1,967 research outputs found
Developing an index of vulnerability to motor fuel price increases in England
As the outlook for oil prices remains uncertain, this paper develops a method to assess which areas of England would be most vulnerable to future motor fuel price increases. Building on previous research, we define and operationalise three dimensions of vulnerability: exposure (the cost burden of motor fuel), sensitivity (income) and adaptive capacity (accessibility with modes alternative to the car). We exploit unique data sets available in England, including the ‘MOT’ vehicle inspection data and DfT Accessibility Statistics. This allows us to map vulnerability to fuel price increases at a spatially disaggregated level (Lower-layer Super Output Areas), taking into account motor-fuel expenditure for all travel purposes, and the ability of households to shift to other modes of travel. This is an advancement on the ‘oil vulnerability’ indices developed in previous international research
Tannins-Based Extracts: Effects on Gut Chicken Spontaneous Contractility
The impossibility of using drugs for the health of farm animals leads to the search for alternative strategies with two purposes: to maintain animal health and safeguard human health. In this perspective, tannins have shown great promises. These phytocomplexes obtained from natural matrices with multiple health properties may be used as a feed supplement in chicken farms. In this work, we studied two tannin-based extracts (from Castanea sativa Mill. wood and from Schinopsis balansae Engl. Quebracho Colorado hardwood) with different chemical compositions on the spontaneous contractility on the isolated intestinal tissues of healthy chicken. The results showed that the chemical composition of the two phytocomplexes influenced the spontaneous intestinal contractility in different ways by regulating the tone and consequent progression of the food bolus. The chemical analysis of the two extracts revealed that Castanea sativa Mill. wood mainly contains hydrolysable tannins, while Schinopsis balansae Engl. hardwood mainly contains condensed tannins. The two phytocomplexes showed different effects towards gastrointestinal smooth muscle contractility, with Castanea sativa Mill. wood providing a better activity profile than Schinopsis balansae Engl. hardwood
Axisymmetric equilibria of a gravitating plasma with incompressible flows
It is found that the ideal magnetohydrodynamic equilibrium of an axisymmetric
gravitating magnetically confined plasma with incompressible flows is governed
by a second-order elliptic differential equation for the poloidal magnetic flux
function containing five flux functions coupled with a Poisson equation for the
gravitation potential, and an algebraic relation for the pressure. This set of
equations is amenable to analytic solutions. As an application, the
magnetic-dipole static axisymmetric equilibria with vanishing poloidal plasma
currents derived recently by Krasheninnikov, Catto, and Hazeltine [Phys. Rev.
Lett. {\bf 82}, 2689 (1999)] are extended to plasmas with finite poloidal
currents, subject to gravitating forces from a massive body (a star or black
hole) and inertial forces due to incompressible sheared flows. Explicit
solutions are obtained in two regimes: (a) in the low-energy regime
, where
, , , and are related to the thermal,
poloidal-current, flow and gravitating energies normalized to the
poloidal-magnetic-field energy, respectively, and (b) in the high-energy regime
. It turns out
that in the high-energy regime all four forces, pressure-gradient,
toroidal-magnetic-field, inertial, and gravitating contribute equally to the
formation of magnetic surfaces very extended and localized about the symmetry
plane such that the resulting equilibria resemble the accretion disks in
astrophysics.Comment: 12 pages, latex, to be published in Geophys. Astrophys. Fluid
Dynamic
Permutation centralizer algebras and multimatrix invariants
45 pages, 5 figures45 pages, 5 figure
Let's focus more on negative trends: A comment on the transitions research agenda
Much has been written on sustainability transitions, yet all around us unsustainable developments remain rife, and threaten to offset the progress made in other areas. This viewpoint argues that transitions scholarship should widen its scope to consider unsustainable trends, which it has tended to neglect to date. We argue that there is merit in applying the transitions lens to these developments, not least because of its systemic approach, which could help highlight the dynamic relationships between sustainable and unsustainable trends. We sketch some high-level questions for future transitions research including: how unsustainable trends emerge, who drives them, and how research could help to curtail harmful socio-technological changes before they become entrenched. We conclude by arguing that investigating unsustainable trends would benefit transitions research by making it more plural and more radical
SARS-CoV-2 tracheitis in laryngectomised patients: A consecutive case-series study
Key points
SARS-CoV-2 is a possible cause of acute severe tracheitis in laryngectomees.
In our series, the clinical picture was characterized by a haemorrhagic tracheitis with a
slow resolution pattern.
We observed a histological pattern of erosive inflammation of the respiratory
epithelium.
Planned tracheo-bronchoscopy and tracheal toilettes are recommended to prevent
critical obstruction of the airway, which can be fatal in patients with associated
impairment of lung function caused by SARS-CoV-2 infection.
The present cases highlight the need for close interdisciplinary working and
communication in the management of airway complications of COVID-19 infection
Vulnerability to motor fuel price increases: Socio-spatial patterns in England
In high-motorisation, car-dependent countries, transport affordability is intimately linked to the price of oil derived motor fuels, which may become increasingly volatile in the future due to global oil price movements and environmental taxation. The negative impacts of fuel price spikes in terms of increased household expenditure and economic stress are unevenly spatially and socially distributed. Previous research has found that vulnerability to fuel price increases is higher in peripheral, peri-urban and rural areas, and that low income tends to be co-located with high car dependence and low vehicle fuel efficiency, with a compounding effect on vulnerability. The goal of this article is to test these hypotheses for England, providing new evidence on spatial patterns of vulnerability to fuel price increases at the small-area level. We propose a composite vulnerability indicator combining data on income, accessibility, vehicle inspection and vehicle registration for 2011. Within English city-regions, we find little evidence of the socially regressive patterns previously identified in the literature. This is explained by the persistent concentration of poverty in urban cores, as well as by the poor fuel economy of the vehicle fleet in wealthier areas, due to the prevalence of powerful vehicles there. On the other hand, our analysis suggests that the impacts of fuel price increases would be very unequal between city-regions, as the least sensitive metropolitan area (Greater London) is also characterised by high levels of adaptive capacity. We conclude by setting out an agenda for future research on spatial vulnerability to fuel price increases
The effects of ageing on dental pulp stem cells, the tooth longevity elixir
Stem cells are essential for tissue homeostasis and regeneration throughout the lifespan of multicellular rganisms. The decline in stem cell function during advanced age is associated with a reduced regenerative potential of tissues that leads to an increased frequency of diseases. Age-related changes also occur in the dental pulp tissue that represents a reliable model tissue, with high regenerative capability, for studying senescence mechanisms. However, little information is available concerning the effects of ageing on dental stem-cell function. In this mini-review, recent data on how the molecular and functional alterations that accumulate in stem cell populations during ageing result in modifications of dental pulp physiology are discussed. Changes that accumulate during ageing such as how reduction of pulp chamber volume, decreased vascular supply and modifications to the stem cell niches affect stem cell functions and, therefore, dental pulp regenerative potential in response to various stressful agents. Dental pulp cells from aged individuals are still metabolically active and secrete pro-inflammatory and matrix-degrading molecules. Furthermore, miRNAs and exosomes derived from dental pulp stem cells constitute an attractive source of nanovesicles for the treatment of age-related dental pathologies. Further investigation of the epigenetic alterations in dental pulp stem cells, accumulating during ageing, might reveal crucial information for potential stem cell-based therapeutic approaches in the elderly
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