Chronic inappropriate immune activation is the central defect-driving loss of CD4(+) T helper cells and progression to AIDS in persons with HIV-1 infection, but the mechanisms remain controversial. ...We examined key regulatory invariant receptor natural killer T (iNKT) cells in the gut, the largest reservoir of lymphocytes and a key arena of HIV-1 pathogenesis. In healthy control persons, the anti-inflammatory CD4(+) iNKT-cell subset predominated over the pro-inflammatory CD4(-) iNKT-cell subset in the gut, but not in the blood, compartment. HIV-1 infection resulted in a preferential loss of this anti-inflammatory CD4(+) iNKT-cell subset within the gut. The degree of loss of the CD4(+) iNKT-cell subset in the gut, but not in the blood, correlated to the systemic immune activation and exhaustion that have been linked to disease progression. These results suggest a potentially important contribution of gut iNKT-cell imbalance in determining the systemic immune activation that is the hallmark of HIV-1 pathogenesis.
As a part of our ongoing Volume-limited A-Star (VAST) adaptive optics survey, we have obtained observations of 26 binary systems with projected separations <100 au, 13 of which have sufficient ...historical measurements to allow for refinement of their orbital elements. For each system with an estimated orbit, the dynamical system mass obtained was compared with the system mass estimated from mass-magnitude relations. Discrepancies between the dynamical and theoretical system mass can be explained by the presence of a previously unresolved spectroscopic component or by a non-solar metallicity of the system. Using this approach to infer the presence of additional companions, a lower limit to the fraction of binaries, triples and quadruples can be estimated as 39, 46 and 15 per cent for systems with at least one companion within 100 au. The fraction of multiple systems with three or more components shows a relative increase compared to the fraction for solar-type primaries resolved in previous volume-limited surveys. The observations have also revealed a pair of potentially young (<100 Myr) M dwarf companions, which would make an ideal benchmark for the theoretical models during the pre-main-sequence contraction phase for M dwarfs. In addition to those systems with orbit fits, we report 13 systems for which further orbital monitoring observations are required, 11 of which are newly resolved as a part of the VAST survey.
Respiratory system is the major route of entry for airborne particulates, being the effect on the human organism dependent on chemical composition of the particles, exposure time and individual ...susceptibility. Airborne particulate trace metals are considered to represent a health hazard since they may be absorbed into human lung tissues during breathing. Fossil fuel and wood combustion, as well as waste incineration and industrial processes, are the main anthropic sources of metals to the atmosphere. In urban areas, vehicular emissions—and dust resuspension associated to road traffic—become the most important manmade source.
This work investigated the atmospheric concentrations of TSP, PM
10 and elements such as iron, manganese, copper and zinc, from three different sites around Salvador Region (Bahia, Brazil), namely: (i)
Lapa Bus Station, strongly impacted by heavy-duty diesel vehicles; (ii)
Aratu harbor, impacted by an intense movement of goods, including metal ores and concentrates and near industrial centers and; (iii)
Bananeira Village located on Maré Island, a non-vehicle-influenced site, with activities such as handcraft work and fishery, although placed near the port. Results have pointed out that TSP concentrations ranged between 16.9 (Bananeira) and 354.0
μg
m
−3 (Aratu#1), while for PM
10 they ranged between 30.9 and 393.0
μg
m
−3, both in the Lapa Bus Station. Iron was the major element in both Lapa Station and Aratu (#1 and #2), with average concentrations in the PM
10 samples of 148.9, 79.6 and 205.0
ng
m
−3, respectively. Zinc, on the other hand, was predominant in samples from Bananeira, with an average concentration of 145.0
ng
m
−3 in TSP samples, since no PM
10 sample was taken from this site. The main sources of iron in the Lapa Station and Aratu harbor were, respectively, soil resuspension by buses and discharge of solid granaries, as fertilizers and metal ores. On the other hand, zinc and copper in the bus station were mainly from anthropic contributions, probably heavy-duty vehicle ageing and wearing actions releasing off Zn from tires and Cu from brake linings. In the Aratu harbor, the high copper concentrations found were probably due to the port's activities, as discharges of copper concentrate on its terminal, although other sources could be possible, as burning of diesel fuel on ships and heavy oil in heaters. Finally, the Bananeira site has been presented as a different profile, since this remote site has shown zinc as the most abundant element, demonstrating to have an unexpected anthropic contribution. On a mass-to-mass basis, both zinc and manganese were in high levels in the Bananeira site and their presence strongly suggest the impact of other sources, such as the Industrial Center of Aratu and/or a siderurgy plant, not far away from that location.
Studies of cake batter rheology have focused on viscous behaviour. We demonstrate that elastic effects dominate at the shear rates used in commercial mixers. The development of batter structure was ...investigated for two flour types using two bench-scale planetary mixers with known shear rate profiles (Kenwood-KM250, maximum 100
s
−1; Hobart-N50, 500
s
−1). These wet foams (air volume fraction 0.39–0.45) showed shear-thinning behaviour at low shear rates (0.1–10
s
−1), with apparent viscosity dependent on air volume fraction. Simple shear thinning behaviour ceased, for foams, above 10–20
s
−1: for slurries (air volume fraction, 0.11–0.15) the limit approached 100
s
−1. Elastic effects, predominantly arising from the bubble phase, therefore dominate cake batter behaviour at the shear rates experienced in commercial mixers. Filament thinning extensional rheometry confirmed the VE behaviour of batters. These results indicate that visco-elastic analyses are likely to be the most appropriate probe of microstructure in cake batters.
Enantioselective Friedel−Crafts alkylation reactions of a series of substituted indoles with methyl trifluoropyruvate, catalyzed by a chiral nonracemic C 2-symmetric 2,2‘-bipyridyl copper(II) ...triflate complex, are described. The corresponding 3,3,3-trifluoro-2-hydroxy-2-indole-3-yl-propionic acid methyl esters were formed in good yield and in high enantiomeric excess (up to 90%). This is the first report of the use of a chiral nonracemic 2,2‘-bipyridyl ligand in catalytic and enantioselective Friedel−Crafts alkylation reactions. The structural characterization of a copper(II) chloride complex of the chiral 2,2‘-bipyridyl ligand by X-ray crystallography is also presented.
Little is known about the molecular basis of organelle size control in eukaryotes. Cells of the biflagellate alga Chlamydomonas reinhardtii actively maintain their flagella at a precise length. ...Chlamydomonas mutants that lose control of flagellar length have been isolated and used to demonstrate that a dynamic process keeps flagella at an appropriate length 1, 2. To date, none of the proteins required for flagellar length control have been identified in any eukaryotic organism. Here, we show that a novel MAP kinase is crucial to enforcing wild-type flagellar length in C. reinhardtii. Null mutants of LF42, a gene encoding a protein with extensive amino acid sequence identity to a mammalian MAP kinase of unknown function, MOK 3, are unable to regulate the length of their flagella. The LF4 protein (LF4p) is localized to the flagella, and in vitro enzyme assays confirm that the protein is a MAP kinase. The long-flagella phenotype of lf4 cells is rescued by transformation with the cloned LF4 gene. The demonstration that a novel MAP kinase helps enforce flagellar length control indicates that a previously unidentified signal transduction pathway controls organelle size in C. reinhardtii.
This note is a follow-up, update, and correction of 'The Union of Two Worlds: Reconstructing Elements of Proto-Athabaskan Folklore and Religion', published in Folklore in 2016. First, the note ...addresses evidence presented by a new publication. Next, it adds an omitted illustration of the comparison of a Navajo 'Big Fly' with a Tibetan 'enemy god'. Finally, it corrects a small-but-meaningful error and clarifies a resulting interpretation about the Huns in Buddhist literature.
PDF
