185 resultados para Environmental innovation


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Aujourd'hui plus que jamais, le développement économique ne peut se faire au détriment de notre environnement naturel. Dès lors se pose la question de savoir comment parvenir à maintenir la compétitivité d'une économie, tout en tenant compte de l'impact qu'elle a sur révolution du cadre naturel. La présente recherche propose d'investiguer sur la question en se penchant sur les politiques publiques de promotion économique, et plus spécifiquement sur la politique régionale. Faut-il maintenir la confiance dans les courants néoclassiques, comme le laisse supposer la situation actuelle, renforcer la position d'une économie s'inscrivant au sein d'un cadre socio-environnemental ou encore repenser notre mode de fonctionnement économique quant à son développement ? Dans le cas présent, la politique régionale suisse est évaluée à la lumière de trois stratégies de développement économique. D'une part, il y a l'économie fondée sur la connaissance. Cette dernière est à la base de la philosophie actuelle en matière de politique régionale. Ensuite, il y a l'écologie industrielle, qui pour sa part fait la promesse d'un développement économique éco-compatible. Enfin, la troisième stratégie est celle de l'économie de fonctionnalité, qui propose de maximiser l'efficience d'une unité de matière première en limitant notamment la notion de propriété. Au travers d'une grille d'analyse construite sur le modèle des géographies de la grandeur, les trois stratégies sont confrontées aux objectifs de la nouvelle politique régionale suisse (NPR) ainsi qu'à ses modalités de mise en oeuvre. Il en ressort qu'en l'état actuel, la stratégie misant sur l'économie de la connaissance est la plus à même de relever le défi d'un développement économique durable. Toutefois, moyennant adaptations, les autres stratégies pourraient également se révéler être pertinentes. On constate notamment que les éléments clés sont ici l'innovation, ainsi que les dimensions spatiale et temporelle des stratégies. Nous recommandons dès lors d'adopter une approche territorialisée du développement économique, selon une logique de projet au sens de Boltanski & Chiapello. A notre sens, seules les propositions à même de fédérer les acteurs et disposant d'une vision intégrée du développement ont une chance de permettre un développement économique en harmonie avec notre cadre environnemental. - Today more than ever, economic development can't go ahead without consideration for our natural environment. This lays us with the question of how to maintain the competitiveness of an economy, and at the same time to manage the impact of it on the natural frame. This research aims to investigate this question through public policies fostering economy, more specifically through the regional policy. Must one trust the neo-classical way, as the actual situation let's think about it, reinforce the position of an economy within a socio- environmental frame or moreover reinvent our economical modus regarding development? In this case, an assessment of the Swiss regional policy is lead through three strategies of economic development. First, there is the knowledge economy. It is the core concept of the actual philosophy regarding regional policy. Second, there is the industrial ecology which aims to promote an eco-compatible economic development. Last, there is the functional economy, which proposes to maximize the efficiency of every used unit of natural resources by limiting in particular the notion of propriety. Through an analytic frame built on the model of geographies of greatness (géographies de la grandeuή, the three strategies are confronted to the objectives of the Swiss new regional policy (NRP) as well as its implementation. It turns out that actually, the strategy laying on the knowledge economy happens to be the best solution in order to promote a sustainable economic development. Nevertheless, with few adaptations, the other strategies could be pregnant as well. What we can see is that key- elements are here the innovation, as well as the spatial and temporal dimensions of these strategies. We recommend therefore to adopt a territorialised approach of economic development, with a project-based logic as meant by Boltanski & Chiapello. We are convinced that only propositions which are able to unit actors, and with an integrated point of view, have a chance to promote economic development in harmony with our environmental frame.

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Neuronal subpopulations of dorsal root ganglion (DRG) cells in the chicken exhibit carbonic anhydrase (CA) activity. To determine whether CA activity is expressed by DRG cells maintained in in vitro cultures, dissociated DRG cells from 10-day-old chick embryos were cultured on a collagen substrate. The influence exerted by environmental factors on the enzyme expression was tested under various conditions of culture. Neuron-enriched cell cultures and mixed DRG-cell cultures (including numerous non-neuronal cells) were performed either in a defined medium or in a horse serum-supplemented medium. In all the tested conditions, subpopulations of cultured sensory neurons expressed CA activity in their cell bodies, while their neurites were rarely stained; in each case, the percentage of CA-positive neurons declined with the age of the cultures. The number and the persistence of neurons possessing CA activity as well as the intensity of the reaction were enhanced by addition of horse serum. In contrast, the expression of the neuronal CA activity was not affected by the presence of non-neuronal cells or by the rise of CO2 concentration. Thus, the appearance and disappearance of neuronal subpopulations expressing CA activity may be decisively influenced by factors contained in the horse serum. The loss of CA-positive neurons with time could result from a cell selection or from genetic repression. Analysis of the time curves does not support a preferential cell death of CA-positive neurons but suggests that the eventual conversion of CA-positive neurons into CA-negative neurons results from a loss of the enzyme activity. These results indicate that the phenotypic expression of cultured sensory neurons is dependent on defined environmental factors.

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Primary sensory neurons were grown under four conditions of culture. The influence of nonneuronal cells, horse serum or both was studied on the phenotypic expression of certain neuronal subpopulations. The number of neurons expressing acetylcholinesterase, alpha-bungarotoxin-binding sites or a high uptake capacity for glutamine was enhanced by nonneuronal cells. The horse serum increases the neuronal subpopulation exhibiting a carbonic anhydrase activity. Certain phenotypic changes fit conditions consistent with an epigenetic induction rather than a cell selection.

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Environmental enrichment paradigms in adult laboratory animals, consisting of physical, perceptual, and social stimulation, have been shown to affect synapse and cell morphology in sensory cortex and enhance learning ability, whereas enrichment, which is in harmony with the animal's natural habitat may have even greater implications for plasticity. Previous studies in our laboratory have shown that whisker stimulation induced the formation of synapses and spines in the corresponding barrel. In the present study adult C57/Bl6J female laboratory mice at 6 weeks of age were placed during 2 months in a protected enrichment enclosure in a forest clearing at the Chisti Les Biological Station, Tvier, Russia. We analyzed neuropil ultrastructure in the C2 barrel using serial-section electron microscopy on a total of eight mice (n=4 enriched, n=4 standard cagemate controls). Quantitative analyses of volumes of neuropil showed a significant increase in excitatory and inhibitory synapses on spines and excitatory synapses on dendritic shafts in the C2 barrel in the enriched group compared with standard cagemate controls. These results demonstrate that naturalistic experience alters the synaptic circuitry in layer IV of the somatosensory cortex, the first cortical relay of sensory information, leaving a lasting trace that may guide subsequent behavior.

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"Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity" states the WHO. However, the current focus in this important area seems to be on reducing diseases, while less attention is paid on aspects how to increase the well-being of populations. This paper reviews three examples where well-being has drawn attention of the public and policy makers, and compares the policies of two wealthy countries. The first example is noise. Noise can reduce sleep quality and cause physiological, mental, and social effects. In Switzerland, noise receives a lot of attention by the public. Swiss laws are extensive, e.g., they prohibit trucks and planes from traveling at night. In the USA, there is little public attention and no national strategy against environmental noise. The second example is aesthetics and recreation. Many humans seek contact with the beauty of nature. The USA and Switzerland have similar strategies for achieving clear waters, while the protection of scenic views is approached very differently. Lifestyle is the last example. In the USA, the desire for individual freedom is a leading cause for suburban sprawl, a car-dependent sedentary lifestyle resulting in obesity, asthma and loss of community spirit. In Switzerland, a strict land use planning seeks to balance individual and public interests and stresses public transportation, which seems to be a more promising approach. Paying attention to aspects of well-being while developing political strategies might be a promising model to tackle environmental problems. Successful strategies employed so far seem to include the public, local authorities, politicians and scientists in this process, which might have been a key for their success. [Authors]

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Research suggests that respiratory patterns may reflect general dimensions of emotional response. In this study, we investigated the relationships between judgments of affective valence (pleasantness) and arousal and respiratory responses to acoustic stimuli. Sixteen environmental noises and 16 musical fragments of 30 s duration were presented to 31 participants, while respiration, skin conductance level and heart rate were recorded. Judgments of valence and arousal were registered using the 9-point Self-Assessment Manikin. For noises, breathing accelerated and minute ventilation augmented with decreases in pleasantness for low-arousal stimuli and with increases in arousal for positive stimuli. For music, breathing accelerated and minute ventilation augmented with increases both in rated valence and arousal. Skin conductance level increased with arousal ratings for music but not for noises, whereas mean heart rate increased with rated arousal for noises but not for music. Although both noises and music are sound-vibrations, differences in the relationships between affective judgments and physiological responses were found suggesting differences in the processing of the two types of acoustic stimuli. [Authors]

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Diagnosis of immunoallergenic pathologies due to microorganisms such as hypersensitivity pneumonitis includes detection of circulating specific antibodies. Detection of precipitins has classically been performed using immunoprecipitation techniques with crude antigenic extracts from microorganisms implicated as etiologic agents. However, these techniques lack standardization because of the different composition of fungal antigenic extracts from one batch to another. Therefore, there is high interest in developing standardized serological diagnostic methods using recombinant antigens. Immunoproteomics have proved to be useful for identifying the immunogenic proteins in several microorganisms linked to hypersensitivity pneumonitis. With this approach, the causative microorganisms are first isolated from the environment of patients. Then the proteins are separated by two-dimensional electrophoresis and revealed by Western blotting with sera of different patients suffering from the disease compared to sera of asymptomatic exposed controls. Immunoreactive proteins are identified by mass spectrometry. Identified immunoreactive proteins found to be specific markers for the disease could be subsequently produced as recombinant antigens using various expression systems to develop ELISA tests. Using recombinant antigens, standardized ELISA techniques can be developed, with sensitivity and specificity reaching 80% and 90%, respectively, and more if using a combination of several antigens. Immunoproteomics can be applied to any environmental microorganisms, with the aim of proposing panels of recombinant antigens able to improve the sensitivity and standardization of serologic diagnosis of hypersensitivity pneumonitis, but also other mold-induced allergic diseases such as allergic broncho pulmonary aspergillosis or asthma.

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This paper investigates the use of ensemble of predictors in order to improve the performance of spatial prediction methods. Support vector regression (SVR), a popular method from the field of statistical machine learning, is used. Several instances of SVR are combined using different data sampling schemes (bagging and boosting). Bagging shows good performance, and proves to be more computationally efficient than training a single SVR model while reducing error. Boosting, however, does not improve results on this specific problem.

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Abstract The late Neoproterozoic or Ediacaran period, (635 to -543 Ma) is a primordial time in the Earth history corresponding to the beginning of animal life and the most extreme ice ages on Earth. In this dissertation, palaeoenvironmental conditions were reconstructed for Ediacaran, post-Gaskiers shelf deposits in SW- Gondwana and their changes were evaluated according to the diversity of organisms. The present study addresses the question of interactions between biodiversity and environmental change by using the elemental and isotopic geochemistry of sedimentary rocks and associated organic matter, as well as the distribution of hydrocarbon biomarkers. The studied sedimentary sequences are from a large basin extended from the Paraguay belt to the Rio de la Plata craton, including the Corumbâ Group in SW-Brazil (Paraguay belt), the Arroyo del Soldado Group in Uruguay and the Sierras Bayas Group in Argentina (both in the Rio de la Plata craton). Several geochemical signatures of the sediments from Corumbâ and Sierras Bayas groups provides evidence for an euxinic setting in the Ediacaran Ocean: 1) The occurrence of syngenetic pyrite in the Corumbâ Group together with hydrocarbon biomarkers of an anoxic microbial consortium including traces of gammacerane, a distribution of hopanes with maxima at C29 as well as a low pristane/phytane (Pr/Ph) ratio; 2) the occurrence of 34S enrichments within sulfides of the Sierras Bayas Group exceeding the sulfur isotopic composition of coeval carbonate-associated sulfate. In the Arroyo del Soldado Group, an event of reducing conditions was revealed by higher concentrations of redox-sensitive trace elements and negative 513Ccar shifts in all sections. This event is extended to the whole unit in the deepest section and is restricted to tempestites in the two other shallow sections. The persistent negative. ôl3Ccar values recorded at the basinal setting implies strong isotopic gradient between shallow and deep water environments and therefore, a locus of deposition below the redox chemocline. In all studied sections, the excursions, the strong enrichment of authigenic trace-elements, the occurrence of longer chain «-alkanes, gammacerane and low Pr/Ph and Ph/>;-C]a ratios, combined with the previous sedimentological and paleontological observations indicate that the chemistry of the ocean was strongly controlled by the oxygen availability; waters being moderately oxic at the surface and anoxic at depth for much of the Neoproterozoic. This water column stratification was favourable to the storage of large amounts of nutrients in the deep ocean. During upwelling periods, the export of these nutrient-rich waters may have triggered an important bioproductivity in surface waters. Drops in Al3Cc,,.](Cr and positive ôl3Ccllr excursions highlight the increase in primary productivity. Preservation of organic carbon was ensured by reducing conditions at the bottom. The Al3ccar.kcr excursions could also reflect changes in the composition of the primary biomass. New geochemical evidence from SW-Gondwana sections supports a stratified Ediacaran ocean, outside restricted or hypersaline environments, in the aftermath of glaciations. The association of ocean stratification and the appearance of metazoans support the model that the evolution of eukaryotic life was related to the increase of oxygen levels in surface environments due to an efficient recycling of nutrients in the anoxic deep ocean. Résumé Le Néoprotérozoïque terminal, ou Édiacarien (635 à -543 Ma), est un période de première importance dans l'histoire de la Terre, car elle correspond a l'apparition des métazoaires pendant un intervalle de glaciations extrêmes. Le présent mémoire se propose de reconstituer les conditions paléoenvironnementales des dépôts de plateforme mis en place durant l'Édiacarien, au sud-ouest du Gondwana. Les interactions entre changements environnementaux et biodiversité sont évaluées en s'appuyant d'une part sur la composition élémentaire et isotopique des roches sédimentaires et de leur matière organique, et d'autre part sur la distribution moléculaire de biomarqueurs hydrocarbonés. Les séquences sédimentaires étudiées proviennent d'un grand bassin qui s'étend de la chaîne du Paraguay jusqu'au craton du Rio de la Plata. La séquence du Groupe Corumbâ au Sud Ouest du Brésil se situe dans la chaîne du Paraguay, tandis que le Groupe Arroyo del Soldado en Uruguay et le Groupe Sierras Bayas en Argentine sont situés sur le craton du Rio de la Plata. L'étude géochimique des sédiments des groupes Corumbâ et Sierras Bayas révèle de façon claire des conditions euxiniques dans l'océan édiacarien. On trouve ainsi, dans le Groupe Corumbâ, les biomarqueurs d'un cortège microbien anoxique et sulfurique comprenant des bactéries sulfato-réductrices, et dans les sulfures du Groupe Sierras Bayas, des enrichissements en Î4S excédant les rapports isotopiques du soufre dans le sulfate cogénétique associé aux carbonates. Dans la séquence de l'Arroyo del Soldado, un événement réducteur est mis en évidence par des teneurs plus élevées en éléments traces sensibles aux conditions redox et par des excursions négatives du 613Ccardans toutes les coupes. Cet événement affecte la totalité de la section la plus profonde et n'apparaît que dans les tempestites dans les sections les moins profondes. La persistance de valeurs négatives du ô13Ccarau large implique un gradient isotopique prononcé entre les environnements superficiels et profonds, et donc, ta présence d'une chémocline redox. Les excursions du. ôBCcar, l'enrichissement authigène en éléments traces, la présence de gammacérane et de rt-alcanes à longue chaîne, ainsi que de faibles rapports Pr/Ph et Ph/«-Cl8, viennent s'ajouter aux observations préliminaires sur la sédimentologie et la paléontologie pour indiquer que la chimie de l'océan était fortement contrôlée par la disponibilité d'oxygène, les eaux étant modérément oxiques à la surface et anoxiques en profondeur pendant la plus grande partie du Néoprotérozoïque. La stratification de la colonne d'eau était favorable au stockage de grandes quantités de nutriments dans l'océan profond. Dans les zones d'upwelling, la migration d'eaux profondes riches en nutriment vers la surface a pu provoquer une bioproductivité prononcée dans les eaux de surface. La conservation du carbone organique était assurée par les conditions anoxiques prévalant au fond. Les excursions du A13Ccar.kt.r pourraient aussi refléter des changements dans la biomasse primaire. Le présent travail apporte donc de nouvelles preuves qu'un océan stratifié s'est maintenu à la suite des glaciations néoprotérozoïques dans le Sud Ouest du Gondwana. L'association d'un océan stratifié et de l'apparition de la vie animale est en accord avec le modèle stipulant que l'évolution de la vie est associée à une meilleure oxygénation des environnements de surface. Résumé pour le grand public La période Ediacarienne (635 à -543 Ma) à la fin du Précambrien est l'une de plus énigmatiques dans l'histoire de la Terre, car elle est caractérisée par la diversification de la vie multicellulaire (eucaryote) pendant un intervalle de glaciations extrêmes. Dans ce travail de thèse, nous cherchons à déceler l'existence éventuelle d'un lien entre ces changements environnementaux et l'évolution de la vie eucaryote à travers une étude biogéochimique. La biogéochimie est l'étude des activités biologiques dans la géosphère, telles que celles intervenant dans les cycles des éléments chimiques (y compris les isotopes stables) et celles de production de composés carbonés caractérisant certains groups d'organismes ou taxons. La recherche des signatures paléoenvironnementales dans les roches précambriennes a été fortement facilitée par l'utilisation des biomarqueurs ou fossiles moléculaires. Ces composés, provenant des lipides biologiques (molécules avec des fonctions spécifiques dans les organismes), peuvent être reliés à des taxons spécifiques ou à des voies métaboliques. La transformation d'un biolipide en fossile moléculaire intervient lorsque des restes organiques déposés dans un substrat subissent un enfouissement et une augmentation de la pression (diagenèse). Ce processus mène à la formation de kérogène, un grand agrégat chimique de matière organique insoluble dans des solvants organiques, et de bitume ou fraction soluble (extractible) de la matière organique. L'analyse intégrée du kérogène et du bitume fournit des indications précieuses pour les reconstitutions paléoenvironnementales. Des conditions paléoenvironnementales ont ainsi été déterminées pour une plateforme marine Ediacarienne située dans la partie sud-américaine du bloc occidental du paléocontinent Gondwana. Les séquences sédimentaires étudiées appartiennent au même bassin qui s'étend de la ceinture du Paraguay (Groupe Corumbâ, Brésil) au craton du Rio de la Plata (Groupes Arroyo del Soldado, Uruguay et Sierras Bayas, Argentina). Nous nous sommes intéressés aux isotopes stables de carbonates et de la matière organique associée (kérogène et bitume), aux éléments majeurs et traces, ainsi qu'aux biomarqueurs caractérisant ces roches. Les résultats de cette dissertation suggèrent qu'au cours de l'Édiacarien, suite aux glaciations néoprotérozoïques dans le bloc occidental du Gondwana, l'océan était stratifié en zones spécifiques d'eaux riches en sulfures et dépourvues d'oxygène (euxiniques). L'association d'un océan stratifié et de l'apparition de la vie animale est en accord avec le modèle stipulant que l'évolution de la vie est associée à une meilleure oxygénation des environnements de surface. Les excursions isotopiques (tendance à des valeurs positives ou négatives) en constante fluctuation pour le carbone et très positives pour le soufre des sulfures, l'enrichissement en éléments trace et la présence de certains composés (e.g. gammacerane; Pr/Ph et Ph/«-Ci8 en basse proportion) conjugués aux observations sédimentologiques et paléontologiques des différents profils étudiés indiquent que la chimie de l'océan était fortement contrôlée par la disponibilité d'oxygène, avec des eaux modérément oxygénées en surface et euxiniques en profondeur pour la plupart du Néoprotérozoïque.

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Anergic T cells display a marked decrease in their ability to produce IL-2 and to proliferate in the presence of an appropriate antigenic signal. Two nonmutually exclusive classes of models have been proposed to explain the persistence of T cell anergy in vivo. While some reports indicate that anergic T cells have intrinsic defects in signaling pathways or transcriptional activities, other studies suggest that anergy is maintained by environmental "suppressor" factors such as cytokines or Abs. To distinguish between these conflicting hypotheses, we employed the well-characterized bacterial superantigen model system to evaluate in vivo the ability of a trace population of adoptively transferred naive or anergized T cells to proliferate in a naive vs anergic environment upon subsequent challenge. Our data clearly demonstrate that bacterial superantigen-induced T cell anergy is cell autonomous and independent of environmental factors.

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To develop the understanding of innovation processes conceptualized in terms of asso- ciation through the "sociology of translation" (cf. actor-network theory) studies, this article analyses innovation processes in terms of dissociation and detachment mechanisms, exami- ning innovation through "withdrawal;" that is, innovation based on reducing or withdrawing use of a practice-"subtracting," "detaching"-a given artefact. Specifically, it focuses on the shift to farming techniques that have eliminated ploughing, bringing to light four major mechanisms constitutive of dissociation: centrifugal association; making entities and asso- ciations visible; making other entities and associations invisible; bringing together or "asso- ciating" new entities. The study helps refine our understanding of the detachment processes at work in innovation, shedding light in this particular case on transfers between public research institutes, industrial companies, farmers and citizens seeking to develop new farm production models.