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Willamette and associated soils on late Pleistocene geomorphic surfaces, Polk County, Oregon
The morphology and genesis of soils of the Willamette series
and of some Willamette-associated soils and their relationships to
geomorphic surfaces were studied in an area near McCoy, Polk
County, Oregon. Influences of regional extent, such as climate and
parent material, were related to the soils and landforms. The soils
were mapped by methods proscribed in the Soil Survey Manual, and
the geomorphic surfaces were recognized and delimited using descriptions
previously published. Interpretations of the soil and geomorphic
relationships were extended to other portions of the northern
Willamette Valley, particularly the Yamhill River Valley.
Of four geomorphic surfaces mapped in the study area, three
were previously recognized, and a new one, the Bethel surface, was
proposed. It was described and compared to the Quad surface in the
Willamette Valley, and is presumably of similar age. The other
geomorphic surfaces in the area were mapped as Calapooyia, Senecal,
and Ingram units. Stratigraphic investigations identified the nature of
the materials under the surfaces.
Chemical and physical analyses were made of samples from
horizons of representative soil profiles. The laboratory data were
used to compare and contrast soils of the different surfaces. The
Willamette "group" of soils, which occur on three of the surfaces,
were found to be similar. They are members of fine-silty, mixed,
mesic families of Pachic Ultic Haploxerolls, Ultic Argixerolls,
Pachic Ultic Argixerolls, and Aquultic Argixerolls, a topo-chronolitho
(perhaps bio-) sequence. Soils of the subgroups Argiaquic Xeric
Argialbolls, Typic Ochraqualfs, and Typic Albaqualfs are limited
to two geomorphic surfaces, and one soil, a member of Fluventic
Haplaquolls, is on only one surface, the youngest mapped in the study
area. Litho logic discontinuities, correlated with stratigraphic
evidence, were observed in and recorded for each soil profile
described.
Each of the soils that was recognized and analyzed is comprised
of more than one deposit. The upper limit of the older material in the
sola is marked by brown and reddish brown clay films on ped faces,
probably the result of clay illuviation prior to the deposition of the
next major stratum. Modification of the strata by additions of
organic matter, eluviation of bases, reduction of iron and manganese
under wet conditions, local erosion and deposition of alluvium, and possibly alteration under different kinds of vegetation produced different
morphologies of the soils, depending on the topographic locations
and nature of the strata. Soils on the hilltops, the Bethel surface,
have thinner mollic epipedons than do other Willamette "group"
soils on the main valley terrace, the Senecal surface. The clayey
strata under the Calapooyia and Ingram surfaces, although deposited
at different times, affected the soils on those surfaces similarly by
restricting the downward movement of water. Reducing conditions in
all of the soils sometime during the rainy season was considered.
Cool, moist winters and warm, dry summers affected the kinds and
rates of chemical reactions in the soils. The observations made in
the study area are applicable to similar areas in other parts of the
Willamette Valley. During the progress of the Polk County soil survey,
careful examination of the soils associated with the Bethel surface
is important
Nuclear imaging does not have clear added value in patients with low a priori chance of periprosthetic joint infection. A retrospective single-center experience
Background: A low-grade periprosthetic joint infection (PJI) may present without specific symptoms, and its diagnosis remains a challenge. Three-phase bone scintigraphy (TPBS) and white blood cell (WBC) scintigraphy are incorporated into recently introduced diagnostic criteria for PJI, but their exact value in diagnosing low-grade PJI in patients with nonspecific symptoms remains unclear. Methods: In this retrospective study, we evaluated patients with a prosthetic joint of the hip or knee who underwent TPBS and/or WBC scintigraphy between 2009 and 2016 because of nonspecific symptoms. We reviewed and calculated diagnostic accuracy of the TPBS and/or WBC scintigraphy to diagnose or exclude PJI. PJI was defined based on multiple cultures obtained during revision surgery. In patients who did not undergo revision surgery, PJI was ruled out by clinical follow-up of at least 2 years absent of clinical signs of infection based on MSIS 2011 criteria. Results: A total of 373 patients were evaluated, including 340 TPBSs and 142 WBC scintigraphies. Thirteen patients (3.5 %) were diagnosed with a PJI. TPBS sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were 71 %, 65 %, 8 % and 98 %, respectively. Thirty-five percent of TPBS showed increased uptake. Stratification for time intervals between the index arthroplasty and the onset of symptoms did not alter its diagnostic accuracy. WBC scintigraphy sensitivity, specificity, PPV and NPV were 30 %, 90 %, 25 % and 94 %, respectively. Conclusion: Nuclear imaging does not have clear added value in patients with low a priori chance of periprosthetic joint infection
F-18-FDG-PET uptake in non-infected total hip prostheses
Background and purpose - F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) can be used in the diagnostic work-up of a patient with suspected periprosthetic joint infection (PJI) but, due to a lack of accurate interpretation criteria, this technique is not routinely applied. Since the physiological uptake pattern of FDG around a joint prosthesis is not fully elucidated, we determined the physiological FDG uptake in non-infected total hip prostheses. Patients and methods - Patients treated with primary total hip arthroplasty (1995-2016) who underwent a FDG-PET/CT for an indication other than a suspected PJI were retrospectively evaluated. Scans were both visually and quantitatively analyzed. Semi-quantitative analysis was performed by calculating maximum and peak standardized uptake values (SUVmax and SUVpeak) by volume of interests (VOIs) at 8 different locations around the prosthesis. Results - 58 scans from 30 patients were analyzed. In most hips, a diffuse heterogeneous uptake pattern around the prosthesis was observed (in 32/38 of the cemented prostheses, and in 16/20 of the uncemented prostheses) and most uptake was located around the neck of the prosthesis. The median SUVmax in the cemented group was 2.66 (95% CI 2.51-3.10) and in the uncemented group 2.87 (CI 2.65-4.63) (Median difference = -0.36 [CI -1.2 to 0.34]). In uncemented prostheses, there was a positive correlation in time between the age of the prosthesis and the FDG uptake (r(s) = 0.63 [CI 0.26-0.84]). Interpretation - Our study provides key data to develop accurate interpretation criteria to differentiate between physiological uptake and infection in patients with a prosthetic joint.</p
VLBA polarimetric observations of the CSS quasar 3C147
Aims. We report new VLBA polarimetric observations of the compact
steep-spectrum (CSS) quasar 3C147 (B0538+498) at 5 and 8.4GHz.
Methods. By using multifrequency VLBA observations, we derived
milliarcsecond-resolution images of the total intensity, polarisation, and
rotation measure distributions, by combining our new observations with archival
data.
Results. The source shows a one-sided structure, with a compact region, and a
component extending about 200 mas to the south-west. The compact region is
resolved into two main components with polarised emission, a complex rotation
measure distribution, and a magnetic field dominated by components
perpendicular to the source axis.
Conclusions. By considering all the available data, we examine the possible
location of the core component, and discuss two possible interpretations of the
observed structure of this source: core-jet and lobe-hot spot. Further
observations to unambiguously determine the location of the core would help
distinguish between the two possibilities discussed here.Comment: 11 pages, 12 figure
Reversal of hemochromatosis by apotransferrin in non-transfused and transfused Hbbth3/+ (heterozygous b1/b2 globin gene deletion) mice
HST/STIS low dispersion spectroscopy of three Compact Steep Spectrum sources Evidence for jet-cloud interaction
We present Hubble Space Telescope Imaging Spectrograph long-slit spectroscopy
of the emission line nebulae in the compact steep spectrum radio sources 3C 67,
3C 277.1, and 3C 303.1. We derive BPT (Baldwin- Philips-Terlevich; Baldwin et
al. 1981) diagnostic emission line ratios for the nebulae which are consistent
with a mix of shock excitation and photoionization in the extended gas. In
addition, line ratios indicative of lower ionization gas are found to be
associated with higher gas velocities. The results are consistent with a
picture in which these galaxy scale radio sources interact with dense clouds in
the interstellar medium of the host galaxies, shocking the clouds thereby
ionizing and accelerating them.Comment: Accepted for publication in A&A. 6 pages, 8 figure
Endothelial and Inflammation Biomarker Profiles at Diagnosis Reflecting Clinical Heterogeneity and Serving as a Prognostic Tool For Treatment Response in Two Independent Cohorts of Patients With Juvenile Dermatomyositis
Objective: Juvenile dermatomyositis (DM) is a heterogeneous systemic immune-mediated vasculopathy. This study was undertaken to 1) identify inflammation/endothelial dysfunction–related biomarker profiles reflecting disease severity at diagnosis, and 2) establish whether such biomarker profiles could be used for predicting the response to treatment in patients with juvenile DM. Methods: In total, 39 biomarkers related to activation of endothelial
HI absorption in 3C 49 and 3C 268.3. Probing the environment of Compact Steep Spectrum and GHz Peaked Spectrum sources
We present and discuss European VLBI Network UHF band spectral line
observations, made to localise the redshifted 21cm HI absorption known to occur
in the subgalactic sized compact steep spectrum galaxies 3C 49 and 3C 268.3. We
have detected HI absorption towards the western radio lobe of 3C 49 and the
northern lobe of 3C 268.3. However, we cannot rule out the presence of similar
amounts of HI towards the opposite and much fainter lobes. The radio lobes with
detected HI absorption (1) are brighter and closer to the core than the
opposite lobes; (2) are depolarized; and (3) are associated with optical
emission line gas. The association between the HI absorption and the emission
line gas, supports the hypothesis that the HI absorption is produced in the
atomic cores of the emission line clouds. Our results are consistent with a
picture in which compact steep spectrum sources interact with clouds of dense
gas as they propagate through their host galaxy. We suggest that the
asymmetries in the radio and optical emission can be due to interaction of a
two sided radio source with an asymmetric distribution of dense clouds in their
environment.Comment: 7 pages, 6 figures. Accepted in A&
NCF1 gene and pseudogene pattern: association with parasitic infection and autoimmunity
<p>Abstract</p> <p>Background</p> <p>Neutrophil cytosolic factor 1, p47<sup>phox </sup>(NCF1) is a component of the leukocyte NADPH oxidase complex mediating formation of reactive oxygen intermediates (ROI) which play an important role in host defense and autoimmunity. An individual genomic pattern of <it>ncf1 </it>and its two types of pseudogenes (reflected by the ΔGT/GTGT ratio) may influence the individual capacity to produce ROI.</p> <p>Methods</p> <p>NCF1ΔGT/GTGT ratios were correlated with clinical parameters and ROI production during <it>Plasmodium falciparum </it>malaria and with susceptibility to the autoimmune disease multiple sclerosis (MS).</p> <p>Results</p> <p>Among Gabonese children with severe malaria, ROI production from peripheral blood tended to be higher in individuals with a ΔGT/GTGT ratio ≤ 1:1. ΔGT/GTGT ratios were not associated with susceptibility to MS, but to age-of-onset among MS patients.</p> <p>Conclusion</p> <p>The genomic pattern of <it>NCF1 </it>and its pseudogenes might influence ROI production but only marginally influence susceptibility to and outcome of malaria and MS.</p
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