Although the recent Zika virus (ZIKV) epidemic in the Americas and its link to birth defects have attracted a great deal of attention, much remains unknown about ZIKV disease epidemiology and ZIKV ...evolution, in part owing to a lack of genomic data. Here we address this gap in knowledge by using multiple sequencing approaches to generate 110 ZIKV genomes from clinical and mosquito samples from 10 countries and territories, greatly expanding the observed viral genetic diversity from this outbreak. We analysed the timing and patterns of introductions into distinct geographic regions; our phylogenetic evidence suggests rapid expansion of the outbreak in Brazil and multiple introductions of outbreak strains into Puerto Rico, Honduras, Colombia, other Caribbean islands, and the continental United States. We find that ZIKV circulated undetected in multiple regions for many months before the first locally transmitted cases were confirmed, highlighting the importance of surveillance of viral infections. We identify mutations with possible functional implications for ZIKV biology and pathogenesis, as well as those that might be relevant to the effectiveness of diagnostic tests.
Many streams in the Mediterranean Basin have temporary flow regimes. While timing for seasonal drought is predictable, they undergo strong inter-annual variability in flow intensity. This high ...hydrological variability and associated ecological responses challenge the ecological status assessment of temporary streams, particularly when setting reference conditions. This study examined the effects of flow connectivity in aquatic macroinvertebrates from seven reference temporary streams across the Mediterranean Basin where hydrological variability and flow conditions are well studied. We tested for the effect of flow cessation on two streamflow indices and on community composition, and, by performing random forest and classification tree analyses we identified important biological predictors for classifying the aquatic state either as flowing or disconnected pools. Flow cessation was critical for one of the streamflow indices studied and for community composition. Macroinvertebrate families found to be important for classifying the aquatic state were Hydrophilidae, Simuliidae, Hydropsychidae, Planorbiidae, Heptageniidae and Gerridae. For biological traits, trait categories associated to feeding habits, food, locomotion and substrate relation were the most important and provided more accurate predictions compared to taxonomy. A combination of selected metrics and associated thresholds based on the most important biological predictors (i.e. Bio-AS Tool) were proposed in order to assess the aquatic state in reference temporary streams, especially in the absence of hydrological data. Although further development is needed, the tool can be of particular interest for monitoring, restoration, and conservation purposes, representing an important step towards an adequate management of temporary rivers not only in the Mediterranean Basin but also in other regions vulnerable to the effects of climate change.
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•The effect of flow connectivity on macroinvertebrate communities was tested on temporary rivers.•Using recursive partitioning, biological metrics were selected to classify flow connectivity.•Biological trait-based metrics represented antecedent flow conditions of a stream reach.•A Bio-AS Tool (based on both taxonomy and traits) is proposed.
A sustainable workforce is important for the veterinary profession to meet the demands of society. To maintain a sustainable workforce, it has been recommended to retain veterinary clinicians. ...However, there seems to be an increasing issue with retention of veterinarians in clinical practice. In the following study, the researchers sought to understand the associations between demographic and work‐related factors and attrition of veterinarians from clinical practice. Responses to an online cross‐sectional survey of 881 current and former Australian veterinary clinicians were analysed. A logistic regression model was used to identify and describe associations between attrition from veterinary clinical practice and salary, working hours, role in practice, years of experience, field of work, interaction with regulatory authorities, region of work and on‐call duties. Lower salary, longer working hours, having on‐call duties and having worked in both rural and metropolitan regions were found to significantly (P < 0.05) increase the likelihood of leaving clinical practice. The results may inform intervention strategies to assist the industry to retain veterinarians in clinical practice.
The European Water Framework Directive establishes the need to define stream type-specific reference conditions to identify “high ecological status”. Methods for selecting reference sites using a ...priori criteria have been proposed by many authors. A review of these criteria revealed that the most relevant criteria for streams and rivers were those related to riparian vegetation, diffuse and point sources of pollution, river morphology and hydrological conditions and regulation. In this work, we propose 20 criteria that reflect the characteristics of Mediterranean streams and their most frequent disturbances for the selection of reference sites in Mediterranean streams in Spain. We studied 162 sites located in 33 Mediterranean basins belonging to five stream types. Of the locations, 57% were selected as a priori reference sites by having applied the proposed criteria. Reference sites were identified for all stream types except for “large watercourses” which includes the lower reaches of some rivers in this study area. This a priori selection of reference sites was subjected to validation using the macroinvertebrate community by applying of an IBMWP threshold, which is considered to be an indicator of undisturbed sites in Mediterranean streams. This approach determined that whole of this selection (100%) could be considered valid reference sites. Furthermore, we identified differences in the reference conditions for each stream type on the basis of macroinvertebrate assemblage composition.
•Eustressors are physical, chemical, and biological stress factors that might improve vegetables production.•Eustressors have shown to improve plant growth, quality and alleviate stresses.•Basic ...concepts on eustressors should be clarified to apply in horticulture for legislation purposes.•Physical eustressors deserves to be considered to enhance vegetables production.•Eustressors should regularly be used in vegetables production systems.
Worldwide plants are exposed to different biotic and abiotic stress factors limiting yield, growth, quality and performance. Agricultural and horticultural practices for food production aim at plant cultivation at minimized stress using different production systems either under protected or open field conditions. However, it is also possible to stress plants to enhance horticultural production. The theory of stress indicates a dose/response relationship between the strength and length of the stress factor (stressor) and the plant response. Plant responses to cope stress are triggered after recognition of a range of biological, chemical, and physical stressors. Slight doses of stressors might cause positive effects on plant performance (“positive stress” or eustress), whereas on the contrary, high doses provoke negative effects (“negative stress” or distress). Managed as eustress dose and lenght, an eustressor might stimulates the plant response in such a way that plant production and quality are improved. A myriad of literature has reported beneficial effects for the applications of biological (biostimulants/elicitors) and non-biological chemical eustressors in horticulture. However, physical eustressors have not been exhaustively studied in this sense. The present review aims at presenting the current status of the concepts, case studies and applications of eustressors in horticulture. Moreover, the review focuses on the necessity of exploring physical eustressors as stress factors that modulate and increase the quality of horticultural commodities.
Biodiversity increases the ability of ecosystems to provide multiple functions. Most studies report a positive relationship between species richness and the number of ecosystem functions. However, it ...is not known whether the number of functional groups is related to the structure of the underlying species interaction network. Here we present food web data from 115 salt marsh islands and show that network structure is associated with the number of functional groups present. Functional group diversity is heterogeneously distributed across spatial scales, with some islands hosting more functional groups than others. Functional groups form modules within the community so that food webs with more modular architectures have more functional group diversity. Further, in communities with different interaction types, modularity can be seen as the multifunctional equivalent of trophic complementarity. Collectively, these findings reveal spatial heterogeneity in the number of functional groups that emerges from patterns in the structure of the food web.
Ion channel conformational changes within the lipid membrane are a key requirement to control ion passage. Thus, it seems reasonable to assume that lipid composition should modulate ion channel ...function. There is increasing evidence that this implicates not just an indirect consequence of the lipid influence on the physical properties of the membrane, but also specific binding of selected lipids to certain protein domains. The result is that channel function and its consequences on excitability, contractility, intracellular signaling or any other process mediated by such channel proteins, could be subjected to modulation by membrane lipids. From this it follows that development, age, diet or diseases that alter lipid composition should also have an influence on those cellular properties. The wealth of data on the non-annular lipid binding sites in potassium channel from Streptomyces lividans (KcsA) makes this protein a good model to study the modulation of ion channel structure and function by lipids. The fact that this protein is able to assemble into clusters through the same non-annular sites, resulting in large changes in channel activity, makes these sites even more interesting as a potential target to develop lead compounds able to disrupt such interactions and hopefully, to modulate ion channel function. This Article is Part of a Special Issue Entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
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•Specific lipids bound to ion channels modulate their structure and function.•Non-annular lipid binding sites on KcsA mediate interactions leading to protein clustering.•Lipid–protein and protein–protein interactions strongly modulate KcsA function.
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