1,433 research outputs found
The Iowan Terrace and Terrace Soils of the Nishnabotna Valley in Western Iowa
Smith and Riecken (1947) in their revision of the Iowan-drift border in northwestern Iowan, extended a sublobe of the Iowandrift southward to near Roselle and Halbur in Carroll County. During field studies in Carroll County in 1953, the margin of the Iowan-drift sublobe was found to extend as far southward as Manning and Templeton in Carroll County (Figure 1). The Iowan drift is delineated from the loess-mantled Kansan drift on the basis of four lines of evidence: (1) in topographic positions that preclude significant erosion on the Iowan-drift surface, calcareous loess overlies calcareous till. (2) In topographic positions that preclude significant erosion on the Kansan-drift surface, calcareous loess overlies a leached, buried soil in the uppermost part of the Kansan till. (3) An abrupt change in topography occurs at the margin of the Iowan-drift. (4) A discontinuity in loess thickness occurs at the margin of the Iowan-drift
Linear stability analysis of capillary instabilities for concentric cylindrical shells
Motivated by complex multi-fluid geometries currently being explored in
fibre-device manufacturing, we study capillary instabilities in concentric
cylindrical flows of fluids with arbitrary viscosities, thicknesses,
densities, and surface tensions in both the Stokes regime and for the full
Navier--Stokes problem. Generalizing previous work by Tomotika (N=2), Stone &
Brenner (N=3, equal viscosities) and others, we present a full linear stability
analysis of the growth modes and rates, reducing the system to a linear
generalized eigenproblem in the Stokes case. Furthermore, we demonstrate by
Plateau-style geometrical arguments that only axisymmetric instabilities need
be considered. We show that the N=3 case is already sufficient to obtain
several interesting phenomena: limiting cases of thin shells or low shell
viscosity that reduce to N=2 problems, and a system with competing breakup
processes at very different length scales. The latter is demonstrated with full
3-dimensional Stokes-flow simulations. Many cases remain to be
explored, and as a first step we discuss two illustrative cases,
an alternating-layer structure and a geometry with a continuously varying
viscosity
Can loss of agency and oppositional perturbation associated with antidepressant monotherapy and low-fidelity psychological treatment dilute the benefits of guideline-consistent depression treatment at the population level?
Contains fulltext :
226202.pdf (publisher's version ) (Open Access
Obligate Biotroph Pathogens of the Genus Albugo Are Better Adapted to Active Host Defense Compared to Niche Competitors
Recent research suggested that plants behave differently under combined versus single abiotic and biotic stress conditions in controlled environments. While this work has provided a glimpse into how plants might behave under complex natural conditions, it also highlights the need for field experiments using established model systems. In nature, diverse microbes colonize the phyllosphere of Arabidopsis thaliana, including the obligate biotroph oomycete genus Albugo, causal agent of the common disease white rust. Biotrophic, as well as hemibiotrophic plant pathogens are characterized by efficient suppression of host defense responses. Lab experiments have even shown that Albugo sp. can suppress non-host resistance, thereby enabling otherwise avirulent pathogen growth. We asked how a pathogen that is vitally dependent on a living host can compete in nature for limited niche space while paradoxically enabling colonization of its host plant for competitors? To address this question, we used a proteomics approach to identify differences and similarities between lab and field samples of Albugo sp.-infected and -uninfected A. thaliana plants. We could identify highly similar apoplastic proteomic profiles in both infected and uninfected plants. In wild plants, however, a broad range of defense-related proteins were detected in the apoplast regardless of infection status, while no or low levels of defense-related proteins were detected in lab samples. These results indicate that Albugo sp. do not strongly affect immune responses and leave distinct branches of the immune signaling network intact. To validate our findings and to get mechanistic insights, we tested a panel of A. thaliana mutant plants with induced or compromised immunity for susceptibility to different biotrophic pathogens. Our findings suggest that the biotroph pathogen Albugo selectively interferes with host defense under different environmental and competitive pressures to maintain its ecological niche dominance. Adaptation to host immune responses while maintaining a partially active host immunity seems advantageous against competitors. We suggest a model for future research that considers not only host–microbe but in addition microbe–microbe and microbe–host environment factors
An algorithm to obtain global solutions of the double confluent Heun equation
A procedure is proposed to construct solutions of the double confluent Heun
equation with a determinate behaviour at the singular points. The connection
factors are expressed as quotients of Wronskians of the involved solutions.
Asymptotic expansions are used in the computation of those Wronskians. The
feasibility of the method is shown in an example, namely, the Schroedinger
equation with a quasi-exactly-solvable potential
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The Tabby cat locus maps to feline chromosome B1.
The Tabby markings of the domestic cat are unique coat patterns for which no causative candidate gene has been inferred from other mammals. In this study, a genome scan was performed on a large pedigree of cats that segregated for Tabby coat markings, specifically for the Abyssinian (Ta-) and blotched (tbtb) phenotypes. There was linkage between the Tabby locus and eight markers on cat chromosome B1. The most significant linkage was between marker FCA700 and Tabby (Z = 7.56, theta = 0.03). Two additional markers in the region supported linkage, although not with significant LOD scores. Pairwise analysis of the markers supported the published genetic map of the cat, although additional meioses are required to refine the region. The linked markers cover a 17-cM region and flank an evolutionary breakpoint, suggesting that the Tabby gene has a homologue on either human chromosome 4 or 8. Alternatively, Tabby could be a unique locus in cats
Transient study using LoTSS -- framework development and preliminary results
We present a search for transient radio sources on time-scales of seconds to
hours at 144 MHz using the LOFAR Two-metre Sky Survey (LoTSS). This search is
conducted by examining short time-scale images derived from the LoTSS data. To
allow imaging of LoTSS on short time-scales, a novel imaging and filtering
strategy is introduced. This includes sky model source subtraction, no cleaning
or primary beam correction, a simple source finder, fast filtering schemes and
source catalogue matching. This new strategy is first tested by injecting
simulated transients, with a range of flux densities and durations, into the
data. We find the limiting sensitivity to be 113 and 6 mJy for 8 second and 1
hour transients respectively. The new imaging and filtering strategies are
applied to 58 fields of the LoTSS survey, corresponding to LoTSS-DR1 (2% of the
survey). One transient source is identified in the 8 second and 2 minute
snapshot images. The source shows one minute duration flare in the 8 hour
observation. Our method puts the most sensitive constraints on/estimates of the
transient surface density at low frequencies at time-scales of seconds to
hours; at 1 hour at a sensitivity of 6.3
mJy; at 2 minutes at a sensitivity of 30
mJy; and at 8 seconds at a sensitivity of
113 mJy. In the future, we plan to apply the strategies presented in this paper
to all LoTSS data.Comment: submitted to MNRA
Impact of Comorbid Personality Disorders on Depression Treatment in Routine Outpatient Care
Item does not contain fulltextObjective: The impact of personality disorder on treatment effectiveness for depression has been debated, and study results have been inconsistent. However, studies that report a negative impact of personality disorders on depression treatment outcomes are often characterized by uncontrolled treatment designs. Within such contexts, individuals with depression and personality disorders are at risk to receive suboptimal treatment. The aim of this retrospective observational study was to investigate whether and to what extent comorbid personality disorders were associated with the type and amount of depression treatment received in routine outpatient care. Methods: Retrospectively extracted data from electronic records of 1,455 outpatients treated for depression at several sites of a nationwide mental health provider in the Netherlands were included. The type and number of treatment sessions and visits were analyzed by using regression models. Results: Individuals with depression and comorbid personality disorders received more psychotherapy sessions than individuals without personality disorders, irrespective of depression severity. The number of pharmacotherapy sessions and supportive and crisis visits did not differ between individuals with and without comorbid personality disorders. Conclusions: Individuals with depression and personality disorders received more intensive treatment than individuals without comorbid personality disorders. These results conflict with treatment guidelines and recommendations from high-quality studies and may be indicative of overtreatment among this large group of patients.7 p
Pain relief is associated with decreasing postural sway in patients with non-specific low back pain
Background
Increased postural sway is well documented in patients suffering from non-specific low back pain, whereby a linear relationship between higher pain intensities and increasing postural sway has been described. No investigation has been conducted to evaluate whether this relationship is maintained if pain levels change in adults with non-specific low back pain.
Methods
Thirty-eight patients with non-specific low back pain and a matching number of healthy controls were enrolled. Postural sway was measured by three identical static bipedal standing tasks of 90 sec duration with eyes closed in narrow stance on a firm surface. The perceived pain intensity was assessed by a numeric rating scale (NRS-11). The patients received three manual interventions (e.g. manipulation, mobilization or soft tissue techniques) at 3-4 day intervals, postural sway measures were obtained at each occasion.
Results
A clinically relevant decrease of four NRS scores in associated with manual interventions correlated with a significant decrease in postural sway. In contrast, if no clinically relevant change in intensity occurred ([less than or equal to]1 level), postural sway remained similar compared to baseline. The postural sway measures obtained at follow-up sessions 2 and 3 associated with specific NRS level showed no significant differences compared to reference values for the same pain score.
Conclusions
Alterations in self-reported pain intensities are closely related to changes in postural sway. The previously reported linear relationship between the two variables is maintained as pain levels change. Pain interference appears responsible for the altered sway in pain sufferers. This underlines the clinical use of sway measures as an objective monitoring tool during treatment or rehabilitation
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