Unanticipated regulatory roles for Arabidopsis phytochromes revealed by null mutant analysis

In view of the extensive literature on phytochrome mutants in the Ler accession of Arabidopsis, we sought to secure a phytochrome-null line in the same genetic background for comparative studies. Here we report the isolation and phenotypic characterization of phyABCDE quintuple and phyABDE quadruple mutants in the Ler background. Unlike earlier studies, these lines possess a functional allele of FT permitting measurements of photoperiod-dependent flowering behavior. Comparative studies of both classes of mutants establish that phytochromes are dispensable for completion of the Arabidopsis life cycle under red light, despite the lack of a transcriptomic response, and also indicate that phyC is nonfunctional in the absence of other phytochromes. Phytochrome-less plants can produce chlorophyll for photosynthesis under continuous red light, yet require elevated fluence rates for survival. Unexpectedly, our analyses reveal both light-dependent and -independent roles for phytochromes to regulate the Arabidopsis circadian clock. The rapid transition of these mutants from vegetative to reproductive growth, as well as their insensitivity to photoperiod, establish a dual role for phytochromes to arrest and to promote progression of plant development in response to the prevailing light environment

Evaluation of the immunomodulatory effects of 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate in C57BL/6 mice.

2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate was designed to replace perfluorooctanoic acid (PFOA), which has been mostly phased out of U.S. production due to environmental persistence, detectable human and wildlife serum concentrations, and reports of systemic toxicity. In rodent models, PFOA exposure suppresses T cell-dependent antibody responses (TDAR) and vaccine responses in exposed humans. To determine replacement compound effects on TDAR and related parameters, male and female C57BL/6 mice were gavaged with 0, 1, 10, or 100 mg/kg/day for 28 days. Mice immunized with antigen on day 24 were evaluated for TDAR and splenic lymphocyte subpopulations five days later. Serum and urine were collected for test compound concentrations and liver peroxisome proliferation was measured. Relative liver weight at 10 and 100 mg/kg and peroxisome proliferation at 100 mg/kg were increased in both sexes. TDAR was suppressed in females at 100 mg/kg. T lymphocyte numbers were increased in males at 100 mg/kg; B lymphocyte numbers were unchanged in both sexes. Females had less serum accumulation and higher clearance than males, and males had higher urine concentrations than females at all times and doses. While this PFOA-replacement compound appears less potent at suppressing TDAR relative to PFOA, it produces detectable changes in parameters affected by PFOA; further studies are necessary to determine its full immunomodulatory profile and potential synergism with other per- and polyfluoroalkyl substances of environmental concern

Quality of medication use in primary care - mapping the problem, working to a solution: a systematic review of the literature

Background: The UK, USA and the World Health Organization have identified improved patient safety in healthcare as a priority. Medication error has been identified as one of the most frequent forms of medical error and is associated with significant medical harm. Errors are the result of the systems that produce them. In industrial settings, a range of systematic techniques have been designed to reduce error and waste. The first stage of these processes is to map out the whole system and its reliability at each stage. However, to date, studies of medication error and solutions have concentrated on individual parts of the whole system. In this paper we wished to conduct a systematic review of the literature, in order to map out the medication system with its associated errors and failures in quality, to assess the strength of the evidence and to use approaches from quality management to identify ways in which the system could be made safer. Methods: We mapped out the medicines management system in primary care in the UK. We conducted a systematic literature review in order to refine our map of the system and to establish the quality of the research and reliability of the system. Results: The map demonstrated that the proportion of errors in the management system for medicines in primary care is very high. Several stages of the process had error rates of 50% or more: repeat prescribing reviews, interface prescribing and communication and patient adherence. When including the efficacy of the medicine in the system, the available evidence suggested that only between 4% and 21% of patients achieved the optimum benefit from their medication. Whilst there were some limitations in the evidence base, including the error rate measurement and the sampling strategies employed, there was sufficient information to indicate the ways in which the system could be improved, using management approaches. The first step to improving the overall quality would be routine monitoring of adherence, clinical effectiveness and hospital admissions. Conclusion: By adopting the whole system approach from a management perspective we have found where failures in quality occur in medication use in primary care in the UK, and where weaknesses occur in the associated evidence base. Quality management approaches have allowed us to develop a coherent change and research agenda in order to tackle these, so far, fairly intractable problems

Strain-Driven Mn-Reorganization in Overlithiated LixMn2O4 Epitaxial Thin-Film Electrodes

Lithium manganate LixMn2O4 (LMO) is a lithium ion cathode that suffers from the widely observed but poorly understood phenomenon of capacity loss due to Mn dissolution during electrochemical cycling. Here, operando X-ray reflectivity (low- and high-angle) is used to study the structure and morphology of epitaxial LMO (111) thin film cathodes undergoing lithium insertion and extraction to understand the inter-relationships between biaxial strain and Mn-dissolution. The initially strain-relieved LiMn2O4 films generate in-plane tensile and compressive strains for delithiated (x 1) charge states, respectively. The results reveal reversible Li insertion into LMO with no measurable Mn-loss for 0 1) reveals Mn loss from LMO along with dramatic changes in the intensity of the (111) Bragg peak that cannot be explained by Li stoichiometry. These results reveal a partially reversible site reorganization of Mn ions within the LMO film that is not seen in bulk reactions and indicates a transition in Mn-layer stoichiometry from 3:1 to 2:2 in alternating cation planes. Density functional theory calculations confirm that compressive strains (at x = 2) stabilize LMO structures with 2:2 Mn site distributions, therefore providing new insights into the role of lattice strain in the stability of LMO

Mosquito Abundance, Bed net Coverage and Other Factors Associated with Variations in Sporozoite Infectivity Rates in Four Villages of Rural Tanzania.

Entomological surveys are of great importance in decision-making processes regarding malaria control strategies because they help to identify associations between vector abundance both species-specific ecology and disease intervention factors associated with malaria transmission. Sporozoite infectivity rates, mosquito host blood meal source, bed net coverage and mosquito abundance were assessed in this study. A longitudinal survey was conducted in four villages in two regions of Tanzania. Malaria vectors were sampled using the CDC light trap and pyrethrum spray catch methods. In each village, ten paired houses were selected for mosquitoes sampling. Sampling was done in fortnight case and study was undertaken for six months in both Kilimanjaro (Northern Tanzania) and Dodoma (Central Tanzania) regions. A total of 6,883 mosquitoes were collected including: 5,628 (81.8%) Anopheles arabiensis, 1,100 (15.9%) Culex quinquefasciatus, 89 (1.4%) Anopheles funestus, and 66 (0.9%) Anopheles gambiae s.s. Of the total mosquitoes collected 3,861 were captured by CDC light trap and 3,022 by the pyrethrum spray catch method. The overall light trap: spray catch ratio was 1.3:1. Mosquito densities per room were 96.5 and 75.5 for light trap and pyrethrum spray catch respectively. Mosquito infectivity rates between villages that have high proportion of bed net owners and those without bed nets was significant (P < 0.001) and there was a significant difference in sporozoite rates between households with and without bed nets in these four villages (P < 0.001). Malaria remains a major problem in the study areas characterized as low transmission sites. Further studies are required to establish the annual entomological inoculation rates and to observe the annual parasitaemia dynamics in these communities. Outdoor mosquitoes collection should also be considered

Spatial ecology of jaguars, pumas, and ocelots: a review of the state of knowledge

Knowledge of the spatial ecology of mammalian carnivores is critical for understanding species’ biology and designing effective conservation and management interventions. We reviewed the available information about the spatial ecology of jaguars Panthera onca, pumas Puma concolor, and ocelots Leopardus pardalis, and we examined how sex and extrinsic variables affect their spatial behaviour. Sixty-one articles addressing home range, home range overlap, daily net displacement (straight-line distance between two locations on consecutive days), and/or distance of dispersal of the three species were included. Meta-analysis, ANOVA, ANCOVA, and beta regression tests were run to analyse differences among species and sexes and to elucidate the influence of other variables, such as latitude and ecoregion, on spatial behaviour. Pumas had on average larger home ranges (mean ± SE: 281.87 ± 35.76 km) than jaguars (128.61 ± 49.5 km) and ocelots (12.46 ± 3.39 km). Intersexual range overlap was higher than intrasexual range overlap in jaguars and pumas. Sex affected the home range size of all three species, but only influenced daily net displacement in ocelots. Ecoregion affected the home range size of all three species but did not significantly affect either the daily net displacement or the dispersal distance of pumas. Latitude affected the home range size of jaguars and pumas. It did not affect daily net displacement or dispersal distance in jaguars and pumas, but did affect daily net displacement in ocelots. Although there was a lack of studies in most countries for the three species, information was particularly lacking in the Neotropics for jaguars and pumas and in North America for ocelots. Researchers usually presented low sample sizes and used different methods to examine the ecological issues considered here. Homogenisation of methods is needed to clarify the ecology of these species and to allow a better understanding of the threats to their populations.Peer Reviewe

The HY5-PIF regulatory module coordinates light and temperature control of photosynthetic gene transcription

The ability to interpret daily and seasonal alterations in light and temperature signals is essential for plant survival. This is particularly important during seedling establishment when the phytochrome photoreceptors activate photosynthetic pigment production for photoautotrophic growth. Phytochromes accomplish this partly through the suppression of phytochrome interacting factors (PIFs), negative regulators of chlorophyll and carotenoid biosynthesis. While the bZIP transcription factor long hypocotyl 5 (HY5), a potent PIF antagonist, promotes photosynthetic pigment accumulation in response to light. Here we demonstrate that by directly targeting a common promoter cis-element (G-box), HY5 and PIFs form a dynamic activation-suppression transcriptional module responsive to light and temperature cues. This antagonistic regulatory module provides a simple, direct mechanism through which environmental change can redirect transcriptional control of genes required for photosynthesis and photoprotection. In the regulation of photopigment biosynthesis genes, HY5 and PIFs do not operate alone, but with the circadian clock. However, sudden changes in light or temperature conditions can trigger changes in HY5 and PIFs abundance that adjust the expression of common target genes to optimise photosynthetic performance and growth

Higher media multi-tasking activity is associated with smaller gray-matter density in the anterior cingulate cortex

Media multitasking, or the concurrent consumption of multiple media forms, is increasingly prevalent in today’s society and has been associated with negative psychosocial and cognitive impacts. Individuals who engage in heavier media-multitasking are found to perform worse on cognitive control tasks and exhibit more socio-emotional difficulties. However, the neural processes associated with media multi-tasking remain unexplored. The present study investigated relationships between media multitasking activity and brain structure. Research has demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. Thus, we expected differential engagements in media multitasking to correlate with brain structure variability. This was confirmed via Voxel-Based Morphometry (VBM) analyses: Individuals with higher Media Multitasking Index (MMI) scores had smaller gray matter density in the anterior cingulate cortex (ACC). Functional connectivity between this ACC region and the precuneus was negatively associated with MMI. Our findings suggest a possible structural correlate for the observed decreased cognitive control performance and socio-emotional regulation in heavy media-multitaskers. While the cross-sectional nature of our study does not allow us to specify the direction of causality, our results brought to light novel associations between individual media multitasking behaviors and ACC structure differences

Linking habitat quality with genetic diversity: a lesson from great bustards in Spain

P. 411-419The effects of habitat loss and fragmentation on the genetic structure and variability of wild populations have received wide empirical support and theoretical formalization. By contrast, the effects of habitat quality seem largely underinvestigated, partly due to technical difficulties in properly assessing habitat quality. In this study, we combine geographic information system (GIS)-based habitat-quality modelling with a landscape genetics approach based on mitochondrial DNA markers to evaluate the possible influence of habitat quality on the levels and distribution of genetic diversity in a range of natural populations (n = 15) of Otis tarda throughout Spain. Ninety-three percent of the population represented by our countrywide sample lives in good-quality habitats, while 4.5% and 2.5% occur respectively in intermediate and poor habitats. Habitat quality was highly correlated with patch size, population size and population density, indicating the reliability and predictive power of the habitat suitability model. Genetic diversity was significantly correlated with habitat quality, size and density of the population, but not with patch size. Three of a total of 20 existing matrilineages from the species’ current genetic pool are restricted to poor-quality habitats. This study therefore highlights the importance of considering both population genetics and habitat quality in a species of high conservation priority.S

Robot life: simulation and participation in the study of evolution and social behavior.

This paper explores the case of using robots to simulate evolution, in particular the case of Hamilton's Law. The uses of robots raises several questions that this paper seeks to address. The first concerns the role of the robots in biological research: do they simulate something (life, evolution, sociality) or do they participate in something? The second question concerns the physicality of the robots: what difference does embodiment make to the role of the robot in these experiments. Thirdly, how do life, embodiment and social behavior relate in contemporary biology and why is it possible for robots to illuminate this relation? These questions are provoked by a strange similarity that has not been noted before: between the problem of simulation in philosophy of science, and Deleuze's reading of Plato on the relationship of ideas, copies and simulacra