The lineage relationships and fate of human dendritic cells (DCs) have significance for a number of diseases including HIV where both blood and tissue DCs may be infected. We used gene expression ...profiling of human monocyte and DC subpopulations sorted directly from blood and skin to define the lineage relationships. We also compared these with monocyte-derived DCs (MDDCs) and MUTZ3 Langerhans cells (LCs) to investigate their relevance as model skin DCs. Hierarchical clustering analysis showed that myeloid DCs clustered according to anatomical origin rather than putative lineage. Plasmacytoid DCs formed the most discrete cluster, but ex vivo myeloid cells formed separate clusters of cells both in blood and in skin. Separate and specific DC populations could be determined within skin, and the proportion of CD14(+) dermal DCs (DDCs) was reduced and CD1a(+) DDCs increased during culture, suggesting conversion to CD1a(+)-expressing cells in situ. This is consistent with origin of the CD1a(+) DDCs from a local precursor rather than directly from circulating blood DCs or monocyte precursors. Consistent with their use as model skin DCs, the in vitro-derived MDDC and MUTZ3 LC populations grouped within the skin DC cluster. MDDCs clustered most closely to CD14(+) DDCs; furthermore, common unique patterns of C-type lectin receptor expression were identified between these two cell types. MUTZ3 LCs, however, did not cluster closely with ex vivo-derived LCs. We identified differential expression of novel genes in monocyte and DC subsets including genes related to DC surface receptors (including C-type lectin receptors, TLRs, and galectins).
Understanding teachers’ experiences as they lived them and as they told them is important for conceptualizing a well-rounded view of the state of science education and the role teachers play in it. ...Journey mapping, a way of visualizing one’s processes and experiences as they progress towards a goal, is a tool with the potential to capture teachers’ lived experiences. The purpose of this study was to explore elementary teachers’ lived experiences as they work to provide science and engineering learning experiences for their students. This paper highlights the use of STEM journey mapping as a way of exploring teachers’ lived experiences in their day-to-day practice. This study features the STEM journey map and subsequent narrative of a fourth-grade teacher, Elliot. The data analysis supported the argument that journey mapping was a powerful tool for exploring teachers’ lived experiences.
The experimental and numerical modeling of cold forging operations conducted on commercial Al alloys requires a precise knowledge of the functional dependence of both flow stress and work-hardening ...rate on microstructure and deformation conditions. In order to contribute to the improvement of the finite element computer modeling of forming operations conducted on Al alloys, under cold-warm working conditions, an original and rational constitutive description, able to predict accurately both the flow stress and work-hardening rate of an AA6082-T6 Al alloy is proposed. The constitutive formulation has been developed on the basis of the Mechanical Threshold Stress (MTS) model and its applicability is limited to the deformation of the material under cold-warm working conditions, that is to say, in the temperature range of 298–423 K. A novel differential equation for the description of the continuous change in the work-hardening rate of the alloy has been developed, which allows the prediction of the changes in flow stress and work-hardening rate during deformation either under constant and variable temperature and strain rate conditions. The validation of the developed constitutive description has been accomplished by its implementation into a finite element (FE) model for the accurate prediction of the change in some local contact parameters, such as contact pressure, sliding velocity and interface temperature, during the friction test employed in the evaluation of friction conditions in metalworking, known as the Upsetting Sliding Test (UST).
•An original and rational constitutive description for the 6082-T6 Al alloy is proposed.•A novel differential equation for describing the change in the work-hardening rate of the alloy has been developed.•The model developed is able to describe the changes in flow stress under transient deformation conditions.•The model has been validated by means of experiments and FEM analysis of the upsetting sliding test.
The Microchannel X-ray Telescope (MXT) is an innovative compact X-ray instrument on board the SVOM astronomical mission dedicated to the study of transient phenomena such as gamma-ray bursts. During ...3 weeks, we have tested the MXT flight model at the Panter X-ray test facility under the nominal temperature and vacuum conditions that MXT will undergo in-flight. We collected data at series of characteristic energies probing the entire MXT energy range, from 0.28 keV up to 9 keV, for multiple source positions with the center of the point spread function (PSF) inside and outside the detector field of view (FOV). We stacked the data of the positions with the PSF outside the FOV to obtain a uniformly illuminated matrix and reduced all data sets using a dedicated pipeline. We determined the best spectral performance of MXT using an optimized data processing, especially for the energy calibration and the charge sharing effect induced by the pixel low energy thresholding. Our results demonstrate that MXT is compliant with the instrument requirement regarding the energy resolution (< 80 eV at 1.5 keV), the low and high energy threshold, and the accuracy of the energy calibration (± 20 eV). We also determined the charge transfer inefficiency (
∼
1
0
−
5
) of the detector and modeled its evolution with energy prior to the irradiation that MXT will undergo during its in-orbit lifetime. Finally, we measured the relation of the energy resolution as function of the photon energy. We determined an equivalent noise charge of
4.9
±
0.2
e
rms
−
for the MXT detection chain and a Fano factor of 0.131 ± 0.003 in silicon at 208 K, in agreement with previous works. This campaign confirmed the promising scientific performance that MXT will be able to deliver during the mission lifetime.
HIV-1 is taken up by immature monocyte derived dendritic cells (iMDDCs) into tetraspanin rich caves from which the virus can either be transferred to T lymphocytes or enter into endosomes resulting ...in degradation. HIV-1 binding and fusion with the DC membrane results in low level de novo infection that can also be transferred to T lymphocytes at a later stage. We have previously reported that HIV-1 can induce partial maturation of iMDDCs at both stages of trafficking. Here we show that CD45⁺ microvesicles (MV) which contaminate purified HIV-1 inocula due to similar size and density, affect DC maturation, de novo HIV-1 infection and transfer to T lymphocytes. Comparing iMDDCs infected with CD45-depleted HIV-1BaL or matched non-depleted preparations, the presence of CD45⁺ MVs was shown to enhance DC maturation and ICAM-1 (CD54) expression, which is involved in DC∶T lymphocyte interactions, while restricting HIV-1 infection of MDDCs. Furthermore, in the DC culture HIV-1 infected (p24⁺) MDDCs were more mature than bystander cells. Depletion of MVs from the HIV-1 inoculum markedly inhibited DC∶T lymphocyte clustering and the induction of alloproliferation as well as limiting HIV-1 transfer from DCs to T lymphocytes. The effects of MV depletion on these functions were reversed by the re-addition of purified MVs from activated but not non-activated SUPT1.CCR5-CL.30 or primary T cells. Analysis of the protein complement of these MVs and of these HIV-1 inocula before and after MV depletion showed that Heat Shock Proteins (HSPs) and nef were the likely DC maturation candidates. Recombinant HSP90α and β and nef all induced DC maturation and ICAM-1 expression, greater when combined. These results suggest that MVs contaminating HIV-1 released from infected T lymphocytes may be biologically important, especially in enhancing T cell activation, during uptake by DCs in vitro and in vivo, particularly as MVs have been detected in the circulation of HIV-1 infected subjects.
The Microchannel X-ray Telescope (MXT) will be the first focusing X-ray telescope based on a narrow field “Lobster-Eye” optical design to be flown on a satellite, namely the Sino-French mission SVOM. ...SVOM will be dedicated to the study of Gamma-Ray Bursts and more generally time-domain astrophysics. The MXT telescope is a compact (focal length
∼
1.15 m) and light (< 42 kg) instrument, sensitive in the 0.2–10 keV energy range. It is composed of an optical system, based on micro-pore optics (MPOs) of 40
μ
m pore size, coupled to a low-noise pnCDD X-ray detector. In this paper we describe the expected scientific performance of the MXT telescope, based on the End-to-End calibration campaign performed in fall 2021, before the integration of the SVOM payload on the satellite.
The Translatability of Experience Mercier, Lucie K.
Critical times (Berkeley, Calif.),
04/2023, Letnik:
6, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Fanon considered that colonial alienation produced multiple forms of relational pathologies, many of which expressed themselves in and through blockages in communication rather than through explicit ...conflict. Exposing the role of language as a vector of racial violence and colonial oppression, Fanon also presented it as a potentially revolutionary medium of decolonization. The article has two aims: firstly, to give an account of Fanon's ongoing concern with language, in part by underscoring three very different influences in Fanon's expansive conception of its role—those of Aimé Césaire, Maurice Merleau-Ponty, and François Tosquelles. Secondly, the article aims to rearticulate the function of language in Fanon's theory of colonial disalienation by drawing on a specific trajectory in his clinico-political thought: from diagnoses of untranslatability or incommunicability to analyses of decolonization as the radical transformation of the subject's experience of language.
As a result of the low yield of cartilage from primary patient harvests and a high demand for autologous cartilage for reconstructive surgery and structural repair, primary explant cartilage must be ...augmented by tissue engineering techniques. In this study, chondrocytes seeded on PLLA/PGA scaffolds in static culture and a direct perfusion bioreactor were biochemically and histologically analyzed to determine the effects of fluid flow and media pH on matrix assembly. A gradual media pH change was maintained in the bioreactor within 7.4−6.96 over 2 weeks compared to a more rapid decrease from 7.4 to 6.58 in static culture over 3 days. Seeded scaffolds subjected to 1 μm/s flow demonstrated a 118% increase (p < 0.05) in DNA content, a 184% increase (p < 0.05) in GAG content, and a 155% (p< 0.05) increase in hydroxyproline content compared to static culture. Distinct differences were noted in tissue morphology, including more intense staining for proteoglycans by safranin‐O and alignment of cells in the direction of media flow. Culture of chondrocyte seeded matrices thus offers the possibility of rapid in vitro expansion of donor cartilage for the repair of structural defects, tracheal injury, and vascularized tissue damage.
Efavirenz (EFV) causes neuropsychiatric side-effects and an unfavourable blood lipid profile. We investigated the effect of replacing EFV with etravirine (ETR) on patient preference, sleep, anxiety ...and lipid levels.
Study participants did not complain of side-effects, had tolerated EFV for at least 3 months, with less than 50 copies/ml HIV-RNA. After randomization, the ETR-first group started with ETR (400 mg daily) DOSAGE ERROR CORRECTED with EFV-placebo and the EFV-first group with EFV with ETR-placebo. After 6 weeks, both groups switched to the alternate regimen. Nucleoside reverse transcriptase inhibitors were continued without any change. The primary end point was patient preference for the first or the second regimen, assessed after 12 weeks.
Fifty-eight patients were enrolled with a median CD4 cell count of 589 cells/μl and the duration of previous EFV therapy was 3.9 years. Fifty-five patients completed the study. When asked about treatment preference after 12 weeks, 16 preferred EFV and 22 preferred ETR, whereas 17 did not express a preference (P = NS). Patients who continued EFV during the first phase of the trial preferred EFV (15/21, 71%), whereas patients who started with ETR were more likely to prefer ETR (n = 16/17, 94%). This order effect was strongly significant (P < 0.0001). Quality of sleep, depression, anxiety and stress scores did not differ significantly between groups. Median plasma cholesterol levels decreased by 0.7 mmol (29 mg/100 ml) after replacing EFV with ETR (P < 0.002).
After substitution of EFV by ETR, patients did not express a significant preference for ETR. There was no measurable effect on neuropsychiatric symptoms and sleep. Cholesterol decreased.
Purpose:
Advanced stereotactic radiotherapy (SRT) treatments require accurate dose calculation for treatment planning especially for treatment sites involving heterogeneous patient anatomy. The ...purpose of this study was to evaluate the accuracy of dose calculation algorithms, Raytracing and Monte Carlo (MC), implemented in the MultiPlan treatment planning system (TPS) in presence of heterogeneities.
Methods:
First, the LINAC of a CyberKnife radiotherapy facility was modeled with the PENELOPE MC code. A protocol for the measurement of dose distributions with EBT3 films was established and validated thanks to comparison between experimental dose distributions and calculated dose distributions obtained with MultiPlan Raytracing and MC algorithms as well as with the PENELOPE MC model for treatments planned with the homogenous Easycube phantom. Finally, bones and lungs inserts were used to set up a heterogeneous Easycube phantom. Treatment plans with the 10, 7.5 or the 5 mm field sizes were generated in Multiplan TPS with different tumor localizations (in the lung and at the lung/bone/soft tissue interface). Experimental dose distributions were compared to the PENELOPE MC and Multiplan calculations using the gamma index method.
Results:
Regarding the experiment in the homogenous phantom, 100% of the points passed for the 3%/3mm tolerance criteria. These criteria include the global error of the method (CT‐scan resolution, EBT3 dosimetry, LINAC positionning …), and were used afterwards to estimate the accuracy of the MultiPlan algorithms in heterogeneous media. Comparison of the dose distributions obtained in the heterogeneous phantom is in progress.
Conclusion:
This work has led to the development of numerical and experimental dosimetric tools for small beam dosimetry. Raytracing and MC algorithms implemented in MultiPlan TPS were evaluated in heterogeneous media.
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