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Purpose To evaluate sphere concentration delivered to tumor and non-tumor tissue using voxel-based dosimetry as it relates to treatment, pathologic outcomes, and adverse events.Methods A retrospective, single-center analysis of patients (n = 57) with solitary HCC who were treated with Y90 radiation segmentectomy with Y90 glass microsphere infusion (TheraSphere; Boston Scientific, Marlborough, MA, USA) from 2020 to 2022 was performed. Post-treatment dosimetry was evaluated using Mirada DBx Build 1.2.0 Simplicit90Y dosimetry software. Voxel-based dosimetry and MIRD formula were utilized to calculate sphere concentration to tumor and non-tumor tissue. Time to progression (TTP), treatment response, pathologic response, and adverse events were studied.Results Fifty-seven patients with solitary tumors were analyzed with a median tumor diameter of 3.4cm (range 1.2-6.8cm). The median tumor absorbed dose was 692Gy (range, 256-1332Gy) with a median perfused treatment volume of 113mL (range, 33.6-442mL). Median sphere activity (SA) at time of delivery was 1428Bq (range, 412-2589Bq). Using voxel-based dosimetry and the MIRD formula, median tumor sphere concentration was 12,339 spheres/mL (range, 2,689 − 37,649 spheres/mL). Sphere concentration to tumor exhibited a weak, inverse correlation with perfused treatment volume (R2 = 0.25). However, tumor sphere concentration and non-tumor sphere concentration exhibited a direct, positive correlation (R2 = 0.72). Of the 52 tumors with post-treatment imaging, objective response was noted in 50 patients (96%) and complete response in 41 patients (79%). 98% of all treated tumors demonstrated a durable response at 2 years. The median time to progression for all patients was not reached with a 2-year progression rate of 11%. Multivariate analysis demonstrated target dose as the only statistically significant variable associated with TTP (p = 0.033). 14 patients underwent liver transplant. Median tumor necrosis was 99% (range, 80–100%).Conclusion Voxel-based dosimetry following Y90 radioembolization can be utilized to measure sphere concentration into tumor and non-tumoral tissue. Higher SA allows increased tumor absorbed dose with limited sphere/mL tumor capacity.

Cet article se situe dans le champ du controle organisationnel. Partant de l’inscription ancienne de la dialectique liberte-controle dans les sciences sociales et de son investigation dans les organisations post-bureaucratiques, il s’interesse aux formes de controle dans les entreprises qualifiees de liberees. Pour rendre compte de ce phenomene, il s’appuie sur l’etude de deux cas emblematiques : l’entreprise de services industriels, Chrono Flex, et le biscuitier Poult. L’article s’attache a reperer les formes de controle et, par l’analyse des situations observees, a identifier des arrangements entre formes de controle, ainsi que les roles d’acteurs mediateurs, porteurs de ces arrangements. Les resultats montrent en particulier que le controle hierarchique n’a pas ete totalement supprime, mais qu’il a plutot ete renouvele en combinaison avec d’autres formes de controle deja decrites par la litterature.

Purpose: To quantify eye lens dose in interventional radiology and assess whether neck dosimeter is a good surrogate to evaluate eye lens dosimetry. Methods: Radiation exposure was prospectively measured in 9 interventional radiologists between May and October 2017. Standard Hp(0,07) thermoluminescent dosimeters (TLDs) were worn at the neck outside the lead apron, and 2 dedicated eye lens Hp(3) TLDs were placed just above the eyes, one midline and another at the outer edge of the left eye. Correlations between eye lens and neck TLD doses were assessed with Pearson coefficient, and linear regression was used to predict eye lens dose from neck TLD values. Results: Eye lens dose without eye protection was 0.18 ± 0.11 (mean ± standard deviation; 0.08-0.41) mSv per workday and 35.3 ± 6.6 mSv (16.3-82.9) annually (200 workdays/year). Five (56%) radiologists exceeded the 20 mSv annual eye lens dose limit. Eye lens doses from left and central TLDs were 12.46 ± 3.02 and 9.29 ± 3.38 mSv, respectively ( P = .027). Mean eye lens (left and central) and neck TLD doses were 10.87 ± 2.67 and 16.56 ± 5.67 mSv, respectively ( P = .008). Pearson correlation coefficient between both eye lens TLD and between mean eye lens TLD and neck TLD doses were 0.91 and 0.92, respectively. Average of eye lens dose was 0.0179 + (0.5971 × neck dose). Conclusion: Full-time interventional radiologists are likely to suffer from deterministic radiation effects to the eye lens, especially on the left side. Neck TLD significantly overestimates eye lens dose. However, eye lens doses are highly correlated with neck doses and may be predicted from the neck TLD values.

Arteriovenous malformations (AVMs) are high-flow vascular anomalies that have demonstrated a very high recurrence rate after endovascular treatment, surgical treatment, or a combination of both. Surgical treatments have shown good response when they are small and well localized but a poor response when diffuse. A better understanding of the nature of the lesion has led to a better response rate and a safer treatment for these patients. This has been accomplished through a detailed understanding of the angioarchitecture of the lesion, enabling a tailored approach in reaching and targeting the nidus of the AVM with different liquid embolic agents, more specifically ethanol. Flow reduction techniques help in exposing the nidus to sclerosant agents. A clinical classification, the Schobinger classification, will help determine the appropriate time to start or to pursue therapy.

Objective The objective of this study was to evaluate the safety and efficacy of external beam radiation (EBR) in preventing restenosis after superficial femoral artery (SFA) stenting in comparison with a control group treated with SFA stenting only. Methods In this Institutional Review Board-approved study, patients who provided written informed consent were randomly assigned to 0 Gy or 14 Gy of EBR to the stent site 24 hours after SFA stenting. The primary end point was the angiographic binary restenosis rate 2 years after stenting. Categorical and continuous end points were respectively analyzed using logistic regression models and Wilcoxon tests. End points expressed as time to event were analyzed using a log-rank test. Results The study included 155 patients, 46 women and 109 men (mean age, 66 years; range, 45-85 years). In the 0 and 14 Gy groups, binary restenosis was present, respectively, in 44% (34/77) and 68% (52/76; P = .003) 2 years after stenting. Stent thrombosis occurred in 13% (10/78) of the 0 Gy group and in 33% (25/77) of the 14 Gy group ( P = .003). Target lesion revascularization at 2 years was 26% (25/78) in the 0 Gy group and 30% (23/77) in the 14 Gy group ( P = .56). There were no significant differences in total walking distances change from baseline to 2 years (46 ± 100 and 26 ± 79 m, respectively, in the 0 Gy and 14 Gy group; P = .25). There were no procedure-related deaths and no major amputations. Conclusions A single 14 Gy dose of EBR to the SFA stenting site did not prevent in-stent restenosis.

Anomalous placentation carries a high risk of maternal and fetal morbidity and mortality.[1][1]-[3][2] These placental abnormalities include placenta previa and the spectrum of invasive placenta, including placenta accreta, placenta increta, and placenta percreta.[2][3] However, the placentation

This work describes a 3D, paper-based assay that can isolate sub-populations of cells based on their invasiveness (i.e., distance migrated in a hydrogel) in a gradient of concentration of oxygen (O2). Layers of paper impregnated with a cell-compatible hydrogel are stacked and placed in a plastic holder to form the invasion assay. In most assays, the stack comprises a single layer of paper containing mammalian cells suspended in a hydrogel, sandwiched between multiple layers of paper containing only hydrogel. Cells in the stack consume and produce small molecules; these molecules diffuse throughout the stack to generate gradients in the stack, and between the stack and the bulk culture medium. Placing the cell-containing layer in different positions of the stack, or modifying the permeability of the holder to oxygen or proteins, alters the profile of the gradients within the stack. Physically separating the layers after culture isolates sub-populations of cells that migrated different distances, and enables their subsequent analysis or culture. Using this system, three independent cell lines derived from A549 cancer cells are shown to produce distinguishable migration behavior in a gradient of oxygen. This result is the first experimental demonstration that oxygen acts as a chemoattractant for cancer cells.

Purpose To assess response to transcatheter arterial chemoembolization (TACE) based on immune markers and tumor biology in patients with hepatocellular carcinoma (HCC) who were bridged to liver transplantation, and to produce an optimized pretransplantation model for posttransplantation recurrence risk. Materials and Methods In this institutional review board-approved HIPAA-compliant retrospective analysis, 93 consecutive patients (73 male, 20 female; mean age, 59.6 years; age range, 23-72 years) underwent TACE with doxorubicin-eluting microspheres (DEB) (hereafter, DEB-TACE) and subsequently underwent transplantation over a 5-year period from July 7, 2011, to May 16, 2016. DEB-TACE response was based on modified Response Evaluation Criteria in Solid Tumors. Imaging responses and posttransplantation recurrence were compared with demographics, liver function, basic immune markers, treatment dose, and tumor morphology. Treatment response and recurrence were analyzed with uni- and multivariate statistics, as well as internal validation and propensity score matching of factors known to affect recurrence to assess independent effects of DEB-TACE response on recurrence. Results Low-grade tumors (grade 0, 1, or 2) demonstrated a favorable long-term treatment response in 87% of patients (complete response, 49%; partial response, 38%; stable disease [SD] or local disease progression [DP], 13%) versus 33% of high-grade tumors (grade 3 or 4) (complete response, 0%; partial response, 33%; SD or DP, 67%) (P.001). Of the 93 patients who underwent treatment, 82 were followed-up after transplantation (mean duration, 757 days). Recurrence occurred in seven (9%) patients (mean time after transplantation, 635 days). Poor response to DEB-TACE (SD or DP) was present in 86% of cases and accounted for 35% of all patients with SD or DP (P.001). By using only variables routinely available prior to liver transplantation, a validated model of posttransplantation recurrence risk was produced with a concordance statistic of 0.83. The validated model shows sensitivity of 83.6%, specificity of 82.6%, and negative predictive value of 98.4%, which are pessimistic estimates. Conclusion Response to DEB-TACE is correlated with tumor biology and patients at risk for posttransplantation recurrence, and it may be associated with HCC recurrence after liver transplantation.

Objective Many investigators believe that basal adrenal venous sampling (AVS) should be done simultaneously, whereas others opt for sequential AVS for simplicity and reduced cost. This study aimed to evaluate the concordance of sequential and simultaneous AVS methods. Design and methods Between 1989 and 2015, bilateral simultaneous sets of basal AVS were obtained twice within 5 min, in 188 consecutive patients (59 women and 129 men; mean age: 53.4 years). Selectivity was defined by adrenal-to-peripheral cortisol ratio ≥2, and lateralization was defined as an adrenal aldosterone-to-cortisol ratio ≥2, the contralateral side. Sequential AVS was simulated using right sampling at −5 min (t = −5) and left sampling at 0 min (t = 0). Results There was no significant difference in mean selectivity ratio (P = 0.12 and P = 0.42 for the right and left sides respectively) and in mean lateralization ratio (P = 0.93) between t = −5 and t = 0. Kappa for selectivity between 2 simultaneous AVS was 0.71 (95% CI: 0.60–0.82), whereas it was 0.84 (95% CI: 0.76–0.92) and 0.85 (95% CI: 0.77–0.93) between sequential and simultaneous AVS at respectively −5 min and at 0 min. Kappa for lateralization between 2 simultaneous AVS was 0.84 (95% CI: 0.75–0.93), whereas it was 0.86 (95% CI: 0.78–0.94) and 0.80 (95% CI: 0.71–0.90) between sequential AVS and simultaneous AVS at respectively −5 min at 0 min. Conclusions Concordance between simultaneous and sequential AVS was not different than that between 2 repeated simultaneous AVS in the same patient. Therefore, a better diagnostic performance is not a good argument to select the AVS method.

Dans le champ de l’action sociale, s’opposent deux logiques institutionnelles, celle de l’innovation et celle de la rationalisation budgétaire. Elles semblent de prime abord inconciliables. La première, porteuse de diversité et d’idiosyncrasie, serait l’apanage des associations. La seconde donnerait la part belle aux financeurs publics en visant l’homogénéisation et la transparence de l’action associative. Le caractère irréductible de cette opposition dualiste est-il avéré ? L’article étudie les interactions entre les deux logiques à travers l’étude du cas d’une association et des modalités de son financement. Il s’attache, tout d’abord, à décrire les formes concrètes des relations association-financeurs dans le cas étudié. Puis, il analyse les processus temporels et multi-acteurs, montrant le dépassement de l’apparente incompatibilité entre les deux logiques. In the field of social action, there are two opposing institutional logics : innovation and budget rationalization. At first sight they appear irreconcilable. The first, valuing diversity and idiosyncrasy would seem to be the prerogative of non-profit organisations. The second would seem to be given pride of place by public funding, aiming at homogenisation and transparency in social action. But is the outright opposition between these two ideas insurmountable ? This article studies interaction between the two logics through the case study of a non-profit organisation and the methods of its funding. First it describes the different types of relationship between the organisation and its funders. Then it analyses the temporal and multi-player processes, showing how the apparent incompatibility between the two logics can be overcome.

International audience; La gestion des experts est un sujet important et d’actualité pour les organisations scientifiques et techniques. Alors que leur performance dépend de leur capacité à attirer, mobiliser et fidéliser des experts, elles rencontrent d’importantes difficultés en la matière. Les experts ressentent un manque de reconnaissance qui entraîne démotivation et turn over. Afin de valoriser et de fidéliser ces experts, un grand nombre d’organisations déploie un outil spécifique : la double échelle de carrière qui crée une filière promotionnelle dédiée aux experts à côté de la voie hiérarchique classique. Cet outil de GRH suscite plusieurs étonnements. Il apparaît comme une innovation RH aux organisations qui l’adoptent aujourd’hui, alors qu’il a été inventé il y a plus de 60 ans. Sa diffusion interroge également quand on considère à quel point la double échelle a été critiquée quant à son incapacité à résoudre la question de la reconnaissance des experts. Enfin, les organisations qui disposent d’une double échelle et en expérimentent les limites ne l’ont pas abandonnée pour autant. Cet article entend élucider le paradoxe de la persistance d’un outil inefficace, paradoxe incompréhensible dans une approche fonctionnaliste. S’inscrivant dans une perspective théorique très différente, les auteurs mobilisent la grille d’analyse de l’agence des outils de gestion (Chiapello & Gilbert, 2016). Sur les sept cas d’organisations de recherche et développement étudiés, les résultats montrent que la double échelle produit des effets – épistémiques, pragmatiques et politiques - qui expliquent sa prégnance, alors même qu’elle ne permet pas d’apporter une solution satisfaisante au problème de reconnaissance des experts. Cette recherche contribue à enrichir la compréhension des outils de gestion pris dans des interactions dynamiques et complexes avec leur environnement organisationnel et institutionnel. Elle donne également des pistes de réflexion aux managers et aux acteurs de la fonction RH en charge des professionnels scientifiques et techniques.

This is a case of choriocarcinoma that did not regress after chemotherapy treatment. A 30-year-old female patient (gravida 2, para 2), presented to our ER with stroke and persistent mild pelvic pain 2 months after a Caesarean section. Computed tomography (CT) revealed an ischemic left hemicerebellar region and a hypervascular mass in the pelvic region. This mass was not present on routine fetal ultrasound during pregnancy. The lesion was treated by chemotherapy after closure of a foramen ovale and insertion of an inferior vena cava (IVC) filter. After that, 2 courses of EMACO (Etoposide, Methotrexate, Actinomycin D, Cyclophosphamide, and Vincristine) chemotherapy regimen were given. Posttreatment CT showed the hypervascular mass without any changes. Arteriography showed the arteriovenous fistulae that were embolized successfully with plugs, coils, and glue. Embolization was considered due to the risk of acute hemorrhagic life-threatening complications. Eight chemotherapy courses were added after embolization. Treatment by endovascular approach and reduction of the hypervascular mass can be a valuable adjunct to chemotherapy treatment of choriocarcinoma.

Si la gestion des compétences est encore un sujet d’actualité à la fois pour les gestionnaires de ressources humaines et pour bon nombre de responsables d’entreprise, c’est que l’objet même de cette gestion ne cesse de prendre de l’importante au sein des nouveaux systèmes productifs et face aux nouvelles contraintes de l’environnement. Pourtant, ces nouvelles approches, dont on parle beaucoup, sont peu et mal connues, et ne sont que très rarement mises en perspective au plan international. Il peut donc être intéressant, partant d’un enjeu « théoriquement » similaire — la compétence — de voir de quelle façon ces logiques et ces modes de gestion ont été conceptualisés, instrumentés et implantés de chaque côté de l’Atlantique. L’analyse conduit à observer que si les deux systèmes se sont constitués de façon contingente, et que certains facteurs lourds leur sont encore associés aujourd’hui, d’autres forces poussent vers une certaine standardisation, pour ne pas dire universalisation des approches dans ce domaine désormais central de la gestion des ressources humaines., As a management style that is still in its infancy, the phenomenon of competency management has gradually grown in importance to the point that it is now a well-established practice in full development on both sides of the Atlantic. However, what is called “competency management” covers a wide range of practices in different countries, and is positioned differently, particularly as concerns France and North America. As well, this approach has not yet been well documented from a comparative standpoint.The comparison of these two national contexts shows that we are clearly faced with two distinct systems, each with its own history, its pace, and its practical details in structuring, its means of organization and of leading and also, doubtlessly, having its own structuring effects on the environments in which it is established. Competency management will thus have given rise to, under the combined effect of a number of historical, economic or structural, legislative and cultural factors, specific developments, and dependant on each of these environments. In this way, managing competencies, in its French form does not cover the same reality as does managing competencies in the American style. Several differentiating elements stand out between the two systems. The conceptual work from which skills management has developed appears more multidisciplinary in nature, more intensive, and at the same time, richer in the French context (sociology, education, ergonomics, cognitive psychology, adult education, etc.) than on the American side, where psychology is the key consideration. The centrality of performance in the debate and in the instrumentation is also clearly evident in the North American context. The key skills are first identified and measured through discriminating behaviours among the most productive workers, then these skills are defined, calibrated, and measured with a view to a certain performance level which is to be attained. What is even more significant, perhaps, is that competency management does not target the same employee categories: middle and upper management, non-unionized, on the North American side, and operators and technicians, often unionized, on the French side. As a corollary of the preferred targets, we often find reference points strongly centered on “soft” and generic skills on the American side, while more specialized knowledge and skills are given center stage on the French side. Instruments for evaluation do exist in the French context, but these seem more “rustic,” and, in a certain way, cut off from academic sources which would make it possible to render the process objective. Finally, if the American style of skills management certainly aims to upgrade internal competency capital, this aim is in parallel with a turn towards mobilization and “cultural control” in trying to promote certain values, and in ascertaining that behaviour sufficiently aligns with strategic priorities. Overall, if the system’s goals are perhaps less “strategic” and if the instrumentation in France is less noticeable, this is doubtless in favour of a more marked goal of social regulation. Competencies do not escape the legislator’s notice, and continue to be a point of collective negotiation between social partners. On the North American side, skills are found to be part of the employer initiative, and their application is strictly reserved for management.Nevertheless, analysis shows that the competency management instrumentation presents certain important similarities between North America and France. As conceptualized by both sides, one may say that, competency management is not yet truly operationalized and is far from being completely implemented in businesses, thus confirming a significant gap between popular management discourse, and the reality of practices. When it does exist, several observations are clear: (1) A “competence,” as considered as an operational variable, is mostly a shared issue. In both cases, it is an uncertainty whose optimized control has become indispensable to achieving performance; (2) the fields of competence included in a frame of reference only cover, at best, a portion of reality. A more cross-sectional and corporate approach on the one hand, a tendency more towards trade and specialization on the other, the reference points remain strategic and dependant constructs; (3) competency management only covers a small part of the personnel in place (in North American, upper management and hierarchical lines; in France, primarily operators) while competence is each time announced as an issue and as a field of organizational management; (4) only a portion of competencies is actually taken into consideration—the more generic (soft competencies) in North America, the more specialized (skills) in France—leaving aside for the most part (for the time being at least) the other constituents; (5) the linkage of competency management with other human resources sub-systems, that is to say, its purpose is only very partially guaranteed and often called into question in its final implementation; and finally, (6) this means of management, which by definition is supposed to be forward-looking and minimally projected into the future of employees and of the organization is most often guided by the logic of short-term adaptation.Based on these observations, the hypothesis of convergence for French and North American approaches can be expressed in the short or in the long term. This convergence could be promoted by several “heavy” factors: (1) internationalization of businesses, and of consulting practices, exchanges between managers, consultants and researchers, combined with a broadened publication of knowledge as to the factors for success in competency management etc.; (2) the implantation of centralized systems for similar management so as to standardize approaches by skill; (3) the unifying influence of new concepts popular with managers (“the learning organization,” “the intelligent enterprise,” “knowledge management,” etc.). On the other hand, certain characteristics of each of the two systems seem inevitably to depend on other limitations, whether these are due to legislative, statutory or conventional limitations, due to cultural pressure, through management tradition or due to a purely strategic choice. The idea of a “convergence by means of slow sedimentation” between the two systems cannot therefore be put forward at the conclusion of this article. Competency management systems are, without a doubt, decisional processes involving too many vital company elements so as to be able to easily allow a shift towards universality. But paradoxically, these systems must deal with a resource and with the criteria for using and mobilizing this resource, and these are tending to become so “universal” that their management systems may no longer remain totally centered on local or national realities., Si la gestión de competencias es aún un sujeto de actualidad para los directores de recursos humanos y para numerosos responsables de empresa, es porque el objeto mismo de esta gestión no cesa de tomar importancia en los nuevos sistemas productivos y frente a las nuevas exigencias del entorno. Sin embargo, estos nuevos enfoques, sobre los cuales se ha hablado bastante, son poco o mal conocidos y son raramente vistos desde una perspectiva internacional. Puede ser entonces interesante, partiendo de un desafío “teóricamente” semejante ‑ la competencia –, de ver de qué manera esas lógicas y esos modelos de gestión han sido conceptualizados, instrumentados e implantados de cada lado del Atlántico. El análisis de los autores conduce a observar que si los dos sistemas se han constituido de manera contingente y que ciertos factores fuertes siguen hasta ahora asociados a ellos, otros factores llevan a cierta estandardización, por no decir universalización de los enfoques en el campo – de ahora en adelante central – de la gestión de recursos humanos.

International audience; L’article porte sur un changement radical, mis en oeuvre à partir d’instrumentations locales consacrées à l’amélioration opérationnelle. Pour analyser ce changement, les auteurs ont mobilisé la théorie de l’activité. L’outil n’est rien hors de l’activité ; tel est l’axiome central de cette théorie qui trouve ses origines dans l’oeuvre scientifique de Lev Vygotski (1934/1985). Plus précisément le texte s’appuie sur l’approche proposée par Engeström (1987) qui a appliqué les idées de Vygotski à l’étude de la communication au travail et des interactions entre différents systèmes d’activité. L’application de ce cadre d’analyse montre que ce type de changement, ayant une forte composante artefactuelle et culturelle, peut être analysé en considérant l’interaction entre le système d’activité d’« amélioration opérationnelle », qui porte une intention de changement fondée sur des instruments, et le système d’activité managérial. Il apparaît que le changement au sein de l’organisation se produit à travers des apprentissages situés, liés aux tensions entre systèmes d’activité. La recherche met également en avant le rôle central de l’objet du système d’activité, comme pouvant faire le lien entre la nature à la fois locale et globale du changement organisationnel.

La gouvernance peut sembler de prime abord être uniquement une affaire entre êtres humains (partie prenantes, partenaires ou agents dans la théorie contractuelle). Il importe cependant de rechercher comment elle est techniquement équipée ; c’est-à-dire de s’intéresser aux instruments de gestion qui, au-delà de leurs fonctions explicites, ont des effets politiques et structurels. Base matérielle de l’organisation formelle, ils en constituent aussi des analyseurs. L’article mobilise comme analyseur de la gouvernance d’associations d’aide à domicile les dispositifs d’évaluation de la performance qui, importés des organisations marchandes, ont désormais cours dans les associations. Dès lors, quels rapports sociaux entre parties prenantes, constitutifs de la gouvernance, la mise en œuvre de l’évaluation révèle-t-elle ? La recherche repose sur l’étude du cas de cinq associations d’aide à domicile (52 entretiens semi-directifs et 9 observations). At first sight, governance can appear as a matter of human relationships (between stakeholders, partners or agents in contractual theory). However it is still important to direct attention towards its technical purpose. Beyond their precise functions, management tools certainly have political and structural effects. They are the material support of organisations, and the former can be studied to analyse the latter. This article analyses the governance of non-profit, home care organizations through the techniques of performance evaluation. These techniques were imported from for-profit organizations to the non-profit sector. What social relationships between stakeholders are revealed by the operation of evaluation and what does it say about governance ? The research is based on the study of the case of five home care nonprofits (52 semi-directives interviews and 9 observations).

Les réorganisations ponctuent désormais la vie des entreprises de toutes tailles et de tous secteurs. Il s’agit d’opérations souvent complexes et risquées. En cas d’échec, elles fragilisent l’entreprise et déstabilisent son personnel. Même en cas de succès, elles restent délicates. La qualité des apprentissages collectifs réalisés dans le cours même du changement conditionne le bon fonctionnement des organisations transformées. Or, la pratique n’accorde que peu d’attention à ce point ; changement et apprentissage sont habituellement pensés dans des temporalités et dans des lieux distincts et par des acteurs différents. Deux études de cas sont proposées pour illustrer à la fois les apprentissages spontanés et les tentatives d’apprentissages délibérés mises en place par les entreprises. Reorganizations are now a routine part of the life of companies of all sizes and in all sectors. These reorganizations are often complex and risky. If the reorganizations fail, they weaken the company and destabilize its workforce. And even if they succeed, they may remain precarious. The quality of organizational learnings during the change process will affect how well the organization functions after transformation. Still, little attention is paid to this point in practice. Typically, the change process and organizational learnings are disconnected in terms of time, place and people. Two case studies are offered to illustrate both spontaneous adaptation to change and the more deliberate application of organization learnings in the change process.

Diese Arbeit beschäftigt sich mit der dynamische Molekularfeldtheorie (DMFT) des Ein-Band- Hubbard-Modells im Parameterbereich des stark korrelierten Metalls. Zur Lösung des lokalen Ein- Störstellen-Anderson-Modells wird die dynamische Dichtematrixrenormierung (D-DMRG) benutzt. Nach einer Einführung in das Forschungsfeld der stark korrelierten Elektronen und der benutzten DMFT wird der Störstellenlöser D-DMRG beschrieben und ausführlich geprüft. D-DMRG ermöglicht die Berechnung von lokalen dynamischen Größen wie spektrale Dichten, Selbstenergien und dynamischen Suszeptibilitäten. Die gerade genannten dynamischen Größen werden für die semielliptische, rechteckige und dreieckige freie DOS bei halber Füllung berechnet sowie für die semielliptische DOS abseits halber Füllung. Wir benutzen den DMFT(D-DMRG) Zugang, um den Ursprung der Knicke im Realteil der Selbstenergie aufzuklären, die im Energiebereich des Quasi- Teilchens auftreten. Die Leitidee während der gesamten Arbeit ist, dass diese Knicke durch einen weiteren Zerfallskanal des Quasi-Teilchens zu Stande kommen, der durch die Ankopplung des Quasi-Teilchens an bosonische Anregungen bereit gestellt wird. Innerhalb der DMFT sind nur lokale bosonische Anregungen und zwar Spin-, Ladungs- und Cooper-Paar-Anregungen relevant. Wir haben für alle genannten DOS die benötigten lokalen dynamischen Größen berechnet und heraus bekommen, dass in allen Fällen Spin-anregungen die gesuchten bosonischen Anregungen sind, die den neuen Zerfallskanal für das Quasi-Teilchen bereit stellen., This work comprise a DMFT analysis of the metallic solutions of the single-band Hubbard model. For solving the involved single-impurity Anderson model, the dynamic density-matrix renormalization (D-DMRG) is used. After an introduction into the field of “strongly correlated electrons” and the approximation “dynamic mean-field theory”, the impurity solver D-DMRG is described and comprehensively validated. D-DMRG allows us to calculate local dynamic quantities such as spectral densities, self-energies and (dynamic) susceptibilities which we analyze for the half-filled case for the semielliptic, the rectangular and the triangular DOS and for the semielliptic DOS with doping. We use D-DMRG in a DMFT framework in order to analyze the origin of the kinks in the real part of the self-energy which occur within the energy range of the quasi-particle peak. The guiding hypothesis throughout this thesis is that those kinks are caused by an additional decay channel of the quasi-particle which is provided by the coupling of the quasi-particle to bosonic excitations. Within a DMFT framework only the local bosonic excitations such as spin-, charge- and pair-excitations are relevant. In all cases it turns out that spin-excitations are the bosonic excitations that provide the new decay channel for the quasi-particle.

Background: People with type 2 diabetes mellitus are at high risk for cardiovascular disease. In some studies, the mortality rate among people with this condition has been equivalent to that among people with cardiovascular disease. We compared cardiovascular mortality between incident cases of diabetes and cardiovascular disease. Methods: The study population was part of a random sample of 4376 men from Quebec, Canada, aged 35 to 64 years, who did not have cardiovascular disease in 1974 and who were followed until 1998. Three groups of incident cases were identified: diabetes without cardiovascular disease, first cardiovascular event (myocardial infarction, unstable angina or stroke) without diabetes, and both cardiovascular disease and diabetes. These cases were age-matched to a control group without diabetes or cardiovascular disease. Results: During the 24-year follow-up period, new diabetes without cardiovascular disease was documented in 137 men. A first cardiovascular event without diabetes was documented in 527 men. Relative to the 627 controls, men with 1 of the 2 diseases of interest had higher cardiovascular mortality (age-adjusted relative risk [RR] 3.11, 95% confidence interval [CI] 1.96–4.92) for those with diabetes and 4.46 (95% CI 3.15–6.30) for those with cardiovascular disease). However, within the first 5 years after diagnosis, men with cardiovascular disease had higher cardiovascular mortality than men with diabetes (age-adjusted RR 2.03, 95% CI 1.01–4.08). Interpretation: Men with isolated type 2 diabetes and men with isolated cardiovascular disease had similar cardiovascular mortality rates several years after initial diagnosis of either condition. These findings reinforce the need to prevent and optimally manage diabetes and cardiovascular disease.

Les mutations technologiques, économiques et sociales conduisent à faire état d’une « crise du travail ». Or, toute crise appelle des réponses gestionnaires non seulement au niveau macro, mais aussi au niveau micro des organisations productives. Dès lors se pose la question de la manière dont les équipes dirigeantes se saisissent du travail, identifient les enjeux associés et se représentent les actions nécessaires pour répondre à ces défis contemporains. Une enquête réalisée auprès de 33 dirigeants d’entreprises montre que le travail, qu’ils mettent à distance, est largement délégué au management de proximité. Les cadres dirigeants limitent leurs préoccupations à la gestion des seuls salariés sur lesquels reposent leur conception de l’avantage stratégique., Technological, economic and social changes are leading to a “labour crisis”. And yet, any crisis calls for managerial responses not only at the macro level, but also at the micro level of productive organizations. This raises the question of the way in which managerial teams seize work, identify the associated issues and imagine the actions necessary to respond to these contemporary challenges. A survey of 33 corporate senior executives shows that work, which they put at a distance, is largely delegated to local management. Senior executives limit their concerns to managing only those employees on whom their conception of strategic advantage is based., Los cambios tecnológicos, económicos y sociales están llevando a una “crisis laboral”. Pues bien, toda crisis exige respuestas de gestión no sólo a nivel macro, sino también a nivel micro de las organizaciones productivas. Esto plantea la cuestión de la forma en que los equipos de dirección son capaces de aprehender el trabajo, identificar las cuestiones asociadas e imaginar las acciones necesarias para responder a estos desafíos contemporáneos. Una encuesta realizada con 33 gerentes de empresas muestra que el trabajo que ellos abordan con distancia se delega en gran medida a la dirección local. Los altos ejecutivos limitan y concentran sus preocupaciones en la gestión de los empleados que desde su punto de vista contribuyen a la obtención de una ventaja estratégica.

Aujourd’hui largement diffusée, la gestion des compétences continue à faire face à trois questions fondamentales. D’abord, celle de la pertinence de son instrumentation : les outils de gestion des compétences restent critiqués pour leur réductionnisme, leur rapide obsolescence et leur manque de fiabilité. Ensuite, celle de son désajustement organisationnel : les pratiques de gestion des compétences semblent souvent faire abstraction des spécificités des contextes organisationnels dans lesquels elles émergent. Enfin, celle de son articulation stratégique : comment comprendre et gérer le lien entre les pratiques de gestion des compétences centrées sur l’individu et un pilotage stratégique de l’entreprise fondé sur ses compétences-clés ? En réponse à ces questions, cette contribution vise à mettre en évidence des configurations cohérentes d’instruments, de contextes organisationnels et de finalités stratégiques susceptibles de sous-tendre les dispositifs de gestion des compétences. L’analyse repose sur sept études de cas menées dans des entreprises contrastées, publiques ou privées et de tailles diverses.L’analyse comparative des cas fait émerger quatre modèles distincts de gestion des compétences : 1- un modèle de la normalisation centré sur des comportements partagés à large échelle et visant l’homogénéisation culturelle; 2- un modèle de la polyvalence permettant l’allocation flexible des ressources humaines au sein d’un périmètre d’activité; 3- un modèle du talent individuel faisant des qualités et aptitudes personnelles génériques la clé de la performance individuelle et collective; 4- et, enfin, un modèle de l’expertise centré sur la maîtrise de compétences techniques complexes et la livraison de prestations à haute valeur ajoutée. Cette modélisation permet de resituer les pratiques de gestion des compétences dans leur contexte organisationnel. Elle clarifie la valeur ajoutée qu’un système de gestion des compétences peut apporter à la réalisation d’une stratégie d’entreprise. Enfin, les choix opérationnels faits dans la construction des référentiels de compétences peuvent être compris et réfléchis à la lumière du modèle retenu., It is widely accepted that competency-based management continues to face three acute issues. The first concerns the relevance of its toolkit: competency-based management tools continue to be criticized for their reductionism, rapid obsolescence and lack of reliability. The second issue concerns its organizational maladjustment: competency-based management practices often seem to ignore the specificities of the contexts from which they emerge. Finally, the third issue pertains to its strategic articulation: how to understand and manage the link between competency-based management practices that are centred on the individual and the strategic management of the company based on its core competences? In responding to these issues, this paper aims to highlight the mechanisms, organizational contexts and strategic objectives that are likely to underpin competency-based management practices. The analysis is based on seven case studies conducted within contrasting companies: public and private, and of various sizes.Comparative analysis of these cases allows four distinct competency-based management models to emerge: 1- a standardized model centred around behaviours that are shared on a wide scale and aimed at cultural homogenization; 2- a polyvalent model that allows for the flexible allocation of human resources within an area of activity; 3- an individual talent model that makes generic personal skills and aptitudes the key to individual and collective performance; 4- and, finally, an expertise model centred around technically complex competencies and the delivery of high value-added services. This modelling enables us to situate competency-based management practices in their organizational context. It clarifies the added value that a competency-based management system can bring to the realization of a corporate strategy. Finally, the operational choices that are made in the building of competencies frameworks can be understood and considered in the light of the chosen model., Ampliamente difundido en este momento, la gestión de competencias continúa de hacer frente a tres cuestiones fundamentales. Primero, la pertinencia de su instrumentación: los útiles de gestión de competencias siguen siendo criticados por su reduccionismo, su rápida obsolescencia y su falta de fiabilidad. Segundo, su desajuste organizacional: las prácticas de gestión de competencias parecen hacer abstracción de manera frecuente de las especificidades de los contextos organizacionales dentro de los cuales éstas emergen. Por último, su articulación estratégica: ¿cómo comprender y dirigir el vínculo entre las prácticas de gestión de competencias centradas en el individuo y un pilotaje estratégico de la empresa basado sobre sus competencias claves? En respuesta a estas cuestiones, esta contribución busca poner en evidencia las configuraciones coherentes de instrumentos, de contextos organizacionales y de finalidades estratégicas susceptibles de servir de base a los dispositivos de gestión de competencias. El análisis reposa en siete estudios de caso llevados a cabo en empresas contrastadas, públicas o privadas y de talla diversa.El análisis comparativo de casos revela cuatro modelos distintos de gestión de competencias: 1- un modelo de la normalización centrado sobre los comportamientos compartidos a gran escala y destinado a la homogenización cultural; 2- un modelo de la polivalencia que permite la asignación flexible de recursos humanos dentro de un perímetro de actividad; 3- un modelo del talento individual que convierte las cualidades y aptitudes personales genéricas en la clave del rendimiento individual y colectivo; 4- y, por último, un modelo de pericia centrado en el control de competencias técnicas complejas y la prestaciones de servicios de alto valor agregado. Esta modelización permite de resituar las prácticas de gestión de competencias en su contexto organizacional. Esto clarifica el valor agregado que un sistema de gestión de competencias puede aportar a la realización de una estrategia de empresa. Para terminar, las decisiones operacionales adoptadas en la construcción de referenciales de competencias pueden ser comprendidas y esclarecidas con el modelo retenido.