Unexpected spatial stability of water chemistry in headwater stream networks

Understanding how water and solutes enter and propagate through freshwater landscapes in the Anthropocene is critical to protecting and restoring aquatic ecosystems and ensuring human water security. However, high hydrochemical variability in headwater streams, where most carbon and nutrients enter river networks, has hindered effective modelling and management. We developed an analytical framework informed by landscape ecology and catchment hydrology to quantify spatiotemporal variability across scales, which we tested in 56 headwater catchments, sampled periodically over 12 years in western France. Unexpectedly, temporal variability in dissolved carbon, nutrients and major ions was preserved moving downstream and spatial patterns of water chemistry were stable on annual to decadal timescales, partly because of synchronous variation in solute concentrations. These findings suggest that while concentration and flux cannot be extrapolated among subcatchments, periodic sampling of headwaters provides valuable information about solute sources and subcatchment resilience to disturbance.     

Node self‐connections and metapopulation persistence: reply to Saura (2018)

Saura ( 2018 ) claims that studies using the Probability of Connectivity metric (PC) had already demonstrated the importance of including node self‐connections in network metrics. As originally defined and used, PC cannot test the importance of self‐connections. However, with key terms redefined, PC could be a useful tool in future work.     

A graph-based approach to defend agro-ecological systems against water vole outbreaks

The cyclic spread of montane water vole populations in the grasslands of the Jura plateaus causes severe economic, ecological, and public-health problems. Since this phenomenon cannot be managed by massive use of the anticoagulant rodenticide bromadiolone, the challenge is to limit it by reducing regional-level connectivity through landscaping and agro-environmental interventions such as planting hedgerows, ploughing, and cultivating cereals. We used landscape graphs – a spatial modelling approach based on graph theory – to represent the grassland network and identify key areas for intervention. Several strategies were compared in terms of their capacity to fulfil operational requirements by interchanging patches and meta-patches as nodes of the graph, and least-cost distances and resistance distances to weight links. The combination of meta-patches and resistance distances provides a relevant basis on which to design concrete action to decrease regional-level connectivity of grasslands. The results also indicate that the usual removal method applied to the links of the graph would benefit from data on the statistical distribution of cost values along the shortest paths. More broadly, this suggests the modelling approach should be better matched the actual field interventions if the connectivity analysis is to be operational.     

Green pathways: Metabolic network analysis of plant systems

Metabolic engineering of plants with enhanced crop yield and value-added compositional traits is particularly challenging as they probably exhibit the highest metabolic network complexity of all living organisms. Therefore, approaches of plant metabolic network analysis, which can provide systems-level understanding of plant physiology, appear valuable as guidance for plant metabolic engineers. Strongly supported by the sequencing of plant genomes, a number of different experimental and computational methods have emerged in recent years to study plant systems at various levels: from heterotrophic cell cultures to autotrophic entire plants. The present review presents a state-of-the-art toolbox for plant metabolic network analysis. Among the described approaches are different in silico modeling techniques, including flux balance analysis, elementary flux mode analysis and kinetic flux profiling, as well as different variants of experiments with plant systems which use radioactive and stable isotopes to determine in vivo plant metabolic fluxes. The fundamental principles of these techniques, the required data input and the obtained flux information are enriched by technical advices, specific to plants. In addition, pioneering and high-impacting findings of plant metabolic network analysis highlight the potential of the field.     

The impact of a knowledge translation intervention employing educational outreach and a point-of-care reminder tool vs standard lay health worker training on tuberculosis treatment completion rates: study protocol for a cluster randomized controlled trial

BackgroundDespite availability of effective treatment, tuberculosis (TB) remains an important cause of morbidity and mortality globally, with low- and middle-income countries most affected. In many such settings, including Malawi, the high burden of disease and severe shortage of skilled healthcare workers has led to task-shifting of outpatient TB care to lay health workers (LHWs). LHWs improve access to healthcare and some outcomes, including TB completion rates, but lack of training and supervision limit their impact. The goals of this study are to improve TB care provided by LHWs in Malawi by refining, implementing, and evaluating a knowledge translation strategy designed to address a recognized gap in LHWs’ TB and job-specific knowledge and, through this, to improve patient outcomes.Methods/designWe are employing a mixed-methods design that includes a pragmatic cluster randomized controlled trial and a process evaluation using qualitative methods. Trial participants will include all health centers providing TB care in four districts in the South East Zone of Malawi. The intervention employs educational outreach, a point-of-care reminder tool, and a peer support network. The primary outcome is proportion of treatment successes, defined as the total of TB patients cured or completing treatment, with outcomes taken from Ministry of Health treatment records. With an alpha of 0.05, power of 0.80, a baseline treatment success of 0.80, intraclass correlation coefficient of 0.1 based on our pilot study, and an estimated 100 clusters (health centers providing TB care), a minimum of 6 patients per cluster is required to detect a clinically significant 0.10 increase in the proportion of treatment successes. Our process evaluation will include interviews with LHWs and patients, and a document analysis of LHW training logs, quarterly peer trainer meetings, and mentorship meeting notes. An estimated 10–15 LHWs and 10–15 patients will be required to reach saturation in each of 2 planned interview periods, for a total of 40–60 interview participants.DiscussionThis study will directly inform the efforts of knowledge users within TB care and, through extension of the approach, other areas of care provided by LHWs in Malawi and other low- and middle-income countries.

Trial registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT02533089","term_id":"NCT02533089"}}NCT02533089. Registered 20 August 2015. Protocol Date/Version 29 May 2016/Version 2.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1563-2) contains supplementary material, which is available to authorized users.     

General stress proteins in Bacillus subtilis

Abstract Bacillus cells frequently faced with various adverse environmental factors in nature have evolved different adaptational strategies. The induction of stress proteins is an essential component of this adaptational network. In Bacillus subtilis there are two groups of stress proteins. The first group is factor specific, whereas the second group is induced by growth restrictive conditions in general. The relationship between the stringent response and the induction of stress proteins is discussed.     

Periclinal penetration of potassium permanganate into mature cuticular membranes ofAgave andClivia leaves: new implications for plant cuticle development

Staining cuticular membranes ofAgave americana andClivia miniata en bloc with potassium permanganate results in a strong contrast in the interior cuticular layer while the exterior part remains unstained. This is not caused by a selective chemical reaction with the interior part but by the unidirectional penetration of the reagent from the interior side, the outside being protected by the cuticle proper. In transverse cryosections of the cuticular membrane, permanganate penetrates nearly as easily into the exterior cuticular layer as into the interior one giving the same contrast. However, compared with the periclinal penetration into the cuticle proper this penetration is accelerated five-to tenfold by the polysaccharide network within the cuticular layer which serves as a distribution-channel system. Periclinal penetration into the cuticle proper occurs independently in each cutin penetration unit included between two obvious lucent lamellae and further divided into subunits.     

Anti-colorectal cancer targets of resveratrol and biological molecular mechanism: Analyses of network pharmacology,human and experimental data

In this study, colorectal cancer (CRC)-diseased targets and resveratrol (Res)-associated targets were combined and constructed by the use of grouped databases for identification of the predicted targets. After production of target-functional protein interaction network of Res anti-CRC, the topological analysis was used to create the core targets of Res anti-CRC. All core targets performed the analyses of biological function and pathway enrichment to optimize the biological processes and key signaling pathways of Res anti-CRC. The resultant five core therapeutic targets of Res anti-CRC were identified as protein kinase B1 (AKT1), interleukin 6 (IL6), Tumor protein p53 (TP53), vascular endothelial growth factor, and mitogen-activated protein kinase 1, respectively. Biological processes of Res anti-CRC were predominantly associated with regulating apoptosis, immune response, cellular communication, signal transduction, and metabolism of the nuclide. In addition, the top 10 key signaling pathways were identified, respectively. In human CRC sample assays, CRC histologic sections showed elevated expression of AKT1 and IL6 proteins, accompanied with abnormal changes in blood molecules. In pharmacological experiments of Res anti-CRC in vitro, Res-treated HCT116 cells showed inhibited cell growth, induced cell death. In addition, downregulation of intracellular AKT1 and IL6 expression were checked in Res-treated HCT116 cells. Taken together, these bioinformatic findings and preliminary validated data uncovered pharmacological molecular mechanisms associated with Res anti-CRC, and further identified top five core therapeutic targets. Beneficially, these five predicted targets might serve as potential biomolecules for anti-CRC treatment.