1,034 research outputs found
Soil morphology, soil water, and forest tree growth on three Cumberland Plateau landtypes
Relationships among soil morphology, soil water, and forest tree growth were investigated on three forested Cumberland Plateau landtypes at two locations, and a forest land classification system was evaluated. Two soil pits on each plot were opened for morphological descriptions, characterization, and moisture cell installation. Moisture cells were read for two years. Thirty-two soil properties from three genetic soil horizons at 132 points located with a 10 meter grid were used in multivariate statistical analyses. Dominant soils were Typic Fragiudults on uplands; Humic Hapludults and Typic Fragiumbrepts on slopes; and Aquic Dystrochrepts and Typic Haplaquepts on first-order bottoms. Parent materials were Pleistocene loess over shale and sandstone residuum. Clay mineralogy of the upper sequum was relatively young. Chlorite was common in A horizons, but only acid upland soils contained hydroxy-interlayered vermiculite. Kaolinite and quartz dominated residual soils. Gibbsite was in the most leached soil horizons and within buried paleosols. Cation exchange capacities averaged 15 cmol(p+)kg-1 on uplands and bottoms and 20 cmol(p+)kg-1 on slopes. Base saturation ranged from less than 10 percent in bottoms to 45 percent in slope A horizons. Base saturation and cation exchange capacity increased as clay and organic matter increased. Soil moisture distribution in soil profiles and landscapes was related to soil morphology and landtypes respectively. Distribution of citrate-dithionite extractable Fe and Mn in profiles and landtypes was related to measured soil moisture distribution. Stem analysis of forest dominants revealed height growth related to the soil moisture gradient across the landscape. Site index of dominants on uplands and slopes increased down-slope, and yellow-poplar height on bottoms increased with increasing depth to the winter water table. Maximum likelihood factor analysis reduced 32 soil properties to four factors representing A horizon properties, soil texture, subsurface cations, and soil drainage and thickness. The 25 retained soil variables extracted 71 percent of the variance. Discriminant analysis classified all 132 grid observations into correct landtypes, revealing that measured soil properties were related to landtypes. The forest land classification system appears to be a viable method of grouping soils into units suitable for forest management on the Cumberland Plateau
A perfect storm : polycystic ovary syndrome masking underlying yype 1 Von Willebrand disease
Von Willebrand Disease (vWD) is the most common inherited bleeding diathesis worldwide and results in defects in von Willebrand Factor (vWF), inducing a hypocoagulable state. Polycystic Ovary Syndrome (PCOS) is characterized by chronic inflammation and hyperestrogenism, both of which induce acute phase reactions and increase serum levels of vWF and Factor VIII, yielding a prothrombotic state. These laboratory elevations may obscure the diagnosis of underlying vWD in patients with both conditions. We report a case of a 23 year-old female with PCOS and menorrhagia who presented prior to a surgical procedure for evaluation of bleeding risk
Using the XMM Optical Monitor to Study Cluster Galaxy Evolution
We explore the application of XMM-Newton Optical Monitor (XMM-OM) ultraviolet
(UV) data to study galaxy evolution. Our sample is constructed as the
intersection of all Abell clusters with z < 0.05 and having archival XMM-OM
data in either the UVM2 or UVW1 filters, plus optical and UV photometry from
the Sloan Digital Sky Survey and GALEX, respectively. The eleven resulting
clusters include 726 galaxies with measured redshifts, 520 of which have
redshifts placing them within their parent Abell clusters. We develop
procedures for manipulating the XMM-OM images and measuring galaxy photometry
from them, and confirm our results via comparison with published catalogs.
Color magnitude diagrams (CMDs) constructed using the XMM-OM data along with
SDSS optical data show promise for evolutionary studies, with good separation
between red and blue sequences and real variation in the width of the red
sequence that is likely indicative of differences in star formation history.
This is particularly true for UVW1 data, as the relative abundance of data
collected using this filter and its depth make it an attractive choice.
Available tools that use stellar synthesis libraries to fit the UV and optical
photometric data may also be used, thereby better describing star formation
history within the past Gyr and providing estimates of total stellar mass that
include contributions from young stars. Finally, color-color diagrams that
include XMM-OM UV data appear useful to the photometric identification of both
extragalactic and stellar sources.Comment: 44 pages with 14 figures, to appear in PAS
Understanding and Affecting Student Reasoning About Sound Waves
Student learning of sound waves can be helped through the creation of
group-learning classroom materials whose development and design rely on
explicit investigations into student understanding. We describe reasoning in
terms of sets of resources, i.e. grouped building blocks of thinking that are
commonly used in many different settings. Students in our university physics
classes often used sets of resources that were different from the ones we wish
them to use. By designing curriculum materials that ask students to think about
the physics from a different view, we bring about improvement in student
understanding of sound waves. Our curriculum modifications are specific to our
own classes, but our description of student learning is more generally useful
for teachers. We describe how students can use multiple sets of resources in
their thinking, and raise questions that should be considered by both
instructors and researchers.Comment: 23 pages, 4 figures, 3 tables, 28 references, 7 notes. Accepted for
publication in the International Journal of Science Educatio
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ATHENA: A Phase 3, Open-Label Study Of The Safety And Effectiveness Of Oliceridine (TRV130), A G-Protein Selective Agonist At The µ-Opioid Receptor, In Patients With Moderate To Severe Acute Pain Requiring Parenteral Opioid Therapy.
Background:Pain management with conventional opioids can be challenging due to dose-limiting adverse events (AEs), some of which may be related to the simultaneous activation of β-arrestin (a signaling pathway associated with opioid-related AEs) and G-protein pathways. The investigational analgesic oliceridine is a G-protein-selective agonist at the µ-opioid receptor with less recruitment of β-arrestin. The objective of this phase 3, open-label, multi-center study was to evaluate the safety and tolerability, of IV oliceridine for moderate to severe acute pain in a broad, real-world patient population, including postoperative surgical patients and non-surgical patients with painful medical conditions. Methods:Adult patients with a score ≥4 on 11-point NRS for pain intensity received IV oliceridine either by bolus or PCA; multimodal analgesia was permitted. Safety was assessed using AE reports, study discontinuations, clinical laboratory and vital sign measures. Results:A total of 768 patients received oliceridine. The mean age (SD) was 54.1 (16.1) years, with 32% ≥65 years of age. Most patients were female (65%) and Caucasian (78%). Surgical patients comprised the majority of the study population (94%), most common being orthopedic (30%), colorectal (15%) or gynecologic (15%) procedures. Multimodal analgesia was administered to 84% of patients. Oliceridine provided a rapid reduction in NRS pain score by 2.2 ± 2.3 at 30 mins from a score of 6.3 ± 2.1 (at baseline) which was maintained to the end of treatment. No deaths or significant cardiorespiratory events were reported. The incidence of AEs leading to early discontinuation and serious AEs were 2% and 3%, respectively. Nausea (31%), constipation (11%), and vomiting (10%) were the most common AEs. AEs were mostly of mild (37%) or moderate (25%) severity and considered possibly or probably related to oliceridine in 33% of patients. Conclusion:Oliceridine IV for the management of moderate to severe acute pain was generally safe and well tolerated in the patients studied. ClinicalTrialsgov identifier:NCT02656875
The Canada-UK Deep Submillimetre Survey: First Submillimetre Images, the Source Counts, and Resolution of the Background
We present the first results of a deep unbiased submillimetre survey carried
out at 450 and 850 microns. We detected 12 sources at 850 microns, giving a
surface density of sources with 850-micron flux densities > 2.8mJy of of
0.49+-0.16 per square arcmin. The sources constitute 20-30% of the background
radiation at 850 microns and thus a significant fraction of the entire
background radiation produced by stars. This implies, through the connection
between metallicity and background radiation, that a significant fraction of
all the stars that have ever been formed were formed in objects like those
detected here. The combination of their large contribution to the background
radiation and their extreme bolometric luminosities make these objects
excellent candidates for being proto-ellipticals. Optical astronomers have
recently shown that the UV-luminosity density of the universe increases by a
factor of about 10 between z=0 and z=1 and then decreases again at higher
redshifts. Using the results of a parallel submillimetre survey of the local
universe, we show that both the submillimetre source density and background can
be explained if the submillimetre luminosity density evolves in a similar way
to the UV-luminosity density. Thus, if these sources are ellipticals in the
process of formation, they may be forming at relatively modest redshifts.Comment: 8 pages (LATEX), 6 postscript figures, submitted to ApJ Letter
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