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Water is a key ingredient to the potential for life, and several icy moons, such as Europa and Enceladus, are thought to harbor a dynamic subsurface ocean of liquid water. An ice probe or “cryobot” is a proposed technology to penetrate the surrounding ice shell and deliver a life-detection payload to these oceans. As the ice probe descends, it is surrounded by a thin melt film of liquid water. This paper focuses on the fluidics of the melt film for the case of a general ice probe shape, leading to a new approximate equation for the force balance constraints (validated to 0 . 4 % error by numerical model). In addition to the introduction of water by melting, the analysis allows for consideration of additional volumetric flow via a pumped jet of recirculated water. The general force balance equation is explored in more detail for the example of a cylindrical probe geometry with flat circular end caps. The thickness of the melt film below and to the side of the cylindrical probe is constrained by the force balance such that the probe typically operates in one of two asymptotic regimes, moving or stalled.

In this work, we explore two different Oscillating Heat Pipe (OHP) evaporator-condenser placement configurations, and investigate and quantify the effects on thermal performance. The proposed study focuses on two different OHP evaporator-condenser configurations with a change in adiabatic length. One of the challenges in OHP literature is the variety of experiment setups, (e.g. varying condenser, evaporator, and adiabatic lengths, heat input) which makes it difficult to compare results directly. To quantitatively compare thermal performance, a (or a set of) standardized metric(s) must be used. Therefore, we define a standardizing metric to quantify OHP’s ability to conduct heat that can be used across multiple experiments and setups. This study was conducted on an additively manufactured flat-plate AlSi10Mg OHP which has a channel diameter of 1.4 mm, 22 turns, and a plate size of 200 mm × 90 mm × 4 mm. Both the evaporator and condenser are rectangles with contact areas of 46 mm by 78 mm. The OHP was charged with R134a with a 45% filling ratio. In these tests, the location of the evaporator was fixed, while the placement of the condenser is varied such that the adiabatic length ranged between 4 mm to 94 mm. The condenser temperature was maintained between 10°C to 25°C and the heat input ranged between 20W to 50W. The results showed that a reduction in adiabatic length increased the thermal conductivity. To quantify the thermal performance, the thermal conductivities of an empty and charged OHP were determined for each placement configuration, then a thermal conductivity ratio of charged and empty OHP can be determined to quantify the improved performance. For an adiabatic length of 4 mm, we observed that the OHP’s ability to conduct heat was 40 times more effective when compared to an empty OHP. It was also observed that the OHP’s ability to conduct heat was 9 times more effective when compared to an empty OHP for an adiabatic length of 94 mm. We conclude that the area outside the evaporator-condenser that is neither heated nor cooled, called the reservoir, significantly influenced the thermal performance. The OHP with a shorter adiabatic length increased the reservoir in the condenser region which showed higher thermal performance. In this placement configuration, the reservoir essentially acted as an extension of the condenser. This is a favorable condition where the subcooled liquid slugs re-enter the condenser section which affects heat transfer drastically. Thus, the placement of the evaporator-condenser will influence OHP performance due to the reservoir and warrants future work.

Metal materials are used widely in industry for piping, as they provide desirable material properties for use in harsh environments. In this work, we explore different flexible pipe joint designs that enable fluid transport in flexible heat transfer devices. Flexible joints would allow heat transfer devices to fit in variable cooling areas. The proposed flexible joints will be 3D printed in metal with the goal of maximizing their bending angles, while minimizing volume. The objective of this research is to develop flexible pipes to connect parts involving fluid flow, and we propose three types of flexible joint designs: 1) helical coil spring, 2) torsional coil spring, and 3) serpentine structure. Then, we introduce a low-cost design process to improve these joint designs. Metal 3D printing offers increased design flexibility in comparison to traditional metal manufacturing methods. However, metal 3D printing can be labor intensive and costly, thus the number of design iterations using metal printing should be minimized during the design process. To reduce the frequency of metal prototyping, we used plastic 3D prints for rapid prototyping and evaluation. The flexible joint design considered the effects of pipe shape, pipe size, pipe diameter, free length, and total pipe length. Although mathematical models exist for the three types of flexible designs, they tend to be complex, difficult to implement, and specific to certain types of boundary conditions. In our experience, it is faster and more meaningful to perform experimental parametric studies using plastic prints due to accessibility and cost-effectiveness of plastic 3D printers. However, analytical models do offer significant insights during the design process. Thus, we developed simple analytical models for each of the three types of flexible joint designs which can be used in the initial design phase. Tests were performed to characterize the designs. Then, finite element simulations were performed for plastic prints and these simulations were validated against experimental data. We show that the results from analytical models, finite element simulations, and testing results for plastic prints are consistent, and these tools can be used to predict performance. In this paper, we discuss the following findings: 1) development of simple analytical models, including successes, limitations, and challenges; 2) the role of finite element simulations in the design process; 3) testing results from the three types of joint design; 4) quantification, interpretation, and discussion of testing results.

Objective: Adding to existing challenges in conducting clinical trials, COVID-19 has indefinitely affected modern clinical research. Decentralized clinical trials, using telemedicine and digital technology, may prove critical to the future of clinical development. This type of methodology in psychiatric trials remains largely unexplored; therefore, we evaluated the feasibility and quality of data collection in a randomized, sham-interventional trial using fully decentralized methodology in subjects with major depressive disorder (MDD). Methods: This was a four-week, noninterventional, two-cohort, decentralized, clinical trial. Eligible adults had a diagnosis of MDD and were medically stable. Subjects in cohort 1 continued stable antidepressant and antipsychotic treatment and were randomly assigned 1:1 into assisted or unassisted groups (ie, completing assessments at home aided by mobile healthcare providers or alone using study-provided materials, respectively). Subjects in cohort 2 continued stable antidepressant treatment only or with other therapy and could choose assignment to assisted or unassisted groups. Coprimary endpoints were operational effectiveness (assessed by completion rate, subject diversity, time to study start, and subject satisfaction) and data-collection integrity (assessed by subjects’ ability to collect assessments and real-time data availability). Safety analyses included incidence of adverse events and suicidality. Results: In cohort 1, 96 subjects were screened with 31 enrolled; in cohort 2, 46 subjects were screened with 26 enrolled. Most subjects (≥81% across study groups and cohorts), and more than 80% of both cohorts, completed all assessments. No major safety concerns were encountered. Conclusions: This study demonstrated that decentralized clinical trials can be performed in patients with stable MDD. Clinical trial registration number: None; this was a noninterventional trial.

Dès le rattachement de l'Alsace à la France, la valorisation du territoire s'affirme comme l'un des objectifs majeurs de la monarchie dans la province, et pour ce faire, la maîtrise des cours d'eau est vite perçue comme essentielle. Au-delà du seul intérêt économique, l'étude des fonds de l'intendance montre qu'au XVIIIe siècle, l'ingérence du pouvoir royal dans la police des cours d'eau à travers la gestion des conflits d'usage et de la lutte contre les inondations, permet à la monarchie de légitimer son intervention, et donc par extension, l'autorité du souverain. Dans ce domaine, l'action des ingénieurs des Ponts et Chaussées est essentielle à l'action des pouvoirs administratifs. Ces derniers autant que les populations riveraines se reposent sur leur expertise et leur pratique du terrain. Toutefois, en dépit de leur intervention permanente, la portée des mesures reste cantonnée au niveau local et les compromis imposés par la réalité tant environnementale que politique de la province sont nombreux, conduisant à une administration originale, sans pour autant être exceptionnelle, du réseau hydrographique alsacien Following the conquest of Alsace and its integration to the French kingdom between 1648 and 1697, the valuation of this new territory became one of the main objectives of the Monarchy's representatives. In order to do so, waterway control and management soon became necessary. Beyond the sole economic and military value of rivers, the study of the intendance archives shows that in the 18th century, the progressive intrusion by State agents into provincial waterway policy allows the Crown to legitimate its intervention and thus, to strengthen its authority. The role of the Ponts et Chaussées civil engineers appears essential regarding flood regulation and use conflicts. They would help the judiciary and administrative authority of the province (the intendant) to legislate, by shedding light on the technical and environmental stakes of these floods and conflicts. Their qualification was also recognized by riparian populations, who would never hesitate to call upon their technical knowledge and their field expertise. Water users and communities soon came to spontaneously seek the support of the royal administration, recognizing de facto the new sovereign power over the territory. Moreover, the French monarchy could rely upon its ability to mobilise men and money to implement its policies through taxation and forced labour. However, it also had to deal with local privileges, keep a political and social stability and adapt its policies to environmental constraints, which limited the scale of its intervention and often forced it to compromise.

Alors que l’abondance de l’hydrographie est mentionnee dans de nombreuses sources decrivant le Canada, colons et administrateurs s’accommodent des realites environnementales de la colonie. De fait, dans ses tentatives pour faciliter la circulation fluviale, l’Etat se heurte a un manque de moyens qui limite les capacites d’amenagement. Contrairement a d’autres territoires francais, il concentre son action sur les rivieres et, en depit de l’omnipresence de l’eau, il privilegie l’adaptation des pratiques plutot que la transformation du milieu. Les mesures de gestion de l’hydrographie revelent ainsi l’importance des initiatives locales et le contraste entre les volontes politiques affichees et les realisations concretes.

Two-phase mechanically pumped fluid loops have the potential to provide numerous benefits for spacecraft based applications. Here a hybrid two-phase capillary and mechanically pumped fluid loop that shows promise for spacecraft thermal control applications is analyzed and its operational limits are characterized. Data from an experimental system that incorporates a 3D printed evaporator is correlated to several models that together provide a comprehensive characterization of the system behavior. The loop performance is analyzed using pointwise as well volume-averaged governing equations and resistance network models, to predict flooding and dryout limits. Also, system-level numerical (including 3-D CFD simulations) transient and linear-response analyses are performed predicting the changing loop phase distributions and the observed time-dependent behavior. With the 3D-printed evaporator, a notably high evaporator conductance of 30 W/cm2-K and heat flux over 10 W/cm2 over large area are achieved with negligible temperature non-uniformity.

This paper presents a three-dimensional heat transfer analysis of a flat-plate oscillating heat pipe (OHP). To enhance implementation of OHPs in various applications, it is important to understand the comprehensive phenomena that include thermal diffusion in the whole structure and thermal hydraulics in the channel. We developed an OHP model that includes the effect of thermal diffusion and thermo-fluid behavior. The model was validated with experimental results of a flat-plate aluminum OHP which has a size of 200 mm × 90 mm × 3.8 mm, a channel diameter of 1.0 mm, and a turn number of 42. The effect of surface roughness in the channel and liquid film thickness on operating temperature is investigated. The relation between thermo-fluid behavior in the channel and temperature distribution of the OHP is analyzed. For aluminum OHP, the temperature difference across the thickness direction is 0.1 °C which is relatively small, whereas, the moving hot spot: local high-temperature region, is found in the planer surface. The maximum hot spot superheat temperature reached 5.4 °C for 200 W. The novelties of this paper are to develop the three-dimensional comprehensive OHP model and to reveal the combined effect of thermo-hydraulic phenomena and thermal diffusion in OHP structure.

Despite the strong societal impact of natural hazards, their documentation remains incomplete, with only a few inventories exceeding the past two centuries. Surprisingly enough, this also applies to Europe, a densely populated territory, and to floods, which along with storms is the most common and damage-causing natural hazard in this area. In addition, existing inventories have often been compiled by scientists and technicians and are used for risk management in a top-down manner, although the participation of all parties concerned has been recognized as a key factor for disaster reduction. To address this double paradox, the present article presents the regional flood risk observatory ORRION for the Alsatian region, northeastern France, and its very rich data content. Stemming from two successive interdisciplinary and transnational French-German research projects, ORRION was designed as a participative online platform where information is shared between individuals, stakeholders, engineers, and scientists. This original approach aims at maximizing knowledge capitalization and contributes to building a common knowledge base for flood risk. ORRION is organized by events including all river floods that have likely arisen from a single synoptic situation. For each event, it documents information sources, date of occurrence, causes, and consequences in terms of damage and affected river basins and municipalities. ORRION contributed toward renewing our knowledge of flood hazard and risk in the target area. Notably, here, long chronicles of floods are derived for 13 rivers, the Rhine and most of its main Alsatian tributaries, and for all Alsatian municipalities, most of them since the end of the 15th century, but over more than one millennium for the Rhine. Their main characteristics according to various typologies (seasonality, causes, severity, etc.) are analyzed. Major developments over the study period related to sources, land use, and/or climate change are identified. The advantages and limitations of the approach are discussed and the potential to expand both data exploitation and the building of common flood risk knowledge are listed.

En France, le XVIIe siècle est marqué par deux phénomènes qui concourent à modifier les rapports entre l’État et le territoire. Le premier est l’expansion des frontières du royaume, motivée par des considérations politiques et stratégiques en métropole, doublées d’un intérêt économique outre-mer. Le second est la participation grandissante de l’État dans les projets d’aménagement hydrauliques, tels que la création de nouvelles voies navigables et l’assèchement des marais. Ce mouvement de mise en valeur du réseau hydrographique visant à répondre aux impératifs de la monarchie française à l’échelle du royaume, c’est-à-dire garantir sa puissance en développant son économie et en protégeant son territoire, permet donc de situer la question suivante au cœur de cette recherche : quelle part prend la gestion de l’environnement dans l’expansion de la souveraineté française sur des espaces nouvellement agrégés en Europe et outre-Atlantique ? En quoi l’administration des cours d’eau, les atouts qu’ils représentent et les contraintes qu’ils imposent, participe-t-elle de l’intégration de ces territoires ? En s’appuyant sur les apports récents de l’histoire environnementale, la thèse propose une comparaison entre l’Alsace et la Nouvelle-France qui analyse les modalités d’appropriation des territoires nouvellement agrégés à la couronne de France, à la lumière des interactions entre les pouvoirs publics, les populations et le milieu. En tenant compte à la fois de la dimension matérielle du rapport à l’eau, mais aussi de ses dimensions culturelle, politique et sociale, l’analyse des sources produites par et pour le pouvoir royal montre que, tant lors de la conquête que pour l’administration du territoire, le réseau hydrographique est pris en compte pour répondre aux objectifs politiques, militaires et économiques de la France. La thèse met ainsi en lumière la part prise par la gestion de l’environnement dans les mécanismes d’appropriation du territoire, une part capitale dans le cas d’espaces récemment rattachés au royaume. De fait, dans sa stratégie d’expansion de sa souveraineté, l’État s’affirme comme acteur de la gestion des cours d’eau à travers une action protéiforme. Ce sont surtout les représentants du pouvoir royal dans la province et dans la colonie qui contribuent à légitimer l’action de la monarchie et à asseoir l’autorité du roi par l’encadrement des pratiques et des aménagements des cours d’eau. La capacité d’action des populations dont il faut pragmatiquement tenir compte, et les contraintes imposées par l’environnement hydrique se révèlent dans les discours et dans les mesures adoptées par le pouvoir central comme par ses relais. C’est ainsi que la perspective de l’hydro-histoire comparée, adoptée dans cette thèse pour analyser deux territoires très différents, permet de révéler le décalage entre ce qui pourrait être qualifié d’environnement perçu, sur lesquels se fondent les politiques générales et les grands projets d’aménagement, et l’environnement réel de chaque espace, dont les caractéristiques propres et les intérêts parfois contradictoires contrarient les desseins de la monarchie, poussée au compromis et à l’adaptation., In XVIIth Century France, two phenomena tend to modify the relationships between the State and the territory. The first one is the expansion of the kingdom’s borders, due to political and strategical considerations from the metropole. The second phenomenon is the ever-increasing involvement of the State into hydraulic planning, such as the creation of new waterways or the draining of swamps. This valorization of the hydrographic network aims at answering the needs of the French monarchy fort the kingdom, that is to say, to strengthen its power by developing the economy and protecting the territory. Such a trend allows us to raise the question which will be at the heart of this research: how relevant is the management of the environment to the expansion of French sovereignty on newly integrated territories, in Europe and across the Atlantic? To what extent does the management of waterways, with all their assets and constraints, pertain to the integration of said territories? Based on the recent developments of environmental history, the thesis offers to compare Alsace and New France, analyzing the ways these newly acquired territories are appropriated by the French Crown by looking at the interactions between public authorities, populations and environment. The analysis takes into account not only the material aspect of water, but also its cultural, political, social and material dimensions. Doing so, the sources provided by and for the State show that the hydrographic network is taken into account to achieve France’s political, military and economic goals, not only for the conquest, but also for the subsequent administration of territories. Thus, the thesis highlights the part played by the management of the environment in the ways the territory is handled and appropriated: This role is crucial in the case of areas recently attached to the kingdom. Indeed, through its strategy of expansion of its sovereignty, the French State asserts itself as a genuine participant in the handling of waterways, taking manifold measures. The representatives of the royal State, both in the colonies and in the province, contribute to legitimizing the actions of the monarchy and to establishing the king’s authority by controlling both the uses and the material adaptations of the waterways. The wording of the archives, and the measures taken by the central power as well as by its representatives, reveal much about the capacity of action of the populations, a pragmatic aspect that must be taken into account, but also much about the constraints imposed by the hydric environment itself. Thus, comparative hydro-history, as used in this thesis to analyze two very different territories, enables us to reveal the discrepancy between what could be called a perceived environment, upon which general politics and great layout projects are based, and a genuine environment for each area. In both territories, specific characteristics and sometimes contradicting interests go against the plans of the monarchy, therefore forcing it to compromise and adapt., Réalisé en cotutelle avec l'Université de Haute-Alsace (France)

Publie a l’occasion du bicentenaire de la Commission centrale pour la navigation du Rhin (CCNR), l’ouvrage collectif presente, en six parties de longueur inegale, l’histoire de cette structure decrite comme « la plus vieille organisation internationale contemporaine ». La premiere partie expose les conditions de mise en place de la Commission, de la structure embryonnaire napoleonienne a l’Acte de Mannheim en 1868. Suivant les changements de regime politique, elle prefigure la dimension haute...

International audience

Depuis L’intendance d’Alsace de Georges Livet, aucune etude ne s’etait attelee avec autant de minutie a etudier le processus d’integration de l’Alsace a la France au XVIIe siecle. Dans un recit quasi-chronologique, J.-P. Kintz retrace les etapes du rattachement progressif de l’Alsace au royaume de France avec un souci du detail qu’il faut saluer. Douze chapitres decrivent ce cheminement complexe. Les premiers, consacres a la guerre de Trente Ans, montrent l’ingerence francaise croissante dans...

When is led a prevention initiative concerning flood risk, the recall of old events allows just as much to act as pedagogy to legitimize the initiative. So as it is written in the information leaflet on the “Plan de Prévention des Risques d’Inondation” (PPRI):«Alsace did not know any more exceptional floods since 1910. In almost a century, the flood risk thus naturally faded of our memory”. A paradoxical assertion because the floods of 1910 are not taken into account for risk mapping. Only the recent floods (1983, 1990) are used as benchmarks. We were able to show [1] that, although legitimate as reference events, the floods of 1910 and many others had become manifestly underestimated for multiple reasons connected to the history of Alsace, or due to disorganization of the archives. Worse, these riks unawareness is shared by all the actors, causing problems of acceptance of the risk and their management, and an additional vulnerability in terms of population behavior before, during and after the crises. This is the reason why an online participative database (ORRION) has been created. the objective of this database is to inform and to share the information about floods history, in the particular context of a cross-border territory (France, Germany, Switzerland). This tool has been immediately involved into risks prevention actions (PAPI, PPRI).

Thann, entre Massif Vosgien et plaine d’Alsace, est une des premières villes du Haut-Rhin à avoir fait l’objet d’un Plan de Prévention des Risques d’Inondation (PPRI). La commune est en effet traversée par la Thur, caractérisée par des crues violentes. Pour autant, le zonage du PPRI de la Thur ne mentionne qu’une zone à risque assez réduite. Or la ville a été victime par le passé d’inondations destructrices, telles que le révèle la base de données TRANSRISK. Parmi ces événements, la crue de décembre 1947, très bien documentée, permet, à travers une approche géohistorique (contextualisation, transposition), la confrontation spatiale des zones inondées en 1947 et des zones classées inondables par le PPRI. Les résultats soulèvent de nombreuses questions quant à la qualité du zonage du PPRI qui semble pécher par erreur et par omission. Et en cas de crue centennale, les dégâts seraient catastrophiques. Si la reconstitution de 1947 offre un scénario du pire, cela peut aussi constituer une base de préparation de gestion de crise. Thann, between the Vosges Mountains and the Alsace plain, is one of the first cities of Haut-Rhin to have been concerned by a Flood Risks Prevention Plan (PPRI). The town is indeed crossed by the Thur river, characterized by violent floods. However, the zoning of the PPRI mentions only a relatively small risk area. But the city has suffered in the past from destructive floods, as it is revealed by the TRANSRISK database. Among these events, the flood of December 1947, very well documented, allows, through a geo-historical approach (contextualization, transposition), the spatial confrontation of areas flooded in 1947 and flood areas designated by the PPRI. The results raise many questions about the quality of PPRI zoning that appears to present errors and omissions. And in the case of a 100-year flood, the damage would be catastrophic. If the re-enactment of the 1947 flood features a worst case scenario, this can also be the basis for a preparation for crisis management.

Activin and inhibin, members of transforming growth factor-beta (TGFbeta) superfamily, have diverse and widespread effects within living organisms at many stages during growth and development. From the initial isolation of these growth factors based on their effects of FSH secretion, the study of these factors, as well as of the activin-binding protein follistatin, has progressed from the localization of the expression of the inhibin alpha subunit, activin betaA and betaB subunits, and activin receptors in the tissues of various organisms to the examination of activin and inhibin as autocrine and paracrine agents in cell proliferation and differentiation. The inhibitory effects on cell growth and differentiation that have been observed upon treatment of cells with activin suggest that further understanding of the bioactivity of this molecule and its characterization on a molecular level may aid in a more complete understanding of cell growth and differentiation. This minireview discusses the roles of activin, inhibin, and follistatin in the arenas of cell proliferation, differentiation, and embryogenesis, as well as the roles of these molecules in cancerous cells.

The effective thermal energy density of R134a subjected to an isobaric or isochoric process is determined and evaluated in the two-phase and supercritical regimes. The results are qualitatively extended to other fluids via the principle of corresponding states. It is shown that substantial increases in volumetric energy density can be realized in the critical region for isobaric processes. Also, for isobaric processes which utilize the full enthalpy of vaporization at a given pressure, there exists a pressure at which the volumetric energy density is a maximum. For isochoric processes (supercritical and two-phase), it is found that there is no appreciable increase in volumetric energy density over sensible liquid heat storage; the effective specific heat can be enhanced in the two-phase, isochoric regime, but only with a significant reduction in volumetric energy density.Copyright © 2013 by ASME

An alternate to the two-tank molten salt thermal energy storage system using supercritical fluids is presented. This technology can enhance the production of electrical power generation and high temperature technologies for commercial use by lowering the cost of energy storage in comparison to current state-of-the-art molten salt energy storage systems. The volumetric energy density of a single-tank supercritical fluid energy storage system is significantly higher than a two-tank molten salt energy storage system due to the high compressibilities in the supercritical state. As a result, the single-tank energy storage system design can lead to almost a factor of ten decrease in fluid costs. This paper presents results from a test performed on a 5 kWht storage tank with a naphthalene energy storage fluid as part of a small preliminary demonstration of the concept of supercritical thermal energy storage. Thermal energy is stored within naphthalene filled tubes designed to handle the temperature (500 °C) and pressure (6.9 MPa or 1000 psia) of the supercritical fluid state. The tubes are enclosed within an insulated shell heat exchanger which serves as the thermal energy storage tank. The storage tank is thermally charged by flowing air at >500 °C over the storage tube bank. Discharging the tank can provide energy to a Rankine cycle (or any other thermodynamic process) over a temperature range from 480 °C to 290 °C. Tests were performed over three stages, starting with a low temperature (200 °C) shake-out test and progressing to a high temperature single cycle test cycling between room temperature and 480 °C and concluding a two-cycle test cycling between 290 °C and 480 °C. The test results indicate a successful demonstration of high energy storage using supercritical fluids.Copyright © 2013 by ASME

Alors que l’histoire environnementale est en plein essor, son application à l’espace-temps de la Nouvelle-France reste rare en dépit de travaux susceptibles de nourrir ce champ. Cet article dresse le bilan des travaux déjà produits sur la période, insérés dans des études diachroniques plus larges ou portant plus précisément sur l’Amérique française et les espaces qui la composent, et dont le récit concerne souvent la confrontation entre les Européens et l’environnement américain et les modalités d’adaptations qui en résultent. Ce récit pourrait être précisé et nuancé en connectant la Nouvelle-France à d’autres espaces : américains, atlantiques ou français. Surtout, une approche environnementale de l’espace français en Amérique permettrait de redéfinir un certain nombre de cadres méthodologiques, spatiaux et chronologiques de l’historiographie coloniale., Although environmental history is undeniably a booming and growing branch of the field, it is still seldom applied to New France, even if some research exists that could contribute to it. This article aims at reviewing the works already released concerning the period, either incorporated in wide, diachronic studies or focusing on French America and the spaces composing it. The accounts on the latter often deal with the various ways in which Europeans worked with and adapted to the American environment. This narrative could be fleshed out and made more nuanced by connecting the environmental history of New France to other American, Atlantic or French spaces. Last but not least, the environmental approach is a way to challenge the traditional narratives of colonial history through specific methodologies and new disciplinary, geographical, and chronological boundaries.

Two methods for calibration and wavelength calculation for echelle spectrograms are discussed. The rough method employing ruler measurements on photographic enlargements has an accuracy of about 1 in 105. The accurate method using comparator measurements of Th standard lines and a computer routine has given an accuracy of 2 in 107 and promises greater precision for spectrograms obtained with modern echelle gratings.

Communication à la journée d'études Clio en carte 5 : Cartographier la frontière hier et aujourd'hui (Mulhouse, 13 novembre 2013); International audience; Le royaume de France des Capétiens était un cadre hérité, issu des partages carolingiens. En cartographier les limites est un exercice attendu dans l'historiographie, qui a fait de l'Histoire de France un double récit de la construction de l'Etat et de la conquête intérieure du pays par cet Etat central. L'arrière-plan cartographique de ce récit doit être reconsidéré. Avant le 13e siècle, en l'absence d'un Etat, quelle est la pertinence du cadre étatique ? La carte politique ne porte-t-elle pas l'illusion (téléologique) d'une continuité ? A partir du 13e siècle, un nouvel Etat se met en place. Mais où placer ses limites sur la carte ? Sont-elles judiciaires, fiscales ou militaires ? Dans la première période, le cartographe doit faire un choix entre des limites de nature différentes : les frontières les plus pertinentes ne sont pas forcément étatiques. Dans la seconde période, à une autre échelle, c'est la nature des frontières politiques elles-mêmes qui est en cause. Au final, les représentations historiographiques de la limite sont liées à celles du pays lui-même. La question de la naissance de la France ne peut pas faire l'économie d'une réflexion de méthodologie cartographique.