Four new species of deep water agglutinated foraminifera from the Oligocene-Miocene of the Congo Fan (offshore Angola)

Four new species of deep-water agglutinated benthic foraminifera are described from the Oligocene and Miocene of the Congo Fan, offshore Angola. Scherochorella congoensis n.sp., Paratrochamminoides goroyskiformis n.sp., Haplophragmoides nauticus n.sp. and Portatrochammina profunda n.sp. all occur in deep-sea turbiditic shales and sands from the distal section of the Congo Fan

Character space restrictions and boundary conditions in the evolution of quantitative multistate characters.

The effects of restrictions of available character space on the mean morphological distance between living members of evolutionary phylads are examined by Monte Carlo simulation. The approach involves specifying the degree to which ancestor-descendant species may differ and limiting the range of attainable character states within a phylad. Morphological evolution is modeled as a Markovian process involving quantitative multistate characters. States for a given character are allowed to evolve at time-dependent or speciation-dependent rates. The final distributions of morphological distance for a given trait among members of a phylad depend on the number of species in the phylad, the rate and pattern of evolution of new character states, and the existence of boundary conditions indicating possible selective constraints on the trait. When morphological change is proportional to time, increasing restrictions on character evolution tend to (a) lower mean distance between species and (b) leave the ratio of mean distances ( DR Dp) in species-rich vs. species-poor phylads of comparable evolutionary age near one. When change is proportional to rate of speciation, similar restrictions tend to (a) limit mean distance only in phylads in which the number of speciations exceeds the range of attainable character states and (b) permit DR Dp to be considerably greater than one, except in extreme cases. Implications of these results for the current phyletic gradualism-rectangular evolution controversy are considered. © 1979

Effects of seawater alkalinity on calcium and acid-base regulation in juvenile European lobster (Homarus gammarus) during a moult cycle

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Fluxes of NH4(+) (acid) and HCO3(-) (base), and whole body calcium content were measured in European lobster (Homarus gammarus) during intermoult (megalopae stage), and during the first 24h for postmoult juveniles under control (~2000μeq/L) and low seawater alkalinity (~830μeq/L). Immediately after moulting, animals lost 45% of the total body calcium via the shed exoskeleton (exuvia), and only 11% was retained in the uncalcified body. At 24h postmoult, exoskeleton calcium increased to ~46% of the intermoult stage. Ammonia excretion was not affected by seawater alkalinity. After moulting, bicarbonate excretion was immediately reversed from excretion to uptake (~4-6 fold higher rates than intermoult) over the whole 24h postmoult period, peaking at 3-6h. These data suggest that exoskeleton calcification is not completed by 24h postmoult. Low seawater alkalinity reduced postmoult bicarbonate uptake by 29% on average. Net acid-base flux (equivalent to net base uptake) followed the same pattern as HCO3(-) fluxes, and was 22% lower in low alkalinity seawater over the whole 24h postmoult period. The common occurrence of low alkalinity in intensive aquaculture systems may slow postmoult calcification in juvenile H. gammarus, increasing the risk of mortalities through cannibalism.The authors would like to acknowledge and thank Dom Boothroyd and Carly Daniels at the National Lobster Hatchery (Padstow, North Cornwall, U.K.) for provision of animals used in this research, and for the valuable comments made by the anonymous reviewers of this manuscript. The analytical equipment used in these experiments were funded through BBSRC and NERC grants to RWW (BB/F009364/1, NE/H010041/1 and BB/J00913X/1)

Oligocene Deep-Water Agglutinated Foraminifera from the Congo Fan, Offshore Angola: Palaeoenvironments and Assemblage Distributions

Seventh International Workshop on Agglutinated Foraminifera, Urbino, Italy, October 2-8, 2005Agglutinated foraminiferal assemblages from the Oligocene section of an exploration well drilled in the distal part of the Congo Fan are fully documented and interpreted for palaeoenvironment. A total of 65 ditch cutting samples were analysed at 10 m intervals, from 3630 to 4270 m below rotary table. An average of 170 specimens were extracted per sample, with over 100 species being documented and described using SEM and light photography. The results reveal the most taxonomically diverse deepsea Oligocene fauna yet described. Six assemblages have been defined and analysed with Correspondence and 'Morphogroup' Analysis. These are 1. Nothia robusta / Reticulophragmium Assemblage (4110-4270 m), 2. Nothia robusta / Scherochorella congoensis / Discamminoides sp. 1 Assemblage (4000-4100 m), 3. High diversity Reticulophragmium Assemblage (3870-3990 m), 4. Portatrochammina profunda Assemblage (3790-3860 m), 5. Nothia latissima Assemblage (3730-3780 m) and 6. Low abundance Assemblage (3630-3720 m). Palaeobathymetric estimates range from middle - lower bathyal based on comparison with living taxa and morphogroup distributions. These results extend the known stratigraphic range (last occurrences) of Reticulophragmium amplectens into the Oligocene in the Atlantic, and possibly also Paratrochamminoides gorayskii, Paratrochamminoides olszewskii, Trochamminoides aff. proteus, Trochamminoides subcoronatus, Haplophragmoides horridus and Haplophragmoides walteri, although reworking is documented with these species. Results also extend the known first occurrences of Recurvoides azuaensis, Spiropsammina primula, Cyclammina aff. orbicularis, Discamminoides sp. and Glaphyrammina americana into the Oligocene. Large scale variations within faunas are largely assigned to documented variations in sand content, where higher proportions of sand generally coincide with reduced diversity and abundance along with a dominance of opportunistic species such as Nothia robusta, Nothia latissima and Ammodiscus latus. A major excursion in the infaunal morphogroup, suspension-feeding morphogroup and diversity and abundance within Assemblage 2 is termed the 'Scherochorella Event', and does not correlate with an increase in sand. This fauna is thought to be the result of lower oxygen conditions allowing the dominance of the low oxygen morphotype Scherochorella congoensis and the opportunistic species Nothia robusta. Deep-water circulation in the Atlantic at this time is generally thought to have been strong, and this event suggests that there may have been a temporary expansion of the oxygen minimum zone during the Late Oligocene, coinciding with increased benthic δ18O values, global cooling, and increased upwelling associated with a stronger polar front. The otherwise high diversity of the fauna in the well supports the interpretation of well-oxygenated conditions.We would like to thank BP Exploration for their support in fully funding this project

P652The cardioprotective effect of exogenous sphingosine-1-phosphate requires the activation of endogenous sphingosine-1-phosphate via the sphingosine kinase 1

Purpose: Exogenous administration of sphingosine-1-phosphate (S1P) alone, or as part of high density lipoprotein, protects against myocardial infarction. S1P-induced cardioprotection targets the inhibition of the mitochondrial permeability transition pore via mechanisms that remain unclear. In the cell, the endogenous production of S1P from sphingosine is dependent on the activation of sphingosine kinases (SphK) 1 and 2. These two kinases play a role in cardioprotection against ischemia-reperfusion (IR) injury. Therefore, we hypothesised that the cardioprotective effect of exogenous S1P requires the activation of endogenous S1P via SphK. Methods: Isolated cardiomyocytes from adult wildtype mice were exposed to 2 hours of simulated ischemia (SI) in the presence of S1P (10nM) with/without N,N-dimethylsphingosine (DMS, a SphK1 and 2 inhibitor, 10μM) or SKI (a specific SphK1 inhibitor, 15μM). Cell viability was assessed using trypan blue staining and normalised to the normoxic control. Isolated perfused hearts from adult wildtype mice were exposed to 35 minutes of global ischemia followed by 45 minutes of reperfusion (IR) in the presence of S1P (10nM) with/without SKI (10μM). Infarct size (IS) was assessed using tripheyltetrazolium chloride staining and SphK1 activity using a specific biochemical fluorescence based assay kit. Both parameters were normalised to the IR control. Results: In isolated cardiomyocytes, viability under normoxic conditions was 76±1%. SI reduced viability to 52±1% (p< 0.001 vs. normoxia). Pre-treatment with S1P restored the viability to 75±1% (p<0.001 vs. SI). The beneficial effect of S1P was partially inhibited in the presence of DMS (67±4%) (ns vs. S1P) and totally abrogated with SKI pre-treatment (54±2%). Similarly, pre-treatment with S1P in isolated hearts reduced IS following IR from 50±1% (IR control) to 31±2% (S1P) (p<0.001 vs. control). Pre-treatment with SKI abrogated the cardioprotective effect of S1P (56±8%) (p<0.05 vs. S1P) as well as the S1P-induced increase in SphK1 activity (from S1P: 196±79 arbitrary units (AU) to SKI+S1P: 53±27 AU, p<0.05 vs. S1P). Conclusions: Our data, performed in both isolated cardiomyocytes and isolated hearts subjected to an ischemia/reperfusion insult, strongly suggest that exogenous sphingosine-1-phosphate-induced cardioprotection is dependent on the activation of endogenous sphingosine-1-phosphate via sphingosine kinase

Isogeometric analysis of fluid-saturated porous media including flow in the cracks

An isogeometric model is developed for the analysis of fluid transport in pre-existing faults or cracks that are embedded in a fluid-saturated deformable porous medium. Flow of the interstitial fluid in the porous medium and fluid transport in the discontinuities are accounted for and are coupled. The modelling of a fluid-saturated porous medium in general requires the interpolation of the displacements of the solid to be one order higher than that of the pressure of the interstitial fluid. Using order elevation and Bézier projection, a consistent procedure has been developed to accomplish this in an isogeometric framework. Particular attention has also been given to the spatial integration along the isogeometric interface element in order to suppress traction oscillations that can arise for certain integration rules when a relatively high dummy stiffness is used in a poromechanical model. © 2016 The Authors. International Journal for Numerical Methods in Engineering Published by John Wiley & Sons Ltd

'Dressage Is Full of Queens!' Masculinity, Sexuality and Equestrian Sport

Attitudes towards sexuality are changing and levels of cultural homophobia decreasing, yet there remain very few openly gay men within sport. As a proving ground for heteromasculinity, sport has traditionally been a hostile environment for gay men. This article is based on an ethnographic study within a sporting subworld in which gay men do appear to be accepted: equestrian sport. Drawing on inclusive masculinity theory, equestrian sport is shown to offer an unusually tolerant environment for gay men in which heterosexual men of all ages demonstrate low levels of homophobia. Inclusive masculinity theory is a useful framework for exploring the changing nature of masculinities and this study demonstrates that gay men are becoming increasingly visible and accepted within once unreceptive locales, such as sport and rural communities. However, this more tolerant attitude is purchased at the expense of a subordinated feminine Other, perpetuating the dominance of men within competitive sport. © The Author(s) 2012

Chemical characteristics of air from different source regions during the second Pacific Exploratory Mission in the Tropics (PEM-Tropics B)

Ten-day backward trajectories are used to determine the origins of air parcels arriving at locations of airborne DC-8 chemical measurements during NASA's second Pacific Exploratory Mission in the Tropics B that was conducted during February-April 1999. Chemical data at sites where the trajectories had a common geographical origin and transport history are grouped together, and statistical measures of chemical characteristics are computed. Temporal changes in potential temperature are used to determine whether trajectories experienced a significant convective influence during the 10-day period. Trajectories describing the aged marine Southern Hemispheric category remain over the South Pacific Ocean during the 10-day period, and their corresponding chemical signature indicates very clean air. The category aged marine air in the Northern Hemisphere is found to be somewhat dirtier. Subdividing its trajectories based on the direction from which the air had traveled is found to be important in explaining the various chemical signatures. Similarly, long-range northern hemispheric trajectories passing over Asia are subdivided depending on whether they had followed a mostly zonal path, had originated near the Indian Ocean, or had originated near Central or South America and subsequently experienced a stratospheric influence. Results show that the chemical signatures of these subcategories are different from each other. The chemical signature of the southern hemispheric long-range transport category apparently exhibits the effects of pollution from Australia, southern Africa, and South America. Parcels originating over Central and northern South America are found to contain the strongest pollution signature of all categories, due to biomass burning and other sources. The convective category exhibits enhanced values of nitrogen species, probably due to emissions from lightning associated with the convection. Values of various species, including peroxides and acids, confirm that parcels were influenced by the removal of soluble gas and particle species due to precipitation. Finally, current results are compared with those from the first PEM-Tropics mission that was conducted in the same region during the southern hemispheric dry season (August-October 1996) when extensive biomass burning occurred. Results show that air samples during PEM-Tropics B are considerably cleaner than those of its dry season counterpart. Copyright 2001 by the American Geophysical Union

On the convergence of quadrature formulas connected with multipoint Padé-type approximants

29 pages, no figures.-- MSC2000 codes: 41A55, 41A21.MR#: MR1408352 (97e:41066)Zbl#: Zbl 0856.41027^aLet $I(F)= \int^1_{- 1} F(x)\omega(x) dx$, where $\omega$ is a complex valued integrable function. We consider quadrature formulas for $I(F)$ which are exact with respect to rational functions with prescribed poles contained in \overline{\bbfC}\backslash [- 1, 1]. Their rate of convergence is studied.The research by the first three authors (P.G.-V., M.J.P., R.O.) was partially supported by the HCM project ROLLS, under Contract CHRX-CT93-0416. Research by the fourth author (G.L.L.) was carried out while on a visit at Universidad de La Laguna. This visit was made possible by a travel grant from CDE-IMU.Publicad