1,589 research outputs found
Genesee River Watershed Project. Water Quality Analysis of the Oatka Creek Watershed. Volume 6. Nutrient Concentration and Loading, Identification of Point and Nonpoint Sources of Pollution, Total Maximum Daily Load, and an Assessment of Management Practices using the Soil Water Assessment Tool (SWAT) Model. A report to the USDA.
Oatka Creek is the second largest tributary of the Genesee River and is a highly prized trout fishery. The Oatka Creek portion of the Genesee River Project Study focused on identifying nonpoint and point sources, locating and quantifying the nutrient and sediment losses from Oatka Creek watershed, and through simulation identifying possible remediation or management practices. To accomplish this task, a multifaceted, integrated approach was taken by combining stream monitoring, segment analysis, and hydrologic modeling [Soil and Water Assessment Tool (SWAT)]. Runoff from nonpoint sources (Confined Animal Feeding Operation sites, agricultural practices, and urban areas) and point sources (wastewater treatment plants and State Pollution Discharge Elimination Sites), all anthropogenic sources, accounts for ~70% of the phosphorus load of Oatka Creek, suggesting improvements in stream water quality are possible. The most effective management recommendation to reduce the overall total phosphorus loading in Oatka Creek is to upgrade all four wastewater treatment plants (Warsaw, Pavilion, Leroy, and Scottsville) to tertiary treatment systems. Other effective management recommendations focused on nonpoint sources such as grassed waterways, buffer strips, and cover crops within the two most impaired tributaries (Wyoming Road and Roanoke Road) in the Oatka Creek watershed. Either or both practices together would significantly improve the water quality in the Oatka Creek watershed by reducing the average annual P concentration to below the 45-μg P/L target. Portions of the creek are experiencing stream bank soil erosion. Stream bank stabilization techniques, some already implemented, would have a beneficial impact on reducing the total phosphorus and total suspended solids loading in this segment of Oatka Creek
Portable Unit for Metabolic Analysis
The Portable Unit for Metabolic Analysis (PUMA) is an instrument that measures several quantities indicative of human metabolic function. Specifically, this instrument makes time-resolved measurements of temperature, pressure, flow, and the partial pressures of oxygen and carbon dioxide in breath during both inhalation and exhalation. Portable instruments for measuring these quantities have been commercially available, but the response times of those instruments are too long to enable temporal resolution of phenomena on the time scales of human respiration cycles. In contrast, the response time of the PUMA is significantly shorter than characteristic times of human respiration phenomena, making it possible to analyze varying metabolic parameters, not only on sequential breath cycles but also at successive phases of inhalation and exhalation within the same breath cycle. In operation, the PUMA is positioned to sample breath near the subject s mouth. Commercial off-the-shelf sensors are used for three of the measurements: a miniature pressure transducer for pressure, a thermistor for temperature, and an ultrasonic sensor for flow. Sensors developed at Glenn Research Center are used for measuring the partial pressures of oxygen and carbon dioxide: The carbon dioxide sensor exploits the relatively strong absorption of infrared light by carbon dioxide. Light from an infrared source passes through the stream of inhaled or exhaled gas and is focused on an infrared- sensitive photodetector. The oxygen sensor exploits the effect of oxygen in quenching the fluorescence of ruthenium-doped organic molecules in a dye on the tip of an optical fiber. A blue laser diode is used to excite the fluorescence, and the optical fiber carries the fluorescent light to a photodiode, the temporal variation of the output of which bears a known relationship with the rate of quenching of fluorescence and, hence, with the partial pressure of oxygen. The outputs of the sensors are digitized, preprocessed by a small onboard computer, and then sent wirelessly to a desktop computer, where the collected data are analyzed and displayed. In addition to the raw data on temperature, pressure, flow, and mole fractions of oxygen and carbon dioxide, the display can include volumetric oxygen consumption, volumetric carbon dioxide production, respiratory equivalent ratio, and volumetric flow rate of exhaled gas
Portable Unit for Metabolic Analysis
The Portable Unit for Metabolic Analysis measures human metabolic function. The compact invention attaches to the face of a subject and it is able to record highly time-resolved measurements of air temperature and pressure, flow rates during inhalation and exhalation, and oxygen and carbon dioxide partial pressure. The device is capable of `breath-by-breath` analysis and `within-breath` analysis at high temporal resolution
HI Observations of Giant Low Surface Brightness Galaxies
We have used the Nancay Radio Telescope to obtain new global HI data for 16
giant low surface brightness (LSB) galaxies. Our targets have optical
luminosities and disk scale lengths at the high end for spiral galaxies
(L_B~10^10 Lsun and h_r>~6 kpc for H_0=75 km/s/Mpc), but they have diffuse
stellar disks, with mean disk surface brightnesses ~1 magnitude or more fainter
than normal giant spirals. Thirteen of the galaxies previously had been
detected in HI by other workers, but the published HI observations were either
confused, resolved by the telescope beam, of low signal-to-noise, or showed
significant discrepancies between different authors. For the other 3 galaxies,
no HI data were previously available. Several of the galaxies were resolved by
the Nancay 3.6' E-W beam, so global parameters were derived from multiple-point
mapping observations. Typical HI masses for our sample are ~10^10 Msun, with
M_HI/L_B=0.3-1.7 (in solar units). All of the observed galaxies have published
optical surface photometry, and we have compiled key optical measurements for
these objects from the literature. We frequently find significant variations
among physical parameters of giant LSB galaxies reported by various workers.Comment: accepted to Astronomy and Astrophysics Supplements; 14 pages;
improved table formattin
Submillimetre and far-infrared spectral energy distributions of galaxies: the luminosity-temperature relation and consequences for photometric redshifts
The spectral energy distributions (SEDs) of dusty high-redshift galaxies are
poorly sampled in frequency and spatially unresolved. Their form is crucially
important for estimating the large luminosities of these galaxies accurately,
for providing circumstantial evidence concerning their power sources, and for
estimating their redshifts in the absence of spectroscopic information. We
discuss the suite of parameters necessary to describe their SEDs adequately
without introducing unnecessary complexity. We compare directly four popular
descriptions, explain the key degeneracies between the parameters in each when
confronted with data, and highlight the differences in their best-fitting
values. Using one representative SED model, we show that fitting to even a
large number of radio, submillimetre and far-infrared (far-IR) continuum
colours provides almost no power to discriminate between the redshift and dust
temperature of an observed galaxy, unless an accurate relationship with a tight
scatter exists between luminosity and temperature for the whole galaxy
population. We review our knowledge of this luminosity-dust temperature
relation derived from three galaxy samples, to better understand the size of
these uncertainties. Contrary to recent claims, we stress that far-IR-based
photometric redshifts are unlikely to be sufficiently accurate to impose useful
constraints on models of galaxy evolution: finding spectroscopic redshifts for
distant dusty galaxies will remain essential.Comment: 14 pages, 14 figures, in press at MNRAS. Replaced with final updated
proof versio
The correlation between reading and mathematics ability at age twelve has a substantial genetic component
Dissecting how genetic and environmental influences impact on learning is helpful for maximizing numeracy and literacy. Here we show, using twin and genome-wide analysis, that there is a substantial genetic component to children’s ability in reading and mathematics, and estimate that around one half of the observed correlation in these traits is due to shared genetic effects (so-called Generalist Genes). Thus, our results highlight the potential role of the learning environment in contributing to differences in a child’s cognitive abilities at age twelve
Genetic determinants of cortical structure (thickness, surface area and volumes) among disease free adults in the CHARGE Consortium
Cortical thickness, surface area and volumes (MRI cortical measures) vary with age and cognitive function, and in neurological and psychiatric diseases. We examined heritability, genetic correlations and genome-wide associations of cortical measures across the whole cortex, and in 34 anatomically predefined regions. Our discovery sample comprised 22,824 individuals from 20 cohorts within the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium and the United Kingdom Biobank. Significant associations were replicated in the Enhancing Neuroimaging Genetics through Meta-analysis (ENIGMA) consortium, and their biological implications explored using bioinformatic annotation and pathway analyses. We identified genetic heterogeneity between cortical measures and brain regions, and 160 genome-wide significant associations pointing to wnt/β-catenin, TGF-β and sonic hedgehog pathways. There was enrichment for genes involved in anthropometric traits, hindbrain development, vascular and neurodegenerative disease and psychiatric conditions. These data are a rich resource for studies of the biological mechanisms behind cortical development and aging
Myeloperoxidase-dependent oxidation of etoposide in human myeloid progenitor CD34+ cells
ABSTRACT Etoposide is a widely used anticancer drug successfully utilized for treatment of many types of cancer in children and adults. Its use, however, is associated with an increased risk of development of secondary acute myelogenous leukemia (t-AML) involving MLL gene MOL #68718
Sherman, Shakers, and Shenanigans
The first 122 pages of this book relate to Bulloch County and form Book 10: Readings in Bulloch County History. The remainder comprise the Southern Folkways Journal Review No. 3, and relate to Southeast Georgia and to the Southeastern region of the United States. The first collection begins with a poem by Dr. John Ransom Lewis, followed by three articles on Dan Bland and the biographies of prominent African American citizens. Also included are two articles on the Hardy Moore family, student papers on vanishing Bulloch County communities, information on Joseph Jackson, articles on three local churches, and the Muster Roll of Toombs Guards. The second section of this book begins with an article on Western Shakers by Dr. Dale Covington, followed by “Hostau Reminisces,” and several articles on the Cherokee and the Lumbee Indians.https://digitalcommons.georgiasouthern.edu/bchs-pubs/1033/thumbnail.jp
Amyloid-Associated Nucleic Acid Hybridisation
Nucleic acids promote amyloid formation in diseases including Alzheimer's
and Creutzfeldt-Jakob disease. However, it remains unclear whether the close
interactions between amyloid and nucleic acid allow nucleic acid secondary
structure to play a role in modulating amyloid structure and function. Here we
have used a simplified system of short basic peptides with alternating
hydrophobic and hydrophilic amino acid residues to study nucleic acid - amyloid
interactions. Employing biophysical techniques including X-ray fibre
diffraction, circular dichroism spectroscopy and electron microscopy we show
that the polymerized charges of nucleic acids concentrate and enhance the
formation of amyloid from short basic peptides, many of which would not
otherwise form fibres. In turn, the amyloid component binds nucleic acids and
promotes their hybridisation at concentrations below their solution
Kd, as shown by time-resolved FRET studies. The
self-reinforcing interactions between peptides and nucleic acids lead to the
formation of amyloid nucleic acid (ANA) fibres whose properties are distinct
from their component polymers. In addition to their importance in disease and
potential in engineering, ANA fibres formed from prebiotically-produced peptides
and nucleic acids may have played a role in early evolution, constituting the
first entities subject to Darwinian evolution
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