133 research outputs found
Early socialization and environmental enrichment of lactating piglets affects the caecal microbiota and metabolomic response after weaning
The aim of this study was to determine the possible impact of early socialization and an enriched neonatal environment to improve adaptation of piglets to weaning. We hypothesized that changes in the microbiota colonization process and in their metabolic response and intestinal functionality could help the animals face weaning stress. A total of 48 sows and their litters were allotted into a control (CTR) or an enriched treatment (ENR), in which piglets from two adjacent pens were combined and enriched with toys. The pattern of caecal microbial colonization, the jejunal gene expression, the serum metabolome and the intestinal physiology of the piglets were assessed before (-2 d) and after weaning (+â3d). A differential ordination of caecal microbiota was observed after weaning. Serum metabolome suggested a reduced energetic metabolism in ENR animals, as evidenced by shifts in triglycerides and fatty acids, VLDL/LDL and creatine regions. The TLR2 gene showed to be downregulated in the jejunum of ENR pigs after weaning. The integration of gene expression, metabolome and microbiota datasets confirmed that differences between barren and enriched neonatal environments were evident only after weaning. Our results suggest that improvements in adaptation to weaning could be mediated by a better response to the post-weaning stress.info:eu-repo/semantics/publishedVersio
Improved W boson mass measurement with the D0 detector
We have measured the W boson mass using the D0 detector and a data sample of
82 pb^-1 from the Tevatron collider. This measurement used W -> e nu decays,
where the electron is close to a boundary of a central electromagnetic
calorimeter module. Such 'edge' electrons have not been used in any previous D0
analysis, and represent a 14% increase in the W boson sample size. For these
electrons, new response and resolution parameters are determined, and revised
backgrounds and underlying event energy flow measurements are made. When the
current measurement is combined with previous D0 W boson mass measurements, we
obtain M_W = 80.483 +/- 0.084 GeV. The 8% improvement from the previous D0
measurement is primarily due to the improved determination of the response
parameters for non-edge electrons using the sample of Z bosons with non-edge
and edge electrons.Comment: submitted to Phys. Rev. D; 20 pages, 18 figures, 9 table
Evidence of Color Coherence Effects in W+jets Events from ppbar Collisions at sqrt(s) = 1.8 TeV
We report the results of a study of color coherence effects in ppbar
collisions based on data collected by the D0 detector during the 1994-1995 run
of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8
TeV. Initial-to-final state color interference effects are studied by examining
particle distribution patterns in events with a W boson and at least one jet.
The data are compared to Monte Carlo simulations with different color coherence
implementations and to an analytic modified-leading-logarithm perturbative
calculation based on the local parton-hadron duality hypothesis.Comment: 13 pages, 6 figures. Submitted to Physics Letters
Search for bottom squarks in pbarp collisions at sqrt(s)=1.8 TeV
We report on a search for bottom squarks produced in pbarp collisions at
sqrt(s) = 1.8 TeV using the D0 detector at Fermilab. Bottom squarks are assumed
to be produced in pairs and to decay to the lightest supersymmetric particle
(LSP) and a b quark with branching fraction of 100%. The LSP is assumed to be
the lightest neutralino and stable. We set limits on the production cross
section as a function of bottom squark mass and LSP mass.Comment: 5 pages, Latex. submitted 3-12-1999 to PRD - Rapid Communicatio
EXPLORE: A Prospective, Multinational, Natural History Study of Patients with Acute Hepatic Porphyria with Recurrent Attacks
BACKGROUND AND AIMS: Acute hepatic porphyria
comprises a group of rare genetic diseases caused by mutations in genes involved in heme biosynthesis. Patients can
experience acute neurovisceral attacks, debilitating chronic
symptoms, and long-term complications. There is a lack of
multinational, prospective data characterizing the disease and
current treatment practices in severely affected patients.
APPROACH AND RESULTS: EXPLORE is a prospective,
multinational, natural history study characterizing disease activity and clinical management in patients with acute hepatic
porphyria who experience recurrent attacks. Eligible patients
had a confirmed acute hepatic porphyria diagnosis and had
experienced â„3 attacks in the prior 12 months or were receiving prophylactic treatment. A total of 112 patients were enrolled and followed for at least 6 months. In the 12 months
before the study, patients reported a median (range) of 6
(0-52) acute attacks, with 52 (46%) patients receiving hemin
prophylaxis. Chronic symptoms were reported by 73 (65%)
patients, with 52 (46%) patients experiencing these daily.
During the study, 98 (88%) patients experienced a total of
483 attacks, 77% of which required treatment at a health
care facility and/or hemin administration (median [range] annualized attack rate 2.0 [0.0-37.0]). Elevated levels of hepatic
ÎŽ-aminolevulinic acid synthase 1 messenger ribonucleic acid levels, ÎŽ-aminolevulinic acid, and porphobilinogen compared with
the upper limit of normal in healthy individuals were observed
at baseline and increased further during attacks. Patients had
impaired quality of life and increased health care utilization.
CONCLUSIONS: Patients experienced attacks often requiring treatment in a health care facility and/or with hemin, as
well as chronic symptoms that adversely influenced day-to-day
functioning. In this patient group, the high disease burden
and diminished quality of life highlight the need for novel
therapies. (Hepatology 2020;71:1546-1558)
EXPLORE: A prospective, multinational natural history study of patients with acute hepatic porphyria with recurrent attacks
BACKGROUND AND AIMS: Acute hepatic porphyria
comprises a group of rare genetic diseases caused by mutations in genes involved in heme biosynthesis. Patients can
experience acute neurovisceral attacks, debilitating chronic
symptoms, and long-term complications. There is a lack of
multinational, prospective data characterizing the disease and
current treatment practices in severely affected patients.
APPROACH AND RESULTS: EXPLORE is a prospective,
multinational, natural history study characterizing disease activity and clinical management in patients with acute hepatic
porphyria who experience recurrent attacks. Eligible patients
had a confirmed acute hepatic porphyria diagnosis and had
experienced â„3 attacks in the prior 12 months or were receiving prophylactic treatment. A total of 112 patients were enrolled and followed for at least 6 months. In the 12 months
before the study, patients reported a median (range) of 6
(0-52) acute attacks, with 52 (46%) patients receiving hemin
prophylaxis. Chronic symptoms were reported by 73 (65%)
patients, with 52 (46%) patients experiencing these daily.
During the study, 98 (88%) patients experienced a total of
483 attacks, 77% of which required treatment at a health
care facility and/or hemin administration (median [range] annualized attack rate 2.0 [0.0-37.0]). Elevated levels of hepatic
ÎŽ-aminolevulinic acid synthase 1 messenger ribonucleic acid levels, ÎŽ-aminolevulinic acid, and porphobilinogen compared with
the upper limit of normal in healthy individuals were observed
at baseline and increased further during attacks. Patients had
impaired quality of life and increased health care utilization.
CONCLUSIONS: Patients experienced attacks often requiring treatment in a health care facility and/or with hemin, as
well as chronic symptoms that adversely influenced day-to-day
functioning. In this patient group, the high disease burden
and diminished quality of life highlight the need for novel
therapies. (Hepatology 2020;71:1546-1558)
Search for electroweak production of single top quarks in collisions.
We present a search for electroweak production of single top quarks in the electron+jets and muon+jets decay channels. The measurements use ~90 pb^-1 of data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with the DZero detector between 1992 and 1995. We use events that include a tagging muon, implying the presence of a b jet, to set an upper limit at the 95% confidence level on the cross section for the s-channel process ppbar->tb+X of 39 pb. The upper limit for the t-channel process ppbar->tqb+X is 58 pb. (arXiv
Hard Single Diffraction in pbarp Collisions at root-s = 630 and 1800 GeV
Using the D0 detector, we have studied events produced in proton-antiproton
collisions that contain large forward regions with very little energy
deposition (``rapidity gaps'') and concurrent jet production at center-of-mass
energies of root-s = 630 and 1800 Gev. The fractions of forward and central jet
events associated with such rapidity gaps are measured and compared to
predictions from Monte Carlo models. For hard diffractive candidate events, we
use the calorimeter to extract the fractional momentum loss of the scattered
protons.Comment: 11 pages 4 figures. submitted to PR
The formation and fate of internal waves in the South China Sea
Internal gravity waves, the subsurface analogue of the familiar surface gravity waves that break on beaches, are ubiquitous in the ocean. Because of their strong vertical and horizontal currents, and the turbulent mixing caused by their breaking, they affect a panoply of ocean processes, such as the supply of nutrients for photosynthesis1, sediment and pollutant transport2 and acoustic transmission3; they also pose hazards for man-made structures in the ocean4. Generated primarily by the wind and the tides, internal waves can travel thousands of kilometres from their sources before breaking5, making it challenging to observe them and to include them in numerical climate models, which are sensitive to their effects6,7. For over a decade, studies8-11 have targeted the South China Sea, where the oceans' most powerful known internal waves are generated in the Luzon Strait and steepen dramatically as they propagate west. Confusion has persisted regarding their mechanism of generation, variability and energy budget, however, owing to the lack of in situ data from the Luzon Strait, where extreme flow conditions make measurements difficult. Here we use new observations and numerical models to (1) show that the waves begin as sinusoidal disturbances rather than arising from sharp hydraulic phenomena, (2) reveal the existence of >200-metre-high breaking internal waves in the region of generation that give rise to turbulence levels >10,000 times that in the open ocean, (3) determine that the Kuroshio western boundary current noticeably refracts the internal wave field emanating from the Luzon Strait, and (4) demonstrate a factor-of-two agreement between modelled and observed energy fluxes, which allows us to produce an observationally supported energy budget of the region. Together, these findings give a cradle-to-grave picture of internal waves on a basin scale, which will support further improvements of their representation in numerical climate predictions
Measurement of the Top Quark Mass in the Dilepton Channel
We report a measurement of the top quark mass using six candidate events for
the process pbarp->ttbar->l^+ nu l^- nubar b bbar + X, observed in the D0
experiment at the Fermilab ppbar collider. Using maximum likelihood fits to the
dynamics of the decays, we measure a mass for the top quark of m(top) = 168.4
+- 12.3 (stat) +- 3.6 (syst) GeV/c^2. We combine this result with our previous
measurement in the ttbar->l+jets channel to obtain m(top) = 172.1 +- 7.1
GeV/c^2 as the best value of the mass of the top quark measured by D0.Comment: 48 pages, 22 figures (encapsultaed postscript), Submitted for
publication in Physical Review
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