282 research outputs found
Protecting the Health of First Nation Personnel at Contaminated Sites: A Case Study of Mid-Canada Radar Line Site 050 in Northern Canada
Recently, First Nation (FN) organizations have entered into agreements with federal and provincial government representatives to remediate radar-line sites in Ontario. These agreements stipulated that FN people would take part in the site delineation and remediation process to gain job experience and economic benefits. One important aspect of the process was protecting FN personnel from contaminant exposure and thus, from potential negative health outcomes associated with the cleanup work itself. In this paper, we describe the safety precautions used by FN workers preparing Mid-Canada Radar Line (MCRL) Site 050 for Phase 2 of the delineation process and the health monitoring protocol that was tested. We measured concentrations of total polychlorinated biphenyls (PCBs as Aroclor 1260), 14 individual PCB congeners, p,pâ-DDT, p,pâ-DDE, nine other organochlorine pesticides, and lead in the blood of Fort Albany FN workers before they started work at Site 050 and approximately a week before they completed their three-month work period in the contaminated zone. No significant differences were found in the paired samples. These results indicate that the safety precautions taken were adequate for the work and the site in question. The monitoring protocol discussed here may be used as a template and modified to meet the specific needs of other projects. The results of this study are important because other Aboriginal groups have entered or will be entering into agreements with government organizations for the remediation of other MCRL sites in Ontario and across Canada.Les stations de ligne radar dĂ©saffectĂ©es situĂ©es tant dans lâArctique que dans le Subarctique canadiens seraient des sources ponctuelles de contamination. Des organismes des PremiĂšres nations ont participĂ© derniĂšrement, avec des reprĂ©sentants des gouvernements fĂ©dĂ©ral et provinciaux, Ă des accords visant lâassainissement des stations de ligne radar en Ontario. Ces accords stipulaient que des membres des PremiĂšres nations prendraient part Ă la dĂ©limitation des sites et au processus dâassainissement afin dâacquĂ©rir de lâexpĂ©rience de travail et de profiter des retombĂ©es Ă©conomiques. Un volet important de ce processus visait Ă protĂ©ger le personnel autochtone de lâexposition aux contaminants et donc, dâeffets potentiels nĂ©gatifs pour la santĂ© associĂ©s aux opĂ©rations de nettoyage mĂȘmes. Dans cet article, on dĂ©crit les mesures de sĂ©curitĂ© utilisĂ©es par les travailleurs autochtones oeuvrant sur le site 050 de la ligne radar Mid-Canada durant la phase 2 du processus de dĂ©limitation, ainsi que le protocole de contrĂŽle de la santĂ© mis alors Ă lâessai. On a mesurĂ© les concentrations de lâaccumulation de diphĂ©nyles polychlorĂ©s (PCB comme lâArochlore 1260), de 14 congĂ©nĂšres de PCB, de p,pâ-DDT, de p,pâ-DDE, de neuf autres pesticides organochlorĂ©s ainsi que de plomb dans le sang des travailleurs autochtones de Fort Albany avant quâils commencent Ă travailler au site 050 et une semaine environ avant quâils terminent leur pĂ©riode de travail de trois mois dans la zone contaminĂ©e. On nâa pas trouvĂ© de diffĂ©rences significatives entre les Ă©chantillons appariĂ©s. Ces rĂ©sultats rĂ©vĂšlent que les mesures de sĂ©curitĂ© prises Ă©taient adĂ©quates pour le travail et le site en question. Le protocole de contrĂŽle discutĂ© ici pourrait servir de modĂšle et ĂȘtre adaptĂ© pour rĂ©pondre aux critĂšres spĂ©cifiques dâautres projets. Les rĂ©sultats de cette Ă©tude sont importants car dâautres groupes autochtones participent actuellement ou vont participer Ă des accords avec des agences gouvernementales visant lâassainissement dâautres sites de la ligne radar Mid-Canada en Ontario et Ă travers le Canada
Thermal radiation processes
We discuss the different physical processes that are important to understand
the thermal X-ray emission and absorption spectra of the diffuse gas in
clusters of galaxies and the warm-hot intergalactic medium. The ionisation
balance, line and continuum emission and absorption properties are reviewed and
several practical examples are given that illustrate the most important
diagnostic features in the X-ray spectra.Comment: 37 pages, 16 figures, accepted for publication in Space Science
Reviews, special issue "Clusters of galaxies: beyond the thermal view",
Editor J.S. Kaastra, Chapter 9; work done by an international team at the
International Space Science Institute (ISSI), Bern, organised by J.S.
Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke
Immune Antibodies and Helminth Products Drive CXCR2-Dependent Macrophage-Myofibroblast Crosstalk to Promote Intestinal Repair.
Helminth parasites can cause considerable damage when migrating through host tissues, thus making rapid tissue repair imperative to prevent bleeding and bacterial dissemination particularly during enteric infection. However, how protective type 2 responses targeted against these tissue-disruptive multicellular parasites might contribute to homeostatic wound healing in the intestine has remained unclear. Here, we observed that mice lacking antibodies (Aid-/-) or activating Fc receptors (Fcrg-/-) displayed impaired intestinal repair following infection with the murine helminth Heligmosomoides polygyrus bakeri (Hpb), whilst transfer of immune serum could partially restore chemokine production and rescue wound healing in Aid-/- mice. Impaired healing was associated with a reduced expression of CXCR2 ligands (CXCL2/3) by macrophages (MΊ) and myofibroblasts (MF) within intestinal lesions. Whilst antibodies and helminths together triggered CXCL2 production by MΊ in vitro via surface FcR engagement, chemokine secretion by intestinal MF was elicited by helminths directly via Fcrg-chain/dectin2 signaling. Blockade of CXCR2 during Hpb challenge infection reproduced the delayed wound repair observed in helminth infected Aid-/- and Fcrg-/- mice. Finally, conditioned media from human MΊ stimulated with infective larvae of the helminth Ascaris suum together with immune serum, promoted CXCR2-dependent scratch wound closure by human MF in vitro. Collectively our findings suggest that helminths and antibodies instruct a chemokine driven MΊ-MF crosstalk to promote intestinal repair, a capacity that may be harnessed in clinical settings of impaired wound healing
Metabolite changes in blood predict the onset of tuberculosis
Immunogenetics and cellular immunology of bacterial infectious disease
Monitoring anti-tuberculosis treatment response using analysis of whole blood Mycobacterium tuberculosis specific T cell activation and functional markers
Background: Blood-based biomarkers have been proposed as an alternative to current sputum-based treatment monitoring methods in active tuberculosis (ATB). The aim of this study was to validate previously described phenotypic, activation, and cytokine markers of treatment response in a West African cohort.
Methods: Whole blood immune responses to Mycobacterium tuberculosis ESAT-6/CFP-10 (EC) and purified protein derivative (PPD) were measured in twenty adults at baseline and after 2 months of standard TB treatment. Patients were classified as fast or slow responders based on a negative or positive sputum culture result at 2 months, respectively. Cellular expression of activation markers (CD38, HLA-DR), memory markers (CD27), and functional intracellular cytokine and proliferation (IFN-γ, Ki-67, TNF-α) markers were measured using multi-color flow cytometry.
Results: There was a significant increase in the proportion of CD4+CD27+ cells expressing CD38 and HLA-DR following EC stimulation at 2 months compared to baseline (p = 0.0328 and p = 0.0400, respectively). Following PPD stimulation, slow treatment responders had a significantly higher proportion of CD8+CD27âIFN-Îł+ (p = 0.0105) and CD4+CD27+HLA-DR+CD38+ (p = 0.0077) T cells than fast responders at baseline. Receiver operating curve analysis of these subsets resulted in 80% sensitivity and 70 and 100% specificity, respectively (AUC of 0.82, p = 0.0156 and 0.84, p = 0.0102).
Conclusion: Our pilot data show reductions in expression of T cell activation markers were seen with treatment, but this was not associated with fast or slow sputum conversion at 2 months. However, baseline proportions of activated T cell subsets are potentially predictive of the subsequent speed of response to treatment
Simulation techniques for cosmological simulations
Modern cosmological observations allow us to study in great detail the
evolution and history of the large scale structure hierarchy. The fundamental
problem of accurate constraints on the cosmological parameters, within a given
cosmological model, requires precise modelling of the observed structure. In
this paper we briefly review the current most effective techniques of large
scale structure simulations, emphasising both their advantages and
shortcomings. Starting with basics of the direct N-body simulations appropriate
to modelling cold dark matter evolution, we then discuss the direct-sum
technique GRAPE, particle-mesh (PM) and hybrid methods, combining the PM and
the tree algorithms. Simulations of baryonic matter in the Universe often use
hydrodynamic codes based on both particle methods that discretise mass, and
grid-based methods. We briefly describe Eulerian grid methods, and also some
variants of Lagrangian smoothed particle hydrodynamics (SPH) methods.Comment: 42 pages, 16 figures, accepted for publication in Space Science
Reviews, special issue "Clusters of galaxies: beyond the thermal view",
Editor J.S. Kaastra, Chapter 12; work done by an international team at the
International Space Science Institute (ISSI), Bern, organised by J.S.
Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke
Electromagnetic corrections in eta --> 3 pi decays
We re-evaluate the electromagnetic corrections to eta --> 3 pi decays at
next-to-leading order in the chiral expansion, arguing that effects of order
e^2(m_u-m_d) disregarded so far are not negligible compared to other
contributions of order e^2 times a light quark mass. Despite the appearance of
the Coulomb pole in eta --> pi+ pi- pi0 and cusps in eta --> 3 pi0, the overall
corrections remain small.Comment: 21 pages, 11 figures; references updated, version published in EPJ
The chemical enrichment of the ICM from hydrodynamical simulations
The study of the metal enrichment of the intra-cluster and inter-galactic
media (ICM and IGM) represents a direct means to reconstruct the past history
of star formation, the role of feedback processes and the gas-dynamical
processes which determine the evolution of the cosmic baryons. In this paper we
review the approaches that have been followed so far to model the enrichment of
the ICM in a cosmological context. While our presentation will be focused on
the role played by hydrodynamical simulations, we will also discuss other
approaches based on semi-analytical models of galaxy formation, also critically
discussing pros and cons of the different methods. We will first review the
concept of the model of chemical evolution to be implemented in any
chemo-dynamical description. We will emphasise how the predictions of this
model critically depend on the choice of the stellar initial mass function, on
the stellar life-times and on the stellar yields. We will then overview the
comparisons presented so far between X-ray observations of the ICM enrichment
and model predictions. We will show how the most recent chemo-dynamical models
are able to capture the basic features of the observed metal content of the ICM
and its evolution. We will conclude by highlighting the open questions in this
study and the direction of improvements for cosmological chemo-dynamical models
of the next generation.Comment: 25 pages, 11 figures, accepted for publication in Space Science
Reviews, special issue "Clusters of galaxies: beyond the thermal view",
Editor J.S. Kaastra, Chapter 18; work done by an international team at the
International Space Science Institute (ISSI), Bern, organised by J.S.
Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeke
Anomalous Pseudoscalar-Photon Vertex In and Out of Equilibrium
The anomalous pseudoscalar-photon vertex is studied in real time in and out
of equilibrium in a constituent quark model. The goal is to understand the
in-medium modifications of this vertex, exploring the possibility of enhanced
isospin breaking by electromagnetic effects as well as the formation of neutral
pion condensates in a rapid chiral phase transition in peripheral,
ultrarelativistic heavy-ion collisions. In equilibrium the effective vertex is
afflicted by infrared and collinear singularities that require hard thermal
loop (HTL) and width corrections of the quark propagator. The resummed
effective equilibrium vertex vanishes near the chiral transition in the chiral
limit. In a strongly out of equilibrium chiral phase transition we find that
the chiral condensate drastically modifies the quark propagators and the
effective vertex. The ensuing dynamics for the neutral pion results in a
potential enhancement of isospin breaking and the formation of
condensates. While the anomaly equation and the axial Ward identity are not
modified by the medium in or out of equilibrium, the effective real-time
pseudoscalar-photon vertex is sensitive to low energy physics.Comment: Revised version to appear in Phys. Rev. D. 42 pages, 4 figures, uses
Revte
Daratumumab, lenalidomide, and dexamethasone in relapsed/refractory myeloma: a cytogenetic subgroup analysis of POLLUX
High cytogenetic risk abnormalities confer poor outcomes in multiple myeloma patients. In POLLUX, daratumumab/lenalidomide/dexamethasone (D-Rd) demonstrated significant clinical benefit versus lenalidomide/dexamethasone (Rd) in relapsed/refractory multiple myeloma (RRMM) patients. We report an updated subgroup analysis of POLLUX based on cytogenetic risk. The cytogenetic risk was determined using fluorescence in situ hybridization/karyotyping; patients with high cytogenetic risk had t(4;14), t(14;16), or del17p abnormalities. Minimal residual disease (MRD; 10â5) was assessed via the clonoSEQÂź assay V2.0. 569 patients were randomized (D-Rd, nâ=â286; Rd, nâ=â283); 35 (12%) patients per group had high cytogenetic risk. After a median follow-up of 44.3 months, D-Rd prolonged progression-free survival (PFS) versus Rd in standard cytogenetic risk (median: not estimable vs 18.6 months; hazard ratio [HR], 0.43; Pâ<â0.0001) and high cytogenetic risk (median: 26.8 vs 8.3 months; HR, 0.34; Pâ=â0.0035) patients. Responses with D-Rd were deep, including higher MRD negativity and sustained MRD-negativity rates versus Rd, regardless of cytogenetic risk. PFS on subsequent line of therapy was improved with D-Rd versus Rd in both cytogenetic risk subgroups. The safety profile of D-Rd by cytogenetic risk was consistent with the overall population. These findings demonstrate the improved efficacy of daratumumab plus standard of care versus standard of care in RRMM, regardless of cytogenetic risk
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