4,743 research outputs found
Ohio Strip Mine Spoils: Physico-Chemical and Microbiological Characterization and Changes Due to Liming and Organic Additions
Author Institution: Department of Zoological and Biomedical Sciences, Ohio UniversitySoutheastern Ohio strip mine spoils and garden soil were characterized physico-chemically and microbiologically. Spoils, limed spoils and garden soil that had been sterilized were amended with cellulose or sucrose and some minerals, including ammonium-nitrogen. The samples were inoculated with microbes from a garden compost infusion and incubated for 3 wk at 25 C. Soil water content was held at 80% field capacity. Changes in microbial populations, nitrate concentration and soil aggregation were followed for 3 wk. Microbial populations and soil aggregation increased mostly during the first week in all samples. Molds predominated in acid spoils while bacteria and actinomycetes declined. In limed spoils and garden soil bacteria and actinomycetes outgrew the molds. In spite of the inoculation with nitrifying bacteria, nitrification did not occur in acid spoils but continued for 3 wk in the other samples. It was shown that liming and proper amendments did improve the characteristics of acid spoils
Noise-Activated Escape from a Sloshing Potential Well
We treat the noise-activated escape from a one-dimensional potential well of
an overdamped particle, to which a periodic force of fixed frequency is
applied. We determine the boundary layer behavior, and the physically relevant
length scales, near the oscillating well top. We show how stochastic behavior
near the well top generalizes the behavior first determined by Kramers, in the
case without forcing. Both the case when the forcing dies away in the weak
noise limit, and the case when it does not, are examined. We also discuss the
relevance of various scaling regimes to recent optical trap experiments.Comment: 9 pages, no figures, REVTeX, expanded versio
Responsiveness of the innate immune system and glucose concentrations in the oldest old
Abstract Patients with diabetes mellitus show in-creased risk of infectious disease as well as dis-turbances in innate immunity. In critical care settings, hyperglycemia is associated with increased risk of sepsis. It is unclear whether elevated glucose concen-trations and innate immunity are associated in a non-clinical setting. We aimed to assess the association between glucose concentrations and innate immune response in the oldest old, who are at increased risk of both disturbed glucose metabolism as well as infec-tious disease. This study was part of the Leiden 85-plus Study. In 562 subjects aged 85 years old of the general population, venous blood samples were taken for measurement of morning glucose, C-reactive protein (CRP) and glycated hemoglobin (HbA1c). The innate immune response was assessed by performing ex vivo whole blood lipopolysaccharide (LPS) stimulation for production capacity of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 1-beta (IL1-β), interleukin 10 (IL-10) and interleukin 1 receptor antagonist (IL-1Ra). Using linear regression analysis, cross-sectional analysis between glucose and cytokine production capacity was performed. We found a significant negative association between glucose concentrations, but not HbA1c, and cytokine response capacity in four out of five measured cytokines (all p<0.05). Both glucose and HbA1c were positively associated with circulat-ing levels of CRP. Higher glucose concentrations in non-diabetic elderly are associated with lower innate immune response. As elderly show increased vulner-ability for disturbances in glucose metabolism as well as infectious disease, this relation could be of clinical significance
Oxygen abundances of zCOSMOS galaxies at z ∼ 1.4 based on five lines and implications for the fundamental metallicity relation
A relation between the stellar mass M and the gas-phase metallicity Z of galaxies, the MZR, is observed up to higher redshifts. It is a matter of debate, however, if the SFR is a second parameter in the MZR. To explore this issue at z > 1, we used VLT-SINFONI near-infrared (NIR) spectroscopy of eight zCOSMOS galaxies at 1.3 < z < 1.4 to measure the strengths of four emission lines: Hβ, [OIII]λ5007, Hα, and [NII]λ6584, additional to [OII]λ3727 measured from VIMOS. We derive reliable O/H metallicities based on five lines, and also SFRs from extinction corrected Hα measurements. We find that the MZR of these star-forming galaxies at z ≈ 1.4 is lower than the local SDSS MZR by a factor of three to five, a larger change than reported in the literature using [NII]/Hα-based metallicities from individual and stacked spectra. Correcting N2-based O/Hs using recent results by Newman et al. (2014), also the larger FMOS sample at z ∼ 1.4 of Zahid et al. (2014) shows a similar evolution of the MZR like the zCOSMOS objects. These observations seem also in agreement with a non-evolving FMR using the physically motivated formulation of the FMR from Lilly et al. (2013
Changes in lipid composition during sexual development of the malaria parasite Plasmodium falciparum
Abstract
Background
The development of differentiated sexual stages (gametocytes) within human red blood cells is essential for the propagation of the malaria parasite, since only mature gametocytes will survive in the mosquito’s midgut. Hence gametocytogenesis is a pre-requisite for transmission of the disease. Physiological changes involved in sexual differentiation are still enigmatic. In particular the lipid metabolism—despite being central to cellular regulation and development—is not well explored.
Methods
Here the lipid profiles of red blood cells infected with the five different sexual stages of Plasmodium falciparum were analysed by mass spectrometry and compared to those from uninfected and asexual trophozoite infected erythrocytes.
Results
Fundamental differences between erythrocytes infected with the different parasite stages were revealed. In mature gametocytes many lipids that decrease in the trophozoite and early gametocyte infected red blood cells are regained. In particular, regulators of membrane fluidity, cholesterol and sphingomyelin, increased significantly during gametocyte maturation. Neutral lipids (serving mainly as caloriometric reserves) increased from 3 % of total lipids in uninfected to 27 % in stage V gametocyte infected red blood cells. The major membrane lipid class (phospholipids) decreased during gametocyte development.
Conclusions
The lipid profiles of infected erythrocytes are characteristic for the particular parasite life cycle and maturity stages of gametocytes. The obtained lipid profiles are crucial in revealing the lipid metabolism of malaria parasites and identifying targets to interfere with this deadly disease.We are grateful to the Australian Red Cross for providing human RBCs and
serum. Support of the Australian Research Council is acknowledged. TWM
is an Australian Research Council Future Fellow (FT110100249)
SPHERES, J\"ulich's High-Flux Neutron Backscattering Spectrometer at FRM II
SPHERES (SPectrometer with High Energy RESolution) is a third-generation
neutron backscattering spectrometer, located at the 20 MW German neutron source
FRM II and operated by the Juelich Centre for Neutron Science. It offers an
energy resolution (fwhm) better than 0.65 micro-eV, a dynamic range of +-31
micro-eV, and a signal-to-noise ratio of up to 1750:1.Comment: 12 pages, 7 figures, 2 tables. Supplemental material consists of 3
pages, 2 figures, 2 table
Systemic Lupus Erythematosus With Isolated Psychiatric Symptoms and Antinuclear Antibody Detection in the Cerebrospinal Fluid
Background: Organic psychiatric disorders can be caused by immunological disorders, such as autoimmune encephalitis or systemic lupus erythematosus (SLE). SLE can affect most organs, as well as the central nervous system (CNS). In this paper, we describe a patient with an isolated psychiatric syndrome in the context of SLE and discuss the role of antibody detection in the cerebrospinal fluid (CSF).Case presentation: The 22-year-old German male high school graduate presented with obsessive–compulsive and schizophreniform symptoms. He first experienced obsessive–compulsive symptoms at the age of 14. At the age of 19, his obsessive thoughts, hallucinations, diffuse anxiety, depressed mood, severe dizziness, and suicidal ideation became severe and did not respond to neuroleptic or antidepressant treatment. Due to increased antinuclear antibodies (ANAs) with anti-nucleosome specificity in serum and CSF, complement activation, multiple bilateral white matter lesions, and inflammatory CSF alterations, we classified the complex syndrome as an isolated psychiatric variant of SLE. Immunosuppressive treatment with two times high-dose steroids, methotrexate, and hydroxychloroquine led to a slow but convincing improvement.Conclusion: Some patients with psychiatric syndromes and increased ANA titers may suffer from psychiatric variants of SLE, even if the American College of Rheumatology criteria for SLE are not met. Whether the psychiatric symptoms in our patient represent a prodromal stage with the later manifestation of full-blown SLE or a subtype of SLE with isolated CNS involvement remains unclear. Regardless, early diagnosis and initiation of immunosuppressive treatment are essential steps in preventing further disease progression and organ damage. Intrathecal ANAs with extractable nuclear antigen differentiation may be a more sensitive marker of CNS involvement compared with serum analyses alone
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