701 research outputs found
Compared Productivity of Local Ecotypes and Selected Cultivars of Perennial Ryegrass (Lolium Perenne) in High Belgium
The objective of the trials was to compare the productivity of local ecotypes of perennial ryegrass (Lolium perenne) issued from old permanent pastures of High Belgium to that of adapted cultivars. During 3 consecutive years 2 local ecotypes were compared, in pure seedling at 2 different levels of nitrogenous manure, to 2 cultivars frequently used in seed mixtures for pastures. Results obtained using a cutting cycle wich simulated grazing did not reveal significant differences in terms of forage production or feeding value. These results explain the weak increase in forage production recorded in pastures renovated by reseeding as compared to non-renovated pastures under the same environmental conditions
Monitoring of Intake and Energetic Efficiency of the Grass in a Pasture Rotationally Grazed by Bulls using NIRS Applied to the Faeces
The objective of this approach was to characterise variations that one can observe in the course of a pasture season using near infrared spectrometry (NIRS) applied to the analysis of the grass and faeces collected during the season. Available grass and faeces of Belgian Blue White young bulls have been collected 3 times a week since the beginning of May until mid-October. The samples have been predicted in NIRS technique according to a calibration previously developed on the faeces of sheep fed ad libitum in cage with green grass. The NIRS provides a useful tool to provide a relative description and a monitoring of the evolution of the quality and of the daily intake of grass, that could provide useful information to adapt the supplementation according to the changing quality of the grass
Building Decision Tools for Sustainable Grassland Management: A Case Study of Participatory Research in La RĂŠunion
During the last 30 years, cattle breeding has developed in La Reunion Island (France, Indian Ocean) with strong support from local authorities and extension structures. The Union des Associations FoncieĚres Pastorales (UAFP) initiated and still sustain a large effort on grassland improvement. During the same period, CIRAD managed different research programmes on agronomic aspects of pasture management). Scarcity of space, the volcanic soil and tropical climatic conditions contributed to repeated forage shortages during the dry season, making forage production a major issue for cattle breeders. In 1991, CIRAD launched a research programme to elaborate decision tools for assessing and improving pasture management. A partnership was developed with UAFP, with the local institution being involved in the elaboration of the tools and now being completely in charge of their use to advise cattle breeders on pasture management
The reduction of chromate ions by Fe(II) layered hydroxides
International audienceThe reduction of chromate ions by Fe(OH)2 and the iron (II)-iron (III) hydroxysulphate green rust, GR(SO42-), was studied to evaluate whether such synthetic layered hydroxides and the corresponding natural green rust mineral could be involved in the natural attenuation of contaminated environments. The resulting Cr (III) bearing phases, which would govern the subsequent behaviour of chromium, were clearly characterised. Both compounds proved to be very reactive and oxidised instantaneously while chromate ions were reduced to Cr (III) as evidenced by X-ray photoelectron spectroscopy. Mass balance (ICP-AES) demonstrated that the Fe/Cr ratio inside the solid end product was equal to the initial Fe/Cr ratio. The solid phases, analysed by X-ray diffraction, Raman and Mossbauer spectroscopies were identified as Cr-substituted poorly crystallised iron (III) oxyhydroxides in both cases, more precisely d-FeOOH when starting with Fe(OH)2 and ferrihydrite when starting with GR(SO42-)
Measurement of the Spectroscopy of Orbitally Excited B Mesons at LEP
We measure the masses, decay widths and relative production rate of orbitally
excited B mesons using 1.25 million hadronic Z decays recorded by the L3
detector. B-meson candidates are inclusively reconstructed and combined with
charged pions produced at the primary event vertex. An excess of events above
the expected background in the B\pi mass spectrum in the region 5.6-5.8 GeV is
interpreted as resulting from the decay B_u,d^** -> B^(*)\pi, where B_u,d^**
denotes a mixture of l=1 B-meson states containing a u or a d quark. A fit to
the mass spectrum yields the masses and decay widths of the B_1^* and B_2^*
spin states, as well as the branching fraction for the combination of l=1
states. In addition, evidence is presented for the existence of an excited
B-meson state or mixture of states in the region 5.9-6.0 GeV
Search for Charged Higgs Bosons in e+e- Collisions at \sqrt{s} = 189 GeV
A search for pair-produced charged Higgs bosons is performed with the L3
detector at LEP using data collected at a centre-of-mass energy of 188.6 GeV,
corresponding to an integrated luminosity of 176.4 pb^-1. Higgs decays into a
charm and a strange quark or into a tau lepton and its associated neutrino are
considered. The observed events are consistent with the expectations from
Standard Model background processes. A lower limit of 65.5 GeV on the charged
Higgs mass is derived at 95 % confidence level, independent of the decay
branching ratio Br(H^{+/-} -> tau nu)
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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