815 research outputs found
A new species of Pliosaurus (Sauropterygia: Plesiosauria) from the Middle Volgian of central Spitsbergen, Norway
Eight seasons of fieldwork in the Upper Jurassic black shales of the Slottsmøya Member of the Agardhfjellet Formation (Upper Jurassic; Middle Volgian) in the Arctic archipelago of Svalbard have yielded numerous skeletal remains of plesiosaurs and ichthyosaurs. Among the new discoveries from the Slottsmøya Member are two very large specimens of short-necked plesiosaurians. Dental and postcranial morphology suggest that they represent a new species of the genus Pliosaurus, a taxon known from several specimens of Kimmeridgian and Tithonian-aged strata in England, France and Russia. Skeletal dimensions of this new taxon suggest that it was one of the largest members of the Pliosauridae and that it possessed comparatively longer front limbs than other known pliosaurid
Invariant construction of solutions to Einstein's field equations - LRS perfect fluids II
The properties of LRS class II perfect fluid space-times are analyzed using
the description of geometries in terms of the Riemann tensor and a finite
number of its covariant derivatives. In this manner it is straightforward to
obtain the plane and hyperbolic analogues to the spherical symmetric case. For
spherically symmetric static models the set of equations is reduced to the
Tolman-Oppenheimer-Volkoff equation only. Some new non-stationary and
inhomogeneous solutions with shear, expansion, and acceleration of the fluid
are presented. Among these are a class of temporally self-similar solutions
with equation of state given by , and a class of
solutions characterized by . We give an example of geometry
where the Riemann tensor and the Ricci rotation coefficients are not sufficient
to give a complete description of the geometry. Using an extension of the
method, we find the full metric in terms of curvature quantities.Comment: 24 pages, 1 figur
The Stability of an Isentropic Model for a Gaseous Relativistic Star
We show that the isentropic subclass of Buchdahl's exact solution for a
gaseous relativistic star is stable and gravitationally bound for all values of
the compactness ratio , where is the total mass and is
the radius of the configuration in geometrized units] in the range, , corresponding to the {\em regular} behaviour of the solution. This
result is in agreement with the expectation and opposite to the earlier claim
found in the literature.Comment: 9 pages (including 1 table); accepted for publication in GR
Genetic homogeneity in the deep-sea grenadier Macrourus berglax across the North Atlantic Ocean
Paucity of data on population structure and connectivity in deep sea species remains a major obstacle to their sustainable management and conservation in the face of ever increasing fisheries pressure and other forms of impacts on deep sea ecosystems. The roughhead grenadier Macrourus berglax presents all the classical characteristics of a deep sea species, such as slow growth and low fecundity, which make them particularly vulnerable to anthropogenic impact, due to their low resilience to change. In this study, the population structure of the roughhead grenadier is investigated throughout its geographic distribution using two sets of molecular markers: a partial sequence of the Control Region of mitochondrial DNA and species-specific microsatellites. No evidence of significant structure was found throughout the North Atlantic, with both sets of molecular markers yielding the same results of overall homogeneity. We posit two non-mutually exclusive scenarios that can explain such outcome: i) substantial high gene flow among locations, possibly maintained by larval stages, ii) very large effective size of post-glacially expanded populations. The results can inform management strategies in this by-caught species, and contribute to the broader issue of biological connectivity in the deep ocean
Effect of Morning, Evening or Twice Daily Feeding on Yearling Steer Performance
The impact of morning (0730), evening (1 600), and twice daily (0730/1600) feeding on feedlot performance was evaluated in yearling steers fed high grain diets. Exp. 1 was conducted from July 20 to October 12, 1993. The 92% concentrate diets were based on dry whole shelled corn. There were four pen replicates per treatment. Exp. 2 was conducted from January 6 to May 10, 1994. The 93% concentrate diets were based on a 50/50 blend of dry whole shelled corn and high moisture corn. There were six pen replicates per treatment. In Exp. 1 evening feeding increased (P\u3c.06) average daily gain and improved (P\u3c .06) feed/gain over morning feeding. The most pronounced effects were during the initial 28 days of the 84-day experiment. Performance of steers fed twice daily was intermediate to evening and morning treatments. Twice daily feeding improved performance over morning feeding (average daily gain, P\u3c.10; feed/gain P\u3c.01). Most of this response occurred during the final 28 days of the experiment. During Exp. 2 there were treatment effects on interim period performance but no responses (P\u3e.10) occurred for cumulative performance variables
Non-adiabatic radiative collapse of a relativistic star under different initial conditions
We examine the role of space-time geometry in the non-adiabatic collapse of a
star dissipating energy in the form of radial heat flow, studying its evolution
under different initial conditions. The collapse of a star with interior
comprising of a homogeneous perfect fluid is compared with that of a star
filled with inhomogeneous imperfect fluid with anisotropic pressure. Both the
configurations are spherically symmetric, however, in the latter case, the
physical space of the configurations is assumed to be
inhomogeneous endowed with spheroidal or pseudo-spheroidal geometry. It is
observed that as long as the collapse is shear-free, its evolution depends only
on the mass and size of the star at the onset of collapse.Comment: To appear in Pramana- j. of physic
Re-evaluation of behenic acid from mustard seeds to be used in the manufacturing of certain emulsifiers pursuant to Article 21(2) of Regulation (EU) No 1169/2011 – for permanent exemption from labelling
Following a request from the European Commission, the Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to review a scientific assessment related to a notification from DuPont Nutrition Biosciences Aps on behenic acid from mustard seeds to be used in the manufacturing of certain emulsifiers pursuant to Article 21(2) of Regulation (EU) No 1169/2011 – for permanent exemption from labelling. The EC requested EFSA to consider comments raised by the German authorities in relation to: (a) the maximum amount of mustard protein that could be consumed from the emulsifiers manufactured from behenic acid (E470a, E471 and E477) on a single occasion and (b) the minimal observed eliciting dose (MOED) triggering allergic reactions in mustard-allergic individuals. The maximum amount of mustard protein content in behenic acid was re-assessed in view of new analytical data provided by the applicant. Intake estimates by the EFSA ANS Panel for E471 (adults) were used as a proxy for the combined intake (E470a, E471 and E477). Food challenge data and systematic reviews thereof deriving population minimal observed eliciting dose distributions for mustard protein were used to calculate the MOED and estimate the risk. The margin of exposure between the MOED (0.26 mg mustard protein) and the maximum amount of mustard protein that could be consumed from the emulsifiers on a single occasion (0.00895475 mg) is 29. It is predicted that between 0.1% and 1% of the mustard allergic population would react with mild objective symptoms to that dose. Overall, the assessment is conservative, particularly in relation to the exposure. Based on the information and data available, the NDA Panel concludes that it is extremely unlikely (≤ 1% probability) that oral consumption of emulsifiers to be manufactured using behenic acid from mustard seeds (i.e. E470a, E471 and E477) will trigger an allergic reaction in mustard-allergic individuals under the proposed conditions of use
Scientific Opinion related to a notification from Lyckeby Starch AB on barley starch to be used in the manufacturing of several foods as ingredient, of the food additive modified starch and of glucose syrups pursuant to Article 21(2) of Regulation (EU) No 1169/2011 – for permanent exemption from labelling
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on barley starch to be used in the manufacturing of several foods as ingredient, of the food additive modified starch and of glucose syrups pursuant to Article 21(2) of Regulation (EU) No 1169/2011, as notified by Lyckeby Starch AB. The applicant provided information on the manufacturing process and data on the content of total protein, gluten and allergenic proteins in barley starch. The applicant also performed IgE-binding in vitro tests, which were considered inconclusive by the Panel. No human intervention studies with barley starch or food products thereof were provided by the applicant, except for a DBPCFC with barley starch hydrolysate in cereal allergic individuals. The Panel notes that glucose syrups based on barley have been already exempted from allergen labelling as per Annex II of Regulation (EU) No 1169/2011 and that the current application is for the exemption from labelling of all foods manufactured from barley starch. In all the scenarios considered for the anticipated intake, the calculated total protein intake from barley starch was above the MED/MOED for wheat (expressed in mg of wheat protein) in adults (10 mg) and children (2 mg). The Panel concludes that the data available are insufficient to conclude on the likelihood of adverse allergic reactions in cereal-allergic individuals upon consumption of barley starch under the conditions of use proposed by the applicant, and that the consumption of foodstuffs produced from barley starch as starting (raw) material or foodstuffs containing barley starch as an ingredient is unlikely to cause an adverse reaction in individuals with coeliac disease who are not allergic to cereals, provided that the value of gluten for ‘gluten-free’ foods (20 mg/kg) is not exceeded
Bifidobacterium animalis subsp. lactis Bi-07 contributes to increasing lactose digestion: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006
Following an application from DuPont Nutrition Biosciences ApS submitted for authorisation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Ireland, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to Bifidobacterium animalis subsp. lactis Bi-07 (Bi-07) and contribution to increasing lactose digestion. The scope of the application was proposed to fall under a health claim based on newly developed scientific evidence. The food proposed by the applicant as the subject of the health claim is Bi-07. The Panel considers that Bi-07 is sufficiently characterised. The claimed effect proposed by the applicant is \u2018improvement of lactose digestion\u2019. The Panel considers that increasing lactose digestion is a beneficial physiological effect for individuals with lactose maldigestion provided that the symptoms of lactose maldigestion are improved. Two human intervention studies which investigated a single dose effect of Bi-07 on lactose digestion using the hydrogen breath test, as well as on gastrointestinal symptoms were submitted. These studies show that consumption of Bi-07 (1012 CFU) increases lactose digestion in individuals with lactose maldigestion and that Bi-07 exhibits lactase activity in vitro. However, these studies provide no evidence that increasing lactose digestion through the consumption of Bi-07 (1012 CFU) improves gastrointestinal symptoms of lactose maldigestion, which is considered a beneficial physiological effect. The Panel concludes that a cause and effect relationship has not been established between the consumption of Bifidobacterium animalis subsp. lactis Bi-07 and a beneficial physiological effect (i.e. the improvement of symptoms of lactose maldigestion) in individuals with lactose maldigestion
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