five models, nine bioclimatic, and five environmental variables. The global circulation model (CMIP5) for the years 2050 and 2070, applying two representative concentration pathways scenarios (RCP4.5 and RCP8.5) projected a 41–64% contraction of suitable habitats for H. abyssinica. For H. africana , more stable conditions are estimated, with a 12–28% contraction in suitable habitats, making this species putatively less prone to climate change effects, although this species has a more restricted distribution compared to H. abyssinica. Because climate change could affect the host differently than the parasites, the impact on the parasite could potentially be exacerbated due to host plant dependence. The models predict that the host plant distribution will be less affected, except for Vachelia Karroo, Vachellia xanthophloea, and Euphorbia gregaria, which indicated high contraction (40–66%). The predicted host species distribution ranges will only partially overlap with the respective distribution of the parasite. [Display omitted] • Climate change impacts on holoparasitic species and their hosts are poorly documented. • We employed a combination of approaches and environmental predictors to bridge the gap. • Temperature and precipitation significantly influenced Hydnora and host distribution. • Climate risk in tropical holoparasitic species may be higher than projected. • In diverse tropical settings, proactive conservation activities are required. [ABSTRACT FROM AUTHOR]

Abstract: Six new tin complexes of the formulae [(Ph3Sn)2(PhSn)10(Sn)2(μ2-O)8(μ3-O)18(C7HCl3O3)2] (1), {[(n-Bu)3Sn]2(C7HCl3O3)} n (2), [(Me3Sn)2(C7HCl3O3)] n (3), [(Ph2Sn)(C7HCl3O3)2] (4), [(n-Bu)2Sn(C7HCl3O3)2] (5) and [(Me2Sn)4(C7HCl3O3)2(μ3-O)2(CH3O)2] (6) have been obtained from 3,5,6-trichlorosalicylic acid and an organotin chloride or organotin oxide. All the complexes were characterized by elemental analysis, FT-IR and NMR (1H, 13C and 119Sn) spectroscopy; complexes 1, 3 and 6 were further characterized X-ray crystallography diffraction analyses. The structural analyses reveal that complex 1 has a novel cage structure, which contains two triphenyltin nuclei, 10 monophenyltin nuclei and two inorganic tin nuclei; complex 3 has an infinite chain structure and complex 6 displays a typical ladder structure. [Copyright &y& Elsevier]

Abstract: We studied reversible anther opening in a dichogamous aquatic plant Butomus umbellatus L. (Butomaceae) to assess its consequence on male fitness. Light microscope observations indicated that stomium breakage was simultaneous in all the anthers within an opening flower; however, detachment of the epidermis and outward bending of the anther wall were asynchronous. SEM observations showed that epidermis cells alternated between orbicular and crinkly shapes in response to absorption and loss of water. This generated centripetal and centrifugal forces which were significant enough to cause inward and outward bending of the anther wall, thus causing opened anthers to close and closed anthers to re-open respectively, depending on relative humidity of the environment. Behaviour of in vitro and in situ anthers from different whorls within a flower was recorded under four regimes of relative humidity or under a water-spraying treatment. The three stages of anther opening namely stomium breakage, epidermis detachment and outward bending of the anther wall were affected differently by moisture levels. Outward bending of anther wall which was responsible for reversible anther opening was mainly dependent on environmental relative humidity levels. Notably, on sunny days, anther re-opening was inhibited at high relative humidity for in vitro anthers, but not for anthers in situ. Reabsorption, rather than evaporation was responsible for reversible anther opening for this aquatic plant. Water-spraying treatment indicated that flowers with re-closed anthers attracted fewer pollinators. Results using pollen stainability and germinability of pollen on stigmas for pollen grains from different treatments also showed the mechanism of reversible anther opening significantly prolonged pollen longevity by maintaining high viability in a simulated rainy. Discontinuous pollen presentation due to reversible anther opening avoided unfavorable pollination environment and pollen loss. [Copyright &y& Elsevier]

Abstract: Five new diorganotin(IV) complexes of the types {(Me2Sn)2[μ4-(C8H3NO6)](μ3-O)} n (1), {(Me2Sn)2[μ3-(C8H8O4)](μ3-O)} n (2), {(Me2Sn)2[μ4-(C8H10O4)](μ3-O)} n (3) {(Me2Sn)2[μ4-(C8H10O4)](μ3-O)} n (4) and {(Me2Sn)2[μ4-(C10H14O4)](μ3-O)} n (5) have been synthesized by reactions of 5-nitroisophthalic acid, meso-cis-4-cyclohexene-1,2-dicarboxylic, meso-cis-1,4-cyclohexanedicarboxylic acid, meso-cis-1,3-cyclohexanedicarboxylic acid and chiral cis-(1R,3S)-(+)-camphoric acid with trimethyltin chloride under hydrothermal condition. All complexes were characterized by elemental analysis, IR, 1H NMR, 13C NMR, 119Sn NMR and X-ray crystallography. The structural analyses show that complex 1 has a 1D infinite polymeric chain in which 5-nitroisophthalic acid acts as a tetradentate ligand coordinating to dimethyltin(IV) ions, complexes 2, 3 and 4 possess 2D polymeric structures in which dicarboxylate acid act as tridentate or tetradentate ligands coordinating to dimethyltin(IV) ions, complex 5 possesses a irregular 3D framework in which chiral cis-(1R,3S)-(+)-camphoric acid acts as a tetradentate ligand coordinating to dimethyltin(IV) ions. [Copyright &y& Elsevier]

Abstract: Manually controlled dredging process is of low production and poor efficiency. To raise production and to reduce unit cost, automatic control of dredging process is a desired solution to the problem. The automation of dredging operations has been actively researched by scholars all over the world for a couple of years. Based on the prior research results of dredging operations, an expert control system that is aimed to realize online operation optimization and automatic control of dredging process is introduced in this paper. Details on the problem to be dealt with and the expert system (ES) based solution are introduced; the focus of this paper is put on the architecture, knowledge presentation and inferential mechanism of the ES. An expert control software program is developed with C++. Based on the test platform constructed the performance of the ES is evaluated by comparison. Experiments show that the expert control scheme presented is capable of realizing automatic dredging process control with acceptable performance. [Copyright &y& Elsevier]

Abstract: Faults during dredging process often caused serious damages on dredging system. High maintenance costs and prolonged fault recovering process often make dredging production and profit low. An online fault diagnosis and prevention expert system that is aimed to prevent fault occurrence and to quicken the recovering process is introduced in this paper. For the complexity of fault judging and prevention process and frequently varying dynamics of dredging operations, hybrid structure and inference process are adopted in the expert system. ANNs are introduced to adapt the varying system dynamics and to predict system state. Designed expert application is also featured by online fault prevention and recovering decisions. Preliminary test has been carried out in actual engineering project and results of performance evaluation experiment are also introduced. [Copyright &y& Elsevier]

Dam observations indicated that low-air concentration can avoid cavitation erosion. In the present study, a device with micron-scale orifice diameters was designed to introduce air bubbles in water, to study the effects of the reduction of cavitation erosion in an ultrasonic environment. The experimental results showed that low-air concentration imposes prominent effects on the development of cavitation erosion and can significantly reduce the effect of cavitation on the structural damage. If the air concentration and bubble quantity reach certain values, the erosion reduction effects do not change as the air conditions are altered. Based on the analysis of the average erosion reduction efficiency of a single-air bubble, aeration and erosion protection for the wall surface can be achieved. Moreover, a discharge tunnel with high-head and high-speed water flow is analyzed. With a high velocity and low-air concentration flow in the open channel, no cavitation erosion on the tunnel structure was observed. Combined with the present experimental results, this shows that the effect of the aeration erosion reduction can be evaluated and analyzed if the air bubble quantity meets the erosion reduction requirement. Consequently, the effect of aeration can be recognized effectively by number of air bubbles, and can promote the design and analysis of the aeration erosion reduction in hydraulic engineering. • Investigated the effects of air concentration and air bubble quantity on cavitation erosion. • Investigated the relationship between air pressure and air bubble size. • Combined with prototype observation of Xiaolangdi Project to illustrate a high velocity and low-air concentration flow in the open channel, no cavitation erosion on the tunnel structure was observed. [ABSTRACT FROM AUTHOR]

The molecular mechanisms responsible for plant adaptations to aquatic habitats remain poorly known. In this study, we aimed to detect selection on orthologous genes among the submerged aquatic plant Ranunculus bungei , semi-aquatic R. sceleratus , and terrestrial R. brotherusii and R. cantoniensis , in order to identify candidate genes involved in the adaptive transition from terrestrial habitats to aquatic habitats and if they differ between R. bungei and R. sceleratus . We used 884 previously reported 1:1:1:1 orthologous genes among the four species (one ortholog is represented in each species). We identified 177 genes of R. bungei and R. sceleratus that are potentially under positive selection. Among them, a set of candidate genes for adaptation to an aquatic habitat were recognized. These include several genes that are associated with photosynthesis, vacuoles, ethylene and oxygen receptors, and aerenchyma formation. Gene Ontology analyses suggest that the submerged R. bungei has a higher percentage of positively selected genes associated with the chloroplast and other plastids, while the semi-aquatic R. sceleratus has a higher percentage associated with metabolic processes. This study represents a step forward towards understanding the molecular mechanism of plant adaptations to aquatic habitats. [ABSTRACT FROM AUTHOR]

• Global climate change causes an increasing threat to coastal species,with the potential extinction of a lot of legume species. • We modelled the distribution of eleven legume taxa at local scales using environmental variables. • The selected legume taxa ecological niches are influenced mainly by mean diurnal range temperature, precipitation of the coldest quarter, and elevation. • Irrespective of the climate change scenario, B. mombassae, C. lukei , and S. speciosa were observed to be most vulnerable to climate change. Predicting the responses of threatened tropical plant species to global climate change has been considered to be critical for assessing changes in species distribution and evaluating their conservation status. In reflecting on the vast species richness, East Africa has long been recognised as a hotspot of biodiversity, but very little is known about the vulnerability of the endemic plant diversity to anthropogenic introduced climate changes. This study evaluated the potential impacts of global climate change on plant species ranges in coastal East Africa by predicting the extent and direction of projected changes in climatic suitability. Specifically, we employed species distribution modelling in MaxEnt to identify species experiencing the highest threat of range declines. To do so, we evaluated climatic suitability for eleven legume species using one global climate model and two greenhouse gas emissions scenarios for present and future climates. The findings indicated that the mean AUC and TSS values of the focal taxa ranged from 0.818 to 0.992 and from 0.780 to 0.851, respectively, indicating that the MaxEnt model's prediction accuracy was good or exceptional. Occupancy and abundance of nine species were positively associated with low elevations, high relative humidity, and warmer temperatures in the coastal regions. Regardless of species, precipitation of the warmest quarter and mean temperature of the wettest quarter exhibited a minor impact on the distribution. Furthermore, the probable distribution regions of these species ranged from 77,270 km2 to 282,297 km2. To our knowledge, this study is the first to appraise the distribution of threatened species within Fabaceae in coastal East Africa. The current findings provide a critical assessment framework for the conservation and management of Fabaceae in the region. [ABSTRACT FROM AUTHOR]

The submersed species Egeria densa possesses an inducible C 4 -like photosynthetic system after exposure to low CO 2 concentrations. Four full-length and one partial cDNAs encoding plant-type PEPC were identified, named EdPEPC 1-5; and one partial cDNA encoding bacterial-type PEPC was identified. None of the C 4 -signature amino acid substitutions which were found in C 4 -type PEPC isoforms of terrestrial C 4 plants were found in EdPEPC s. Real-time qPCR experiments indicated that in the high CO 2 concentration, all these isoforms were expressed at low levels in leaves and stems. However after exposure to low CO 2 concentration, EdPEPC 1 was significantly up-expressed in the stems and leaves, and may thus correspond to the C 4 -form. The results of enzyme assays and western blotting showed increases in the activities and amount of PEPC in the leaves and stems after incubation at low [CO 2 ]. EdPEPC 1, gene that responds to low [CO 2 ], might be involved in the emergence of the inducible C 4 -like mechanism in E. densa . For the first time in submersed plants, the results suggested that stems as well as leaves were likely to be involved in the C 4 -like mechanism. [ABSTRACT FROM AUTHOR]

This study attempts to identify the rock cutting efficiency by several descriptor methods of chip size distribution such as coarseness index, Rossin-Rammler function, and fractal function by sieve analysis. In this context, the characteristic of rock chips produced during relieved and unrelieved cutting tests was examined. The cutting tests were performed by using a conical pick on five sandstones with uniaxial compressive strength varying from 17.91 to 85.98 MPa. Different levels of cutting depth and line spacing were applied in the course of the tests. The specific energy was also calculated. Based on sieve analysis of the chips collected after the cutting tests, the relationships between the distribution parameters of rock chips and cutting parameters including depth of cut, line spacing, and specific energy were investigated. In this context, we aimed to determine the capability of each chip size distribution method and to associate with the rock cutting efficiency, in which some of the major parameters in consideration of the rock cutting process are included. Based on the statistical analyses, several regression equations were proposed according to relieved and unrelieved cutting modes. In conclusion, we found that there are significant relationships between depth of cut and coarseness index, size parameter and distribution parameter. The coarseness index is found to be very reliable to evaluate the cutting efficiency and Rosin-Rammler function is an alternative practical method to be utilized. The rock chips conform to the fractal distribution law. However, the relationship between the fractal dimension and specific energy is weaker compared to the relationship between specific energy and coarseness index in this study. [ABSTRACT FROM AUTHOR]

Abstract: Genetic variation and clonal diversity of 14 populations of the endangered clonal herb Sagittaria natans and its widespread congener S. trifolia were investigated using inter-simple sequence repeat (ISSR) markers. Using nine effective ISSR primers, a total of 92 DNA fragments were generated with 54 (percentage of polymorphic loci, PPL: 58.7%) being polymorphic. A higher level of genetic diversity among populations was found in S. natans (PPL: 48.9%) than S. trifolia (PPL: 32.6%). Analysis of molecular variance (AMOVA) showed that in each species a similar proportion of the total genetic variation resided within and among populations, and that between species there was a moderate genetic differentiation (Gst: 0.601). With the use of 54 polymorphic ISSR markers, we identified 116 genets among 138 samples from five S. natans populations, and 93 genets among 215 samples from nine S. trifolia populations. The proportion of distinguishable genets (PD: mean 0.82) and Simpson''s diversity index (D: mean 0.95) for S. natans exhibited higher degree of clonal diversity compared to S. trifolia (PD: mean 0.42; D: mean 0.89). Sexual reproduction might have been played an important role in maintaining and increasing the clonal diversity in both species. Recent and on-going decimation of S. natans populations in the region appear not to have had a major impact on genetic diversity in this rare plant. [Copyright &y& Elsevier]

• We firstly report the complete chloroplast genome of Menyanthaceae. • The rpl 2 gene was missing in all Nymphoides. • The divergence hotspots (gene ccsA and intergeneric region trnK-UUU-rps16) were determined. • The monophyletic position of Nymphoides as well as Menyanthes was confirmed. The Menyanthaceae is a family of aquatic flowering plants with diverse leaf and floral traits, leading to uncertainty about taxonomic, phylogenetic and evolutionary relationships within this family. In order to study the molecular evolution and phylogeny within Menyanthaceae, we sequenced the complete chloroplast (cp) genomes of six representative species from Nymphoides and the monotypic genus Menyanthes. In our study, the chloroplast genomes sizes ranged from 151,985 bp for Nymphoides coronata to 154,313 bp for Menyanthes trifoliata in length. Large Single-Copy (LSC), Small Single-Copy (SSC) and Inverted Repeat regions (IRs) portrayed normal length similar to most reported angiosperms. Menyanthaceae family chloroplast genomes possess a typical quadripartite structure, conserved in genomic structure and gene order. The size of the cp genome for the seven Menyanthaceae species consistently encoded 112–113 unique genes, including 79–80 protein-coding genes, 29 transfer RNA (tRNAs), and four ribosomal RNAs (rRNAs), 17 genes were duplicated in the inverted repeat region (IR) in both Nymphoides to 18 genes in Menyanthes respectively. Comparative analysis of the chloroplast genomes showed that Nymphoides species have lost the rpl2 intron which could be a derived feature in Nymphoides species. Phylogenetic analyses were conducted using 70 protein-coding genes in other families in order Asterales. Menyanthaceae divided into two clades with robust support. The genus Nymphoides was closely related to Menyanthes. In all studied chloroplast genomes, 30 codons had relative synonymous codon usage RSCU > 1 (higher preference), 29 codons had RSCU < 1 (low preference). The largest nucleotide diversity was found in gene ccsA in CDS region and trnK-UUU-rps16 in the IGS region. Most simple sequence repeats like in other reported angiosperms were mononucleotides ending with A/T in all cp genomes. [ABSTRACT FROM AUTHOR]

Highlights • Almost the entire geographical distribution of O. acuminata var. jingxiensis in China was sampled. • Phylogenetic analyses revealed a remarkable genetic structure among populations. • The two major genetic clusters were consistent with geographical regions. Abstract O. acuminata var. jingxiensis , an endangered endemic species, is only distributed in rivers or streams in karst areas of southwest China. In this study, the genetic variation of 10 natural populations sampled from karst rivers was detected using 12 SSR markers. The results revealed a moderate level of genetic diversity within the populations (mean H E = 0.441, I = 0.781) and population structure which significantly correlated with geographic distance (r = 0.825, P < 0.01). This pattern could be attributed to either restricted gene flow (Nm = 0.341) between the long-isolated populations or the occurrence of biparental inbreeding in closely distributed individuals (F IS = 0.362). The analysis of molecular variance (AMOVA) revealed a high level of genetic variation among the populations (F ST = 0.423) of O. acuminata var. jingxiensis and accounted for over 55% of the total genetic differentiation. Compared to gene flow, genetic drift is more likely to promote the current genetic structure because of low gene exchange among isolated habitats. Complete geographical isolation offers an opportunity for allopatric speciation at relatively small spatial scales that promotes high endemism. Our result indicated that it is likely that cryptic varieties exist in O. acuminata , such as Baishou (BS) and Luzhai (LZ) populations. Based on the available results, both in situ and ex situ efforts should be used to conserve this species. [ABSTRACT FROM AUTHOR]

Ottelia acuminata (Gagnep.) Dandy is an aquatic plant species that is endemic to the Yunnan-Guizhou Plateau (YGP) and adjacent areas of southwestern China. The taxonomic status of this species is still controversial and the main debate is on the distinction of the varieties. To determine the extent of genetic divergence among the varieties of this species, we studied the phylogenetic relationship and divergence time among representative plants of previously recorded varieties. Our sampling included 169 individuals representing five recorded varieties from 11 populations. We sequenced five chloroplast DNA (cpDNA) non-coding regions and nuclear ITS region. We identified a total of 20 different cpDNA haplotypes and seven ITS ribotypes. Phylogenetic analyses revealed that cpDNA haplotypes from each variety except for O. acuminata var. jingxiensis formed a distinct lineage but only two ITS ribotype lineages were grouped by variety. Our results suggested that most of the varieties described based on morphological characters represent genetically differentiated entities. The divergence times between varieties were estimated to be at the late Tertiary and early Quaternary. Moreover, the genetic differentiations among O. acuminata populations (or varieties) might result from the limited gene flow among isolated populations in different aquatic environments, which were probably formed during the Pliocene and Pleistocene geologic movements of the YGP. [ABSTRACT FROM AUTHOR]

Abstract: The effects of floral herbivores on floral traits may result in alterations in pollinator foraging behaviour and subsequently influence plant reproductive success. Fed-upon plants may have evolved mechanisms to compensate for herbivore-related decreased fecundity. We conducted a series of field experiments to determine the relative contribution of floral herbivores and pollinators to female reproductive success in an alpine herb, Pedicularis gruina, in two natural populations over two consecutive years. Experimental manipulations included bagging, hand supplemental, geitonogamous pollination, and simulated floral herbivory. Bumblebees not only avoided damaged flowers and plants but also decreased successive visits of flowers in damaged plants, and the latter may reduce the level of geitonogamy. Although seed set per fruit within damaged plants was higher than that in intact plants, total seed number in damaged plants was less than that in intact plants, since floral herbivory-mediated pollinator limitation led to a sharp reduction of fruit set. Overall, the results suggest that resource reallocation within inflorescences of damaged plants may partially compensate for a reduction in seed production. Additionally, a novel finding was the decrease in successive within-plant bumblebee visits following floral herbivory. This may increase seed quantity and quality of P. gruina since self-compatible species exhibit inbreeding depression. The patterns of compensation of herbivory and its consequences reported in this study give an insight into the combined effects of interactions between floral herbivory and pollination on plant reproductive fitness. [Copyright &y& Elsevier]

Abstract: Floral colour polymorphism occurs in many species throughout the angiosperms but the mechanisms of selection remain unclear. In this study, we studied the pollen–pistil interactions between different Butomus umbellatus plants, a clonal aquatic plant with red and white-flowered individuals. Results indicated that red-flowered plants have lower asexual and sexual reproductive output compared to white-flowered plants in monomorphic populations, even though there are no differences in flower characteristics and pollination systems. On the other hand, in polymorphic populations, sexual reproductive output in red-flowered plants increases while asexual reproductive output decreases considerably. However, this remains unaffected in white-flowered plants. Artificial pollination treatments revealed asymmetric pollen–pistil interactions between red and white-flowered individuals. Inter-morph crosses increase seed production only when the red-flowered plant is maternal. Moreover, pollen grains of white-flowered plants significantly enhance not only female fitness by way of greater seed yields, but also male fitness by promoting fertility of pollen on stigma within a flower. Such special pollen–pistil interactions might form one kind of balancing selection and actively maintain both genotypes of the two morphs. These findings may enrich our understanding of mechanisms of maintaining plant reproductive polymorphism. [Copyright &y& Elsevier]

Abstract: Inter-simple sequence repeat (ISSR) markers were used to investigate the genetic variation of 14 populations of Batrachium bungei (Ranunculaceae) from the Hengduan Mountains of China, which is a global biodiversity region that is poorly studied. A total of 75 bands with 52 polymorphic loci were generated from the ten primers used in this study. A total of 155 different genotypes or clones were identified among the 442 samples. A low level of genetic diversity within population and high genetic differentiation among populations were revealed in this study. Factors, such as inbreeding, clonal growth, bottlenecks, population isolation and founder events during postglacial recolonizations, might have played important roles in shaping the population structure of B. bungei. [Copyright &y& Elsevier]

Abstract: We examined chloroplast DNA (cpDNA) atpB–rbcL intergenic spacer sequences variation within Sagittaria potamogetifolia, an endangered and endemic marsh herb in China. Sequence data were obtained from 54 individuals in six extant populations of the species. Sequences appeared to evolve neutral (Tajima''s criterion D =−1.59826, 0.1> P >0.05 and Fu and Li''s tests D*=−1.44484, P >0.1; F*=−1.83446, P >0.1). Eleven haplotypes were identified in S. potamogetifolia. A relatively high level of haplotype diversity (h =0.0.699) and low level of nucleotide diversity (pi=0.0035±0.0020) were detected in S. potamogetifolia. Pairwise comparisons of F st and Nm deduced from cpDNA variation suggested no significant genetic differentiation between populations of S. potamogetifolia excepted for the WY-1 population. Low genetic differentiation among populations and also among regions was consistently indicated by both hierarchical analyses of molecular variance (AMOVA) and the structure of a neighbor-joining tree. Lack of population differentiation between populations or between regions in cpDNA sequences may be due to effects of lower substitution rates or lineage sorting. In the minimum spanning network, all tip haplotypes except for the haplotype J were unique to a particular population, while the interior nodes except for the haplotype E were widespread (haplotype A). From nested clade analysis (NCA), the evolutionary events such as restricted gene flow with isolation by distance and allopatric fragmentation were inferred to responsible for the current distribution of S. potamogetifolia populations, as well as their genetic diversity. [Copyright &y& Elsevier]

Abstract: Secondary brain injury plays a pivotal role in the outcome of patients suffering from traumatic brain injury (TBI). The mechanisms underlying secondary brain injury are complex and interrelated. Previous studies focused on one of these mechanisms have been proved to be ineffective in clinical practice. Therefore, a target, which can interrupt multi-mechanisms underlying TBI, is desirable. Nrf2–ARE pathway has been proved to be the key regulator in reducing oxidative stress, inflammatory damage and accumulation of toxic metabolites, which are all involved in TBI. However, whether Nrf2–ARE pathway is activated after TBI has not been studied. In the present study, the nuclear Nrf2 protein level was detected by Western blot, and the mRNA levels of heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase-1 (NQO1), two Nrf2-regulated gene products, were determined using reverse-transcriptase polymerase chain reaction (RT-PCR) 24h after TBI. Furthermore, we also localized the expression of Nrf2 and HO-1 using immunohistochemical study. After TBI, the nuclear Nrf2 protein level was significantly increased, and the mRNA levels of both HO-1 and NQO1 were also up regulated. Moreover, both Nrf2 and HO-1 were localized in the same types of cells. According to these results, it could be postulated that Nrf2–ARE pathway was activated in brain after TBI. [Copyright &y& Elsevier]

Abstract: The levels and pattern of the genetic variation within and among populations of the endangered fern Ceratopteris pteridoides (Hook.) Hieron in China were investigated using inter-simple sequence repeat (ISSR) markers. Thirteen ISSR primers used in the study amplified 125 reproducible bands with 56 (PPB=44.8%) being polymorphic, indicating a relative low level of genetic diversity at the species level. Genetic diversity varied greatly among populations with the PPB values ranging from 14.4% to 32%. The coefficient of genetic differentiation between populations (Gst) was 0.297, indicating low level of genetic variation between C. pteridoides populations. AMOVA analysis also revealed a low level of genetic differentiation among the five populations. Of the total genetic diversity, 26.17% was attributable to among-population diversity. The UPGMA cluster of all samples showed that individuals from the same population occasionally failed to cluster in one distinct group indicating extensive inter-population gene flow among the remaining populations of C. pteridoides in China. A Mantel test showed no significant correlation between genetic distance and geographic distance (r =0.44, P =0.91) suggesting that gene flow was not restricted geographically. A number of ways including clonal growth, genetic drift and inbreeding, the extensive hydrologic connectivity among populations, which facilitated long-distance gene flow, might have affected the genetic profiles of C. pteridoides. [Copyright &y& Elsevier]

Abstract: Genetic variation and clonal diversity of three natural populations of the rare, highly clonal marsh herb Caldesia grandis Samuelsson were investigated using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. Both of the markers worked effectively in clone identification of C. grandis. RAPD markers detected more diversity than ISSR markers in the three populations examined. Of the 60 RAPD primers screened, seven produced highly reproducible bands. Using these primers, a total of 61 DNA fragments were generated with 52 (85.25%) being polymorphic indicating considerable genetic variation at the species level. Analysis of molecular variance (AMOVA) showed that a large proportion of genetic variation (81.5%) resided within populations, while only a small proportion (18.5%) resided among populations. With the use of 52 polymorphic RAPD markers, we were able to identify 127 genets among 342 samples from three populations. The proportion of distinguishable genets (PD: mean 0.37), Simpson''s diversity index (D: mean 0.91), and evenness (E: mean 0.78) exhibited high levels of clonal diversity compared to other clonal plants. These results imply that sexual reproduction has played an important role at some time during the history of these populations. Nevertheless, the high level of diversity could have been also partially generated from somatic mutations, although this is unlikely to account for the high diversity generally found among C. grandis genets. [Copyright &y& Elsevier]

Abstract: The genetic diversity of 56 individuals of Isoëtes hypsophila Hand.-Mazz. from China was investigated by ISSR. Twelve primers were screened from 65 primers, and a total of 119 DNA fragments were scored, of these, 82% were polymorphic bands, which indicated that high levels of genetic variation existed in the natural populations. Genetic diversity varied greatly among populations with the percentage of polymorphic band (PPB) values ranging from 8 to 35%. An analysis of molecular variance (AMOVA) was used to apportion the variation between regions, among populations within regions, and within populations. Results indicated that most of the variance (85%) occurred between Yunnan and Sichuan. The variances among populations within regions and within populations, however, were only 5 and 10%, respectively. In the among-population analysis, the larger part of genetic variation (77%) resided among populations, and less (23%) presented differences within populations. UPGMA cluster analysis showed that there was no distinct genetic differentiation between populations from Sichuan province. A number of causes including limited gene flow, genetic drift and inbreeding might have led to these observed genetic profiles of I. hypsophila. [Copyright &y& Elsevier]

Carbon dioxide (CO 2) is one of the vital resources for plants and its concentrations in the atmosphere have been on the increase globally from the 18th century, and continue to rise at approximately 0.4% per year. Atmospheric CO 2 enrichment could possibly modify growth and chemical profiles of plants, as well as plant–insect interactions. The present study investigated the effects of elevated atmospheric CO 2 on stem diameters, above-ground biomass and secondary metabolite components of both terrestrial and aquatic forms of Alternanthera philoxeroides. Stem fragments of the weed were grown in six Open Top Chambers (OTCs): three chambers of ambient (~400 ppm) and three chambers of elevated (~1000 ppm) CO 2 levels to simulate the current and future CO 2 levels, respectively, based on prediction by IPCC (2013). Total dry weights of leaves and stems, as well as stem diameters were measured to evaluate growth and biomass accumulation in A. philoxeroides. Furthermore, chemical analyses were performed on leaf tissues of plants grown under both elevated and ambient atmospheric CO 2 treatments to determine the concentration of secondary metabolites (phenolic acids and flavonoids). Results of the analyses revealed that CO 2 enrichment significantly increased stem diameters and enhanced above-ground biomass accumulation in both aquatic and terrestrial environments. Enriched CO 2 atmosphere treatments increased concentration of secondary metabolites in leaf tissues, with leaves of plants grown under elevated CO 2 exhibiting remarkably higher concentrations of phenolic acids and flavonoids. Total flavonoid content increased by 51.02% in aquatic plants and by 99.03% in terrestrial plants. Total phenolic content increased by 29.57% in aquatic plant leaves while in terrestrial plant leaves the increase was by 61.11%. Above-ground biomass accumulation and increase in stem diameters could enhance competitive ability of the species and its ability to invade and colonize new habitats in response to a future CO 2 -enriched atmosphere. • Effect of enriched CO 2 atmosphere on stem diameters, above-ground biomass, and secondary metabolites of terrestrial and aquatic forms of Alternanthera philoxeroides were studied. • CO 2 enrichment significantly increased stem diameters and enhanced above-ground biomass accumulation in both aquatic and terrestrial plants. • Concentration of phenolic compounds in leaf tissues in elevated CO 2 treatments increased considerably. • Above-ground biomass accumulation and increase in stem diameters could enhance competitive ability A.philoxeroides to invade and colonize new habitats in response to future CO 2 -enriched atmosphere. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four water lily species were modeled in Maximum entropy. • Past and future projection scenarios were Last Glacial Maxima (LGM), Mid Holocene (MH) and Pathways (RCPs). • Low (2.6), Medium (4.5) and High (8.5) carbon emissions Representative Concentration. • The model indicated good and reliable performance with mean AUC > 0.8. • Greater change is projected in the past compared to future projections. Mapping and modeling suitable habitat and distribution of aquatic species is important to help assess the impact of factors such as climate change in affecting the shift, decline, or expansion of species habitat ranges. In Africa, the distribution of water lily (Nymphaea) species is geographically varied and the habitats suitable for individual species are prone to effects of global warming, though only limited conservation measures have been taken to date in aquatic environments. In this study, four widely distributed water lily species (N. nouchali , N. micrantha , N. lotus , and N. heudelotii) were modeled using MaxEnt which highlighted the individual species' suitable climatic distribution. The current distribution indicates a partial distribution of N. nouchali in West Africa unlike N. micrantha, N. lotus, and, N. heudelotii. Nymphaea lotus displays wider distribution in West, East, and parts of South African countries including their coastlines compared to all other species. Nymphaea nouchali indicates dense distribution in countries South of Africa while N. micrantha and N. heudelotii in West African countries. Greater habitat changes were noticed between the future and the past projection due to limited range expansion in 2.6, 4.5, and 8.5 (2050) Representative Concentration Pathways (RCPs) in almost all species. The species' suitable habitat distribution was mainly influenced by nine variables, mostly the temperature and precipitation variables. This study provides projections of future climatic scenarios potentially influencing the distribution of Nymphaea species in Africa, which may be useful for the ongoing conservation and management of these plants especially in areas loosing suitable climatic conditions. [ABSTRACT FROM AUTHOR]

• Genetic structure was assessed using seven polymorphic SSR markers. • High genetic diversity and the absence of a spatial genetic structuring were detected. • Ecoregion differences might not be responsible for the diversity within Ottelia ulvifolia. • Floodplains and river systems connectivity were likely to contribute to the high gene flow among populations. As vital components of freshwater ecosystems, river systems directly boost the dispersal and gene flow of aquatic species. However, various river systems might also increase the potential for isolation of these species and their genetic differentiation. In Africa, the roles of river systems in shaping the genetic diversity and structures of aquatic species are still poorly studied. In order to assess the influence of river systems in freshwater ecoregions on the genetic variation of Ottelia ulvifolia , we genotyped 307 individuals of 18 populations from Bangweulu-Mweru, Middle Zambezi-Luangwa, and Upper Zambezi Floodplain ecoregions in Zambia using ten microsatellite markers. Our results revealed an overall high genetic diversity (H E = 0.475) and high gene flow (Nm > 1) among the three ecoregions. Notably, a relatively higher diversity (H E = 0.485; I = 0.836) was detected in Bangweulu-Mweru compared to those other ecoregions, which could be contributed by frequent river capture events in the area. STRUCTURE, TESS, PCoA, and NJ analyses identified two distinct clusters that were further divided into five sub-clusters, three in bisexual populations and two in the unisexual populations, respectively. The lower genetic differentiation among 18 populations (Fst = 0.258) in the present study could be attributed to the frequent hybridization among populations via insect pollination and water-mediated seed dispersal. A significant positive correlation between Jost's D/(1-Jost's D) and geographic distance among populations (r = 0.142, P = 0.050) indicated deviation for mutation-drift equilibrium. The current findings, however, do not support the hypothesis that variations within ecoregions drive the genetic variation and population structure of O. ulvifolia in Zambia. Lastly, habitat specialization and floral characteristics are examples of behavioral factors that may promote a genetic difference in O. ulvifolia. Our study provides general knowledge of the genetic variation of O. ulvifolia in tropical Africa and indicates a possible regional alteration of various macrophyte dispersal mechanisms at a vast geographic scale, therefore encouraging the need for further research on the genus. [ABSTRACT FROM AUTHOR]