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Influence of Wheat Straw Pelletizing and Inclusion Rate in Dry Rolled or Steam-flaked Corn-based Finishing Diets on Characteristics of Digestion for Feedlot Cattle.
Eight Holstein steers (216±48 kg body weight) fitted with ruminal and duodenal cannulas were used to evaluate effects of wheat straw processing (ground vs pelleted) at two straw inclusion rates (7% and 14%; dry matter basis) in dry rolled or steam-flaked corn-based finishing diets on characteristics of digestion. The experimental design was a split plot consisting of two simultaneous 4×4 Latin squares. Increasing straw level reduced ruminal (p<0.01) and total tract (p = 0.03) organic matter (OM) digestion. As expected, increasing wheat straw level from 7% to 14% decreased (p<0.05) ruminal and total tract digestion of OM. Digestion of neutral detergent fiber (NDF) and starch, per se, were not affected (p>0.10) by wheat straw level. Likewise, straw level did not influence ruminal acetate and propionate molar proportions or estimated methane production (p>0.10). Pelleting straw did not affect (p≥0.48) ruminal digestion of OM, NDF, and starch, or microbial efficiency. Ruminal feed N digestion was greater (7.4%; p = 0.02) for ground than for pelleted wheat straw diets. Although ruminal starch digestion was not affected by straw processing, post-ruminal (p<0.01), and total-tract starch (p = 0.05) digestion were greater for ground than for pelleted wheat straw diets, resulting in a tendency for increased post-ruminal (p = 0.06) and total tract (p = 0.07) OM digestion. Pelleting wheat straw decreased (p<0.01) ruminal pH, although ruminal volatile fatty acids (VFA) concentration and estimated methane were not affected (p≥0.27). Ruminal digestion of OM and starch, and post-ruminal and total tract digestion of OM, starch and N were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal NDF digestion was greater (p = 0.02) for dry rolled than for steam-flaked corn, although total tract NDF digestion was unaffected (p = 0.94). Ruminal microbial efficiency and ruminal degradation of feed N were not affected (p>0.14) by corn processing. However, microbial N flow to the small intestine and ruminal N efficiency (non-ammonia N flow to the small intestine/N intake) were greater (p<0.01) for steam-flaked than for dry rolled corn-based diets. Ruminal pH and total VFA concentration were not affected (p≥ 0.16) by corn processing method. Compared with dry rolled corn, steam-flaked corn-based diets resulted in decreased acetate:propionate molar ratio (p = 0.02). It is concluded that at 7% or 14% straw inclusion rate, changes in physical characteristics of wheat straw brought about by pelleting negatively impact OM digestion of both steam-flaked and dry-rolled corn-based finishing diets. This effect is due to decreased post-ruminal starch digestion. Replacement of ground straw with pelleted straw also may decrease ruminal pH
The Unusual Spectral Energy Distribution of a Galaxy Previously Reported to be at Redshift 6.68
Observations of distant galaxies are important both for understanding how
galaxies form and for probing the physical conditions of the universe at the
earliest epochs. It is, however, extremely difficult to identify galaxies at
redshift z>5, because these galaxies are faint and exhibit few spectral
features. In a previous work, we presented observations that supported the
identification of a galaxy at redshift z = 6.68 in a deep STIS field. Here we
present new ground-based photometry of the galaxy. We find that the galaxy
exhibits moderate detections of flux in the optical B and V images that are
inconsistent with the expected absence of flux at wavelength shortward of the
redshifted Lyman-alpha emission line of a galaxy at redshift z>5. In addition,
the new broad-band imaging data not only show flux measurements of this galaxy
that are incompatible with the previous STIS measurement, but also suggest a
peculiar spectral energy distribution that cannot be fit with any galaxy
spectral template at any redshift. We therefore conclude that the redshift
identification of this galaxy remains undetermined.Comment: 9 pages, 2 figures; To appear in Nature (30 November 2000
Evidence of Andreev bound states as a hallmark of the FFLO phase in -(BEDT-TTF)Cu(NCS)
Superconductivity is a quantum phenomena arising, in its simplest form, from
pairing of fermions with opposite spin into a state with zero net momentum.
Whether superconductivity can occur in fermionic systems with unequal number of
two species distinguished by spin, atomic hyperfine states, flavor, presents an
important open question in condensed matter, cold atoms, and quantum
chromodynamics, physics. In the former case the imbalance between spin-up and
spin-down electrons forming the Cooper pairs is indyced by the magnetic field.
Nearly fifty years ago Fulde, Ferrell, Larkin and Ovchinnikov (FFLO) proposed
that such imbalanced system can lead to exotic superconductivity in which pairs
acquire finite momentum. The finite pair momentum leads to spatially
inhomogeneous state consisting of of a periodic alternation of "normal" and
"superconducting" regions. Here, we report nuclear magnetic resonance (NMR)
measurements providing microscopic evidence for the existence of this new
superconducting state through the observation of spin-polarized quasiparticles
forming so-called Andreev bound states.Comment: 6 pages, 5 fig
Performance of the 2007 WHO Algorithm to diagnose Smear-negative Pulmonary Tuberculosis in a HIV prevalent setting
The 2007 WHO algorithm for diagnosis of smear-negative pulmonary tuberculosis (PTB) including Mycobacterium tuberculosis (MTB) culture was evaluated in a HIV prevalent area of Kenya
The chemokine receptor CCR8 is preferentially expressed in Th2 but not Th1 cells
In this paper we report on the cloning and characterization of mouse CCR8. Like its human homologue, it is predominantly expressed in the thymus. In the periphery, murine CCR8 mRNA was found most abundantly expressed in activated Th2-polarized cells and in NK1.1+ CD4+ T cells. Human CCR8 is also preferentially expressed in human Th2-polarized cells and clones. This pattern of expression suggests that CCR8 is part of a Th2-specific gene expression program. The CCR8 ligands I-309 and its mouse homologue T cell activation gene 3 (TCA-3) are potent chemoattractants for Th2-polarized cells. Taken together, these observations strongly suggest that CCR8 plays a role in the control of Th2 responses, and may represent a potential target for treatment of allergic diseases
Towards the spectral mapping of plastic debris on beaches
Floating and washed ashore marine plastic debris (MPD) is a growing environmental challenge. It has become evident that secluded locations including the Arctic, Antarctic, and remote islands are being impacted by plastic pollution generated thousands of kilometers away. Optical remote sensing of MPD is an emerging field that can aid in monitoring remote environments where in-person observation and data collection is not always feasible. Here we evaluate MPD spectral features in the visible to shortwave infrared regions for detecting varying quantities of MPD that have accumulated on beaches using a spectroradiometer. Measurements were taken from a range of in situ MPD accumulations ranging from 0.08% to 7.94% surface coverage. Our results suggest that spectral absorption features at 1215 nm and 1732 nm are useful for detecting varying abundance levels of MPD in a complex natural environment, however other absorption features at 931 nm, 1045 nm and 2046 nm could not detect in situ MPD. The reflectance of some in situ MPD accumulations was statistically different from samples that only contained organic debris and sand between 1.56% and 7.94% surface cover; however other samples with similar surface cover did not have reflectance that was statistically different from samples containing no MPD. Despite MPD being detectable against a background of sand and organic beach debris, a clear relationship between the surface cover of MPD and the strength of key absorption features could not be established. Additional research is needed to advance our understanding of the factors, such as type of MPD assemblage, that contribute to the bulk reflectance of MPD contaminated landscapes
Perinatal Exposure to Environmentally Relevant Levels of Bisphenol A Decreases Fertility and Fecundity in CD-1 Mice
Bac k g r o u n d: Perinatal exposure to low-doses of bisphenol A (BPA) results in alterations in the ovary, uterus, and mammary glands and in a sexually dimorphic region of the brain known to be important for estrous cyclicity. Objectives: We aimed to determine whether perinatal exposure to environmentally relevant doses of BPA alters reproductive capacity. Met h o d s: Female CD-1 mice that were exposed to BPA at 0, 25 ng, 250 ng, or 25 µg/kg body weight (BW)/day or diethylstilbestrol (DES) at 10 ng/kg BW/day (positive control) from gestational day 8 through day 16 of lactation were continuously housed with proven breeder males for 32 weeks starting at 2 months of age. At each delivery, pups born to these mating pairs were removed. The cumulative number of pups, number of deliveries, and litter size were recorded. The purity of the BPA used in this and our previous studies was assessed using HPLC, mass spectrometry, and nuclear magnetic resonance. Res u l t s: The forced breeding experiment revealed a decrease in the cumulative number of pups, observed as a nonmonotonic dose–response effect, and a decline in fertility and fecundity over time in female mice exposed perinatally to BPA. The BPA was 97 % pure, with no evidence of contaminatio
MRCP compared to diagnostic ERCP for diagnosis when biliary obstruction is suspected: a systematic review
BACKGROUND: Magnetic resonance cholangiopancreatography (MRCP) is an alternative to diagnostic endoscopic retrograde cholangiopancreatography (ERCP) for investigating biliary obstruction. The use of MRCP, a non-invasive procedure, may prevent the use of unnecessary invasive procedures. The aim of the study was to compare the findings of MRCP with those of ERCP by the computation of accuracy statistics. METHODS: Thirteen electronic bibliographic databases, covering biomedical, science, health economics and grey literature were searched. A systematic review of studies comparing MRCP to diagnostic ERCP in patients with suspected biliary obstruction was conducted. Sensitivity, specificity, likelihood ratios, acceptability and adverse events were reported. RESULTS: 25 studies were identified reporting several conditions including choledocholithiasis (18 studies), malignancy (four studies), obstruction (three studies), stricture (two studies) and dilatation (five studies). Three of the 18 studies reporting choledocholithiasis were excluded from the analysis due to lack of data, or differences in study design. The sensitivity for the 15 studies of choledocholithiasis ranged from 0.50 to 1.00 while specificity ranged from 0.83 to 1.00. The positive likelihood ratio ranged: from 5.44–47.72 and the negative likelihood ratio for the 15 studies ranged from 0.00–0.51. Significant heterogeneity was found across the 15 studies so the sensitivities and specificities were summarised by a Receiver Operating Characteristic (ROC) curve. For malignancy, sensitivity ranged from 0.81 to 0.94 and specificity from 0.92 to 1.00. Positive likelihood ratios ranged from 10.12 to 43 and negative likelihood ratios ranged from 0.15 to 0.21, although these estimates were less reliable. CONCLUSION: MRCP is a comparable diagnostic investigation in comparison to ERCP for diagnosing biliary obstruction
Wilson Expansion of QCD Propagators at Three Loops: Operators of Dimension Two and Three
In this paper we construct the Wilson short distance operator product
expansion for the gluon, quark and ghost propagators in QCD, including
operators of dimension two and three, namely, A^2, m^2, m A^2, \ovl{\psi} \psi
and m^3. We compute analytically the coefficient functions of these operators
at three loops for all three propagators in the general covariant gauge. Our
results, taken in the Landau gauge, should help to improve the accuracy of
extracting the vacuum expectation values of these operators from lattice
simulation of the QCD propagators.Comment: 20 pages, no figure
Exploring the theories, determinants and policy-options of street vending: a demand-side approach
Street vending has been a common feature of urban centres for several decades, with a relatively high proportion of developing countries’ populations depending on it for employment, income or survival. Taking a supply-side approach, studies have shown that urban planners’ responses to street vending have followed the modernism theory. In this paper, we take a demand-side (buyer-focused) approach to studying street vending, which to date has received little attention from the academic community. Employing data from Lagos state, Nigeria, we report four explanations underpinning the demand-side of street vending: formal economy failures, social/redistributive, financial gains, and multifeature. These are, in turn, explained by individuals’ marital status, level of education, and perception. Our findings highlight the need for urban planners to embrace pragmatic policies in addressing these demand-side drivers of street vending and use of urban space, rather than criminalising its actors
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