1,155 research outputs found
Differences in intestinal size, structure, and function contributing to feed efficiency in broiler chickens reared at geographically distant locations
The contribution of the intestinal tract to differences in residual feed intake (RFI) has been inconclusively studied in chickens so far. It is also not clear if RFI-related differences in intestinal function are similar in chickens raised in different environments. The objective was to investigate differences in nutrient retention, visceral organ size, intestinal morphology, jejunal permeability and expression of genes related to barrier function, and innate immune response in chickens of diverging RFI raised at 2 locations (L1: Austria; L2: UK). The experimental protocol was similar, and the same dietary formulation was fed at the 2 locations. Individual BW and feed intake (FI) of chickens (Cobb 500FF) were recorded from d 7 of life. At 5 wk of life, chickens (L1, n = 157; L2 = 192) were ranked according to their RFI, and low, medium, and high RFI chickens were selected (n = 9/RFI group, sex, and location). RFI values were similar between locations within the same RFI group and increased by 446 and 464 g from low to high RFI in females and males, respectively. Location, but not RFI rank, affected growth, nutrient retention, size of the intestine, and jejunal disaccharidase activity. Chickens from L2 had lower total body weight gain and mucosal enzyme activity but higher nutrient retention and longer intestines than chickens at L1. Parameters determined only at L1 showed increased crypt depth in the duodenum and jejunum and enhanced paracellular permeability in low vs. high RFI females. Jejunal expression of IL1B was lower in low vs. high RFI females at L2, whereas that of TLR4 at L1 and MCT1 at both locations was higher in low vs. high RFI males. Correlation analysis between intestinal parameters and feed efficiency metrics indicated that feed conversion ratio was more correlated to intestinal size and function than was RFI. In conclusion, the rearing environment greatly affected intestinal size and function, thereby contributing to the variation in chicken RFI observed across locations
Electronic signature of the vacancy ordering in NbO (Nb3O3)
We investigated the electronic structure of the vacancy-ordered 4d-transition
metal monoxide NbO (Nb3O3) using angle-integrated soft- and hard-x-ray
photoelectron spectroscopy as well as ultra-violet angle-resolved photoelectron
spectroscopy. We found that density-functional-based band structure
calculations can describe the spectral features accurately provided that
self-interaction effects are taken into account. In the angle-resolved spectra
we were able to identify the so-called vacancy band that characterizes the
ordering of the vacancies. This together with the band structure results
indicates the important role of the very large inter-Nb-4d hybridization for
the formation of the ordered vacancies and the high thermal stability of the
ordered structure of niobium monoxide
Gravitational Properties of Monopole Spacetimes Near the Black Hole Threshold
Although nonsingular spacetimes and those containing black holes are
qualitatively quite different, there are continuous families of configurations
that connect the two. In this paper we use self-gravitating monopole solutions
as tools for investigating the transition between these two types of
spacetimes. We show how causally distinct regions emerge as the black hole
limit is achieved, even though the measurements made by an external observer
vary continuously. We find that near-critical solutions have a naturally
defined entropy, despite the absence of a true horizon, and that this has a
clear connection with the Hawking-Bekenstein entropy. We find that certain
classes of near-critical solutions display naked black hole behavior, although
they are not truly black holes at all. Finally, we present a numerical
simulation illustrating how an incident pulse of matter can induce the
dynamical collapse of a monopole into an extremal black hole. We discuss the
implications of this process for the third law of black hole thermodynamics.Comment: 23 pages, 4 figures RevTe
Operational generation of AVHRR-based cloud products for Europe and the Arctic at EUMETSAT's Satellite Application Facility on Climate Monitoring (CM-SAF)
The Satelite Application Facility on Climate Monitoring has implemented a new processing environment for AVHRR-based climate monitoring products. AVHRR measurements from NOAA-17, NOAA-18 and MetOp-A are utilized to generate daily and monthly means of several cloud parameters for Europe and the Inner Arctic: Cloud fraction, cloud types, cloud phase, cloud top height, cloud optical thickness and cloud liquid water path
Epitaxial and layer-by-layer growth of EuO thin films on yttria-stabilized cubic zirconia (001) using MBE distillation
We have succeeded in growing epitaxial and highly stoichiometric films of EuO
on yttria-stabilized cubic zirconia (YSZ) (001). The use of the Eu-distillation
process during the molecular beam epitaxy assisted growth enables the
consistent achievement of stoichiometry. We have also succeeded in growing the
films in a layer-by-layer fashion by fine tuning the Eu vs. oxygen deposition
rates. The initial stages of growth involve the limited supply of oxygen from
the YSZ substrate, but the EuO stoichiometry can still be well maintained. The
films grown were sufficiently smooth so that the capping with a thin layer of
aluminum was leak tight and enabled ex situ experiments free from trivalent Eu
species. The findings were used to obtain recipes for better epitaxial growth
of EuO on MgO (001).Comment: 10 pages, 15 figure
NMDAR1 autoantibodies amplify behavioral phenotypes of genetic white matter inflammation: a mild encephalitis model with neuropsychiatric relevance
Encephalitis has an estimated prevalence of â€0.01%. Even with extensive diagnostic work-up, an infectious etiology is identified or suspected in <50% of cases, suggesting a role for etiologically unclear, noninfectious processes. Mild encephalitis runs frequently unnoticed, despite slight neuroinflammation detectable postmortem in many neuropsychiatric illnesses. A widely unexplored field in humans, though clearly documented in rodents, is genetic brain inflammation, particularly that associated with myelin abnormalities, inducing primary white matter encephalitis. We hypothesized that âautoimmune encephalitidesâ may result from any brain inflammation concurring with the presence of brain antigen-directed autoantibodies, e.g., against N-methyl-D-aspartate-receptor NR1 (NMDAR1-AB), which are not causal of, but may considerably shape the encephalitis phenotype. We therefore immunized young female Cnpâ/â mice lacking the structural myelin protein 2âČ-3âČ-cyclic nucleotide 3âČ-phosphodiesterase (Cnp) with a âcocktailâ of NMDAR1 peptides. Cnpâ/â mice exhibit early low-grade inflammation of white matter tracts and bloodâbrain barrier disruption. Our novel mental-time-travel test disclosed that Cnpâ/â mice are compromised in whatâwhereâwhen orientation, but this episodic memory readout was not further deteriorated by NMDAR1-AB. In contrast, comparing wild-type and Cnpâ/â mice without/with NMDAR1-AB regarding hippocampal learning/memory and motor balance/coordination revealed distinct stair patterns of behavioral pathology. To elucidate a potential contribution of oligodendroglial NMDAR downregulation to NMDAR1-AB effects, we generated conditional NR1 knockout mice. These mice displayed normal Morris water maze and mental-time-travel, but beam balance performance was similar to immunized Cnpâ/â. Immunohistochemistry confirmed neuroinflammation/neurodegeneration in Cnpâ/â mice, yet without add-on effect of NMDAR1-AB. To conclude, genetic brain inflammation may explain an encephalitic component underlying autoimmune conditions
High rates of clinically relevant incidental findings by total-body CT scanning in trauma patients; results of the REACT-2 trial
To determine whether there is a difference in frequency and clinical relevance of incidental findings detected by total-body computed tomography scanning (TBCT) compared to those by the standard work-up (STWU) with selective computed tomography (CT) scanning. Trauma patients from five trauma centres were randomized between April 2011 and January 2014 to TBCT imaging or STWU consisting of conventional imaging with selective CT scanning. Incidental findings were divided into three categories: 1) major finding, may cause mortality; 2) moderate finding, may cause morbidity; and 3) minor finding, hardly relevant. Generalized estimating equations were applied to assess differences in incidental findings. In total, 1083 patients were enrolled, of which 541 patients (49.9 %) were randomized for TBCT and 542 patients (50.1 %) for STWU. Major findings were detected in 23 patients (4.3 %) in the TBCT group compared to 9 patients (1.7 %) in the STWU group (adjusted rate ratio 2.851; 95%CI 1.337-6.077; p <0.007). Findings of moderate relevance were detected in 120 patients (22.2 %) in the TBCT group compared to 86 patients (15.9 %) in the STWU group (adjusted rate ratio 1.421; 95%CI 1.088-1.854; p <0.010). Compared to selective CT scanning, more patients with clinically relevant incidental findings can be expected by TBCT scanning. aEuro cent Total-body CT scanning in trauma results in 1.5 times more incidental findings. aEuro cent Evaluation by TBCT in trauma results in more patients with incidental findings. aEuro cent In every category of clinical relevance, TBCT detects more incidental findings
Cost-effectiveness of immediate total-body CT in patients with severe trauma (REACT-2 trial)
Background: The effect of immediate total-body CT (iTBCT) on health economic aspects in patients with severe trauma is an underreported issue. This study determined the cost-effectiveness of iTBCT compared with conventional radiological imaging with selective CT (standard work-up (STWU)) during the initial trauma evaluation. Methods: In this multicentre RCT, adult patients with a high suspicion of severe injury were randomized in-hospital to iTBCT or STWU. Hospital healthcare costs were determined for the first 6 months after the injury. The probability of iTBCT being cost-effective was calculated for various levels of willingness-to-pay per extra patient alive. Results: A total of 928 Dutch patients with complete clinical follow-up were included. Mean costs of hospital care were (sic)25 809 (95 per cent bias-corrected and accelerated (bca) c.i. (sic)22 617 to (sic)29 137) for the iTBCT group and (sic)26 155 ((sic)23 050 to (sic)29 344) for the STWU group, a difference per patient in favour of iTBCT of (sic)346 ((sic)4987 to (sic)4328) (P = 0.876). Proportions of patients alive at 6 months were not different. The proportion of patients alive without serious morbidity was 61.6 per cent in the iTBCT group versus 66.7 per cent in the STWU group (difference -5.1 per cent; P = 0.104). The probability of iTBCT being cost-effective in keeping patients alive remained below 0.56 for the whole group, but was higher in patients with multiple trauma (0.8-0.9) and in those with traumatic brain injury (more than 0.9). Conclusion: Economically, from a hospital healthcare provider perspective, iTBCT should be the diagnostic strategy of first choice in patients with multiple trauma or traumatic brain injury
Differences in intestinal size, structure, and function contributing to feed efficiency in broiler chickens reared at geographically distant locations
peer-reviewedThe contribution of the intestinal tract to differences in residual feed intake (RFI) has been inconclusively studied in chickens so far. It is also not clear if RFI-related differences in intestinal function are similar in chickens raised in different environments. The objective was to investigate differences in nutrient retention, visceral organ size, intestinal morphology, jejunal permeability and expression of genes related to barrier function, and innate immune response in chickens of diverging RFI raised at 2 locations (L1: Austria; L2: UK). The experimental protocol was similar, and the same dietary formulation was fed at the 2 locations. Individual BW and feed intake (FI) of chickens (Cobb 500FF) were recorded from d 7 of life. At 5 wk of life, chickens (L1, n = 157; L2 = 192) were ranked according to their RFI, and low, medium, and high RFI chickens were selected (n = 9/RFI group, sex, and location). RFI values were similar between locations within the same RFI group and increased by 446 and 464 g from low to high RFI in females and males, respectively. Location, but not RFI rank, affected growth, nutrient retention, size of the intestine, and jejunal disaccharidase activity. Chickens from L2 had lower total body weight gain and mucosal enzyme activity but higher nutrient retention and longer intestines than chickens at L1. Parameters determined only at L1 showed increased crypt depth in the duodenum and jejunum and enhanced paracellular permeability in low vs. high RFI females. Jejunal expression of IL1B was lower in low vs. high RFI females at L2, whereas that of TLR4 at L1 and MCT1 at both locations was higher in low vs. high RFI males. Correlation analysis between intestinal parameters and feed efficiency metrics indicated that feed conversion ratio was more correlated to intestinal size and function than was RFI. In conclusion, the rearing environment greatly affected intestinal size and function, thereby contributing to the variation in chicken RFI observed across locations
Discrete structures in gravity
Discrete approaches to gravity, both classical and quantum, are reviewed
briefly, with emphasis on the method using piecewise-linear spaces. Models of
3-dimensional quantum gravity involving 6j-symbols are then described, and
progress in generalising these models to four dimensions is discussed, as is
the relationship of these models in both three and four dimensions to
topological theories. Finally, the repercussions of the generalisations are
explored for the original formulation of discrete gravity using edge-length
variables.Comment: 30 pages, 4 figure
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