Mueller matrix microscope with a dual continuous rotating compensator setup and digital demodulation

In this paper we describe a new Mueller matrix (MM) microscope that generalizes and makes quantitative the polarized light microscopy technique. In this instrument all the elements of the MU are simultaneously determined from the analysis in the frequency domain of the time-dependent intensity of the light beam at every pixel of the camera. The variations in intensity are created by the two compensators continuously rotating at different angular frequencies. A typical measurement is completed in a little over one minute and it can be applied to any visible wavelength. Some examples are presented to demonstrate the capabilities of the instrument.

Impacts of Globalization Processes on the Swiss National Business Elite Community : A Diachronic Analysis of Swiss Large Corporations (1980-2010)

This paper investigates the impacts of globalization processes on the Swiss business elite community during the 1980-2010 period. Switzerland has been characterized in the 20th century by its extraordinary stability and by the strong cohesion of its elite community. To study recent changes, we focus on Switzerland's 110 largest firms' by adopting a diachronic perspective based on three elite cohorts (1980, 2000, and 2010). An analysis of interlocking directorates allows us to describe the decline of the Swiss corporate network. The second analysis focuses on top managers' profiles in terms of education, nationality as well as participation in national community networks that used to reinforce the cultural cohesion of the Swiss elite community, especially the militia army. Our results highlight a slow but profound transformation of top management profiles, characterized by a decline of traditional national elements of legitimacy and the emergence of new "global" elements. The diachronic and combined analysis brings into light the strong cultural changes experienced by the national business elite community.

Correlation between charge transport and electroluminescence properties of Si-rich oxide/nitride/oxide-based light emitting capacitors.

The electrical and electroluminescence (EL) properties at room and high temperatures of oxide/ nitride/oxide (ONO)-based light emitting capacitors are studied. The ONO multidielectric layer is enriched with silicon by means of ion implantation. The exceeding silicon distribution follows a Gaussian profile with a maximum of 19%, centered close to the lower oxide/nitride interface. The electrical measurements performed at room and high temperatures allowed to unambiguously identify variable range hopping (VRH) as the dominant electrical conduction mechanism at low voltages, whereas at moderate and high voltages, a hybrid conduction formed by means of variable range hopping and space charge-limited current enhanced by Poole-Frenkel effect predominates. The EL spectra at different temperatures are also recorded, and the correlation between charge transport mechanisms and EL properties is discussed.

Elements del practicum que afavoreixen la transferència de competències

El pràcticum és un entorn privilegiat per a la transferència de competències. Des d"aquesta perspectiva, s"ha desenvolupat el projecte «Anàlisi i avaluació de la transferibilitat de competències professionals de l"Educació Social en els centres de pràctiques» (2008MQD155) a la Universitat de Barcelona durant els cursos 2008-2010. La complexitat de l"objecte d"estudi aconsellava la utilització de mètodes qualitatius. Es va optar per un disseny d"investigació-acció a partir d"espais de reflexió. Des de la percepció dels participants, s"han identificat un conjunt d"elements que afavoreixen la transferència de competències en el marc del pràcticum, entre els quals cal destacar la necessitat d"una planificació conjunta i d"una planificació específica des de cadascun dels escenaris formatius vertebrada des de la reflexió-acció de la pràctica de l"estudiant. Per fer-ho possible, és necessari que els centres de pràctiques i els centres universitaris es reconeguin corresponsables de la formació pràctica.

Fusion weld metal solidification:Continuum from weld interface to centerline

We present a brief résumé of the history of solidification research and key factors affecting the solidification of fusion welds. There is a general agreement of the basic solidification theory, albeit differing - even confusing - nomenclatures do exist, and Cases 2 and 3 (the Chalmers' basic boundary conditions for solidification, categorized by Savage as Cases) are variably emphasized. Model Frame, a tool helping to model the continuum of fusion weld solidification from start to end, is proposed. It incorporates the general solidification models, of which the pertinent ones are selected for the actual modeling. The basic models are the main solidification Cases 1…4. These discrete Cases are joined with Sub-Cases: models of Pfann, Flemings and others, bringing needed Sub-Case variables into the model. Model Frame depicts a grain growing from the weld interface to its centerline. Besides modeling, the Model Frame supports education and academic debate. The new mathematical modeling techniques will extend its use into multi-dimensional modeling, introducing new variables and increasing the modeling accuracy. We propose a model: melting/solidification-model (M/S-model) - predicting the solute profile at the start of the solidification of a fusion weld. This Case 3-based Sub-Case takes into account the melting stage, the solute back-diffusion in the solid, and the growth rate acceleration typical to fusion welds. We propose - based on works of Rutter & Chalmers, David & Vitek and our experimental results on copper - that NEGS-EGS-transition is not associated only with cellular-dendritic-transition. Solidification is studied experimentally on pure and doped copper with welding speed range from 0 to 200 cm/min, with one test at 3000 cm/min. Found were only planar and cellular structures, no dendrites - columnar or equiaxed. Cell sub structures: rows of cubic elements we call "cubelettes", "cell-bands" and "micro-cells", as well as an anomalous crack morphology "crack-eye", were detected, as well as microscopic hot crack nucleus we call "grain-lag cracks", caused by a grain slightly lagging behind its neighbors in arrival to the weld centerline. Varestraint test and R-test revealed a change of crack morphologies from centerline cracks to grainand cell boundary cracks with an increasing welding speed. High speed made the cracks invisible to bare eye and hardly detectable with light microscope, while electron microscope often revealed networks of fine micro-cracks.

Sensing the light environment in plants: photoreceptors and early signaling steps.

Plants must constantly adapt to a changing light environment in order to optimize energy conversion through the process of photosynthesis and to limit photodamage. In addition, plants use light cues for timing of key developmental transitions such as initiation of reproduction (transition to flowering). Plants are equipped with a battery of photoreceptors enabling them to sense a very broad light spectrum spanning from UV-B to far-red wavelength (280-750nm). In this review we briefly describe the different families of plant photosensory receptors and the mechanisms by which they transduce environmental information to influence numerous aspects of plant growth and development throughout their life cycle.

Les neurosciences au Tribunal : de la responsabilité à la dangerosité, enjeux éthiques soulevés par la nouvelle loi française

AIM: In the past few years, spectacular progress in neuroscience has led to the emergence of a new interdisciplinary field, the so-called "neurolaw" whose goal is to explore the effects of neuroscientific discoveries on legal proceedings and legal rules and standards. In the United States, a number of neuroscientific researches are designed specifically to explore legally relevant topics and a case-law has already been developed. In Europe, neuroscientific evidence is increasingly being used in criminal courtrooms, as part of psychiatric testimony, nourishing the debate about the legal implications of brain research in psychiatric-legal settings. Though largely debated, up to now the use of neuroscience in legal contexts had not specifically been regulated by any legislation. In 2011, with the new bioethics law, France has become the first country to admit by law the use of brain imaging in judicial expertise. According to the new law, brain imaging techniques can be used only for medical purposes, or scientific research, or in the context of judicial expertise. This study aims to give an overview of the current state of the neurolaw in the US and Europe, and to investigate the ethical issues raised by this new law and its potential impact on the rights and civil liberties of the offenders. METHOD: An overview of the emergence and development of "neurolaw" in the United States and Europe is given. Then, the new French law is examined in the light of the relevant debates in the French parliament. Consequently, we outline the current tendencies in Neurolaw literature to focus on assessments of responsibility, rather than dangerousness. This tendency is analysed notably in relation to the legal context relevant to criminal policies in France, where recent changes in the legislation and practice of forensic psychiatry show that dangerousness assessments have become paramount in the process of judicial decision. Finally, the potential interpretations of neuroscientific data introduced into psychiatric testimonies by judges are explored. RESULTS: The examination of parliamentary debates showed that the new French law allowing neuroimaging techniques in judicial expertise was introduced in the aim to provide a legal framework that would protect the subject against potential misuses of neuroscience. The underlying fear above all, was that this technology be used as a lie detector, or as a means to predict the subject's behaviour. However, the possibility of such misuse remains open. Contrary to the legislator's wish, the defendant is not fully guaranteed against uses of neuroimaging techniques in criminal courts that would go against their interests and rights. In fact, the examination of the recently adopted legislation in France shows that assessments of dangerousness and of risk of recidivism have become central elements of the criminal policy, which makes it possible, if not likely that neuroimaging techniques be used for the evaluation of the dangerousness of the defendant. This could entail risks for the latter, as judges could perceive neuroscientific data as hard evidence, more scientific and reliable than the soft data of traditional psychiatry. If such neuroscientific data are interpreted as signs of potential dangerousness of a subject rather than as signs of criminal responsibility, defendants may become subjected to longer penalties or measures aiming to ensure public safety in the detriment of their freedom. CONCLUSION: In the current context of accentuated societal need for security, the judge and the expert-psychiatrist are increasingly asked to evaluate the dangerousness of a subject, regardless of their responsibility. Influenced by this policy model, the judge might tend to use neuroscientific data introduced by an expert as signs of dangerousness. Such uses, especially when they subjugate an individual's interest to those of society, might entail serious threats to an individual's freedom and civil liberties.

Can the administration be trusted? An analysis of the concept of trust, applied to the public sector

In the first part of this paper, we present the various academic debates and, where applicable, questions that remain open in the literature, particularly regarding the nature of trust, the distinction between trust and trustworthiness, its role in specific relationships and its relationship to control. We then propose a way of demarcating and operationalizing the concepts of trust and trustworthiness. In the second part, on the basis of the conceptual clarifications we present, we put forward a number of "anchor points" regarding how trust is apprehended in the public sector with regard to the various relations hips that can be studied. Schematically, we distinguish between two types of relations hips in the conceptual approach to trust: on one hand, the trust that citizens, or third parties, place in the State or in various public sector authorities or entities, and on the other hand, trust within the State or the public sector, between its various authorities, entities, and actors. While studies have traditionally focused on citizens' trust in their institutions, the findings, limitations and problems observed in public - sector coordination following the reforms associated with New Public Management have also elicited growing interest in the study of trust in the relationships between the various actors within the public sector. Both the theoretical debates we present and our propositions have been extracted and adapted from an empirical comparative study of coordination between various Swiss public - service organizations and their politico - administrative authority. Using the analysis model developed for this specific relationship, between various actors within the public service, and in the light of theoretical elements on which development of this model was based, we propose some avenues for further study - questions that remain open - regarding the consideration and understanding of citizens' trust in the public sector.

Non-invasive prenatal testing for aneuploidy and beyond: challenges of responsible innovation in prenatal screening.

This paper contains a joint ESHG/ASHG position document with recommendations regarding responsible innovation in prenatal screening with non-invasive prenatal testing (NIPT). By virtue of its greater accuracy and safety with respect to prenatal screening for common autosomal aneuploidies, NIPT has the potential of helping the practice better achieve its aim of facilitating autonomous reproductive choices, provided that balanced pretest information and non-directive counseling are available as part of the screening offer. Depending on the health-care setting, different scenarios for NIPT-based screening for common autosomal aneuploidies are possible. The trade-offs involved in these scenarios should be assessed in light of the aim of screening, the balance of benefits and burdens for pregnant women and their partners and considerations of cost-effectiveness and justice. With improving screening technologies and decreasing costs of sequencing and analysis, it will become possible in the near future to significantly expand the scope of prenatal screening beyond common autosomal aneuploidies. Commercial providers have already begun expanding their tests to include sex-chromosomal abnormalities and microdeletions. However, multiple false positives may undermine the main achievement of NIPT in the context of prenatal screening: the significant reduction of the invasive testing rate. This document argues for a cautious expansion of the scope of prenatal screening to serious congenital and childhood disorders, only following sound validation studies and a comprehensive evaluation of all relevant aspects. A further core message of this document is that in countries where prenatal screening is offered as a public health programme, governments and public health authorities should adopt an active role to ensure the responsible innovation of prenatal screening on the basis of ethical principles. Crucial elements are the quality of the screening process as a whole (including non-laboratory aspects such as information and counseling), education of professionals, systematic evaluation of all aspects of prenatal screening, development of better evaluation tools in the light of the aim of the practice, accountability to all stakeholders including children born from screened pregnancies and persons living with the conditions targeted in prenatal screening and promotion of equity of access.

Optical trapping: a review of essential concepts

Optical tweezers are an innovative technique for the non-contact, all-optical manipulation of small material samples, which has extraordinarily expanded and evolved since its inception in the mid-80s of the last century. Nowadays, the potential of optical tweezers has been clearly proven and a wide range of applications both from the physical and biological sciences have solidly emerged, turning the early ideas and techniques into a powerful paradigm for experimentation in the micro- and nanoworld. This review aims at highlighting the fundamental concepts that are essential for a thorough understanding of optical trapping, making emphasis on both its manipulation and measurement capabilities, as well as on the vast array of important biological applications appeared in the last years.

The role of MAR elements in DNA recombination

The untargeted integration of foreign DNA into the mammalian cell genome, extensively used in gene therapy and biotechnology, remains an incompletely understood process. It is believed to be based on cellular DNA double strand break (DSB) repair machinery and to involve two major steps: i) the formation of long gene arrays (concatemers), and ii) recombination of the resulting concatemer with the genome. The main DSB repair pathways in eukaryotes include non-homologous end-joining (NHEJ), homologous recombination (HR), and microhomology-mediated end-joining (MMEJ). However, it is still not clear, which of these pathways are responsible for transgene integration. Here, we show that NHEJ is not the primary pathway used by mammalian cells in the transgene integration process, while the components of the HR pathway seem to be important for genomic integration but not concatemerization. Instead, concatemer formation appears to be mediated by a subset of the MMEJ pathway, termed synthesis-dependent MMEJ (SD-MMEJ). This mechanism also seems to be preferentially used for plasmid integration into the genome, as confirmed by the analysis of plasmid-to-genome junction sequences, which were found to display an SD-MMEJ pattern. Therefore, we propose the existence of two distinct SD-MMEJ subpathways, relying on different subsets of enzymes. One of these mechanisms appears to be responsible for concatemerization, while the other mechanism, partially dependent in HR enzymes, seems to mediate recombination with the genome. Previous studies performed by our group suggested that matrix attachment regions (MARs), which are epigenetic regulatory DNA elements that participate in the formation of chromatin boundaries and augment transcription, may mediate increased plasmid integration into the genome of CHO cells by stimulating DNA recombination. In the present work, we demonstrate that MAR-mediated plasmid integration results from the enhanced SD-MMEJ pathway. Analysis of transgene integration loci and junction DNA sequences validated the prevalent use of this pathway by the MAR elements to target plasmid DNA into gene-rich areas of the CHO genome. We propose that this finding should in the future help to engineer cells for improved recombinant protein production. In addition to investigating the process of transgene integration, we designed recombination assays to better characterize the components of the MMEJ and SD-MMEJ pathways. We also used CHO cells expressing cycle-sensitive reporter genes to demonstrate a potential role of HR proteins in the cell cycle regulation.

Presentació: Justícia Juvenil : elements per un debat

Ens han demanat que en aquesta edició de Temps d'Educació es presenti una qüestió difícil, i pel que sembla incomoda, que sobrepassa els idealismes pedagògics destinats als «sants innocents» i ens situa més enllà de certes omnipotències tècniques que semblen voler reduir qualsevol problema infantil o juvenil a l'àmbit d'una educació curricular. Es tracta de la Justícia de Menors. Per aixo agraïm l'aportació de totes les persones que des del coneixement i l'experiència en han ofert generosament els seus escrits i la seva veu com a elements introductoris per a un debat obert.