880 research outputs found
Notes on the frugivorous fruit fly (Diptera: Tephritidae) fauna of western Africa, with description of a new Dacus species
The species richness of the frugivorous fruit fly fauna of western African (in particular of Ivory Coast, Ghana, Togo, Benin and Nigeria) is discussed. The diversity is compared at a national level and between the ecoregions within the national boundaries of the study area. A new species, Dacus goergeni sp. nov. is described and additional taxonomic notes are presented
Milk fatty acid composition and associated rumen lipolysis and fatty acid hydrogenation when feeding forages from intensively managed or semi-natural grasslands
In order to evaluate the effect of replacing intensive forage by semi-natural grassland products on rumen lipid metabolism and milk fatty acid composition, four lactating and rumen canulated Holstein cows were used in a 4Ă4 Latin square design. Four different diets were fed: diet 100 IM - 100% intensively managed silage (IM), diet 20 SPP - 80% IM plus 20% semi-natural but species poor silage (SPP), diet 60 SPP - 40% IM plus 60% SPP and diet 60 SPR - 40% IM plus 60% semi-natural species rich silage (SPR). The silages showed significant differences in total fat content and in proportions of C18:2 n-6 and C18:3 n-3. Despite the reduced dietary supply of C18:3 n-3 with diets 60 SPP and 60 SPR, differences in milk C18:3 n-3 were small, suggesting higher recoveries of C18:3 n-3. Presumably, the latter are related to a higher transfer efficiency of C18:3 n-3 from the duodenum to the mammary gland, since rumen biohydrogenation, estimated from rumen pool size and first order rumen clearance kinetics, were similar among diets. CLA c9t11 in milk from cows fed diet 60 SPR were almost doubled compared to feeding one of the other diets. This has been related to the partial inhibition of rumen biohydrogenation of C18:3 n-3 and/or C18:2 n-6, as suggested by the increased proportions of hydrogenation isomers and reduced stearic acid proportions in rumen pool samples. In conclusion, the results suggest that the use of semi-natural grasslands in the diet of the animals reduce to some extent complete rumen biohydrogenation, which leads to an increase in milk CLA
Inspiratory muscle training improves breathing pattern during exercise in COPD patients (letter).
The addition of IMT to a PR programme for selected COPD patients changes breathing pattern during exercise
A faster pseudo-primality test
We propose a pseudo-primality test using cyclic extensions of . For every positive integer , this test achieves the
security of Miller-Rabin tests at the cost of Miller-Rabin
tests.Comment: Published in Rendiconti del Circolo Matematico di Palermo Journal,
Springe
Morita base change in Hopf-cyclic (co)homology
In this paper, we establish the invariance of cyclic (co)homology of left
Hopf algebroids under the change of Morita equivalent base algebras. The
classical result on Morita invariance for cyclic homology of associative
algebras appears as a special example of this theory. In our main application
we consider the Morita equivalence between the algebra of complex-valued smooth
functions on the classical 2-torus and the coordinate algebra of the
noncommutative 2-torus with rational parameter. We then construct a Morita base
change left Hopf algebroid over this noncommutative 2-torus and show that its
cyclic (co)homology can be computed by means of the homology of the Lie
algebroid of vector fields on the classical 2-torus.Comment: Final version to appear in Lett. Math. Phy
Thermodynamics of greenhouse systems : a new approach leading to new proposals for sustainable production
Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.Greenhouse production systems produce in the Netherlands
and Flanders economical important quantities of vegetables,
fruit and ornamentals. Control of the crop environment has led
to a high primary energy use (1500MJ/mÂČ/year). This high
primary energy use affects the economical and environmental
sustainability. Research projects in the Netherlands and
Flanders are launched to achieve sustainable greenhouse
systems with high crop yields and low primary energy use.
Until now, these projects didnât result in the desired primary
energy savings. On the contrary, the civil building industry
succeeds by the passive house technology in a magnitudeâs
reduction for primary energy use.
The primary energy saving research in greenhouse systems
was mainly based on analysis of energy balances. However, the
thermodynamic theory indicates that an analysis based on the
concept of exergy (free energy) and energy is preferred. Such
analysis could reveal possibilities for primary energy savings.
The different processes and in/outputs of the greenhouse
system are outlined. The appropriate equations for exergy
calculations are developed. First, analyses are performed on the
processes of transpiration and ventilation. Further, a total
system assessment is performed.
The exergy analysis indicates that primary energy saving in
greenhouse systems could be the same as in the building
industry, but adapted technologies need to be developed.
The Institute for Agricultural and Fisheries Research
(ILVO) will use this exergy analysis as a basis for the
development of an exergy efficient greenhouse prototype
(EXEkas).mp201
Response of CsI(Tl) scintillators over a large range in energy and atomic number of ions (Part I): recombination and delta -- electrons
A simple formalism describing the light response of CsI(Tl) to heavy ions,
which quantifies the luminescence and the quenching in terms of the competition
between radiative transitions following the carrier trapping at the Tl
activator sites and the electron-hole recombination, is proposed. The effect of
the delta rays on the scintillation efficiency is for the first time
quantitatively included in a fully consistent way. The light output expression
depends on four parameters determined by a procedure of global fit to
experimental data.Comment: 28 pages, 6 figures, submitted to Nucl. Inst. Meth.
Evidence for Spinodal Decomposition in Nuclear Multifragmentation
Multifragmentation of a ``fused system'' was observed for central collisions
between 32 MeV/nucleon 129Xe and natSn. Most of the resulting charged products
were well identified thanks to the high performances of the INDRA 4pi array.
Experimental higher-order charge correlations for fragments show a weak but non
ambiguous enhancement of events with nearly equal-sized fragments. Supported by
dynamical calculations in which spinodal decomposition is simulated, this
observed enhancement is interpreted as a ``fossil'' signal of spinodal
instabilities in finite nuclear systems.Comment: 4 pages, 4 figures, to be published in Phys. Rev. Letter
Identification and quantification of spinochromes in body compartments of <i>Echinometra mathaei</i>'s coloured types
Sea urchin pigmentation is mainly due to polyhydroxy-1,4-naphthoquinones called spinochromes. If their molecular structures are well known in test and spines of many species, their abundance and distribution in other body compartments remain unstudied. The aim of this study is to analyse the pigment composition in four body compartments (test/spines, digestive system, gonads and coelomic fluid) of four coloured types of the sea urchin Echinometra mathaei. Qualitative and quantitative measurements by mass spectrometry highlight the existence of 13 different pigments; among which are five isomers of known spinochromes as well as three potentially new ones. The composition comparison shows the largest spinochrome diversity in âtest/spinesâ body compartments. The spinochrome concentrations vary from 48 to 1279 mg kgâ1 of dried body compartment. It is the highest in the digestive system, although it is also important in the organic fraction of the âtest/spinesâ body compartment. This observation may be explained by higher exposures of some body compartments to external environments and by the protective role fulfilled by spinochromes against microorganisms, ultraviolet radiation and reactive oxygen species. The âblackâ typeâthe most common coloured type in coral reefsâhas the highest concentration of spinochromes indicating their importance in Echinoids' fitness by acting as a protective agent
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Thinking about a limited future enhances the positivity of younger and older adultsâ recall: support for socioemotional selectivity theory
Compared with younger adults, older adults have a relative preference to attend to and remember positive over negative information. This is known as the âpositivity effect,â and researchers have typically evoked socioemotional selectivity theory to explain it. According to socioemotional selectivity theory, as people get older they begin to perceive their time left in life as more limited. These reduced time horizons prompt older adults to prioritize achieving emotional gratification and thus exhibit increased positivity in attention and recall. Although this is the most commonly cited explanation of the positivity effect, there is currently a lack of clear experimental evidence demonstrating a link between time horizons and positivity. The goal of the current research was to address this issue. In two separate experiments, we asked participants to complete a writing activity, which directed them to think of time as being either limited or expansive (Experiments 1 and 2) or did not orient them to think about time in a particular manner (Experiment 2). Participants were then shown a series of emotional pictures, which they subsequently tried to recall. Results from both studies showed that regardless of chronological age, thinking about a limited future enhanced the relative positivity of participantsâ recall. Furthermore, the results of Experiment 2 showed that this effect was not driven by changes in mood. Thus, the fact that older adultsâ recall is typically more positive than younger adultsâ recall may index naturally shifting time horizons and goals with age
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