3,113 research outputs found
Altered Innate Immune Responses in Neutrophils from Patients with Well- and Suboptimally Controlled Asthma
© 2015 Francesca S. M. Tang et al. Background. Respiratory infections are a major cause of asthma exacerbations where neutrophilic inflammation dominates and is associated with steroid refractory asthma. Structural airway cells in asthma differ from nonasthmatics; however it is unknown if neutrophils differ. We investigated neutrophil immune responses in patients who have good (AGood) and suboptimal (ASubopt) asthma symptom control. Methods. Peripheral blood neutrophils from AGood (ACQ 0.75, n=7), and healthy controls (HC) (n=9) were stimulated with bacterial (LPS (1 g/mL), fMLF (100 nM)), and viral (imiquimod (3 g/mL), R848 (1.5 g/mL), and poly I:C (10 g/mL)) surrogates or live rhinovirus (RV) 16 (MOI1). Cell-free supernatant was collected after 1 h for neutrophil elastase (NE) and matrix metalloproteinase- (MMP-) 9 measurements or after 24 h for CXCL8 release. Results. Constitutive NE was enhanced in AGood neutrophils compared to HC. fMLF stimulated neutrophils from ASubopt but not AGood produced 50% of HC levels. fMLF induced MMP-9 was impaired in ASubopt and AGood compared to HC. fMLF stimulated CXCL8 but not MMP-9 was positively correlated with FEV1 and FEV1/FVC. ASubopt and AGood responded similarly to other stimuli. Conclusions. Circulating neutrophils are different in asthma; however, this is likely to be related to airflow limitation rather than asthma control
The magmatic system beneath the Tristan da Cunha Island: Insights from thermobarometry, melting models and geophysics
This study provides new insights on the conditions of melt generation and of magma transport and storage beneath Tristan da Cunha Island in the South Atlantic. Situated at the seaward end of the Walvis Ridge-guyot hotspot track, this island is related to the evolving magmatic system of the Tristan plume. Much is known about the geochemical and isotopic composition of the alkaline lavas on Tristan, but the pressure-temperature conditions of the hotspot magmas are under-explored. This contribution reports new data from a suite of 10 samples collected during a geologic-geophysical expedition in 2012. The focus of this study is on the least-evolved, phenocryst-rich basanite lavas but we also included a sample of trachyandesite lava erupted in 1961. Mineral-melt equilibrium thermobarometry uses the composition of olivine, clinopyroxene and plagioclase phenocrysts. In addition to bulk-rock data we also analysed olivine-hosted melt inclusions for the P-T calculations. The results for olivine-melt and clinopyroxene-melt calculations suggest crystallization conditions of around 1200-1250. °C and 0.8-1.3. GPa for the least-evolved magmas (ankaramitic basanites). Combined with seismological evidence for a Moho depth of about 19. km, these results imply magma storage and partial crystallization of Tristan magmas in the uppermost mantle and at Moho level. The trachyandesite yielded values of about 1000. °C and 0.2-0.3. GPa (6 to 10. km depth), indicating further crystallization within the crust.Constraints on the depth and degree of melting at the source of Tristan basanites were derived from REE inverse modelling using our new trace element data. The model predicts 5% melt generation from a melting column with its base at 80-100. km and a top at 60. km, which is consistent with the lithospheric thickness resulting from cooling models and seismological observations. The thermobarometry and melting models combined suggest a mantle potential temperature of about 1360. °C for the Tristan hotspot
Cultivating community economies: tools for building a liveable world
One chapter allowed - 18mth embargoAmid the failure of traditional politics and policies to address our fundamental challenges, an increasing number of thoughtful proposals and real-world models suggest new possibilities, this book convenes an essential conversation about ..
VLT FORS2 comparative transmission spectroscopy: Detection of Na in the atmosphere of WASP-39b from the ground
We present transmission spectroscopy of the warm Saturn-mass exoplanet WASP-39b made with the
Very Large Telescope FOcal Reducer and Spectrograph (FORS2) across the wavelength range 411–810 nm.
The transit depth is measured with a typical precision of 240 parts per million (ppm) in wavelength bins of 10 nm
on a V = 12.1 mag star. We detect the sodium absorption feature (3.2σ) and find evidence of potassium. The
ground-based transmission spectrum is consistent with Hubble Space Telescope (HST) optical spectroscopy,
supporting the interpretation that WASP-39b has a largely clear atmosphere. Our results demonstrate the great
potential of the recently upgraded FORS2 spectrograph for optical transmission spectroscopy, with which we
obtained HST-quality light curves from the ground
What are we fighting for? Ideological posturing and anarchist geographies
Recent debates in radical geography seem determined to be oppositional and in so doing simplify what is at stake. We need to celebrate and maintain the openness of geography to multiple perspectives while simultaneously developing more action-oriented, hopeful ways forward. Anarchist perspectives hold plenty of promise for radical geography, but only if we critically interrogate their principles and empirics
Discovery of mating in the major African livestock pathogen Trypanosoma congolense
The protozoan parasite, Trypanosoma congolense, is one of the most economically important pathogens of livestock in Africa and, through its impact on cattle health and productivity, has a significant effect on human health and well being. Despite the importance of this parasite our knowledge of some of the fundamental biological processes is limited. For example, it is unknown whether mating takes place. In this paper we have taken a population genetics based approach to address this question. The availability of genome sequence of the parasite allowed us to identify polymorphic microsatellite markers, which were used to genotype T. congolense isolates from livestock in a discrete geographical area of The Gambia. The data showed a high level of diversity with a large number of distinct genotypes, but a deficit in heterozygotes. Further analysis identified cryptic genetic subdivision into four sub-populations. In one of these, parasite genotypic diversity could only be explained by the occurrence of frequent mating in T. congolense. These data are completely inconsistent with previous suggestions that the parasite expands asexually in the absence of mating. The discovery of mating in this species of trypanosome has significant consequences for the spread of critical traits, such as drug resistance, as well as for fundamental aspects of the biology and epidemiology of this neglected but economically important pathogen
Expecting to lift a box together makes the load look lighter
The action abilities of an individual observer modulate his or her perception of spatial properties of the environment and of objects. The present study investigated how joint action abilities shape perception. Four experiments examined how the intention to lift an object with another individual affects perceived weight. In Experiments 1, 2a, and 2b, participants judged the perceived weight of boxes while expecting to lift them either alone or with a co-actor. In Experiment 3, the co-actor was healthy or injured. Participants intending to lift a box with a co-actor perceived the box as lighter than participants intending to lift the same box alone, provided that the co-actor appeared healthy and therefore capable of helping. These findings suggest that anticipated effort modulates the perception of object properties in the context of joint action. We discuss implications for the role of action prediction and action simulation processes in social interaction
Antagonism, accommodation and agonism in critical management studies: alternative organizations as allies
Critical Management Studies has long been engaged in discussions about the purpose of critique and the possibilities of engagement. A recent expression calls for Critical Management Studies to moderate its ‘negative’ critique of management and instead use words like care, engagement and affirmation in order to enable ‘progressive’ engagement with managers. This ‘performative turn’ has been poorly received by some who see it as a dilution of radical intent. We argue for a middle ground between the antagonistic versions of Critical Management Studies that appear to want to oppose management, and ‘performative’ scholars who appear to accommodate with managerialism. We do this by planting the debate firmly within an empirical setting and a crisis that the first author experienced as a ‘critical scholar’ when conducting an ethnography at a sustainable financial services firm. In order to do this, we explore Chantal Mouffe’s concept of agonism to establish a particular mode of political engagement that acknowledges a space between being ‘for’ and being ‘against’. We conclude by suggesting that the exploration of alternative forms of organization and management, themselves already involved in struggle against a hegemonic present, should be the proper task of a discipline that wishes to engage with the present and remain ‘critical
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