900 research outputs found
Behaviour and performance of lactating sows housed in different types of farrowing rooms during summer
AbstractThirty mixed-parity Landrace×Large White sows were used to evaluate the effects of the type of farrowing room on 28-day lactation behaviour under tropical conditions during summer. The sows were allocated in a completely randomised design with three treatments with 10 replicates according to parity number and body weight, with each animal being considered an experimental unit. The treatments consisted of a conventional farrowing room (T1); a conventional farrowing room with floor cooling under the sow (T2); and a semi-outdoor farrowing room without a cage and with access to a fenced field (T3). The sows from T1 and T2 groups were exposed to mean maximum and minimum environmental temperatures of 25.7 and 21.0°C, respectively, and the sows from the T3 group to average maximum and minimum environmental temperatures of 26.5 and 20.7°C, respectively. The feed consumption of T3 sows was numerically higher than the T1 and T2 sows (+9.5% on average). The body-weight loss was influenced at 28days (P<0.10) by treatment, being that the T3 sows gained weight (+4.7kg) while the T1 and T2 sows lost weight (−11.9 and −3.7kg, respectively for T1 and T2). The T3 sows showed a higher percentual litter mortality than the T1 and T2 sows (3.2% vs. 0% vs. 7.8%, respectively for T1, T2 and T3 sows). From farrowing until day 28 of lactation, the T2 and T3 sows showed higher lactation efficiency when compared with the T1 sows (72% vs. 87% vs. 88%, respectively for T1, T2 and T3 sows). The T1 sows showed higher (P<0.01) frequencies of visits to the feeder and drinker (+38% on average). The T3 sows spent more time (P<0.01) at the drinker than T1 and T2 sows (23 vs. 23 vs. 32min, respectively for T1, T2 and T3 sows). The T3 sows showed a higher (P<0.10) frequency of nursing than the other treatments (+15% on average). T1 and T2 sows were found to spend more time (P<0.01) performing other postures during 24h than sows maintained in T3 (50 vs. 51 vs. 22min/d, respectively for T1, T2 and T3). It is concluded that cooling of the floor under the sow in the conventional farrowing room or the use of semi-outdoor farrowing rooms improves the thermal environment and the lactation efficiency of the sows housed in hot ambient temperatures at 28-day lactation in the summer period, indicating an improved welfare
Exact time-dependent correlation functions for the symmetric exclusion process with open boundary
As a simple model for single-file diffusion of hard core particles we
investigate the one-dimensional symmetric exclusion process. We consider an
open semi-infinite system where one end is coupled to an external reservoir of
constant density and which initially is in an non-equilibrium state
with bulk density . We calculate the exact time-dependent two-point
density correlation function and the mean and variance of the integrated average net flux
of particles that have entered (or left) the system up to time .
We find that the boundary region of the semi-infinite relaxing system is in a
state similar to the bulk state of a finite stationary system driven by a
boundary gradient. The symmetric exclusion model provides a rare example where
such behavior can be proved rigorously on the level of equal-time two-point
correlation functions. Some implications for the relaxational dynamics of
entangled polymers and for single-file diffusion in colloidal systems are
discussed.Comment: 11 pages, uses REVTEX, 2 figures. Minor typos corrected and reference
17 adde
Onion yield under agroecological farming system using distinct irrigation depths and soil covers
Search for a Higgs Boson Decaying to Weak Boson Pairs at LEP
A Higgs particle produced in association with a Z boson and decaying into
weak boson pairs is searched for in 336.4 1/pb of data collected by the L3
experiment at LEP at centre-of-mass energies from 200 to 209 GeV. Limits on the
branching fraction of the Higgs boson decay into two weak bosons as a function
of the Higgs mass are derived. These results are combined with the L3 search
for a Higgs boson decaying to photon pairs. A Higgs produced with a Standard
Model e+e- --> Zh cross section and decaying only into electroweak boson pairs
is excluded at 95% CL for a mass below 107 GeV
Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV
Results are presented from a search for a W' boson using a dataset
corresponding to 5.0 inverse femtobarns of integrated luminosity collected
during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV.
The W' boson is modeled as a heavy W boson, but different scenarios for the
couplings to fermions are considered, involving both left-handed and
right-handed chiral projections of the fermions, as well as an arbitrary
mixture of the two. The search is performed in the decay channel W' to t b,
leading to a final state signature with a single lepton (e, mu), missing
transverse energy, and jets, at least one of which is tagged as a b-jet. A W'
boson that couples to fermions with the same coupling constant as the W, but to
the right-handed rather than left-handed chiral projections, is excluded for
masses below 1.85 TeV at the 95% confidence level. For the first time using LHC
data, constraints on the W' gauge coupling for a set of left- and right-handed
coupling combinations have been placed. These results represent a significant
improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
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