La pancarte de consignation : un artefact cognitif pour l'intelligibilité mutuelle dans une industrie à risques

International audienceJoint collective activity contributes to the reliability of High-Risk Organizations and relies on a set of coordinative practices. Such practices are documented in this paper from two perspectives: the production of mutual intelligibility and the role played by cognitive artifacts in this production. The empirical material is provided by a workplace study undertaken in the context of a design project that aims at improving the clearance and tagging process in a high-risk industry. Findings illustrate the role played by cognitive artifacts in the clearance and tagging process, focusing on the coordinated use of a particular artifact: the clearance tag. A detailed analysis of an interaction sequence reveals how this artifact, which was designed to support coordination in a specific way, may fail to support the production of mutual intelligibility in asynchronous collaboration.Dans sa contribution à la construction de la fiabilité des systèmes à risques, l'activité conjointe mobilise de manière centrale des mécanismes de coordination. Cette communication documente ces mécanismes, du point de vue de la production d'intelligibilité mutuelle et de celui du rôle joué par les artefacts cognitifs dans cette production. Elle se fonde sur une étude menée dans le cadre d'un projet de modification du dispositif de consignation dans une industrie de process. Les résultats illustrent le rôle des artefacts cognitifs dans le processus de consignation par une analyse détaillée de l'usage coordonné d'un artefact : la pancarte de consignation. L'analyse d'un épisode d'activité met en évidence les limites intrinsèques de cet artefact, conçu pour assurer une fonction précise dans la coordination des opérateurs, en termes d'assistance à la production d'intelligibilité mutuelle dans une interaction asynchrone

Los efectos del work engagement y la auto-efi cacia en la iniciativa personal y el desempeño.

Background: Two popular concepts, work engagement and personal initiative, are different but related constructs. This study is based on and extends the Frese and Fay (2001) model of personal initiative (PI) by including work engagement (WE) and self-effi cacy as antecedents of PI, and performance as a consequence. Method: Two studies (study 1, with a cross-sectional design using N = 396 participants from 22 organizations, and study 2, with a longitudinal design conducted in two waves with N = 118 participants from 15 organizations) test the hypotheses. Results: Structural equation modeling and the PROCESS SPSS Macro were used to test the hypothesized mediating role of personal initiative in work engagement and performance, and the results show the indirect effect of WE on performance through PI. Conclusions: The results of these two studies confi rmed our hypotheses: WE and self-effi cacy lead to higher PI, which, in turn, leads to higher performance. In addition to considering WE as an antecedent of PI, the results lead to considering PI as an antecedent of performance.Los efectos del work engagement y la auto-efi cacia en la iniciativa personal y el desempeño. Antecedentes: los conceptos work engagement e iniciativa personal están relacionados pero son conceptos diferentes. Este trabajo se basa en el modelo de la iniciativa personal de Frese y Fay (2001) y lo amplía incluyendo el work engagement como antecedente de la iniciativa personal, junto con la autoefi cacia y el desempeño como resultado. Método: se realizaron dos estudios (estudio 1 con un diseño transversal N = 396 participantes de 22 organizaciones y estudio 2 con un diseño longitudinal con dos tiempos y N = 118 participantes de 15 organizaciones) para contrastar las hipótesis. Resultados: se utilizaron modelos de ecuaciones estructurales y el Macro de SPSS Process para contrastar el rol mediador de la iniciativa perosnal entre el work engagement y el desempeño, mostrando los resultados los efectos indirectos del work engagement sobre el desempeño a través de la iniciativa personal. Conclusión: los resultados de los dos estudios confi rman nuestras hipótesis. Work engagment y autoefi cacia llevan a una mayor iniciativa personal, que implica una mejora del desempeño. Junto a considerar el work engagment un antecedente de la iniciativa personal, los resultados permiten considerar a la iniciativa un antecedente del desempeño

Radial elasticity of multi-walled carbon nanotubes

We report an experimental and a theoretical study of the radial elasticity of multi-walled carbon nanotubes as a function of external radius. We use atomic force microscopy and apply small indentation amplitudes in order to stay in the linear elasticity regime. The number of layers for a given tube radius is inferred from transmission electron microscopy, revealing constant ratios of external to internal radii. This enables a comparison with molecular dynamics results, which also shed some light onto the applicability of Hertz theory in this context. Using this theory, we find a radial Young modulus strongly decreasing with increasing radius and reaching an asymptotic value of 30 +/- 10 GPa.Comment: 5 pages, 3 figure

IS1245 genotypic analysis of Mycobacterium avium isolates from patients in Brazil

AbstractObjective: Disseminated Mycobacterium avium infection is an emerging opportunistic disease among patients with acquired immunodeficiency syndrome (AIDS) in Brazil. The mode of transmission of M. avium in a developing country setting needs to be better characterized.Methods: Mycobacterium avium strain collections in São Paulo and Rio de Janeiro were analyzed according to the strains' IS1245 DNA gel electrophoretic migration patterns. Medical records of the patients from whom M. avium isolates were available were reviewed, and their demographic characteristics were stratified according to the isolates' IS1245 DNA fingerprint patterns.Results: Of 105 patients, 33 (31 %) with M. avium isolated between 1990 and 1994 had strains having IS1245 patterns identical in patterns seen in isolates from two or more patients (designated as cluster pattern strains). Cluster pattern strains were isolated from 21 (39%) of 54 patients with disseminated infection (defined as infection due to M. avium isolated from a sterile site in an adult patient). Six of the cluster pattern strains were isolated only from sterile sites. In São Paulo, cluster pattern strains were significantly more likely to be isolated from patients with disseminated disease.Conclusions: These preliminary observations suggest that in large cities of Brazil, a high proportion (at least 39%) of disseminated M. avium infections in patients with AIDS results from a recent transmission. Some strains of M. avium may be more likely to cause disseminated disease than others after an infection

Detecting deformation asymmetries on multiple meridians in an ex vivo keratoconic eye model

Purpose : Ocular biomechanical simulations show that air-puff induced corneal deformation imaging (APCDI) can reveal pathological asymmetric responses, as in eccentric keratoconus. Such asymmetries often go undetected when monitoring deformation on only one meridian (Birkenfeld et al., IOVS, 2019), as is the case with commercial instruments. We present a novel custom optical coherence tomography (OCT) system coupled with an air-puff module capable of detecting deformation asymmetries on multiple meridians in a keratoconic-mimicking ex vivo porcine eye model. Methods : Corneal deformation was induced by a piston-based air-puff module colinearly coupled to a custom OCT system. The puff module provided an air-puff FWHM duration of ~11 ms, reaching a maximum pressure on the corneal apex of ~13 kPa. Our OCT system used a 200 kHz 1300 nm VCSEL swept source, with an axial range of 26 mm. A freshly enucleated porcine eye globe was treated with a cross-linking (CXL) protocol with Rose Bengal (RB) photosensitizer and Green light irradiation (0.25 W/cm2, 2x200 s) of only the lower half of the cornea. We performed OCT APCDI measurements under controlled intraocular pressure (IOP, 15-30 mmHg) after application of RB (=baseline, BSL) and after partial CXL. We quantified the displaced area (DA) between the undeformed and deformed anterior cornea positions and asymmetry in displaced area (ADA), i.e. the difference between the nasal/temporal (or superior/inferior) DA referenced to the undeformed corneal apex. Results : We implemented a cross-meridian scan pattern over a lateral range of 15 mm sampled with 64 points at a repetition frequency of 1 kHz. For the BSL case, we validated the system by verifying the reduction of DA, from a maximum of ~4.3 to 1.8 mm2, with increasing IOP, from 15 to 30 mmHg. ADA was limited to below 0.2 mm2 in all cases for both meridians. For the partial CXL case and an IOP of 15 mm Hg, the ADA peaked at 0.5 mm2 for the vertical meridian, while it was below 0.2 mm2 at all times for the horizontal meridian. Conclusions : We acquired corneal deformation images with a cross-meridian scan pattern over a field of view of 15 mm at unprecedented scan rates. In keratoconus-mimicking cases, we detected deformation asymmetries up to 0.5 mm2, otherwise missed on a single meridian, that will substantially aid in corneal biomechanics diagnostics and pathology screening

Early alveolar macrophage response and IL-1R-dependent T cell priming determine transmissibility of Mycobacterium tuberculosis strains

Funding Information: The work was funded by the National Institute of Allergy and Infectious Diseases, National Institutes of Health grants U19AI111276 and U01AI065663 to R.R.R., R.D., J.J.E. and P.S., and NIAID training grant T32AI125185 to A.L. The study sponsors were not involved in the study design, in the collection, analysis, and interpretation of data; in the writing of the manuscript; or in the decision to submit the manuscript for publication. Publisher Copyright: © 2022, The Author(s).Mechanisms underlying variability in transmission of Mycobacterium tuberculosis strains remain undefined. By characterizing high and low transmission strains of M.tuberculosis in mice, we show here that high transmission M.tuberculosis strain induce rapid IL-1R-dependent alveolar macrophage migration from the alveolar space into the interstitium and that this action is key to subsequent temporal events of early dissemination of bacteria to the lymph nodes, Th1 priming, granulomatous response and bacterial control. In contrast, IL-1R-dependent alveolar macrophage migration and early dissemination of bacteria to lymph nodes is significantly impeded in infection with low transmission M.tuberculosis strain; these events promote the development of Th17 immunity, fostering neutrophilic inflammation and increased bacterial replication. Our results suggest that by inducing granulomas with the potential to develop into cavitary lesions that aids bacterial escape into the airways, high transmission M.tuberculosis strain is poised for greater transmissibility. These findings implicate bacterial heterogeneity as an important modifier of TB disease manifestations and transmission.publishersversionpublishe

Membros familiares e profissionais de saúde na supervisão do tratamento da tuberculose

OBJETIVO: Comparar los resultados de cura por tuberculosis entre pacientes supervisados por ele miembro familiar y por el profesional de salud. MÉTODOS: Estudio de cohorte prospectivo de 171 pacientes de Vitória, sureste de Brasil, en el período de 2004 a 2007. Cada paciente fue acompañado por seis meses hasta la finalización del tratamiento. De los pacientes estudiados, 59 pacientes tratados eran supervisados por un miembro familiar y 112 por los profesionales de salud. Fueron evaluados datos sociodemográficos y clínicos de los pacientes. Diferencias entre los grupos de estudio fueron evaluadas utilizando la prueba Chi-cuadrado o prueba t de Student al nivel de significancia de 5%. RESULTADOS: La mayoría de los sujetos de estudio presentaron bacioscopia positiva y cultivo confirmado para tuberculosis. Dos pacientes tenían serología positiva para HIV. Un número mayor de pacientes en el grupo supervisado por profesionales de salud no eran alfabetizados, comparado con aquellos pacientes del grupo supervisado por miembros familiares (p=0,01). Todos los pacientes supervisados por un familiar fueron curados, frente a 90% de los pacientes supervisados por los profesionales de salud (p=0,024). CONCLUSIONES: El éxito del tratamiento de tuberculosis fue mayor cuando se supervisó por un familiar.OBJETIVO: Comparar os resultados de cura por tuberculose entre pacientes supervisionados pelo membro familiar e pelo profissional de saúde. MÉTODOS: Estudo de coorte prospectiva de 171 pacientes de Vitória, ES, no período de 2004 a 2007. Cada paciente foi acompanhado por seis meses até a finalização do tratamento. Dos pacientes estudados, 59 pacientes tratados eram supervisionados por um membro familiar e 112 pelos profissionais de saúde. Foram avaliados dados sociodemográficos e clínicos dos pacientes. Diferenças entre os grupos de estudo foram avaliadas utilizando o teste qui-quadrado ou teste t de Student ao nivel de significância de 5%. RESULTADOS: A maioria dos sujeitos do estudo apresentaram bacioscopia positiva e cultura confirmada para tuberculose. Dois pacientes tinham sorologia positiva para HIV. Um número maior de pacientes no grupo supervisionado por profissionais de saúde não eram alfabetizados, comparado com aqueles pacientes do grupo supervisionado por membros familiares (p = 0,01). Todos os pacientes supervisionados por um familiar foram curados, frente a 90% dos pacientes supervisionados pelos profissionais de saúde (p=0,024). CONCLUSÕES: O sucesso do tratamento de tuberculose foi maior quando supervisionado por um familiar.OBJECTIVE: To compare tuberculosis cure rates among patients supervised by household members or health care workers. METHODS: Prospective cohort study of 171 patients treated by the program in Vitoria, Southeastern Brazil, from 2004 to 2007. Each patient was followed-up for six months until the end of the treatment. Of the patients studied, a household member supervised 59 patients and healthcare workers supervised 112 patients. Patients' sociodemographic and clinic data were analyzed. Differences between groups were assessed using chi-square test or Student's t-test. Significance level was set at 5%. RESULTS: Most patients had smear positive, culture confirmed pulmonary tuberculosis. Two patients were HIV-positive. There were more illiterate patients in the healthcare-supervised group, in comparison to those supervised by their families (p=0.01). All patients supervised by a household member were cured compared to 90% of the patients supervised by health care workers (p = 0.024). CONCLUSIONS: Successful tuberculosis treatment was more frequent when supervised by household members

Magnetotransport properties depending on the nanostructure of Fe3O4 nanowires

We have studied the magnetic behaviour of Fe3O4 nanowires (NWs) with two different diameter ranges, above 150 nm and below 60 nm, made by electrodeposition techniques into a polymeric template. The nanowires were characterized using various techniques, in particular M¨ossbauer and thermoelectrical power measurements. The stoichiometric distribution of Fe cations showed clearly the presence of the magnetite inverse spinel electronic structure. Structural analysis performed using high-resolution transmission electron microscopy revealed two kinds of nanowire morphologies depending on the size. For nanowires above 150 nm in diameter, a contiguous network of well-bound nanoparticles was obtained. Instead, with a diameter of 60 nm, a polycrystalline structure was observed. The largest nanowires presented a magnetoresistance (MR) greater than 10%, whereas the thinner nanowires had almost none