6,534 research outputs found
Performance of Laying Hens Fed Increasing Amounts of Lysine in Low Protein Diets
The current N.R.C. (1977) recommendations for lysine content of laying hen rations is 0.60%. This level of lysine is recommended along with 15% protein. The influence of protein level or protein quality on this requirement is not known. This experiment examined laying hen performance over a range (0.55% to 0.80%) of lysine levels in 10% and 12% protein diets to determine optimum lysine intake. Also, the influence of the addition of the amino acids isoleucine and tryptophan to the 10% protein diet was studied
Strain Differential in Amino Acid Requirements for Laying Hens
This study involved the effects of amino acid supplementation of a low protein layer diet on egg production of two strains of chickens
Is the Cepheus E Outflow driven by a Class 0 Protostar?
New early release observations of the Cepheus E outflow and its embedded
source, obtained with the Spitzer Space Telescope, are presented. We show the
driving source is detected in all 4 IRAC bands, which suggests that traditional
Class 0 classification, although essentially correct, needs to accommodate the
new high sensitivity infrared arrays and their ability to detected deeply
embedded sources. The IRAC, MIPS 24 and 70 microns new photometric points are
consistent with a spectral energy distribution dominated by a cold, dense
envelope surrounding the protostar. The Cep E outflow, unlike its more famous
cousin the HH 46/47 outflow, displays a very similar morphology in the near and
mid-infrared wavelengths, and is detected at 24 microns. The interface between
the dense molecular gas (where Cep E lies) and less dense interstellar medium,
is well traced by the emission at 8 and 24 microns, and is one of the most
exotic features of the new IRAC and MIPS images. IRS observations of the North
lobe of the flow confirm that most of the emission is due to the excitation of
pure H2 rotational transitions arising from a relatively cold (Tex~700 K) and
dense (N{H}~9.6E20 cm-2 molecular gas.Comment: 14 pages (pre-print format), including 6 figures. Published in ApJ
Special Spitzer Issue (2004
Survey of Terrestrial Invertebrate Species from Byers Cave; Dade County, Georgia
Byers Cave is one of Georgia’s largest cave systems and is inhabited by a wide variety of unique invertebrate organisms that have not been documented or studied. From March 2008 through April 2010, baited ramp pit-fall traps and visual surveys were used to sample and document invertebrate species that live in this cave system. After three trapping periods and four visual surveys, we collected over 4,400 individuals comprising 13 orders, 29 families and 34 species. The majority of these species were troglophiles and trogloxenes; however, there were also numerous troglobitic species present
Water Quality Impacts of Naturals Riparian Grasses Part 2: Modeling Effects of Channelization on Sediment Trapping
A methodology is developed to determine expected sediment trapping in riparian vegetative filter strips considering channelization of flow. The framework consists of defining the channel network stochastically, with deposition/detachment in each channel being modeled deterministically. The two approaches were then combined to develop a model which could predict expected trapping efficiencies for vegetative filters under known field conditions. The model was then extended to include conditions such as rainfall on the filter so as to make it applicable to generic field situations.
Field and laboratory studies were conducted to collect and estimate data to develop and evaluate the model. sediment concentrations were measured for natural vegetative filters located on a slope of 8.7%, subjected to inflows from upslope bare soil plots. Surface elevations were measured for the filter. Flow networks and channel shapes were defined by applying the digital elevation model to the micro-relief data. Actual distributions and standard fitted distributions for channel flows and channel shapes were developed.
Model evaluation was done for selected values of Manning\u27s n to give predicted filter trapping efficiencies within 2% of the observed, indicating model validity. Sensitivity analysis was conducted using the general model and the fitted probability distributions
Soil quality after eight years under high tunnels
The sustainability of soil quality under high tunnels will influence management of high tunnels currently in use and grower decisions regarding design and management of new high tunnels to be constructed. Soil quality was quantified using measures of soil
pH, salinity, total carbon, and particulate organic matter (POM) carbon in a silt loam soil that had been in vegetable production under high tunnels at the research station in Olathe, KS, for eight years. Soil under high tunnels was compared with that in adjacent fields in both a conventional and an organic management system. The eight-year presence of high tunnels under the conventional management system resulted in increased soil pH and salinity but did not affect soil carbon. In the organic management
system, high tunnels did not affect soil pH, increased soil salinity, and influenced soil
carbon (C) pools with an increase in POM carbon. The increases in soil salinity were not enough to be detrimental to crops. These results indicate that soil quality was not adversely affected by eight years under stationary high tunnels managed with conventionally or organically produced vegetable crops
OvMark: a user-friendly system for the identification of prognostic biomarkers in publically available ovarian cancer gene expression datasets
Background: Ovarian cancer has the lowest survival rate of all gynaecologic cancers and is characterised by a lack of early symptoms and frequent late stage diagnosis. There is a paucity of robust molecular markers that are independent of and complementary to clinical parameters such as disease stage and tumour grade.
METHODS: We have developed a user-friendly, web-based system to evaluate the association of genes/miRNAs with outcome in ovarian cancer. The OvMark algorithm combines data from multiple microarray platforms (including probesets targeting miRNAs) and correlates them with clinical parameters (e.g. tumour grade, stage) and outcomes (disease free survival (DFS), overall survival). In total, OvMark combines 14 datasets from 7 different array platforms measuring the expression of ~17,000 genes and 341 miRNAs across 2,129 ovarian cancer samples.
RESULTS: To demonstrate the utility of the system we confirmed the prognostic ability of 14 genes and 2 miRNAs known to play a role in ovarian cancer. Of these genes, CXCL12 was the most significant predictor of DFS (HR = 1.42, p-value = 2.42x10-6). Surprisingly, those genes found to have the greatest correlation with outcome have not been heavily studied in ovarian cancer, or in some cases in any cancer. For instance, the three genes with the greatest association with survival are SNAI3, VWA3A and DNAH12.
CONCLUSIONS/IMPACT:
OvMark is a powerful tool for examining putative gene/miRNA prognostic biomarkers in ovarian cancer (available at http://glados.ucd.ie/OvMark/index.html). The impact of this tool will be in the preliminary assessment of putative biomarkers in ovarian cancer, particularly for research groups with limited bioinformatics facilities
Studies of superconducting materials with muon spin rotation
The muon spin rotation/relaxation technique was found to be an exceptionally effective means of measuring the magnetic properties of superconductors, including the new high temperature superconductor materials, at the microscopic level. The technique directly measures the magnetic penetration depth (type II superconductors (SC's)) and detects the presence of magnetic ordering (antiferromagnetism or spin-glass ordering were observed in some high temperature superconductor (HTSC's) and in many closely related compounds). Extensive studies of HTSC materials were conducted by the Virginia State University - College of William and Mary - Columbia University collaboration at Brookhaven National Laboratory and TRIUMF (Vancouver). A survey of LaSrCuO and YBaCaCuO systems shows an essentially linear relationship between the transition temperature T(sub c) and the relaxation rate. This appears to be a manifestation of the proportionality between T(sub c) and the Fermi energy, which suggests a high energy scale for the SC coupling, and which is not consistent with the weak coupling of phonon-mediated SC. Studies of LaCuO and YBaCuO parent compounds show clear evidence of antiferromagnetism. YBa2Cu(3-x)CO(x)O7 shows the simultaneous presence of spin-glass magnetic ordering and superconductivity. Three-dimensional SC, (Ba, K) BiO3, unlike the layered CuO-based compounds, shows no suggestion of magnetic ordering. Experimental techniques and theoretical implications are discussed
APOLLO: the Apache Point Observatory Lunar Laser-ranging Operation: Instrument Description and First Detections
A next-generation lunar laser ranging apparatus using the 3.5 m telescope at
the Apache Point Observatory in southern New Mexico has begun science
operation. APOLLO (the Apache Point Observatory Lunar Laser-ranging Operation)
has achieved one-millimeter range precision to the moon which should lead to
approximately one-order-of-magnitude improvements in the precision of several
tests of fundamental properties of gravity. We briefly motivate the scientific
goals, and then give a detailed discussion of the APOLLO instrumentation.Comment: 37 pages; 10 figures; 1 table: accepted for publication in PAS
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