La politique paradoxante de l'asile dans le canton de Berne: impacts de la gestion publique sur les agents de terrain et sur les directions d'institutions : module Travail de Master

L'auteur de cette étude s'est fixé pour objectif de mettre en évidence et d'analyser les impacts, sur les acteurs de terrain de l'asile, des réformes engagées par les pouvoirs publics bernois. L'objectif visé par cette analyse est aussi de comprendre les attentes des agents de terrain envers leurs directions, ainsi que les stratégies développées par ces dernières pour y répondre tout en assurant la pérennité de leurs institutions

Eigenmode Analysis in Plasmonics: Application to Second Harmonic Generation and Electron Energy Loss Spectroscopy

Eigenmodes are central to the study of resonant phenomena in all areas of physics. However, their use in nano-optics seems to have been hindered and delayed for various reasons. First, due to their small size, the response of nanostructures to a far-field optical excitation is mainly dipolar. Thus, preliminary studies of nanosystems through optical methods meant that only very few eigenmodes of the system were probed, and a complete eigenmode theory was not required. Second, rigorously defining eigenmodes of an open and lossy cavity is far from trivial. Finally, only few geometries allow for an analytical solution of Maxwellâs equations that can be expressed in terms of modes, rendering the use of numerical methods mandatory to study non-trivial shapes. On the other hand, modern spectroscopy techniques based on fast electron excitation, instead of optical excitation, allow going beyond the above-mentioned dipolar regime and enable the observation of high order modes. In addition, the generation of second harmonic light (SHG) by nanoparticles permits revealing higher order modes that weakly couple to planewave far-field probing. Thus, to be able to analyze the data collected with such experimental methods and comprehend them in order to make appropriate nanostructure designs, one needs to develop suitable numerical tools for the computation of eigenmodes. This is the focus of this thesis, where eigenmodes are used throughout to analyze and understand experimental and numerical results. First, different approaches used to define and compute eigenmodes are presented in details together with the surface integral equation method used in this manuscript. The second chapter presents the use of eigenmodes to study the SHG in plasmonic nanostructures. A single mode is used as an SHG source to disentangle the modal contributions from different SHG channels. For three different nanostructures, the dipolar mode gives a pure quadrupolar second harmonic (SH) response. Then, the interplay of dipolar and quadrupolar SH radiations in nanorods of different sizes is revealed through a multipolar analysis, explaining the experimental observation of the flip between forward and backward maximum SH emissions. Finally, the dynamics of the SHG from a silver nanorod generated by short pulses is investigated. By tuning the spectral position and width of the pulses, the dynamics of a single mode is observed, both in the linear and SH responses, and fits extremely well with a harmonic oscillator model. The last chapter presents the utilization of the eigenmodes to interpret electron energy loss spectroscopy (EELS) measurements. An alternative approach to compute EELS signal is presented, revealing the different paths through which the energy of the electron is dissipated. Instead of computing the work done by the electron against the scattered electric field, the Ohmic and the radiation losses are evaluated. Then, heterodimers with several shapes and compositions are studied. A rich variety of modes is found, due to the additional degree of freedom associated with the different metals. Dolmen shaped nanostructures are also investigated in great details. A rigorous analysis of the eigenmode evolution when the central horizontal nanorod is moved is performed. Finally, we study the EELS for three iterations of a Koch snowflake nanoantenna. The evolution of the modes with the iteration of the fractal is analysed and the modes are linked to the experimental EELS ma

A Holistic View on Production Systems Management

Almost every large corporation nowadays operates some sort of Production System (PS), usually built as a derivative from leading examples like the Toyota Production System. Production Systems (PSs) are introduced to increase operational performance and to eventually instill a culture of continuous improvement across the mostly globally dispersed production networks. The main question is not any longer if PSs are helpful but how to manage them. So far there is neither an answer to this question in practice nor in literature. That is, how to design and develop the content, the process and the organizational support structure of a PS, and thus providing a corporate perspective to managing PSs, is heavily under researched. The methodological approach in this paper is twofold. First, a systematic literature review was conducted to identify appropriate papers dealing with this topic. Second, we draw on interviews with corporate representatives being accountable for the PS at 11 respective companies from the Pharmaceutical industry. The companies have been selected based on their maturity of production system implementation. Interviews were transcribed and coded. We found various activities related to the three dimensions of content, process, and structure of PSs. Thereby, we provide an overview of activities for managing PSs. We add to the literature of PSs from a corporate perspective and derive several future research opportunities, such as if there are multiple ways in combining the identified activities to be successful with a PS. Our limitation is that interviewees are from the pharmaceutical industry only, yet the level of sophistication of PSs in this industry and the twofold approach mitigate the limitation

Inbreeding and selection on sex ratio in the bark beetle Xylosandrus germanus

Background Local Mate Competition (LMC) theory predicts a female should produce a more female-biased sex ratio if her sons compete with each other for mates. Because it provides quantitative predictions that can be experimentally tested, LMC is a textbook example of the predictive power of evolutionary theory. A limitation of many earlier studies in the field is that the population structure and mating system of the studied species are often estimated only indirectly. Here we use microsatellites to characterize the levels of inbreeding of the bark beetle Xylosandrus germanus, a species where the level of LMC is expected to be high. Results For three populations studied, genetic variation for our genetic markers was very low, indicative of an extremely high level of inbreeding (FIS = 0.88). There was also strong linkage disequilibrium between microsatellite loci and a very strong genetic differentiation between populations. The data suggest that matings among non-siblings are very rare (3%), although sex ratios from X. germanus in both the field and the laboratory have suggested more matings between non-sibs, and so less intense LMC. Conclusions Our results confirm that caution is needed when inferring mating systems from sex ratio data, especially when a lack of biological detail means the use of overly simple forms of the model of interest

Constraining forest certificate's market to improve cost-effectiveness of biodiversity conservation in Sao Paulo state, Brazil

The recently launched Brazilian "forest certificates" market is expected to reduce environmental compliance costs for landowners through an offset mechanism, after a long history of conservation laws based in command-and-control and strict rules. In this paper we assessed potential costs and evaluated the cost-effectiveness of the instrument when introducing to this market constraints that aim to address conservation objectives more specifically. Using the conservation planning software Marxan with Zones we simulated different scopes for the "forest certificates" market, and compared their cost-effectiveness with that of existing command-and-control (C&C), i.e. compliance to the Legal Reserve on own property, in the state of Sao Paulo. The simulations showed a clear potential of the constrained "forest certificates" market to improve conservation effectiveness and increase cost-effectiveness on allocation of Legal Reserves. Although the inclusion of an additional constraint of targeting the BIOTA Conservation Priority Areas doubled the cost (+95%) compared with a "free trade" scenario constrained only by biome, this option was still 50% less costly than the Baseline scenario of compliance with Legal Reserve at the property.The recently launched Brazilian "forest certificates" market is expected to reduce environmental compliance costs for landowners through an offset mechanism, after a long history of conservation laws based in command-and-control and strict rules. In this1110118sem informaçãosem informaçã

Coupled Mg/Ca and clumped isotope analyses of foraminifera provide consistent water temperatures

The reliable determination of past seawater temperature is fundamental to paleoclimate studies. We test the robustness of two paleotemperature proxies by combining Mg/Ca and clumped isotopes (Δ47) on the same specimens of core top planktonic foraminifera. The strength of this approach is that Mg/Ca and Δ47 are measured on the same specimens of foraminifera, thereby providing two independent estimates of temperature. This replication constitutes a rigorous test of individual methods with the advantage that the same approach can be applied to fossil specimens. Aliquots for Mg/Ca and clumped analyses are treated in the same manner following a modified cleaning procedure of foraminifera for trace element and isotopic analyses. We analysed eight species of planktonic foraminifera from coretop samples over a wide range of temperatures from 2 to 29°C. We provide a new clumped isotope temperature calibrations using subaqueous cave carbonates, which is consistent with recent studies. Tandem Mg/Ca–Δ47 results follow an exponential curve as predicted by temperature calibration equations. Observed deviations from the predicted Mg/Ca-Δ47 relationship are attributed to the effects of Fe-Mn oxide coatings, contamination, or dissolution of foraminiferal tests. This coupled approach provides a high degree of confidence in temperature estimates when Mg/Ca and Δ47 yield concordant results, and can be used to infer the past δ18O of seawater (δ18Osw) for paleoclimate studies

Zebularine reactivates silenced E-cadherin but unlike 5-Azacytidine does not induce switching from latent to lytic Epstein-Barr virus infection in Burkitt's lymphoma Akata cells

Epigenetic silencing of regulatory genes by aberrant methylation contributes to tumorigenesis. DNA methyltransferase inhibitors (DNMTI) represent promising new drugs for anti-cancer therapies. The DNMTI 5-Azacytidine is effective against myelodysplastic syndrome, but induces switching of latent to lytic Epstein-Barr virus (EBV) in vitro and results in EBV DNA demethylation with the potential of induction of lytic EBV in vivo. This is of considerable concern given that recurrent lytic EBV has been linked with an increased incidence of EBV-associated lymphomas. Based on the distinct properties of action we hypothesized that the newer DNMTI Zebularine might differ from 5-Azacytidine in its potential to induce switching from latent to lytic EBV. Here we show that both 5-Azacytidine and Zebularine are able to induce expression of E-cadherin, a cellular gene frequently silenced by hypermethylation in cancers, and thus demonstrate that both DNMTI are active in our experimental setting consisting of EBV-harboring Burkitt's lymphoma Akata cells. Quantification of mRNA expression of EBV genes revealed that 5-Azacytidine induces switching from latent to lytic EBV and, in addition, that the immediate-early lytic infection progresses to early and late lytic infection. Furthermore, 5-Azacytidine induced upregulation of the latent EBV genes LMP2A, LMP2B, and EBNA2 in a similar fashion as observed following switching of latent to lytic EBV upon cross-linking of the B-cell receptor. In striking contrast, Zebularine did not exhibit any effect neither on lytic nor on latent EBV gene expression. Thus, Zebularine might be safer than 5-Azacytidine for the treatment of cancers in EBV carriers and could also be applied against EBV-harboring tumors, since it does not induce switching from latent to lytic EBV which may result in secondary EBV-associated malignancies

Combined BRAFV600E- and SRC-inhibition induces apoptosis, evokes an immune response and reduces tumor growth in an immunocompetent orthotopic mouse model of anaplastic thyroid cancer

Anaplastic (ATC) and refractory papillary thyroid cancer (PTC) lack effective treatments. Inhibition of either oncogenic BRAF or SRC has marked anti-tumor effects in mouse models of thyroid cancer, however, neither drug induces notable apoptosis. Here we report that the SRC-inhibitor dasatinib further sensitizes BRAFV600E-positive thyroid cancer cells to the BRAFV600E-inhibitor PLX4720. Combined treatment with PLX4720 and dasatinib synergistically inhibited proliferation and reduced migration in PTC and ATC cells. Whereas PLX4720 did not induce robust apoptosis in thyroid cancer cells, combined treatment with dasatinib induced apoptosis in 4 of 6 lines. In an immunocompetent orthotopic mouse model of ATC, combined PLX4720 and dasatinib treatment significantly reduced tumor volume relative to PLX4720 treatment alone. Immune cell infiltration was increased by PLX4720 treatment and this effect was maintained in mice treated with both PLX4720 and dasatinib. Further, combined treatment significantly increased caspase 3 cleavage in vivo relative to control or either treatment alone. In conclusion, combined PLX4720 and dasatinib treatment induces apoptosis, increases immune cell infiltration and reduces tumor volume in a preclinical model of ATC, suggesting that the combination of these FDA-approved drugs may have potential for the treatment of patients with ATC or refractory PTC

Quantitative profiling of housekeeping and Epstein-Barr virus gene transcription in Burkitt lymphoma cell lines using an oligonucleotide microarray

BACKGROUND: The Epstein-Barr virus (EBV) is associated with lymphoid malignancies, including Burkitt's lymphoma (BL), and can transform human B cells in vitro. EBV-harboring cell lines are widely used to investigate lymphocyte transformation and oncogenesis. Qualitative EBV gene expression has been extensively described, but knowledge of quantitative transcription is lacking. We hypothesized that transcription levels of EBNA1, the gene essential for EBV persistence within an infected cell, are similar in BL cell lines. RESULTS: To compare quantitative gene transcription in the BL cell lines Namalwa, Raji, Akata, Jijoye, and P3HR1, we developed an oligonucleotide microarray chip, including 17 housekeeping genes, six latent EBV genes (EBNA1, EBNA2, EBNA3A, EBNA3C, LMP1, LMP2), and four lytic EBV genes (BZLF1, BXLF2, BKRF2, BZLF2), and used the cell line B95.8 as a reference for EBV gene transcription. Quantitative polymerase chain reaction assays were used to validate microarray results. We found that transcription levels of housekeeping genes differed considerably among BL cell lines. Using a selection of housekeeping genes with similar quantitative transcription in the tested cell lines to normalize EBV gene transcription data, we showed that transcription levels of EBNA1 were quite similar in very different BL cell lines, in contrast to transcription levels of other EBV genes. As demonstrated with Akata cells, the chip allowed us to accurately measure EBV gene transcription changes triggered by treatment interventions. CONCLUSION: Our results suggest uniform EBNA1 transcription levels in BL and that microarray profiling can reveal novel insights on quantitative EBV gene transcription and its impact on lymphocyte biology

Oropharyngeal Group A Streptococcal Colonization Disrupts Latent Epstein-Barr Virus Infection

Epstein-Barr virus (EBV) infects >90% of the human population within the first 2 decades of life and establishes reversible latent infection in B cells. The stimuli that lead to switching from latent to lytic EBV infection in vivo are still elusive. Group A streptococci (GAS) are a common cause of bacterial pharyngotonsillitis in children and adolescents and colonize the tonsils and pharynx of up to 20% of healthy children. Thus, concomitant presence of EBV and GAS in the same individual is frequent. Here, we show that EBV carriers who are colonized with GAS shed EBV particles in higher numbers in their saliva, compared with EBV carriers not colonized with GAS. Messenger RNA levels of the master lytic regulatory EBV gene BZLF1 were more frequently detected in tonsils from EBV carriers colonized with GAS than from EBV carriers not colonized. Heat-killed GAS, potentially mimicking GAS colonization, elicited lytic EBV in latently infected lymphoblastoid cell lines (LCLs) partially via Toll-like receptor 2 triggering, as did purified GAS peptidoglycan. Thus, colonization by GAS might benefit EBV by increasing the EBV load in saliva and thereby enhancing the likelihood of EBV spread to other host