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We explore the legalization of the cannabis industry in the US, and point at the conflicted path through which this emerging industry has traversed. In particular, we highlight how this industry has navigated controversy to become one of the fastest growing industries in the world. The paper also offers a theoretical model that explains the role played by social movements to propel and shape early antagonism towards increasing protagonism. Evidence of the latter is seen in the form of cannabis laws passing at the state level in the US. We posit that resource mobilization and shaping effects were instrumental in laying the grounds for legalization. A detailed timeline of the legalization for over one and a half centuries (from 1840 to 2019) is also provided. Our synergistic approach integrates a historical perspective with social movement theory to address a relatively new and under examined phenomenon in the emerging US legal cannabis industry and ensuing ethical implications. [ABSTRACT FROM AUTHOR]

Plants and their specialized flower visitors provide valuable insights into the evolutionary consequences of species interactions. In particular, antagonistic interactions between insects and plants have often been invoked as a major driver of diversification. Here we use a tropical community of palms and their specialized insect flower visitors to test whether antagonisms lead to higher population divergence. Interactions between palms and the insects visiting their flowers range from brood pollination to florivory and commensalism, with the latter being species that feed on decaying–and presumably undefended–plant tissues. We test the role of insect-host interactions in the early stages of diversification of nine species of beetles sharing host plants and geographical ranges by first delimiting cryptic species and then using models of genetic isolation by environment. The degree to which insect populations are structured by the genetic divergence of plant populations varies. A hierarchical model reveals that this variation is largely uncorrelated with the kind of interaction, showing that antagonistic interactions are not associated with higher genetic differentiation. Other aspects of host use that affect plant-associated insects regardless of the outcomes of their interactions, such as sensory biases, are likely more general drivers of insect population divergence. de Medeiros and Farrell test how insect-host interactions influence species divergence in phytophagous insects. Using ddRAD-seq data and hierarchical modelling, they demonstrate, surprisingly, that antagonistic interactions between insect and host do not lead to greater species diversification. [ABSTRACT FROM AUTHOR]

Northeast India is amongst the 34 Biodiversity Hot Spots of the world with large number of unexplored flora and fauna. A total of 74 potential isolates with probiotic properties were isolated from Oecophylla smaragdina, an edible insect used by local tribes as a nutritious medicinal food source out of which, the most potential probiotic candidate was identified as Bacillus sp. PD6 by 16S rRNA sequencing. Cell surface trait analysis shows hydrophobicity and auto-aggregation percentage of 46.2 ± 0.32% and 61.41 ± 0.28% respectively. The cell free extract (CFE) of the isolate shows the presence of essential amino acids viz, lysine, valine, leucine, isoleucine, and threonine indicating its nutritional value. It survives significantly at pH range from 1 to 10 and capable of hydrolyzing bile salt. The CFE shows antagonistic effect against B. cereus ATCC 11778, E. coli ATCC 25922 and L. monocytogenes ATCC BAA751. FTIR spectra of bacterial exo-polysaccharide shows the presence of νC=C-H stretch, νN-H stretch, νC-H stretch, νC-H bending and νC=O stretch bonds. It was found to be non-cytotoxic against primary mouse liver cell line and sheep erythrocytes and also, sensitive against wide range of broad and narrow spectrum antibiotics making it recommendable for human consumption. [ABSTRACT FROM AUTHOR]

A salient feature of the insect olfactory system is its ability to detect and interpret simultaneously the identity and concentration of an odorant signal along with the temporal stimulus cues that are essential for accurate odorant tracking. The olfactory system of the cockroach utilizes two parallel pathways for encoding of odorant identity and the moment-to-moment succession of odorant concentrations as well as the rate at which concentration changes. This separation originates at the peripheral level of the ORNs (olfactory receptor neurons) which are localized in basiconic and trichoid sensilla. The graded activity of ORNs in the basiconic sensilla provides the variable for the combinatorial representation of odorant identity. The antagonistically responding ON and OFF ORNs in the trichoid sensilla transmit information about concentration increments and decrements with excitatory signals. Each ON and OFF ORN adjusts its gain for odorant concentration and its rate of change to the temporal dynamics of the odorant signal: as the rate of change diminishes, both ORNs improve their sensitivity for the rate of change at the expense of the sensitivity for the instantaneous concentration. This suggests that the ON and OFF ORNs are optimized to detect minute fluctuations or even creeping changes in odorant concentration. [ABSTRACT FROM AUTHOR]

Bacterial fish pathogens are pervasive in aquaculture. Control of bacterial fish pathogen is a difficult task among aquaculture practitioners. A large number of antibiotics are used for the control of prevalent bacterial pathogens in aquaculture. This may lead to drug resistance among pathogens and further treatment will be ineffective. Here, we can use probiotic bacteria as a biocontrol agent in fish disease and it is a novel field. In this study, antimicrobial potential of the bacterium Bacillus coagulans (MTCC-9872) has been evaluated through in vitro antagonistic activity of cellular preparations/components against potent pathogens. The cellular preparations/components such as Ethyl acetate extract, whole-cell product, heat-killed whole-cell product, and filtered broth were exhibited bactericidal activity against the tested pathogens. Bactericidal activity varied among different cellular preparation/components. The tested bacterium effectively produced biofilm as significant as tested positive control in a microtitre plate and effectively adhered on to the glass slide. In addition, the bacterium was capable of producing extracellular enzymes necessary for the digestion of food materials and was capable to grow in fish mucus from Oreochromis niloticus. The bacterium tolerated bile juice secreted by the host. Moreover, intraperitoneal injection of the bacterium did not induce any pathological signs, symptoms or mortalities in Oreochromis niloticus and revealed the safety of this bacterium in the fish. [ABSTRACT FROM AUTHOR]

Background and aims: Plants influence the soil they grow in, and this can alter the performance of other, later growing plants in the same soil. This is called plant-soil feedback and is usually tested with monospecific soils, i.e. soils that are conditioned by one plant species. Here, we test if plant-soil feedbacks of inocula consisting of mixtures of monospecific soils can be predicted from the effects of the component inocula.Methods: Chrysanthemum plants were grown in sterile soil inoculated with eight monospecific conditioned soils and with mixtures consisting of all pairwise combinations. Plant biomass and leaf yellowness were measured and the additivity was calculated.Results: On average, plant biomass in the mixed inocula was slightly but significantly (6%) lower than predicted. In contrast, when growing in mixed inocula, plants showed 38% less disease symptoms than predicted. Moreover, the larger the difference between the effects of the two monospecific soils on plant growth, the higher the observed effect in the mixture exceeded the predicted effects.Conclusions: We show that mixed monospecific soils interact antagonistically in terms of plant growth, but synergistically for disease symptoms. Our study further advances our understanding of plant-soil feedbacks, and suggests that mixing soils can be a powerful tool to steer soil microbiomes to improve plant-soil feedback effects. [ABSTRACT FROM AUTHOR]

Interactions among members of microbial consortia drive the complex dynamics in soil, gut, and biotechnology microbiomes. Proteomic analysis of defined co-cultures of well-characterized species provides valuable information about microbial interactions. We used a label-free approach to quantify the responses to co-culture of two model bacterial species relevant to soil and rhizosphere ecology, Bacillus atrophaeus and Pseudomonas putida. Experiments determined the ratio of species in co-culture that would result in the greatest number of high-confidence protein identifications for both species. The 281 and 256 proteins with significant shifts in abundance for B. atrophaeus and P. putida, respectively, indicated responses to co-culture in overall metabolism, cell motility, and response to antagonistic compounds. Proteins associated with a virulent phenotype during surface-associated growth were significantly more abundant for P. putida in co-culture. Co-culture on agar plates triggered a filamentous phenotype in P. putida and avoidance of P. putida by B. atrophaeus colonies, corroborating antagonistic interactions between these species. Additional experiments showing increased relative abundance of P. putida under conditions of iron or zinc limitation and increased relative abundance of B. atrophaeus under magnesium limitation were consistent with patterns of changes in abundance of metal-binding proteins during co-culture. These results provide details on the nature of interactions between two species with antagonistic capabilities. Significant challenges remaining for the development of proteomics as a tool in microbial ecology include accurate quantification of low-abundance peptides, especially from rare species present at low relative abundance in a consortium. [ABSTRACT FROM AUTHOR]

Characterization of interactions within a host-associated microbiome can help elucidate the mechanisms of microbial community formation on hosts and can be used to identify potential probiotics that protect hosts from pathogens. Microbes employ various modes of antagonism when interacting with other members of the community. The formation of biofilm by some strains can be a defense against antimicrobial compounds produced by other taxa. We characterized the magnitude of antagonistic interactions and biofilm formation of 25 phylogenetically diverse taxa that are representative of isolates obtained from egg surfaces of the threatened fish species lake sturgeon ( Acipenser fulvescens) at two ecologically relevant temperature regimes. Eight isolates exhibited aggression to at least one other isolate. Pseudomonas sp. C22 was found to be the most aggressive strain, while Flavobacterium spp. were found to be one of the least aggressive and the most susceptible genera. Temperature affected the prevalence and intensity of antagonism. The aggressive strains identified also inhibited growth of known fish pathogens. Biofilm formations were observed for nine isolates and were dependent on temperature and growth medium. The most aggressive of the isolates disrupted biofilm formation of two well-characterized isolates but enhanced biofilm formation of a fish pathogen. Our results revealed the complex nature of interactions among members of an egg associated microbial community yet underscored the potential of specific microbial populations as host probiotics. [ABSTRACT FROM AUTHOR]

The relationship between feminism and metaphysics has historically been strained. Metaphysics has until recently remained dismissive of feminist insights, and many feminist philosophers have been deeply skeptical about any value that metaphysics might have when thinking about advancing gender justice. Nevertheless, feminist philosophers have in recent years increasingly taken up explicitly metaphysical investigations. Such feminist investigations have expanded the scope of metaphysics in holding that metaphysical tools can help advance debates on topics outside of traditional metaphysical inquiry (e.g. the nature of gender, sex, or sexuality). Moreover, feminist philosophers typically bring new methodological insights to bear on traditional ways of doing philosophy. Feminist metaphysicians have also recently begun interrogating the methods of metaphysics and they have raised questions about what metaphysics as a discipline is in the business of doing. In discussing such methodological issues, Elizabeth Barnes has recently argued that some prevalent conceptions of metaphysics rule out feminist metaphysics from the start and render it impossible. This is bad news for self-proclaimed feminist metaphysicians in suggesting that they are mistaken about the metaphysical status of their work. With this worry in mind, the paper asks: how does feminist metaphysics fare relative to 'mainstream' metaphysics? More specifically, it explores how feminist and 'mainstream' debates intersect, on what grounds do they come apart (if at all), and whether feminist metaphysics qualifies as metaphysics 'proper'. [ABSTRACT FROM AUTHOR]

In this study, we determined the competition effects of herbaceous vegetation on survival, growth, and plant water relations of planted lenga ( Nothofagus pumilio) seedlings under field and nursery conditions in western Patagonia, Argentina. In the field, thirty (1.5 × 1.5 m) plots were randomly set in a grazing-free exclosure built in a typical grazing-degraded lenga canopy gap mainly colonized by non-native herbs and grasses ( empastado). Herbaceous aerial and root biomass was removed in half of the plots (non-competition treatment, NCT), while the others (competition treatment, CT), remained undisturbed. Four similarly-sized lenga seedlings were planted per plot. In the nursery, 120 lenga seedlings were planted in individual pots containing soil of the field study site, and set to a factorial experiment including two competition levels (CT and NCT) and two watering regimes: normal (simulating average rains during the growing season, 500 mm, NW), and high (equivalent to 1000 mm, HW). During three growing seasons, we determined seedling survival, growth, and plant and soil water status of both experiments. Higher survival and growth, and better plant water status values were obtained in NCT as compared to CT in both experiments. In the nursery, HW did not improve survival and growth as compared to NW. In restoration trials implying grazing-degraded areas, increases in lenga seedling survival and growth could be achieved by reducing nearby competition of grasses and herbs, while extra watering appears unnecessary. However, limitations in the experimental design (pseudo-replication), limits generalization of results to other forest ecosystems with similar structural and functional characteristics. [ABSTRACT FROM AUTHOR]

Open range grazing by cattle is common on heterogeneous montane landscapes in western Canada. These areas are often jointly managed for forestry, leading to concerns over forest re-establishment following clear cut harvest and cattle impacts on tree regeneration. A network of 154 field plots were used to examine cattle utilization across five coniferous cut blocks within three large pastures of SW Alberta over a 2 year period. Specific objectives were to: (1) quantify cattle presence across cut blocks under free-choice conditions; (2) identify the environmental factors responsible for observed patterns of cattle presence, including topography, distance to water, forage characteristics and slash properties; and (3) document cattle impact on conifer seedlings. Averaged over 2 years, evidence of cattle was found in 46 % of plots, primarily as herbage removal. Cattle presence across logged areas was associated with plots at lower elevations and closer to water, and to a lesser extent, those areas with greater forage biomass but lower quality. Forest surveys done 3 years after harvest indicated most tree regeneration consisted of planted lodgepole pine ( Pinus contorta Loudon) and naturally regenerating Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco). While regeneration among plots remained below the provincial requirement of 80 % stocking, ranging from 68 to 77 % among cut blocks, this deficit was not attributed to cattle impact, as only two tree seedlings surveyed had evidence of livestock-induced damage. Finally, cattle visitation to plots was lower with taller slash in select pastures, suggesting slash may deter cattle use of some cut blocks. Overall, the results of this study support the notion that forest management and cattle grazing are compatible uses on Montane landscapes managed for multiple purposes. [ABSTRACT FROM AUTHOR]

Background and aims: Cadmium (Cd) is a heavy metal that is highly toxic to organisms. Studies have shown that an increasing Fe supply decreases Cd accumulation in plants. In this study, we investigated the mechanism underlying the effect of Fe on Cd uptake. Methods: We compared the effects of Fe application on Cd levels in wild-type Arabidopsis thaliana Col-0 and IRT1-null mutant irt1 (loss in function of Fe uptake). Results: In the Fe-Cd alternative rotation treatment, which ensured asynchronous uptake of Fe and Cd, the irt1 mutants had a lower Cd level than the Col-0 plants. In addition, an increase in the Fe supply decreased the Cd level in Col-0 plants, accompanied by an inhibition of IRT1 expression in roots. Furthermore, both Col-0 and irt1 plants grown in Fe-Cd alternative rotation treatment, showed higher Cd uptake than those grown in another rotation treatment, which allowed synchronous uptake of Fe and Cd. Nevertheless, the differences in Cd uptake between the two rotation treatments were greater in Col-0 plants than in irt1 mutants. Conclusions: Inhibition of IRT1-mediated Cd uptake and enhancement of antagonism between Fe and Cd uptake are two mechanisms involved in the inhibition of Cd uptake by Fe supply. [ABSTRACT FROM AUTHOR]

One of the major diseases affecting Hevea brasiliensis is the white root rot caused by the fungus Rigidoporus microporus. Current treatment measures taken to control rubber diseases are highly dependent on chemical fungicides which pollute the environment and pose health hazards to workers. The utilisation of chitinolytic microorganisms for disease control is an attractive alternative. A total of 61 chitinolytic isolates were isolated from soil and tested for antagonism against R. microporus using dual culture assay. Out of the 61 chitinolytic microorganisms, 46 exhibited inhibition against R. microporus ranging from 3.67% to 85.65% with isolate SPSB 4-4 recording the highest percentage inhibition. Light microscopy observation revealed degradation of mycelium implying the hydrolysis offungal cell wall by chitinase. Nine chitinolytic microorganisms which exhibited the highest percent inhibition were selected for dipped stick inhibition assay. All nine isolates inhibited the growth o/R. microporus with percent inhibition ranging from 31.69% to 91.63% with isolate SPSB 4-4 exhibiting the highest percent inhibition. These nine isolates were sent for 16S rRNA gene sequencing for bacterial identification. The isolates were identified to be from the genus Pseudomonas, Burkholderia and Streptomyces. These chitinolytic microorganisms hold great potential to be developed as effective, environmentally friendly and worker-safe solution for crop protection. [ABSTRACT FROM AUTHOR]

Brown-headed cowbirds ( Molothrus ater) deposit their eggs into the nests of other birds, which then raise the cowbird chick. Female cowbirds thus have limited options for impacting their offspring's development via maternal effects compared to most other passerines. Cowbirds can impact their offspring's phenotype by choosing among potential host nests, and by adjusting egg resources based on host characteristics. To examine whether cowbirds exhibit either or both of these strategies, we investigated rates of cowbird parasitism and egg investment (egg size, yolk-to-albumen ratio, and yolk testosterone and androstenedione) among and within host species in a shrubland bird community. We found that the probability of being parasitized by cowbirds, controlling for host status as a cowbird egg accepter or rejecter and ordinal date, varied significantly among host species, indicating an apparent preference for some hosts. Parasitism rates did not differ with host size, however, and despite variation in cowbird egg size among host species, this variation was not related to host size or cowbird preference. Among host species with eggs that are larger than those of the cowbird, cowbirds were significantly more likely to parasitize nests with relatively smaller eggs, whereas parasitism rates did not vary with relative egg size in host species with smaller eggs. There was no evidence for variation in cowbird egg components among or within host species. Our data indicate that cowbirds discriminate among host nests, but do not appear to adjust the composition of their eggs based on inter- or intraspecific host variation. [ABSTRACT FROM AUTHOR]

The complexity of behavioural interactions in predator-prey systems has recently begun to capture trait-effects, or non-lethal effects, of predators on prey via induced behavioural changes. Non-lethal predation effects play crucial roles in shaping population and community dynamics, particularly by inducing changes to foraging, movement and reproductive behaviours of prey. Prey exhibit trade-offs in behaviours while minimizing predation risk. We use a novel evolutionary ecosystem simulation EcoSim to study such behavioural interactions and their effects on prey populations, thereby addressing the need for integrating multiple layers of complexity in behavioural ecology. EcoSim allows complex intra- and inter-specific interactions between behaviourally and genetically unique individuals called predators and prey, as well as complex predator-prey dynamics and coevolution in a tri-trophic and spatially heterogeneous world. We investigated the effects of predation risk on prey energy budgets and fitness. Results revealed that energy budgets, life history traits, allocation of energy to movements and fitness-related actions differed greatly between prey subjected to low-predation risk and high-predation risk. High-predation risk suppressed prey foraging activity, increased total movement and decreased reproduction relative to low-risk. We show that predation risk alone induces behavioural changes in prey which drastically affect population and community dynamics, and when interpreted within the evolutionary context of our simulation indicate that genetic changes accompanying coevolution have long-term effects on prey adaptability to the absence of predators. [ABSTRACT FROM AUTHOR]

Many competitive communities exhibit a puzzling amount of species diversity. In this study, we model a community of symmetric competitors in a fluctuating environment. We use biologically realistic temperature-dependent growth curves with a widely hypothesized trade-off between maximum growth and nice breadth to control the shapes of the curves of different species. We perform three analyses of the community dynamics to investigate the role of environmental fluctuations in community composition and species diversity. We initiate communities with equal abundances of all species and randomize the temperature fluctuations so that there is no correlation between species responses, only noise. We initiate single populations and allow other species to randomly invade the community. We also knock out extant species one by one from an established community and allow them to reinvade after the remaining species have adjusted. We find that competitors with sufficiently different temperature niches coexist via temporal niche differentiation. We also find long-term persistence of species that are very similar to a dominant competitor. This creates communities with species clumped along a temperature niche axis, with stable coexistence between groups and near neutrality within groups. The near neutrality results in interspecific synchrony within the groups, providing an explanation for the maintenance of high diversity in competitive communities where synchrony is commonly observed. [ABSTRACT FROM AUTHOR]

Toxicity and morphology may function as defense mechanisms of bloom-forming cyanobacteria against zooplankton grazing. Yet, the relative importance of each of these factors and their plasticity remains poorly known. We tested the effects of chemical and morphological traits of the bloom-forming cyanobacterium Cylindrospermopsis raciborskii on the feeding response of the selective feeder Eudiaptomus gracilis (Calanoida, Copepoda), using a saxitoxin-producing strain (STX+) and a non-saxitoxin (STX−)-producing strain as food. From these two chemotypes, we established cultures of three different morphotypes that differed in filament length (short, medium, and long) by incubating the strains at 17, 25, and 32 °C. We hypothesized that the inhibitory effects of saxitoxins determine the avoidance of C. raciborskii, and that morphology would only become relevant in the absence of saxitoxins. Temperature affected two traits: higher temperature resulted in significantly shorter filaments in both strains and led to much higher toxin contents in the STX+ strain (1.7 μg eq STX L at 17 °C, 7.9 μg eq STX L at 25 °C, and 25.1 μg eq STX L at 32 °C). Copepods strongly reduced the ingestion of the STX+ strain in comparison with STX− cultures, regardless of filament length. Conversely, consumption of shorter filaments was significantly higher in the STX− strain. The great plasticity of morphological and chemical traits of C. raciborskii and their resultant contrasting effects on the feeding behavior of zooplankton might explain the success of this cyanobacterium in a variety of aquatic environments. [ABSTRACT FROM AUTHOR]

European Stone Fruit Yellows (ESFY) is an emerging disease caused by ' Candidatus Phytoplasma prunorum' (' Ca. P. prunorum') affecting stone fruits, as apricots. Resistant apricot cultivars are unknown, but it has been demonstrated that individual plants can recover from the disease, behaving as completely tolerant to ESFY. The status of tolerance is transmissible by grafting to successive apricot individuals, but it is not clear whether recovery corresponds to a transmissible tolerance that depends on a plant-mediated reaction or if it is due to a cross-protection promoted by a transmissible protective agent i.e. hypovirulent strain/s of ' Ca. P. prunorum'. Results achieved after prolonged field experiments support the first hypothesis. Two groups of apricot plants derived from a common recovered mother (one ' Ca. P. prunorum'-free after heat-treatment and the second not heat-treated, i.e. harbouring potential protective strain/s of the phytoplasma), behaved similarly: no plants from either of the two groups developed stable ESFY symptoms after natural infections. Corresponding groups of plants, derived from symptomatic mothers, developed a high percentage of diseased plants after natural infection. No potential protective ' Ca. P. prunorum' hypovirulent strains were detected in the asymptomatic apricot plants. The summarized evidence supports a host-defence induction, likely of epigenetic feature. The present long-term study in apricot represents an uncommon empiric proof supporting the theory of inducible resistance to pathogens in plants. [ABSTRACT FROM AUTHOR]

Indirect interactions among species emerge from the complexity of ecological networks and can strongly affect the response of communities to disturbances. To determine these indirect interactions and understand better community dynamics, ecologists focused on the interactions within small sets of species or modules. Thanks to their analytical tractability, modules bring insights on the mechanisms occurring in complex interaction networks. So far, most studies have considered modules with a single type of interaction although numerous species are involved in mutualistic and antagonistic interactions simultaneously. In this study, we analyse the dynamics of a diamond-shaped module with multiple interaction types: two resource species sharing a mutualist and a consumer. We describe the different types of indirect interaction occurring between the resource species and the conditions for a stable coexistence of all species. We show that the nature of indirect interactions between resource species (i.e. apparent facilitation, competition or antagonism), as well as stable coexistence, depend on the species generalism and asymmetry of interactions, or in other words, on the distribution of interaction strengths among species. We further unveil that a balance between mutualistic and antagonistic interactions at the level of resource species favours stable coexistence, and that species are more likely to coexist stably if there is apparent facilitation between the two resource species rather than apparent competition. Our results echo existing knowledge on the trophic diamond-shaped module, and confirm that our understanding of communities combining different interaction types can gain from module analyses. [ABSTRACT FROM AUTHOR]

There is a strong trend of declining populations in many species of both animals and plants. Dwindling numbers of species can eventually lead to their functional extinction. Functional, or ecological, extinction occurs when a species becomes too rare to fulfill its ecological, interactive role in the ecosystem, leading to true (numerical) extinction of other depending species. Recent theoretical work on food webs suggests that the frequency of functional extinction might be surprisingly high. However, little is known about the risk of functional species extinctions in networks with other types of interactions than trophic ones. Here, we explore the frequency of functional extinctions in model ecological networks having different proportions of antagonistic and mutualistic links. Furthermore, we investigate the topological relationship between functionally and numerically extinct species. We find that (1) the frequency of functional extinctions is higher in networks containing a mixture of antagonistic and mutualistic interactions than in networks with only one type of interaction, (2) increased mortality rate of species having both mutualistic and antagonistic links is more likely to lead to extinction of another species than to extinction of the species itself compared to species having only mutualistic or antagonistic links, and (3) trophic distance (shortest path) between functionally and numerically extinct species is, on average, longer than one, indicating the importance of indirect effects. These results generalize the findings of an earlier study on food webs, demonstrating the potential importance of functional extinction in a variety of ecological network types. [ABSTRACT FROM AUTHOR]

Interactions between flowers and their visitors span the spectrum from mutualism to antagonism. The literature is rich in studies focusing on mutualism, but nectar robbery has mostly been investigated using phytocentric approaches focused on only a few plant species. To fill this gap, we studied the interactions between a nectar-robbing hermit hummingbird, Phaethornis ruber, and the array of flowers it visits. First, based on a literature review of the interactions involving P. ruber, we characterized the association of floral larceny to floral phenotype. We then experimentally examined the effects of nectar robbing on nectar standing crop and number of visits of the pollinators to the flowers of Canna paniculata. Finally, we asked whether the incorporation of illegitimate interactions into the analysis affects plant-hummingbird network structure. We identified 97 plant species visited by P. ruber and found that P. ruber engaged in floral larceny in almost 30 % of these species. Nectar robbery was especially common in flowers with longer corolla. In terms of the effect on C. paniculata, the depletion of nectar due to robbery by P. ruber was associated with decreased visitation rates of legitimate pollinators. At the community level, the inclusion of the illegitimate visits of P. ruber resulted in modifications of how modules within the network were organized, notably giving rise to a new module consisting of P. ruber and mostly robbed flowers. However, although illegitimate visits constituted approximately 9 % of all interactions in the network, changes in nestedness, modularity, and network-level specialization were minor. Our results indicate that although a flower robber may have a strong effect on the pollination of a particular plant species, the inclusion of its illegitimate interactions has limited capacity to change overall network structure. [ABSTRACT FROM AUTHOR]

Obstructive sleep apnoea (OSA) is highly prevalent in hypertensive patients, particularly those with drug resistance. Evidence from animal experiments, epidemiologic studies and clinical trials strongly suggest a causal link. Mechanistic studies argue for increased sympathetic neural activity and endothelial dysfunction. However, disturbances in fluid volume regulation and distribution may also be involved in the pathogenesis of these two conditions. Several studies have shown a high prevalence of OSA in fluid-retaining states including hypertension, a direct relationship between the severity of OSA and the volume of fluid displaced from the legs to the neck during sleep, and a decrease in upper airway cross-sectional area in response to graded lower body positive pressure. Treatments targeting fluid retention and redistribution, including diuretics, mineralocorticoid antagonists, exercise, and possibly renal denervation lower blood pressure and reduce the apnoea-hypopnoea index, a measure of OSA severity. From these observations, it has been postulated that during the daytime, excess fluid collects in the lower extremities due to gravity, and on lying down overnight is redistributed rostrally to the neck, where it may narrow the upper airway and increase its collapsibility, predisposing to OSA when pharyngeal dilator muscle activity decreases during sleep. This article discusses the associations between OSA and hypertension and reviews the evidence for fluid accumulation and its nocturnal rostral redistribution in the pathogenesis of OSA in hypertensive patients. [ABSTRACT FROM AUTHOR]

A total of 53 Wickerhamomyces anomalus strains were examined for antagonistic activity, including the nomenclature types of the species with the names presently considered synonymous. Over 70% of the strains exhibited antibiotic activity. According to the action spectra of intraspecific activity, the strains fell into three groups, while according to their activity against other Wickerhamomyces species and phylogenetically related Candida species they formed five subgroups. Antibiotic agents (mostly mycocins) varied in their physicochemical properties [ABSTRACT FROM AUTHOR]

Transgenic crop pyramids producing two or more Bacillus thuringiensis (Bt) toxins that kill the same insect pest have been widely used to delay evolution of pest resistance. To assess the potential of pyramids to achieve this goal, we analyze data from 38 studies that report effects of ten Bt toxins used in transgenic crops against 15 insect pests. We find that compared with optimal low levels of insect survival, survival on currently used pyramids is often higher for both susceptible insects and insects resistant to one of the toxins in the pyramid. Furthermore, we find that cross-resistance and antagonism between toxins used in pyramids are common, and that these problems are associated with the similarity of the amino acid sequences of domains II and III of the toxins, respectively. This analysis should assist in future pyramid design and the development of sustainable resistance management strategies. [ABSTRACT FROM AUTHOR]

In two experiments, using a modified task-cueing paradigm, participants switched among a set of four tasks that was on some trials reduced to two by a pre-cue preceding the task cue. A pre-cue temporarily restricting the options to two candidate tasks facilitated performance on switch trials to a much larger extent than on repeat trials. This observation is interpreted as an indication of a short-term restructuring of a global task representation by implementing antagonistic constraints among the representations of the two remaining candidate tasks. [ABSTRACT FROM AUTHOR]

Multispecies biofilms are predominant in almost all natural environments, where myriads of resident microorganisms interact with each other in both synergistic and antagonistic manners. The interspecies interactions among different bacteria are, despite the ubiquity of these communities, still poorly understood. Here, we report a rapid, reproducible and sensitive approach for quantitative screening of biofilm formation by bacteria when cultivated as mono- and multispecies biofilms, based on the Nunc-TSP lid system and crystal violet staining. The relative proportion of the individual species in a four-species biofilm was assessed using quantitative PCR based on SYBR Green I fluorescence with specific primers. The results indicated strong synergistic interactions in a four-species biofilm model community with a more than 3-fold increase in biofilm formation and demonstrated the strong dominance of two strains, Xanthomonas retroflexus and Paenibacillus amylolyticus. The developed approach can be used as a standard procedure for evaluating interspecies interactions in defined microbial communities. This will be of significant value in the quantitative study of the microbial composition of multispecies biofilms both in natural environments and infectious diseases to increase our understanding of the mechanisms that underlie cooperation, competition and fitness of individual species in mixed-species biofilms. [ABSTRACT FROM AUTHOR]

The distribution of 14 elements (both essential and non-essential) in the Hass and Fuerte cultivars of avocados grown at six different sites in KwaZulu-Natal, South Africa, was investigated. Soils from the different sites were concurrently analysed for elemental concentration (both total and exchangeable), pH, organic matter and cation exchange capacity. In both varieties of the fruit, concentrations of the elements Cd, Co, Cr, Pb and Se were extremely low with the other elements being in decreasing order of Mg > Ca > Fe > Al > Zn > Mn > Cu > Ni > As. Nutritionally, avocados were found to be a good dietary source of the micronutrients Cu and Mn. In soil, Pb concentrations indicated enrichment (positive geoaccumuluation indices) but this did not influence uptake of the metal by the plant. Statistical analysis was done to evaluate the impact of soil quality parameters on the nutrient composition of the fruits. This analysis indicated the prevalence of complex metal interactions at the soil-plant interface that influenced their uptake by the plant. However, the plant invariably controlled metal uptake according to metabolic needs as evidenced by their accumulation and exclusion. [ABSTRACT FROM AUTHOR]

In the biosphere, many species live in close proximity and can thus interact in many different ways. Such interactions are dynamic and fall along a continuum between antagonism and cooperation. Because interspecies interactions are the key to understanding biological communities, it is important to know how species interactions arise and evolve. Here, we show that the feedback between ecological and evolutionary processes has a fundamental role in the emergence and dynamics of species interaction. Using a two-species artificial community, we demonstrate that ecological processes and rapid evolution interact to influence the dynamics of the symbiosis between a eukaryote (Saccharomyces cerevisiae) and a bacterium (Rhizobium etli). The simplicity of our experimental design enables an explicit statement of causality. The niche-constructing activities of the fungus were the key ecological process: it allowed the establishment of a commensal relationship that switched to ammensalism and provided the selective conditions necessary for the adaptive evolution of the bacteria. In this latter state, the bacterial population radiates into more than five genotypes that vary with respect to nutrient transport, metabolic strategies and global regulation. Evolutionary diversification of the bacterial populations has strong effects on the community; the nature of interaction subsequently switches from ammensalism to antagonism where bacteria promote yeast extinction. Our results demonstrate the importance of the evolution-to-ecology pathway in the persistence of interactions and the stability of communities. Thus, eco-evolutionary dynamics have the potential to transform the structure and functioning of ecosystems. Our results suggest that these dynamics should be considered to improve our understanding of beneficial and detrimental host-microbe interactions. [ABSTRACT FROM AUTHOR]

Although mutualisms are ubiquitous in nature, our understanding of the potential impacts of climate change on these important ecological interactions is deficient. Here, we report on a thermal stress-related shift from cooperation to antagonism between members of a mutualistic coral-dwelling community. Increased mortality of coral-defending crustacean symbionts Trapezia cymodoce (coral crab) and Alpheus lottini (snapping shrimp) was observed in response to experimentally elevated temperatures and reduced coral-host ( Pocillopora damicornis) condition. However, strong differential numerical effects occurred among crustaceans as a function of species and sex, with shrimp (75 %), and female crabs (55 %), exhibiting the fastest and greatest declines in numbers. These declines were due to forceful eviction from the coral-host by male crabs. Furthermore, surviving female crabs were impacted by a dramatic decline (85 %) in egg production, which could have deleterious consequences for population sustainability. Our results suggest that elevated temperature switches the fundamental nature of this interaction from cooperation to competition, leading to asymmetrical effects on species and/or sexes. Our study illustrates the importance of evaluating not only individual responses to climate change, but also potentially fragile interactions within and among susceptible species. [ABSTRACT FROM AUTHOR]

The 1968 Spainhower Commission planned extensive changes in the organization of public education in Missouri, proposing larger, comprehensive districts throughout the state. Intended to increase efficiency and reduce inequities, its reform proposals spurred widespread opposition from both rural and suburban communities. In the suburbs hostility was particularly vehement and often was expressed in racial terms, revealing fault lines that came to divide large metropolitan regions in the 1960s. There were differences in the response of suburbanites in Kansas City and St. Louis, however, as resistance was expressed more adamantly in greater Kansas City. In St. Louis, a local tradition of holding meetings to discuss educational problems and inter-district cooperation appears to have helped mediate opposition to the suggestion of change. Eventually districts in greater St. Louis participated in an extensive transfer plan for urban students, while districts in metro Kansas City did not. Despite these differences, suburban residents' antagonism in both areas toward plans for sending significant numbers of urban students to their schools remains quite high today, suggesting that patterns of conflict revealed in the Spainhower era continue to exist. [ABSTRACT FROM AUTHOR]

Edaphic factors can lead to differences in plant morphology and tissue chemistry. However, whether these differences result in altered plant–insect interactions for soil-generalist plants is less understood. We present evidence that soil chemistry can alter plant–insect interactions both directly, through chemical composition of plant tissue, and indirectly, through plant morphology, for serpentine-tolerant Mimulus guttatus (Phrymaceae). First, we scored floral display (corolla width, number of open flowers per inflorescence, and inflorescence height), flower chemistry, pollinator visitation and florivory of M. guttatus growing on natural serpentine and non-serpentine soil over 2 years. Second, we conducted a common garden reciprocal soil transplant experiment to isolate the effect of serpentine soil on floral display traits and flower chemistry. And last, we observed arrays of field-collected inflorescences and potted plants to determine the effect of soil environment in the field on pollinator visitation and florivore damage, respectively. For both natural and experimental plants, serpentine soil caused reductions in floral display and directly altered flower tissue chemistry. Plants in natural serpentine populations received fewer pollinator visits and less damage by florivores relative to non-serpentine plants. In experimental arrays, soil environment did not influence pollinator visitation (though larger flowers were visited more frequently), but did alter florivore damage, with serpentine-grown plants receiving less damage. Our results demonstrate that the soil environment can directly and indirectly affect plant–mutualist and plant–antagonist interactions of serpentine-tolerant plants by altering flower chemistry and floral display. [ABSTRACT FROM AUTHOR]

Both ecological and evolutionary timescales are of importance when considering an ecological system; population dynamics affect the evolution of species traits, and vice versa. Recently, these two timescales have been used to explain structural patterns in host-parasite networks, where the evolution of the manner in which species balance the use of their resources in interactions with each other was examined. One of these patterns was nestedness, in which the set of parasite species within a particular host forms a subset of those within a more species-rich host. Patterns of both nestedness and anti-nestedness have been observed significantly more often than expected due to chance in host-parasite networks. In contrast, mutualistic networks tend to display a significant degree of nestedness, but are rarely anti-nested. Within networks with different interaction types, therefore, there appears to be a feature promoting non-random structural patterns, such as nestedness and anti-nestedness, depending on the interaction types involved. Here, we invoke the co-evolution of species trait-values when allocating resources to interactions to explain the structural pattern of nestedness in a mutualistic community. We look at a bipartite, multi-species system, in which the strength of an interaction between two species is determined by the resources that each species invests in that relationship. We then analyze the evolution of these interactions using adaptive dynamics. We found that the evolution of these interactions, reflecting the trade-off of resources, could be used to accurately predict that nestedness occurs significantly more often than expect due to chance alone in a mutualistic network. This complements previous results applying the same concept to an antagonistic network. We conclude that population dynamics and resource trade-offs could be important promoters of structural patterns in ecological networks of different types. [ABSTRACT FROM AUTHOR]

Introduction: Magnesium is an essential electrolyte in living organisms, which has to be supplied daily in a sufficient amount. Methods: The clinical importance of a magnesium overload or a magnesium intoxication is seldom. However, a magnesium deficiency is of special importance in humans, despite of a normal magnesium supplementation. The primary effect of a magnesium deficiency results in a reduction of energy production. This reduced energy production can result in a disturbed membrane function, calcium magnesium antagonism and cell dysfunction. Results: Thereby consequences may result in an organ dysfunction and an altered answer to external and internal stress. The reduced energy status is responsible for the recovery of unhealthy individuals - e.g. cardiac arrhythmias, primary hypertension, pre-eclampsia, cramps, allergic reactions-upon repletion of Mg status. Conclusions: The importance of an oral or intravenously supplementation of magnesium has often been described in a variety of diseases. In addition of special interest is the use of magnesium in critically ill patients in intensive care medicine. [ABSTRACT FROM AUTHOR]

We explore the processes that lead to undesirable individual-level outcomes in cross-border mergers and acquisitions (M&As). Based on the empirical findings from an in-depth longitudinal case study that describes the unsuccessful integrative efforts between a german multinational company and an austrian service provider, we develop a generic model that describes a holistic view of the processes and its relevant associated dynamics. these processes raise the awareness of aspects that significantly impact the integration process, but whose dynamics have not been linked. our model provides an explanation of why traditional attempts to integrate mostly meet with failure. [ABSTRACT FROM AUTHOR]

Films of various composition are synthesized by chemical vapor deposition under low pressure using the thermal decomposition of the following initial gas mixtures: ferrocene Fe(CH) and helium; ferrocene, tris(diethylamino)silane [(CH)N]SiH (TDEAS) and helium; ferrocene, 1,1,1,3,3,3-hexamethyldisilazane [(CH)Si]NH (HMDS), and helium. The chemical composition of the films obtained is analyzed by FTIR and Raman spectroscopies. The phase composition of the films is studied by grazing incidence X-ray diffraction (GIXRD). It is determined that the films grown from the gas mixtures of organiosilicon compounds (TDEAS or HMDS), ferrocene, and helium have the same chemical and phase composition (SiCNFe), while the films obtained from the mixture of ferrocene and helium have another composition (SiCFe). [ABSTRACT FROM AUTHOR]

Nipah virus (NiV) is a pathogenic paramyxovirus and zoononis with very high human fatality rates. Previous protein over-expression studies have shown that various mutations to the common N-terminal STAT1-binding motif of the NiV P, V, and W proteins affected the STAT1-binding ability of these proteins thus interfering with he JAK/STAT pathway and reducing their ability to inhibit type-I IFN signaling, but due to differing techniques it was unclear which amino acids were most important in this interaction or what impact this had on pathogenesis in vivo. We compared all previously described mutations in parallel and found the amino acid mutation Y116E demonstrated the greatest reduction in binding to STAT1 and the greatest reduction in interferon antagonism. A similar reduction in binding and activity was seen for a deletion of twenty amino acids constituting the described STAT1-binding domain. To investigate the contribution of this STAT1-binding motif in NiV-mediated disease, we produced rNiVs with complete deletion of the STAT1-binding motif or the Y116E mutation for ferret challenge studies (rNiVM-STAT1blind). Despite the reduced IFN inhibitory function, ferrets challenged with these rNiVM-STAT1blind mutants had a lethal, albeit altered, NiV-mediated disease course. These data, together with our previously published data, suggest that the major role of NiV P, V, and W in NiV-mediated disease in the ferret model are likely to be in the inhibition of viral recognition/innate immune signaling induction with a minor role for inhibition of IFN signaling. [ABSTRACT FROM AUTHOR]

Abstract: Animals make calls to give conspecifics information about themselves. Based on these calls, the receiver makes decisions that affect survival and reproduction. However, not all of the signals are reliable. Honest signals are either costly to produce or are constrained by physical or physiological factors that cannot be faked. Aggressive calls during antagonistic interactions are both costly and constrained by physiology. The female Asian particoloured bat (Vespertilio sinensis) produces aggressive displays and vocalizations when confronted by an intruder conspecific competing for roost position. We tested whether the aggressive calls of female Asian particoloured bats encode reliable information about the body size and the quality of the caller, and, subsequently, whether aggressive calls predicted a winning percentage that was calculated as the number of winning interactions divided by the total number of agonistic interactions. At the syllable level, there were significant positive relationships between the duration of various syllables and forearm length, bite force and winning percentage. In addition, frequency-related syllable parameters, such as peak frequency, minimum frequency, maximum frequency and bandwidth, were negatively correlated with immune response and winning percentage. At the call level, heavier bats that produced calls with shorter mean inter-syllable silences had higher winning percentage and healthier bats produced calls with lower maximum frequency. There was a significant positive relationship between immune response and vocal complexity, but no significant relationship was found between winning percentage and vocal complexity. These results suggested that aggressive calls in female Asian particoloured bats may be honest signals of body size and quality during the antagonistic interactions. Indeed, the reliability of acoustic communication in bats may be key to an in-depth understanding of the function and evolution of social calls in bats.Significance statement: Although aggressive encounters for finite resources occur frequently in many species of animals, fights to the death are quite rare in nature. Before any physical encounter, most animals exchange signals indicating fighting ability to help both contestants decide whether to retreat or to engage further in the conflict. Our results suggested that the acoustic parameters controlled by the body size and/or quality indices of Vespertilio sinensis females were significantly correlated with winning percentage. Thus female Asian particoloured bats may use aggressive vocalizations to transmit information about their body size and/or body quality (commonly used as a proxy for fighting ability) to their rivals. The rivals would be able to predict the outcome of an escalated conflict based on this information in order to decide whether to escalate or de-escalate the aggressive encounter, thereby reducing unnecessary costs. [ABSTRACT FROM AUTHOR]

A spatiotemporal discrete predator-prey system is investigated for understanding the pattern self-organization on the route to chaos. The discrete system is modelled by a coupled map lattice and shows advection of populations in space. Based on the conditions of stable stationary states and Hopf bifurcation, Turing pattern formation conditions are determined. As the parameter value is changed, self-organization of diverse patterns and complex phase transition among the patterns on the route to chaos are observed in simulations. Ordered patterns of stripes, bands, circles, and various disordered states are revealed. When we zoom in to observe the pattern transition in smaller and smaller parameter ranges, subtle structures for transition process are found: (1) alternation between self-organized structured patterns and disordered states emerges as the main nonlinear characteristic; (2) when the parameter value varies in the level from 10−3 to 10−4, a cyclic pattern transition process occurs repeatedly; (3) when the parameter value shifts in the level of 10−5 or below, stochastic pattern fluctuation dominates as essential regularity for pattern variations. The results obtained in this research promote comprehending pattern self-organization and pattern transition on the route to chaos in spatiotemporal predator-prey systems. [ABSTRACT FROM AUTHOR]

Brood parasitic birds lay their eggs in other birds' nests, leaving hosts to raise their offspring. To understand parasite-host coevolutionary arms races, many studies have examined host responses to experimentally introduced eggs. However, attending parents often need to be flushed from their nests to add experimental eggs. If these birds witness parasitism events, they may recognize and reject foreign eggs more readily than parents who did not. We found that, after being flushed, female blackbirds, Turdus merula, remained close to their nests. Flushed females were more likely to eject foreign eggs and did so more quickly than females that were not flushed during experimentation. In contrast, flushing did not predict responses and latency to responses to parasitism by song thrush, Turdus philomelos, which flew farther from their nests and likely did not witness experimental parasitism. When statistically considering flushing, previously published conclusions regarding both species' response to experimental parasitism did not change. Nevertheless, we recommend that researchers record and statistically control for whether hosts were flushed prior to experimental parasitism. Our results have broad implications because more vigilant and/or bolder parents can gain more information about parasitism events and therefore have better chances of successfully defending against brood parasitism. [ABSTRACT FROM AUTHOR]

Non-steroidal anti-inflammatory drugs (NSAIDs) are worldwide used drugs for analgesic, antipyretic, and anti-inflammatory therapeutics. However, NSAIDs often cause several serious liver injuries, such as drug-induced liver injury (DILI), and the molecular mechanisms of DILI have not been clearly elucidated. In this study, we developed a systems pharmacology approach to explore the mechanism-of-action of NSAIDs. We found that the Farnesoid X Receptor (FXR) antagonism of NSAIDs is a potential molecular mechanism of DILI through systematic network analysis and in vitro assays. Specially, the quantitative real-time PCR assay reveals that indomethacin and ibuprofen regulate FXR downstream target gene expression in HepG2 cells. Furthermore, the western blot shows that FXR antagonism by indomethacin induces the phosphorylation of STAT3 (signal transducer and activator of transcription 3), promotes the activation of caspase9, and finally causes DILI. In summary, our systems pharmacology approach provided novel insights into molecular mechanisms of DILI for NSAIDs, which may propel the ways toward the design of novel anti-inflammatory pharmacotherapeutics. [ABSTRACT FROM AUTHOR]