9,968 research outputs found
Role of gut microbiota-generated short chain fatty acids in metabolic and cardiovascular health
Purpose of this Review:
This review assesses the latest evidence linking short-chain fatty acids (SCFA) with host metabolic health and cardiovascular disease (CVD) risk and presents the latest evidence on possible biological mechanisms.
Recent Findings:
SCFA have a range of effects locally in the gut and at both splanchnic and peripheral tissues which together appear to induce improved metabolic regulation and have direct and indirect effects on markers of CVD risk.
Summary:
SCFA produced primarily from the microbial fermentation of dietary fibre appear to be key mediators of the beneficial effects elicited by the gut microbiome. Not only does dietary fibre fermentation regulate microbial activity in the gut, SCFA also directly modulate host health through a range of tissue-specific mechanisms related to gut barrier function, glucose homeostasis, immunomodulation, appetite regulation and obesity. With the increasing burden of obesity worldwide, the role for gut microbiota-generated SCFA in protecting against the effects of energy dense diets offers an intriguing new avenue for regulating metabolic health and CVD risk
Critical behavior in an evolutionary Ultimatum Game
Experimental studies have shown the ubiquity of altruistic behavior in human
societies. The social structure is a fundamental ingredient to understand the
degree of altruism displayed by the members of a society, in contrast to
individual-based features, like for example age or gender, which have been
shown not to be relevant to determine the level of altruistic behavior. We
explore an evolutionary model aiming to delve how altruistic behavior is
affected by social structure. We investigate the dynamics of interacting
individuals playing the Ultimatum Game with their neighbors given by a social
network of interaction. We show that a population self-organizes in a critical
state where the degree of altruism depends on the topology characterizing the
social structure. In general, individuals offering large shares but in turn
accepting large shares, are removed from the population. In heterogeneous
social networks, individuals offering intermediate shares are strongly selected
in contrast to random homogeneous networks where a broad range of offers, below
a critical one, is similarly present in the population.Comment: 13 pages, 7 figure
An investigation of herpes simplex virus promoter activity compatible with latency establishment reveals VP16-independent activation of immediate-early promoters in sensory neurones
Herpes simplex virus (HSV) type-1 establishes lifelong latency in sensory neurones and it is widely assumed that latency is the consequence of a failure to initiate virus immediate-early (IE) gene expression. However, using a Ore reporter mouse system in conjunction with Ore-expressing HSV-1 recombinants we have previously shown that activation of the IE ICPO promoter can precede latency establishment in at least 30 % of latently infected cells. During productive infection of non-neuronal cells, IE promoter activation is largely dependent on the transactivator VP16 a late structural component of the virion. Of significance, VP16 has recently been shown to exhibit altered regulation in neurones; where its de novo synthesis is necessary for IE gene expression during both lytic infection and reactivation from latency. In the current study, we utilized the Ore reporter mouse model system to characterize the full extent of viral promoter activity compatible with cell survival and latency establishment. In contrast to the high frequency activation of representative IE promoters prior to latency establishment, cell marking using a virus recombinant expressing Ore under VP16 promoter control was very inefficient. Furthermore, infection of neuronal cultures with VP16 mutants reveals a strong VP16 requirement for IE promoter activity in non-neuronal cells, but not sensory neurones. We conclude that only IE promoter activation can efficiently precede latency establishment and that this activation is likely to occur through a VP16-independent mechanism
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A Tale of two Cities: A study of access and attitudes to food in the Deepdale and Ingol areas of Preston
Designing a road traffic model for the cross-sectoral analysis of future national infrastructure
This paper presents a UK national road traffic model developed as part of the ITRC MISTRAL - a large
interdisciplinary project of the Infrastructure Transitions Research Consortium (ITRC). The proposed
model includes passenger and freight vehicle flows on major UK roads and predicts future demand in the
form of an inter-zonal origin-destination matrix, using and elasticity-based simulation approach. An
important part of the model is the network assignment step during which predicted flows are assigned to
the road network. This allows for the assessment of road capacity utilisation and facilitates the
identification of "pinch points" where future infrastructure investments might be targeted. Several policy
interventions are studied in the paper, including road expansion with additional lanes, new road
development and vehicle electrification. The model also explicitly considers cross-sectoral
interdependencies with other infrastructure networks, primarily with the energy sector where the
transport sector is the largest consumer, the digital communications sector, water supply and waste
management. In future extensions, the model will also be able to estimate the environmental footprint
and assess the risk and resilience of the transport network. This model has the potential to inform policy
makers about the long-term performance of UK road infrastructure, considering a range of possible
future scenarios for population growth, technological innovation and climate change
Geology of the Snap Lake kimberlite intrusion, Northwest Territories, Canada: field observations and their interpretation
The Cambrian (523 Ma) Snap Lake hypabyssal kimberlite intrusion, Northwest Territories, Canada, is a complex segmented diamond-bearing ore-body. Detailed geological investigations suggest that the kimberlite is a multi-phase intrusion with at least four magmatic lithofacies. In particular, olivine-rich (ORK) and olivine-poor (OPK) varieties of hypabyssal kimberlite have been identified. Key observations are that the olivine-rich lithofacieshas a strong tendency to be located where the intrusion is thickest and that there is a good correlation between intrusion thickness, olivine crystal size and crystal content. Heterogeneities in the lithofacies are attributed to variations in intrusion thickness and structural complexities. The geometry and distribution of lithofacies points to magmaticco-intrusion, and flow segregation driven by fundamental rheological differences between the two phases. We envisage that the low-viscosity OPK magma acted as a lubricant for the highly viscous ORK magma. The presenceof such low-viscosity, crystal-poor magmas may explain how crystal-laden kimberlite magmas (>60 vol.%) are able to reach the surface during kimberlite eruptions. We also document the absence of crystal settling and the development of an unusual subvertical fabric of elongate olivine crystals, which are explained by rapid degassing-induced quench crystallization of the magmas during and after intrusio
Solution of the Bohr hamiltonian for soft triaxial nuclei
The Bohr-Mottelson model is solved for a generic soft triaxial nucleus,
separating the Bohr hamiltonian exactly and using a number of different
model-potentials: a displaced harmonic oscillator in , which is solved
with an approximated algebraic technique, and Coulomb/Kratzer,
harmonic/Davidson and infinite square well potentials in , which are
solved exactly. In each case we derive analytic expressions for the
eigenenergies which are then used to calculate energy spectra.
Here we study the chain of osmium isotopes and we compare our results with
experimental information and previous calculations.Comment: 13 pages, 9 figure
Eperythrozoonosis in 4-week-old Pigs
Eperythrozoon suis is considered to be the major cause of icteroanemia in swine. Knowledge concerning the mode of transmission of eperythrozoonosis is incomplete. Because most cases of eperythrozoonosis occur during the warm months of the year, it has been assumed that dissemination of the blood parasite could be most easily accomplished by bloodsucking arthropod vectors
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