Dietary influences over proliferating cell nuclear antigen expression in the locust midgut

We have studied the influence of variations in dietary protein (P) and digestible carbohydrate (C), the quantity of food eaten, and insect age during the fifth instar on the expression of the proliferating cell nuclear antigen (PCNA) in the epithelial cells of the midgut (with special reference to the midgut caeca) in the African migratory locust, Locusta migratoria. Densitometric analysis of PCNA-immunostained cells was used as an indirect measure of the levels of expression of PCNA, and a PCNA cellular index (PCNA-I) was obtained. Measurements of the DNA content of the cells have also been carried out by means of microdensitometry of Feulgen-stained, thick sections of midgut. A comparison between the PCNA nuclear level and the DNA content was performed. The PCNA levels were significantly different among the cells of the five regions studied: caeca, anterior ventricle, medial ventricle, posterior ventricle and ampullae of the Malpighian tubules. We have studied in more detail the region with highest PCNA-I, i.e. the caeca. The quality and the quantity of food eaten under ad libitum conditions were highly correlated with both the PCNA and DNA levels in the caeca cells. Locusts fed a diet with a close to optimal P:C content (P 21%, C 21%) showed the highest PCNA and DNA content. In locusts fed a food that also contained a 1:1 ratio of P to C but was diluted three-fold by addition of indigestible cellulose (P 7%, C 7%), a compensatory increase in consumption was critical to maintaining PCNA levels. Our measurements also showed that the nuclear DNA content of the mature and differentiated epithelial cells was several-fold higher than the levels in the undifferentiated stem cells of the regenerative nests. These results, combined with the low number of mitotic figures found in the regenerative nests of the caeca and the marked variation in PCNA levels among groups, suggest that some type of DNA endoreduplication process may be taking place. Our data also indicate that the DNA synthetic activity in the midgut is related to feeding in locusts. The possible dietary and nutritional regulatory mechanisms and the significance of the differences found are discussed

Effects of food nutrient content, insect age and stage in the feeding cycle on the FMRFamide immunoreactivity of diffuse endocrine cells in the locust gut

We have studied the influence of variations in dietary protein and digestible carbohydrate content, of insect age and of time during the feeding cycle on the endocrine cells of the ampullar region of the midgut in the African migratory locust Locusta migratoria L. Morphometric analysis of FMRFamide-like immunoreactivity was used as an indirect measure of the amount of FMRFamide-related peptides (FaRPs) stored in the gut endocrine cells. There was a highly significant correlation between FaRP content and the nutritional quality of the food, measured relative to the concentrations and ratio of protein to digestible carbohydrate in a nutritionally optimal diet. The direction of the relationship between FaRP content and diet quality varied with age during the fifth stadium. On day 1, FaRP levels increased with the nutritional quality of the food, while on day 4 the opposite relationship was observed. Release of peptide was triggered by the onset of a meal during ad libitum feeding, with cell FaRP levels returning to premeal values within 15 min of the meal ending. The results also suggested that cell contents were released during food deprivation beyond the normal intermeal interval. Locusts switched for a single meal during ad libitum feeding on day 4 from a low- to a high-carbohydrate food did not respond by reducing endocrine cell FaRP content. Our results show a relationship between the diffuse gut endocrine system and feeding and nutrition in locusts. The ampullar endocrine cells are in three-way contact with the midgut luminal contents, with the primary urine from the Malpighian tubules and with the haemolymph. They are thus ideally positioned to play an integrative receptor-secretory function in the regulation of a variety of post-ingestive processes, such as enzyme secretion, absorption, gut motility or nutrient metabolism

Diversity and impact of rare variants in genes encoding the platelet G protein-coupled receptors

Platelet responses to activating agonists are influenced by common population variants within or near G protein-coupled receptor (GPCR) genes that affect receptor activity. However, the impact of rare GPCR gene variants is unknown. We describe the rare single nucleotide variants (SNVs) in the coding and splice regions of 18 GPCR genes in 7,595 exomes from the 1,000-genomes and Exome Sequencing Project databases and in 31 cases with inherited platelet function disorders (IPFDs). In the population databases, the GPCR gene target regions contained 740 SNVs (318 synonymous, 410 missense, 7 stop gain and 6 splice region) of which 70 % had global minor allele frequency (MAF) < 0.05 %. Functional annotation using six computational algorithms, experimental evidence and structural data identified 156/740 (21 %) SNVs as potentially damaging to GPCR function, most commonly in regions encoding the transmembrane and C-terminal intracellular receptor domains. In 31 index cases with IPFDs (Gi-pathway defect n=15; secretion defect n=11; thromboxane pathway defect n=3 and complex defect n=2) there were 256 SNVs in the target regions of 15 stimulatory platelet GPCRs (34 unique; 12 with MAF< 1 % and 22 with MAF≥ 1 %). These included rare variants predicting R122H, P258T and V207A substitutions in the P2Y12 receptor that were annotated as potentially damaging, but only partially explained the platelet function defects in each case. Our data highlight that potentially damaging variants in platelet GPCR genes have low individual frequencies, but are collectively abundant in the population. Potentially damaging variants are also present in pedigrees with IPFDs and may contribute to complex laboratory phenotypes

Convergence calls: multimedia storytelling at British news websites

This article uses qualitative interviews with senior editors and managers from a selection of the UK's national online news providers to describe and analyse their current experimentation with multimedia and video storytelling. The results show that, in a period of declining newspaper readership and TV news viewing, editors are keen to embrace new technologies, which are seen as being part of the future of news. At the same time, text is still reported to be the cornerstone for news websites, leading to changes in the grammar and function of news video when used online. The economic rationale for convergence is examined and the article investigates the partnerships sites have entered into in order to be able to serve their audience with video content. In-house video is complementing syndicated content, and the authors examine the resulting developments in newsroom training and recruitment practices. The article provides journalism and interactive media scholars with case studies on the changes taking place in newsrooms as a result of the shift towards multimedia, multiplatform news consumption

Effectiveness and cost-effectiveness of daily all-over-body application of emollient during the first year of life for preventing atopic eczema in high-risk children (The BEEP trial): protocol for a randomised controlled trial.

BACKGROUND: Atopic eczema (AE) is a common skin problem that impairs quality of life and is associated with the development of other atopic diseases including asthma, food allergy and allergic rhinitis. AE treatment is a significant cost burden for health care providers. The purpose of the trial is to investigate whether daily application of emollients for the first year of life can prevent AE developing in high-risk infants (first-degree relative with asthma, AE or allergic rhinitis). METHODS: This is a protocol for a pragmatic, two-arm, randomised controlled, multicentre trial. Up to 1400 term infants at high risk of developing AE will be recruited through the community, primary and secondary care in England. Participating families will be randomised in a 1:1 ratio to receive general infant skin-care advice, or general skin-care advice plus emollients with advice to apply daily to the infant for the first year of life. Families will not be blinded to treatment allocation. The primary outcome will be a blinded assessment of AE at 24 months of age using the UK Working Party Diagnostic Criteria for Atopic Eczema. Secondary outcomes are other definitions of AE, time to AE onset, severity of AE (EASI and POEM), presence of other allergic diseases including food allergy, asthma and hay fever, allergic sensitisation, quality of life, cost-effectiveness and safety of the emollients. Subgroup analyses are planned for the primary outcome according to filaggrin genotype and the number of first-degree relatives with AE and other atopic diseases. Families will be followed up by online and postal questionnaire at 3, 6, 12 and 18 months with a face-to-face visit at 24 months. Long-term follow-up until 60 months will be via annual questionnaires. DISCUSSION: This trial will demonstrate whether skin-barrier enhancement through daily emollient for the first year of life can prevent AE from developing in high-risk infants. If effective, this simple and cheap intervention has the potential to result in significant cost savings for health care providers throughout the world by preventing AE and possibly other associated allergic diseases. TRIAL REGISTRATION: ISRCTN registry; ID: ISRCTN21528841 . Registered on 25 July 2014

Domain Wall Spacetimes: Instability of Cosmological Event and Cauchy Horizons

The stability of cosmological event and Cauchy horizons of spacetimes associated with plane symmetric domain walls are studied. It is found that both horizons are not stable against perturbations of null fluids and massless scalar fields; they are turned into curvature singularities. These singularities are light-like and strong in the sense that both the tidal forces and distortions acting on test particles become unbounded when theses singularities are approached.Comment: Latex, 3 figures not included in the text but available upon reques

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.Comment: 161 pages, Review, Eur Phys J Special-Topics, accepte

Junior staffing changes and the temporal ecology of adverse incidents in acute psychiatric wards

Aim.  This paper reports an examination of the relationship between adverse incident rates, the arrival of new junior staff on wards, and days of the week on acute psychiatric wards. Background.  Incidents of violence, absconding and self-harm in acute inpatient services pose risks to patients and staff. Previous research suggests that the arrival of inexperienced new staff may trigger more adverse incidents. Findings on the relationship between incidents and the weekly routine are inconsistent. Method.  A retrospective analysis was conducted of formally reported incident rates, records of nursing student allocations and junior doctor rotation patterns, using Poisson Regression. Variance between days of the week was explored using contingency table analysis. The data covered 30 months on 17 psychiatric wards, and were collected in 2002–2004. Findings.  The arrival of new and inexperienced staff on the wards was not associated with increases in adverse incident rates. Most types of incidents were less frequent at weekends and midweek. Incident rates were unchanged on ward-round days, but increased rates were found on the days before and after ward rounds. Conclusion.  Increased patient tension is associated with raised incident rates. It may be possible to reduce incident rates by moderating stimulation in the environment and by mobilizing support for patients during critical periods

Broad Down, Devon: archaeological and other stories

publication-status: PublishedThis is a post-print, author-produced version of an article accepted for publication Journal of Material Culture, 2010, Vol. 15, Issue 3, pp. 345 - 367. Copyright © 2010 SAGE Publications. The definitive publisher-authenticated version is available online at http://mcu.sagepub.com/content/15/3/345.shortThis article explores the knowledge construction process of an archaeological site in East Devon, UK. Bouncing off an oral historical account of the site that seems to run against scientific truth claims, the author investigates the story of how knowledge of the site has developed over the last two centuries. Building on previous work that explores the history and practice of archaeology, the article opens up questions of what counts as evidence. Then, taking a cue from more recent work that suggests a more dynamic and open-ended engagement with the landscape, the article turns to examine how the meaning of a site can be made and remade. As part of this endeavour, questions of what as well as who can ‘speak’ are examined and some space is opened up for the agency of ‘minor figures’, both human and non-human

Adaptive plant traits under anthropogenic burning regimes: a database for UK heath and mire plant species

Premise Humans have used fire to manage landscapes for millennia, but this use of fire is declining in many ecosystems. Understanding how plants respond to these changes is key to predicting ecosystem resilience and impacts on services such as biodiversity and carbon sequestration. However, many ecosystems lack data on plant fire responses. A solution is to infer these responses through studying functional traits that offer fitness benefits under fire by enabling species to resist fire, or persist through fire, by resprouting or recruitment from stored seed banks or dispersed seed. Studying these traits helps predict species performance under fire. Methods We used a trait-based approach to create a database of fire-relevant traits and fire responses for vascular and nonvascular plant species in UK heath and mire ecosystems managed by fire. By reviewing the available literature, we collected data on traits adaptive under frequent burns for 153 plant taxa that could then be used to make predictions about fire effects. Results Of the 153 taxa assessed, 97% had fire-adaptive traits; 149 taxa had resistance and/or persistence traits, enabling survival or regeneration after fire. Additionally, 20 taxa showed fire-enhanced recruitment, while only four lacked traits aiding survival during or after fire. Conclusions The database created here is designed to be a resource for those who study and manage heath and mire ecosystems. The use of fire in areas where heath is underlain by peat is much debated, and this database can inform how changing or removing the use of fire will impact plant communities