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See detailShear banding modelling in cross-anisotropic rocks
Pardoen, Benoît ULg; Seyedi, D.M.; Collin, Frédéric ULg

in International Journal of Solids and Structures (in press)

Sedimentary geomaterials such as rocks frequently exhibit cross-anisotropic properties and their behaviour depends on the direction of loading with respect to their microstructure. As far as material ... [more ▼]

Sedimentary geomaterials such as rocks frequently exhibit cross-anisotropic properties and their behaviour depends on the direction of loading with respect to their microstructure. As far as material rupture is concerned, localised deformation in shear band mode appears generally before cracks and material failure. The influence of cross-anisotropy on the shear strain localisation remains an important issue and is investigated in the present study. To do so, a constitutive elastoplastic cross-anisotropic model that includes anisotropy both on the elastic and plastic characteristics is defined. For the plastic part of the model, the anisotropy of a strength parameter is introduced with a microstructure fabric tensor. Then, the fractures are modelled with finite element methods by considering the development of shear strain localisation bands and an enriched model is used to properly reproduce the shear banding. The cross-anisotropy influence on shear banding is studied through numerical applications of small and large-scale geotechnical problems that engender fractures. The two considered applications are a plane-strain biaxial compression test and an underground gallery excavation. The numerical results provide information about the influence of cross-anisotropy on the appearance and development of shear bands. It has been noticed, among other observations, that the material strength vary with the loading direction and that the development and the shape of the excavation fractured zone that develops around a gallery is strongly influenced by the material anisotropy. [less ▲]

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See detailImmune Recovery after Allogeneic Hematopoietic Stem Cell Transplantation following Flu-TBI versus TLI-ATG Conditioning
HANNON, Muriel ULg; BEGUIN, Yves ULg; Ehx, Grégory ULg et al

in Clinical Cancer Research : An Official Journal of the American Association for Cancer Research (in press)

Purpose: A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been develop to induce graft ... [more ▼]

Purpose: A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been develop to induce graft-versus-tumor effects without graft-versus-host disease (GVHD). Experimental Design: We compared immune recovery in 53 patients included in a phase II randomized study comparing nonmyeloablative HCT following either fludarabine plus 2 Gy total body irradiation (TBI arm, n=28) or 8 Gy TLI plus anti-thymocyte globulin (TLI arm, n=25). Results: In comparison to TBI patients, TLI patients had a similarly low 6-month incidence of grade II-IV acute GVHD, a lower incidence of moderate/severe chronic GVHD (P=0.02), a higher incidence of CMV reactivation (P<0.001), and a higher incidence of relapse (P=0.01). While recovery of total CD8+ T cells was similar in the two groups, with median CD8+ T cell counts reaching the normal values 40-60 days after allo-HCT, TLI patients had lower percentages of naïve CD8 T cells. Median CD4+ T cell counts did not reach the lower limit of normal values the first year after allo-HCT in the two groups. Further, CD4+ T cell counts were significantly lower in TLI than in TBI patients the first 6 months after transplantation. Interestingly, while median absolute regulatory T cell (Treg) counts were comparable in TBI and TLI patients, Treg/naïve CD4+ T cell ratios were significantly higher in TLI than in TBI patients the 2 first years after transplantation. Conclusions: Immune recovery differs substantially between these two conditioning regimens possibly explaining the different clinical outcomes observed (NCT00603954). [less ▲]

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See detailOption Replication and the Performance of a Market Timer
Hübner, Georges ULg

in Studies in Economics & Finance (in press)

The Treynor and Mazuy framework is a widely used return-based model of market timing. However, existing corrections to the regression intercept can be manipulated through derivatives trading. We propose ... [more ▼]

The Treynor and Mazuy framework is a widely used return-based model of market timing. However, existing corrections to the regression intercept can be manipulated through derivatives trading. We propose an adjustment based on Merton's option replication approach. The linear and quadratic coefficients of the regression are exploited to assess the cost of the replicating option that yields similar convexity for a passive portfolio. A similar reasoning applies for various timing patterns and in multi-factor models. The proposed framework induces a potential rebalancing risk and involves the delicate issue of choosing the cheapest option. We show that these issues can be overcome for reasonable tolerance levels. [less ▲]

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See detailLe couplage « Micro-crédit, Micro-assurance santé et Offre des soins » peut améliorer l’accessibilité aux soins de santé de qualité en milieu urbain africain : Résultats d’une expérience menée dans la zone de santé de Bandalungwa à Kinshasa, Congo.
Manzambi Kuwekita, Joseph ULg; Gosset, Christiane ULg; Guillaume, Michèle ULg et al

in Médecine et Santé Tropicales (in press)

Summary This study, based on a survey carried out in 2008, examines how coupling «microcredit, micro-insurance and health care» can improve access to quality care in the health zone of Bandalungwa, in ... [more ▼]

Summary This study, based on a survey carried out in 2008, examines how coupling «microcredit, micro-insurance and health care» can improve access to quality care in the health zone of Bandalungwa, in Kinshasa. The bivariate analysis shows a significant association between the increase in purchasing power and realization of benefit (p = 0, 001), achievement of benefit and savings (p = 0, 000) savings and insurance health and improved access to health care: according to the main results, 68.8 %t of borrowers reported an increase in their purchasing power which 81.8% making benefit. Those with savings were 24.7 times more likely to contribute to a health insurance scheme than those without; 71.9% of those who have regularly contributed to health insurance have improved their access to care. Coupling microcredit, health microinsurance and health care can improve access to quality health care at lower cost. This suggests the integration of health insurance in the primary health care system. [less ▲]

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See detailL'atlas à l'épreuve de l'image en mouvement (Warburg, Farocki, Didi-Huberman)
Hagelstein, Maud ULg; Hamers, Jérémy ULg

in MethIS : Méthodes et Interdisciplinarité en Sciences Humaines (in press)

Partant des travaux récents de Georges Didi-Huberman sur l’atlas d’images (A. Warburg) comme outil et support d’une nouvelle heuristique du montage, ce texte confronte l’installation Histoires de fantômes ... [more ▼]

Partant des travaux récents de Georges Didi-Huberman sur l’atlas d’images (A. Warburg) comme outil et support d’une nouvelle heuristique du montage, ce texte confronte l’installation Histoires de fantômes pour grandes personnes (G. Didi-Huberman, A. Gisinger, 2012), composée pour partie d’images en mouvement, à la pensée de la table warburgienne comme lieu d’une perpétuelle reconfiguration et d’une nouvelle lisibilité du monde. Se pourrait-il en effet qu’une image en mouvement, prise d’ordinaire dans un continuum clos, se dote, à travers le montage, des mêmes potentialités critiques – c’est-à-dire d’un même pouvoir inquiétant – que l’image fixe offerte au déambulateur de l’atlas ? [less ▲]

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See detailMontage et résistance du réel chez S. Kracauer: Photographie, cinéma, texte.
Hagelstein, Maud ULg; Hamers, Jérémy ULg

in Bulletin d'Analyse Phénoménologique (in press)

Partant de quelques textes dans lesquels S. Kracauer traite du rapport entre montage et réel, cet article tente de préciser et de problématiser l’ambivalence de Kracauer à l’égard de l’outil « montage » ... [more ▼]

Partant de quelques textes dans lesquels S. Kracauer traite du rapport entre montage et réel, cet article tente de préciser et de problématiser l’ambivalence de Kracauer à l’égard de l’outil « montage », notamment dans le champ cinématographique, en ouvrant la réflexion par cette double question : comment définir un « mauvais usage » du montage et, à l’opposé, comment peuvent se mettre en place les conditions d’un « bon usage » du montage selon Kracauer ? Pour y répondre, les auteurs identifient d'abord, dans l’œuvre de Kracauer, les éléments explicites et implicites (montage textuel) qui permettent de saisir au plus près ce que serait, selon le philosophe et sociologue, le principe de réalité. Ensuite, une œuvre photographique, contemporaine des quelques textes évoqués, Menschen des 20. Jahrhunderts d’August Sander, permet de mieux circonscrire les possibles concrétisations de cette pensée en la mettant à l’épreuve d’une réalisation en images et en montage. [less ▲]

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See detailThe Sequence of Cyclophosphamide and Myeloablative Total Body Irradiation in Hematopoietic Cell Transplantation for Patients with Acute Leukemia
Holter-Chakrabarty, Jennifer; Pierson, Namali; Zhang, Mei-Jie et al

in Biology of Blood & Marrow Transplantation (in press)

Limited clinical data are available to assess whether the sequencing of cyclophosphamide (Cy) and total body irradiation (TBI) changes outcomes. We evaluated the sequence in 1769 (CyTBI, n ¼ 948; TBICy, n ... [more ▼]

Limited clinical data are available to assess whether the sequencing of cyclophosphamide (Cy) and total body irradiation (TBI) changes outcomes. We evaluated the sequence in 1769 (CyTBI, n ¼ 948; TBICy, n ¼ 821) recipients of related or unrelated hematopoietic cell transplantation who received TBI (1200 to 1500 cGY) for acute leukemia from 2003 to 2010. The 2 cohorts were comparable for median age, performance score, type of leukemia, first complete remission, Philadelphia chromosomeepositive acute lymphoblastic leukemia, HLAmatched siblings, stem cell source, antithymocyte globulin use, TBI dose, and type of graft-versus-host disease (GVHD) prophylaxis. The sequence of TBI did not significantly affect transplantation-related mortality (24% versus 23% at 3 years, P ¼.67; relative risk, 1.01; P ¼.91), leukemia relapse (27% versus 29% at 3 years, P ¼ .34; relative risk, .89, P ¼.18), leukemia-free survival (49% versus 48% at 3 years, P ¼.27; relative risk, .93; P ¼ .29), chronic GVHD (45% versus 47% at 1 year, P ¼.39; relative risk, .9; P ¼ .11), or overall survival (53% versus 52% at 3 years, P ¼.62; relative risk, .96; P ¼.57) for CyTBI and TBICy, respectively. Corresponding cumulative incidences of sinusoidal obstruction syndrome were 4% and 6% at 100 days (P ¼ .08), respectively. This study demonstrates that the sequence of Cy and TBI does not impact transplantation outcomes and complications in patients with acute leukemia undergoing hematopoietic cell transplantation with myeloablative conditioning. [less ▲]

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See detail« Observation relative au poème Un Coup de Dés jamais n’abolira le Hasard par Stéphane Mallarmé » : une préface d’un nouveau genre ?
Durand, Pascal ULg

in Björn-Olav, Dozo; Saint-Amand, Denis (Eds.) Jeux et enjeux de la préface (in press)

L’« Observation relative au poème UN COUP DE DÉS JAMAIS N’ABOLIRA LE HASARD », rédigée expressément à la demande de la rédaction de la revue Cosmopolis qui en avait procuré l’édition originale sous une ... [more ▼]

L’« Observation relative au poème UN COUP DE DÉS JAMAIS N’ABOLIRA LE HASARD », rédigée expressément à la demande de la rédaction de la revue Cosmopolis qui en avait procuré l’édition originale sous une première forme, est depuis lors, assez improprement, considérée et lue comme une « préface » au Coup de dés dans sa version définitive. Émanant d’un poète ayant marqué plus d’une fois la vive défiance que lui inspirait le geste de la préface, elle doit plutôt être lue, tout d’abord, comme un texte de circonstance imposé par des contingences éditoriales et comme un commentaire visant à assurer la lisibilité d’un texte monstre en le rabattant sur des codes reçus. Examinée sous l’angle de sa construction et de son dispositif d’énonciation, cette « Observation » tient sans doute moins, en outre, d’une préface apportée après coup à un « poème » que d’un manifeste esthétique faisant « observer » et se lever, à l’horizon du texte, l’émergence d’un genre poétique sans précédent. [less ▲]

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See detailShedding Light on the b to s Anomalies
Aristizabal Sierra, Diego ULg; Vicente, Avelino ULg; Staub, Florian

in Physical Review. D, Particles, Fields, Gravitation, and Cosmology (in press)

The LHCb collaboration has recently reported on some anomalies in b→s transitions. In addition to discrepancies with the Standard Model (SM) predictions in some angular observables and branching ratios ... [more ▼]

The LHCb collaboration has recently reported on some anomalies in b→s transitions. In addition to discrepancies with the Standard Model (SM) predictions in some angular observables and branching ratios, an intriguing hint for lepton universality violation was found. Here we propose a simple model that extends the SM with a dark sector charged under an additional U(1) gauge symmetry. The spontaneous breaking of this symmetry gives rise to a massive Z′ boson, which communicates the SM particles with a valid dark matter candidate, while solving the b→s anomalies with contributions to the relevant observables. [less ▲]

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See detailLe tradipraticien est un acteur incontournable dans l’offre des soins de santé en territoire péri-urbain : équilibre entre légitimité et illégalité ?
Manzambi Kuwekita, Joseph ULg; Mbadu Kivuidi, Véronique; Bruyère, Olivier ULg et al

in Bogaert, Jan (Ed.) Territoires Périurbains (in press)

Summary This study examines people’s and public actors’s perception of traditional healers in Kisenso, and their potential integration into the health system. The findings of this study are based on focus ... [more ▼]

Summary This study examines people’s and public actors’s perception of traditional healers in Kisenso, and their potential integration into the health system. The findings of this study are based on focus groups conducted in 2013. According to the key results of this study, 100% of participants acknowledge the existence of traditional practitioners and all have used them. 80% found the care provided by these healers to be effective. However, the study participants found them to be lacking in hygiene in their handling of products. The use of traditional healers is justified in particular by the effectiveness of care, the type of illness suffered, the possibility of credit payment and their proximity. Public actors recognize both the existence of traditional healers and their effectiveness. They deplore their clandestine operation. Traditional healers claiming to be GPs (60%) and specialists (40%) say they work illegally because of the cost of administrative acts and their mistrust of intellectuals and biomedical practitioners. They complain about the insolvency of their patients who do not honor their commitments. For an effective integration of traditional healers in the health system, it would be useful to remove administrative barriers imposed on them for a balance between ancestral legitimacy and illegality in which they work, give them access to training, accept them as full participants in the health system, and explore the possibilities of contracting. [less ▲]

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See detailCREATING PERENNIAL FLOWER STRIPS: THINK FUNCTIONAL!
Uyttenbroeck, Roel ULg; Hatt, Séverin ULg; Piqueray, Julien et al

in Scientific Papers. Series A. Agronomy (in press)

In last decades, farmland biodiversity came under large threat. To counteract farmland biodiversity loss and other environmental impacts of intensive agriculture, European farmers can apply Agri ... [more ▼]

In last decades, farmland biodiversity came under large threat. To counteract farmland biodiversity loss and other environmental impacts of intensive agriculture, European farmers can apply Agri-environmental schemes. One of these is the creation of flower strips, a part of the cropping field where flowers are sown or naturally settled. Flower strips are known to increase biodiversity in the agricultural landscape, notably attracting specific insects groups, such as pollinators and natural enemies that can provide valuable pollination and biocontrol services to the crop. However, the plant species composition and management of the strips can have a large influence on the identity and amount of useful insects present in the strips, suggesting the need to develop tailored flower strips to maximize the services delivered. Functional diversity (FD) is sometimes proposed as a promising approach, focusing on plant functional traits rather than plant species itself. Yet, it is not certain that sowing a set of plant species results in the desired vegetation with the desired functional trait composition. Species from soil seed bank or dispersing from neighboring vegetation can settle in the strip, while sown species might not always be equally adapted to local conditions. To test this, we developed seed mixtures with four different levels of FD, based on flower traits, and sew them as flower strips in a conventional arable field. We monitored the vegetation to calculate the FD of the realized vegetation. While the absolute FD values of the realized vegetation were lower than the expected FD values, the realized vegetation showed the same FD gradient as expected from the sown mixtures, indicating that it is possible to manipulate FD in flower strips. [less ▲]

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See detailUsing kernels and ecological niche modelling to delineate conservation areas in an endangered patch-breeding phenotype
Denoël, Mathieu ULg; Ficetola, Francesco

in Ecological Applications (in press)

Efficient delineation of conservation areas is a great challenge in maintaining biodiversity. Kernel density estimators (KDEs) are a powerful tool in this perspective, but they have not been applied at ... [more ▼]

Efficient delineation of conservation areas is a great challenge in maintaining biodiversity. Kernel density estimators (KDEs) are a powerful tool in this perspective, but they have not been applied at the population level on patch-distributed organisms. This would be particularly worthy for species that need broad habitats beyond those where they can be sampled; such as terrestrial lands for pond-breeding amphibians. The aim of this study was to compare different approaches for the identification of suitable areas for conservation: KDE, ecological niche modelling, and a combination of KDE and niche models. Paedomorphosis was chosen as a model system because this is an important form of intraspecific variation that is present in numerous taxa, but geographically localized within species and globally endangered. 277 ponds were sampled in one of the hotspots of paedomorphosis to determine the abundance and distribution of paedomorphs (i.e. individuals retaining gills at the adult stage) of the palmate newt (Lissotriton helveticus), with emphasis on the connections between the most valuable populations. KDEs gave insights into the surface areas required to balance the maintenance of certain number of connected ponds and the respective number of disjoint areas in which the whole population is divided. The inclusion of barriers in the models helped in accurately designing the limits of the areas to protect. Alone, habitat models were not able to successfully delineate the area to protect, but the integration between terrestrial suitable areas or barriers and KDE allowed an objective identification of areas required for conservation. Overall, the best performance was observed by the KDE integrating ecological barriers, and by the combination between KDE and niche modelling. In a broader perspective, KDEs are thus a pertinent tool in providing quantitative spatial measurements to delineate conservation areas based on patch-abundance data with a specific focus to connectivity. [less ▲]

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See detailDrivers of the winter–spring phytoplankton bloom in a pristine NW Mediterranean site, the Bay of Calvi (Corsica): A long-term study (1979–2011)
Goffart, Anne ULg; Hecq, Jean-Henri ULg; Legendre, Louis

in Progress in Oceanography (in press)

This work is based on a long time series of data collected in the well-preserved Bay of Calvi (Corsica island, Ligurian Sea, NW Mediterranean) between 1979 and 2011, which include physical characteristics ... [more ▼]

This work is based on a long time series of data collected in the well-preserved Bay of Calvi (Corsica island, Ligurian Sea, NW Mediterranean) between 1979 and 2011, which include physical characteristics (31 years), chlorophyll a (chl a, 15 years), and inorganic nutrients (13 years). Because samples were collected at relatively high frequencies, which ranged from daily to biweekly during the winter-spring period, it was possible to (1) evidence the key role of two interacting physical variables, i.e. water temperature and wind intensity, on nutrient replenishment and phytoplankton dynamics during the winter-spring period, (2) determine critical values of physical factors that explained interannual variability in the replenishment of surface nutrients and the winter-spring phytoplankton bloom, and (3) identify previously unrecognized characteristics of the planktonic ecosystem. Over the >30 year observation period, the main driver of nutrient replenishment and phytoplankton (chl a) development was the number of wind events (mean daily wind speed >5 m s-1) during the cold-water period (subsurface water ≤13.5°C). According to winter intensity, there were strong differences in both the duration and intensity of nutrient fertilization and phytoplankton blooms (chl a). The trophic character of the Bay of Calvi changed according to years, and ranged from very oligotrophic (i.e. subtropical regime, characterized by low seasonal variability) to mesotrophic (i.e. temperate regime, with a well-marked increase in nutrient concentrations and chl a during the winter-spring period) during mild and moderate winters, respectively. A third regime occurred during severe winters characterized by specific wind conditions (i.e. high frequency of northeasterly winds), when Mediterranean “high nutrient - low chlorophyll” conditions occurred as a result of enhanced cross-shore exchanges and associated offshore export of the nutrient-rich water. There was no long-term trend (e.g. climatic) in either nutrient replenishment or the winter-spring phytoplankton bloom between 1979 and 2011, but both nutrients and chl a reflected interannual and decadal changes in winter intensity. [less ▲]

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See detailThe scribal repertoire of Amennakhte son of Ipuy: Describing variation across Late Egyptian registers
Polis, Stéphane ULg

in Cromwell, Jennifer; Grossman, Eitan (Eds.) Beyond Free Variation: Scribal Repertoires from Old Kingdom to Early Islamic Egypt (in press)

The aim of this chapter is to investigate diaphasic variation in the texts written by the Deir el-Medina scribe Amennakhte son of Ipuy in New Kingdom Egypt (ca. 1150 BCE) by analysing the graphemic and ... [more ▼]

The aim of this chapter is to investigate diaphasic variation in the texts written by the Deir el-Medina scribe Amennakhte son of Ipuy in New Kingdom Egypt (ca. 1150 BCE) by analysing the graphemic and linguistic features of the registers used by this individual when writing texts belonging to different genres. The registers are conceived here as selections operating within the scribal repertoire. At an empirical level, this study is intended as a first step towards a comprehensive description of the types of linguistic variation found within the written production of the Deir el-Medina community in New Kingdom Egypt (ca. 1500–1050 BCE). At a more methodological level, as a case study testing the applicability of some historical sociolinguistic methods in the field of Ancient Egyptian, which could ultimately result in refining our approach to its diachrony. [less ▲]

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See detailVocabulaire des musiques latino-américaines
Pirenne, Christophe ULg; Antouñes, G.; Leymarie, I.

Book published by Minerve (in press)

L'immense espace géographique qui va de la Terre de Feu au Sud du Texas et des côtes du Chili aux Petites Antilles fut le théâtre d'une histoire marquée par d’incessants mouvements migratoires qui ... [more ▼]

L'immense espace géographique qui va de la Terre de Feu au Sud du Texas et des côtes du Chili aux Petites Antilles fut le théâtre d'une histoire marquée par d’incessants mouvements migratoires qui débutèrent au XVIe siècle avec la colonisation. La diversité et l’ampleur de ces flux d'hommes de toutes races, de toutes provenances et de toutes croyances ont été à l'origine de phénomènes d'acculturation complexes et variés. Les musiques indigènes, européennes et africaines ont été réinterprétées, recréées pour aboutir à des formes inédites variant selon les régions ou le degré d’influence de chacune des sources. Ce vocabulaire est destiné à donner un aperçu de cette immense richesse et à éclairer le public francophone sur ces traditions musicales qui, pour certaines, se sont largement diffusées. [less ▲]

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See detailStroboscopic phenomena in superconductors with dynamic pinning landscape
Jelic, Zeljko ULg; Milosevic, Milorad; Van de Vondel, Joris et al

in Scientific Reports (in press)

Introducing artificial pinning centers is a well established strategy to trap quantum vortices and increase the maximal magnetic field and applied electric current that a superconductor can sustain ... [more ▼]

Introducing artificial pinning centers is a well established strategy to trap quantum vortices and increase the maximal magnetic field and applied electric current that a superconductor can sustain without dissipation. In case of spatially periodic pinning, a clear enhancement of the superconducting critical current arises when commensurability between the vortex configurations and the pinning landscape occurs. With recent achievements in (ultrafast) optics and nanoengineered plasmonics it has become possible to exploit the interaction of light with superconductivity, and create not only spatially periodic imprints on the superconducting condensate, but also temporally periodic ones. Here we show that in the latter case, temporal matching phenomena develop, caused by stroboscopic commensurability between the characteristic frequency of the vortex motion under applied current and the frequency of the dynamic pinning. The matching resonances persist in a broad parameter space, including magnetic field, driving current, or material purity, giving rise to unusual features such as externally variable resistance/impedance and Shapiro steps in current-voltage characteristics. All features are tunable by the frequency of the dynamic pinning landscape. These findings open further exploration avenues for using flashing, spatially engineered, and/or mobile excitations on superconductors, permitting us to achieve advanced functionalities. [less ▲]

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See detailA radio-map of the colliding winds in the very massive binary system HD93129A
Benaglia, Paula; Marcote, Benito; Moldon, Javier et al

in Astronomy and Astrophysics (in press)

Radio observations are an effective tool to discover particle acceleration regions in colliding-wind binaries, through detection of synchrotron radiation; these regions are natural laboratories for the ... [more ▼]

Radio observations are an effective tool to discover particle acceleration regions in colliding-wind binaries, through detection of synchrotron radiation; these regions are natural laboratories for the study of relativistic particles.Wind-collision region (WCR) models can reproduce the radio continuum spectra of massive binaries that contain both thermal and non-thermal radio emission; however, key constraints for models come from high-resolution imaging. Only five WCRs have been resolved to date at radio frequencies at milliarcsec (mas) angular scales. The source HD93129A, prototype of the very few known O2 I stars, is a romising target for study: recently, a second massive, early-type star about 50 mas away was discovered, and a non-thermal radio source detected in the region. Preliminary long-baseline array data suggest that a significant fraction of the radio emission from the system comes from a putative WCR. We sought evidence that HD93129A is a massive binary system with colliding stellar winds that produce non-thermal radiation, through spatially resolved images of the radio emitting regions. Methods.We completed observations with the Australian Long Baseline Array (LBA) to resolve the system at mas angular resolutions and reduced archival Australia Telescope Compact Array (ATCA) data to derive the total radio emission. We also compiled optical astrometric data of the system in a homogeneous way. We reduced historical Hubble Space Telescope data and obtained absolute and relative astrometry with milliarcsec accuracy. The astrometric analysis leads us to conclude that the two stars in HD93129A form a gravitationally bound system. The LBA data reveal an extended arc-shaped non-thermal source between the two stars, indicative of a WCR. The wind momentum-rate ratio of the two stellar winds is estimated. The ATCA data show a point source with a change in flux level between 2003-4 and 2008-9, that is modeled with a non-thermal power-law spectrum with spectral indices of - 1:03 +/- 0:09 and -1:21 +/- 0:03 respectively. The mass-loss rates derived from the deduced thermal radio emission and from the characteristics of the WCR are consistent with estimates derived by other authors. [less ▲]

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See detailStéphane Mallarmé (1842-1898)
Durand, Pascal ULg

in Sapiro, Gisèle (Ed.) Dictionnaire international Bourdieu (in press)

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See detailAbelian bordered factors and periodicity
Charlier, Emilie ULg; Harju, Tero; Puzynina, Svetlana et al

in European Journal of Combinatorics (in press)

A finite word u is said to be bordered if u has a proper prefix which is also a suffix of u, and unbordered otherwise. Ehrenfeucht and Silberger proved that an infinite word is purely periodic if and only ... [more ▼]

A finite word u is said to be bordered if u has a proper prefix which is also a suffix of u, and unbordered otherwise. Ehrenfeucht and Silberger proved that an infinite word is purely periodic if and only if it contains only finitely many unbordered factors. We are interested in abelian and weak abelian analogues of this result; namely, we investigate the following question(s): Let w be an infinite word such that all sufficiently long factors are (weakly) abelian bordered; is w (weakly) abelian periodic? In the process we answer a question of Avgustinovich et al. concerning the abelian critical factorization theorem. [less ▲]

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