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In this article, gain errors in current sensing for highly dynamic three-phase drives with three current sensor measurements are compensated without the aid of the machine plant model. As three current sensors are used, redundant information from the neutral current measurement is extracted by constructing its mathematical relation with the measured time-varying $dq$ current. The proposed method compensates for nonsymmetrical current sensor gain errors even in the presence of offset errors. A recursive sliding window least square method is proposed to minimize the computation effort such that the method is suitable to be applied online. It does not incorporate a low-pass filter or averaging method based on electrical speed, making it suitable for highly dynamic applications. It is able to be applied in any three-phase ac machine, as the machine plant is not considered. Analysis, simulation, and experimental results obtained from the hardware prototype by mimicking the actual application of high-precision mechatronics demonstrate the validity of the proposed method.

[Display omitted] • This article for the first time provides a critical review of the AMCs developed by cold spraying. • A summary of composite powder preparation, CS deposition behavior, microstructure, and properties has been made. • It reports the relevant research progress on post-treatments of the AMCs for CS additive manufacturing applications. • The challenges and perspectives on the fabrication of advanced AMCs by CS are addressed. Cold spraying (CS), or cold gas dynamic spray (CGDS), is an emerging solid-state powder deposition process, allowing fast and mass production and restoration of metallic components. CS of metal matrix composites (MMCs) has attracted increasing attention from academia and industry over the last decades, especially in the area of Al matrix composites (AMCs), which have demonstrated a high potential for applications in aerospace, automotive, and electronics industries. This article aims to summarize the recent development of CS-processed AMCs in terms of composite powder preparation, deposition processing, microstructure evolution, mechanical and corrosion properties. Furthermore, this review also reports the relevant research progress with the focus on post-treatments of the AMCs for CS additive manufacturing applications including heat treatment, hot rolling, and friction stir processing. Finally, the challenges and perspectives on the fabrication of advanced AMCs by CS are addressed. [ABSTRACT FROM AUTHOR]

The Weddell Gyre (WG) is one of the main oceanographic features of the Southern Ocean south of the Antarctic Circumpolar Current which plays an influential role in global ocean circulation as well as gas exchange with the atmosphere. We review the state‐of‐the art knowledge concerning the WG from an interdisciplinary perspective, uncovering critical aspects needed to understand this system's role in shaping the future evolution of oceanic heat and carbon uptake over the next decades. The main limitations in our knowledge are related to the conditions in this extreme and remote environment, where the polar night, very low air temperatures, and presence of sea ice year‐round hamper field and remotely sensed measurements. We highlight the importance of winter and under‐ice conditions in the southern WG, the role that new technology will play to overcome present‐day sampling limitations, the importance of the WG connectivity to the low‐latitude oceans and atmosphere, and the expected intensification of the WG circulation as the westerly winds intensify. Greater international cooperation is needed to define key sampling locations that can be visited by any research vessel in the region. Existing transects sampled since the 1980s along the Prime Meridian and along an East‐West section at ~62°S should be maintained with regularity to provide answers to the relevant questions. This approach will provide long‐term data to determine trends and will improve representation of processes for regional, Antarctic‐wide, and global modeling efforts—thereby enhancing predictions of the WG in global ocean circulation and climate. The Weddell Gyre is one of the main oceanographic features in the ocean surrounding Antarctica, the Southern Ocean. Although located far from other continents, this polar region affects the planet through the exchange of gases between frigid ocean waters and the atmosphere, regulating oxygen and carbon dioxide farther north. Studying the Weddell Gyre is challenging, as sea ice covers the ocean surface year around, restricting access by research ships and sensing of ocean surface from satellites. New technology is now available to avoid past limitations, autonomous underwater vehicles, instruments flown by planes, and floats instrumented with sea‐ice detection. Only through international collaboration can we obtain adequate data to populate environmental models and study key areas in the gyre or hot spots. In this review we identify the missing links in our knowledge of the gyre, proposing research to address those questions. Three aspects are critical to understanding the processes that drive the gyre's oceanography, ice, geology, chemistry, and biology: winter and under‐ice conditions that set the stage for the evolution of physics, ice, and biogeochemistry; exchange of water, material, and energy (or heat) with lower latitudes; and intensification of the clockwise circulation of the gyre with changes in winds. Major research priorities to advance understanding of the Weddell Gyre are identified and justified against current knowledgeInterdisciplinary approaches are needed to support system science research of the Weddell Gyre and promote collaborative projectsWinter conditions, connectivity to lower latitudes, and intensification of the gyre are the main interdisciplinary priorities

In the tropical Pacific, weak ventilation and intense microbial respiration at depth give rise to a low dissolved oxygen (O2) environment that is thought to be ventilated primarily by the equatorial current system (ECS). The role of mesoscale eddies and vertical mixing as potential pathways of O2supply in this region, however, remains poorly known due to sparse observations and coarse model resolution. Using an eddy resolving simulation of ocean circulation and biogeochemistry, we assess the contribution of these processes to the O2budget balance and find that vertical mixing of O2, which is modulated by the surface wind speed and the vertical shear of the eddying currents, contributes substantially to the replenishment of O2in the upper equatorial Pacific thermocline, complementing the advective supply of O2by the ECS and meridional circulation at depth. These transport processes vary seasonally in conjunction with the wind: mixing of O2into the upper thermocline is strongest during boreal summer and fall when the vertical shear and eddy kinetic energy are intensified. The relationship between eddy activity and the downward mixing of O2arises from the modulation of equatorial turbulence by Tropical Instability Waves via their impacts on the vertical shear. This interaction of processes across scales sustains a local pathway of O2delivery into the equatorial Pacific interior and highlights the need for adequate observations and models of turbulent mixing and mesoscale processes for understanding and predicting the fate of the tropical Pacific O2content in a warmer and more stratified ocean. The eastern tropical Pacific interior is an O2deficient environment, due to intense O2consumption by microbial communities that is not vigorously replenished by ocean circulation at depth. In this study, we use a high resolution simulation of ocean circulation and biogeochemistry to understand the role of finer scale processes such as turbulence and eddies in injecting O2locally. We find that mixing due to turbulence along the equator supplies a key portion of O2into the ocean by exchanging waters between the well‐aerated mixed layer near the surface and the ocean's interior where O2falls precipitously with depth. We also find that this mixing varies considerably with the seasons. This annual cycle in mixing arises from the seasonal variability in wind stress and the passage of eddies, which amplify turbulence through their influence on the subsurface currents along the equator, and represents a previously unexplored but potentially important route of O2delivery into the ocean's interior. As the upper ocean warms and becomes less dense, the ocean's O2content is expected to decrease, and thus observing and accurately modeling these O2pathways will be crucial to monitoring how marine ecosystem habitats will shift in a warmer climate. Mesoscale‐resolving ocean biogeochemistry simulations show vertical mixing is a key source of oxygen to the equatorial Pacific thermoclineThe supply of oxygen by advection and vertical mixing is strongly seasonal and is driven by seasonal variability in the windThe vertical mixing of oxygen is modulated by the wind stress and mesoscale eddy impacts on equatorial shear‐driven turbulence Mesoscale‐resolving ocean biogeochemistry simulations show vertical mixing is a key source of oxygen to the equatorial Pacific thermocline The supply of oxygen by advection and vertical mixing is strongly seasonal and is driven by seasonal variability in the wind The vertical mixing of oxygen is modulated by the wind stress and mesoscale eddy impacts on equatorial shear‐driven turbulence

Cold spray processing appears to be a highly promising manufacturing process for coils for high field magnet. Dense and sizable material can be obtained characterized by high mechanical properties and high electrical conductivity thanks to the chamber of deposition under helium atmosphere. A low oxygen content material is obtained and the tensile and conductivity tests highlight the significance of the thermal treatment for the manufacturing process optimization.

The spatial correlation scales of oceanic dissolved inorganic carbon, heat content, and carbon and heat exchanges with the atmosphere are estimated from a realistic numerical simulation of the Southern Ocean. Biases in the model are assessed by comparing the simulated sea surface height and temperature scales to those derived from optimally interpolated satellite measurements. While these products do not resolve all ocean scales, they are representative of the climate scale variability we aim to estimate. Results show that constraining the carbon and heat inventory between 35°S and 70°S on time‐scales longer than 90 days requires approximately 100 optimally spaced measurement platforms: approximately one platform every 20° longitude by 6° latitude. Carbon flux has slightly longer zonal scales, and requires a coverage of approximately 30° by 6°. Heat flux has much longer scales, and thus a platform distribution of approximately 90° by 10° would be sufficient. Fluxes, however, have significant subseasonal variability. For all fields, and especially fluxes, sustained measurements in time are required to prevent aliasing of the eddy signals into the longer climate scale signals. Our results imply a minimum of 100 biogeochemical‐Argo floats are required to monitor the Southern Ocean carbon and heat content and air‐sea exchanges on time‐scales longer than 90 days. However, an estimate of formal mapping error using the current Argo array implies that in practice even an array of 600 floats (a nominal float density of about 1 every 7° longitude by 3° latitude) will result in nonnegligible uncertainty in estimating climate signals. Spatial correlation scales of air‐sea fluxes and content of both carbon and heat are estimated to inform observational coverage requirementsOver 100 biogeochemical‐Argo floats are required to monitor the Southern Ocean carbon and heat content on time‐scales longer than 90 daysThough fluxes have longer spatial correlation scales, they have significant temporal variance at periods less than 90 days

Évaluer au travers d’une étude rétrospective, l’impact de la réalisation d’un angioscanner corps entier multi-temps pour la mise en évidence des contre-indications (CI) au prélèvement multi-organes (PMO) et dans l’amélioration de la stratégie pré-chirurgicale des prélèvements.

The upper ocean dissolved inorganic carbon (DIC) concentration is regulated by advective and diffusive transport divergence, biological processes, freshwater, and air‐sea CO2fluxes. The relative importance of these mechanisms in the Southern Ocean is uncertain, as year‐round observations in this area have been limited. We use a novel physical‐biogeochemical state estimate of the Southern Ocean to construct a closed DIC budget of the top 650 m and investigate the spatial and temporal variability of the different components of the carbon system. The dominant mechanisms of variability in upper ocean DIC depend on location and time and space scales considered. Advective transport is the most influential mechanism and governs the local DIC budget across the 10 day–5 year timescales analyzed. Diffusive effects are nearly negligible. The large‐scale transport structure is primarily set by upwelling and downwelling, though both the lateral ageostrophic and geostrophic transports are significant. In the Antarctic Circumpolar Current, the carbon budget components are also influenced by the presence of topography and biological hot spots. In the subtropics, evaporation and air‐sea CO2flux primarily balances the sink due to biological production and advective transport. Finally, in the subpolar region sea ice processes, which change the seawater volume and thus the DIC concentration, compensate the large impact of the advective transport and modulate the timing of biological activity and air‐sea CO2flux. The carbon budget in the Southern Ocean is analyzed using a physical‐biogeochemical state estimate for the years 2008–2012The dissolved inorganic carbon budget is dominated by variability in the overturning circulationTemporal variability is enhanced near topography and fronts

A Biogeochemical Southern Ocean State Estimate (B‐SOSE) is introduced that includes carbon and oxygen fields as well as nutrient cycles. The state estimate is constrained with observations while maintaining closed budgets and obeying dynamical and thermodynamic balances. Observations from profiling floats, shipboard data, underway measurements, and satellites are used for assimilation. The years 2008–2012 are chosen due to the relative abundance of oxygen observations from Argo floats during this time. The skill of the state estimate at fitting the data is assessed. The agreement is best for fields that are constrained with the most observations, such as surface pCO2in Drake Passage (44% of the variance captured) and oxygen profiles (over 60% of the variance captured at 200 and 1000 m). The validity of adjoint method optimization for coupled physical‐biogeochemical state estimation is demonstrated with a series of gradient check experiments. The method is shown to be mature and ready to synthesize in situ biogeochemical observations as they become more available. Documenting the B‐SOSE configuration and diagnosing the strengths and weaknesses of the solution informs usage of this product as both a climate baseline and as a way to test hypotheses. Transport of Intermediate Waters across 32°S supplies significant amounts of nitrate to the Atlantic Ocean (5.57 ± 2.94 Tmol yr−1) and Indian Ocean (5.09 ± 3.06 Tmol yr−1), but much less nitrate reaches the Pacific Ocean (1.78 ± 1.91 Tmol yr−1). Estimates of air‐sea carbon dioxide fluxes south of 50°S suggest a mean uptake of 0.18 Pg C/yr for the time period analyzed. A biogeochemical state estimate of the Southern Ocean is produced for 2008–2012The estimate captures the variability of Drake Passage pCO2and oxygen profiles from Argo floatsValidity of the adjoint method for the coupled model is demonstrated through sensitivity experiments

A state estimate of the tropical Pacific Ocean is used to analyze regional volume, temperature, and salinity budgets during 2014–2018. The simulated ocean state is constrained by both model dynamics and assimilated observations. Comparisons with independent mooring data show that the state estimate is consistent with the observed variability in temperature and velocity. Budgets are analyzed between 5°S and 5°N in the upper 300 m, inside a box defined to represent the central and eastern equatorial Pacific. Transports through the faces of this box are quantified to understand the processes responsible for variability in box‐mean properties. Vertical mixing across 300 m is negligible; temperature and salinity tendencies are balanced by surface fluxes and advective divergence, which is decomposed into geostrophic and ageostrophic components. The onset and recovery of the 2015/2016 El Niño event is found to be dominated by anomalous surface fluxes and horizontal advection. During the onset phase, weaker trade winds cause the shallow meridional overturning circulation to slow down, which reduces the poleward transport of heat and leads to upper ocean warming. Anomalous precipitation and advection of fresh water from the western Pacific drive the net freshening of the region. Relaxation from El Niño conditions is dominated by wind‐driven meridional advection at 5°N. As the meridional advection regains strength, Ekman advection efficiently exports the warm, fresh surface water out of the equatorial region. Quantifying the heat and salt transport changes in response to wind variability strengthens our understanding of global ocean heat transport. We have combined observations and an ocean model to produce an estimate of the tropical Pacific Ocean properties. Of particular interest are changes to the upper‐ocean temperature and salinity over the period 2014–2018. The largest changes occur in the central and eastern equatorial Pacific, and to diagnose the causes we define an analysis box representative of that region. Transports through five faces of this box (the sixth face is a land boundary) are diagnosed to understand the processes responsible for variability in box‐average properties. We examine the cooling and freshening that occurs during the El Niño event of 2015/2016. The region is typically characterized by a near surface poleward flow away from the equator and a compensating flow toward the equator from below. This circulation is wind driven and slows down due to changing winds associated with the El Niño. When the winds return to their average state, currents are re‐invigorated, leading to the dissipation of El Niño conditions. This paper focuses on determining the size and timing of these processes. A data‐assimilating model of tropical Pacific Ocean state is validated against independent mooring observationsTemperature, salinity, and volume budgets are quantified during the onset and recovery of the 2015/2016 El NiñoSurface fluxes and horizontal advection are the main drivers of regional property changes A data‐assimilating model of tropical Pacific Ocean state is validated against independent mooring observations Temperature, salinity, and volume budgets are quantified during the onset and recovery of the 2015/2016 El Niño Surface fluxes and horizontal advection are the main drivers of regional property changes

Ocean acidification has potentially large impacts on calcifying organisms and ecosystems. Argo floats equipped with biogeochemical (BGC) sensors have been continuously measuring Southern Ocean pH since 2014. These BGC‐Argo floats were deployed as part of the Southern Ocean Carbon and Climate Observations and Modeling project. Here we present a SOCCOM‐era Objectively Mapped pH (SOM‐pH) 2014–2019 climatology and explain the method for constructing this product. We show example SOM‐pH fields demonstrating the spatial and temporal structure of Southern Ocean pH. Comparison with previous ship‐based measurements reveals decreases in pH of up to 0.02 per decade, with a structure decaying with depth. An assessment of the trend structure reveals a pattern indicative of the meridional overturning circulation. Upwelling waters that have not been in recent contact with the atmosphere show negligible or small trends, while surface and downwelling waters that have had more exposure to the atmosphere show the strongest trends. Thus comparison of this new BGC‐Argo mapped pH estimate to historic observations allows quantifying the structure of Southern Ocean acidification. Robotic instruments that measure ocean acidity levels (pH) have been deployed in the Southern Ocean since 2014. Here we compile these observations into a map that is an estimate of the current Southern Ocean pH. This paper discusses how the map is made and gives a brief description of its features. We then compare it to pH measurements made from ships prior to 2014. Analyzing the structure of these differences in space and time reveals how the Southern Ocean is becoming more acidic. We find that there is significant structure to the changes. In general the changes are largest at the surface and become smaller at greater depth. However, there are horizontal differences. Ocean locations where winds pull up deep waters have smaller trends than regions where the winds are pushing waters down. Thus the ocean changes show a signature associated with the large‐scale circulation. We present a novel 12‐month Southern Ocean pH mapped product, made possible by the Biogeochemical‐Argo array initiated in 2014Comparing to ship‐based measurements above 1,500 m reveals a decrease in pH of up to 0.02 per decadepH changes are widespread with varying magnitudes reflecting the pattern of the meridional overturning circulation We present a novel 12‐month Southern Ocean pH mapped product, made possible by the Biogeochemical‐Argo array initiated in 2014 Comparing to ship‐based measurements above 1,500 m reveals a decrease in pH of up to 0.02 per decade pH changes are widespread with varying magnitudes reflecting the pattern of the meridional overturning circulation

Laser-matter interaction is commonly described regarding three main factors: laser beam, materials and environment. Conversion of absorbed energy via collision process into heat is the most important effect that occurs during laser interaction. Short-pulsed laser beam induces fast transition from the overheated liquid to a mixture of vapor and drops which allows the ablation of micrometric layers. Specific patterns can then be achieved using scanning and automation technology also called laser texturing. New materials with specific properties such as endurance life and/or lower environmental impact attract emerging technologies such as thermal spraying. However, adhesive bond strengths have to be high enough to play a key role in surface properties. A clean surface to enhance mechanical interlocking is a key element. Mechanical and physico-chemical bond strength for thick coatings elaborated by thermal spray process can then be developed using laser. The aim of the present paper is to show the potential of such emerging treatments through new results using various thermal spray processes (thermal spraying as well as cold spraying). Metal or organic materials were investigated implementing various powders.

La mise en forme par projection thermique consiste à réaliser un ou plusieurs dépôts d'épaisseurs variables à la surface d'un mandrin sacrificiel présentant la forme complémentaire de la pièce à obtenir. Ce mandrin est ensuite éliminé pour libérer la structure constituée uniquement du ou des dépôts. Les caractéristiques de plusieurs matériaux métalliques présentant un intérêt majeur pour une mise en forme par projection thermique sous basse pression (VPS : Vacuum Plasma Spraying) ont été étudiées : à savoir les superalliages Astroloy (NK 17 CDAT) et Inconel 625 (NC 22 DNb), le TA6V (Ti-6Al-4V) et le NARloy-Z (désignation US de l'alliage Cu Ag 3 Zr 0.5). Il ressort de cette étude que des dépôts épais (de 1 à 20 mm d'épaisseur) à caractéristiques mécaniques se rapprochant de celles des matériaux forgés ou MDP peuvent être obtenus. Ces matériaux sont recristallisées directement après projection selon la température d'élaboration ou après un traitement thermique. Leur structure est principalement caractérisée par une porosité faible, voisine dans la plupart des cas de 1%, et par une taille de grain très fine. L'étude des propriétés mécaniques révèle des contraintes à rupture élevées mais une certaine perte de ductilité, en particulier à haute température par rapport aux matériaux standards équivalents. L'assemblage de matériaux VPS sur des matériaux forgés a été étudié par des tests de traction-adhérence dérivés de ceux indiqués par la norme ASTM 633-79. L'ensemble des résultats obtenus à ce jour montre que les perspectives de la mise en forme par projection thermique sont prometteuses étant données la qualité, la diversité et la vitesse de réalisation des dépôts. Cette technique permet de plus la réalisation de structures multicouches avec la possibilité de réaliser des interfaces à gradient de composition.

Les concepteurs privilégient de plus en plus l’emploi de structures à parois minces, entraînant des pertes conséquentes de matière entre les bruts initiaux et les pièces finies lorsque les méthodes classiques d’usinage sont employées. Par ailleurs, certains alliages nouvellement mis au point sont délicats à mettre en forme par les méthodes classiques, comme l’alliage à base de nickel NK17CDAT (Astroloy) par exemple. La conjugaison de ces deux aspects constitue le moteur du développement d’une nouvelle méthode de mise en forme utilisant la technique de projection thermique ; cette méthode peut être utilisée pour réaliser une forme complète à partir d’un support sacrificiel, ou bien permettre un complément par liaison directe avec une partie plus massive, notamment dans le cas des structures disposant de cavités.

Measurements of pH and nitrate from the Southern Ocean Carbon and Climate Observations and Modeling array of profiling floats were used to assess the ratios of dissolved inorganic carbon (DIC) and nitrate (NO3) uptake during the spring to summer bloom period throughout the Southern Ocean. Two hundred and forty‐three bloom periods were observed by 115 floats from 30°S to 70°S. Similar calculations were made using the Takahashi surface DIC and nitrate climatology. To separate the effects of atmospheric CO2exchange and mixing from phytoplankton uptake, the ratios of changes in DIC to nitrate of surface waters (ΔDIC/ΔNO3) were computed in the Biogeochemical Southern Ocean State Estimate (B‐SOSE) model. Phytoplankton uptake of DIC and nitrate are fixed in B‐SOSE at the Redfield Ratio (RR; 6.6 mol C/mol N). Deviations in the B‐SOSE ΔDIC/ΔNO3must be due to non‐biological effects of CO2gas exchange and mixing. ΔDIC/ΔNO3values observed by floats and in the Takahashi climatology were corrected for the non‐biological effects using B‐SOSE. The corrected, in situ biological uptake ratio (C:N) occurs at values similar to the RR, with two major exceptions. North of 40°S biological DIC uptake is observed with little or no change in nitrate giving high C:N. In the latitude band at 55°S, the Takahashi data give a low C:N value, while floats are high. This may be due to a change in CO2air‐sea exchange in this region from uptake during the Takahashi reference year of 2005 to outgassing of CO2during the years sampled by floats. Phytoplankton take up dissolved inorganic carbon (DIC) and nitrate as they grow. This results in a decrease in DIC and nitrate during the spring through summer bloom periods each year. The ratio of DIC to nitrate uptake is typically near 6.6 mol C/mol N, a value termed the Redfield Ratio (RR). Here, we used sensor data from an array of profiling floats deployed by the Southern Ocean Carbon and Climate Observations and Modeling program in the Southern Ocean to examine the ratio of C:N uptake by phytoplankton during 243 bloom periods from October through February. We find uptake occurred at values near the RR throughout the Southern Ocean, with two exceptions. North of 40°S, C:N ratios exceed the Redfield value, most likely due to phytoplankton production of a gel‐like organic matter deficient in nitrogen. Near 55°S in the Antarctic Southern Zone, an apparent increase in the C:N ratio over the past decade may reflect a change from an air‐sea flux of CO2into the ocean to a flux out of the ocean. Carbon:nitrate uptake ratios by phytoplankton are near the Redfield Ratio in Southern Ocean waters south of 40°SCarbon:nitrate uptake ratios north of 40°S are much higher, likely due to production of dissolved organic matter with little nitrogenA change in air‐sea CO2flux during October to February from a sink in 2005 to a source in recent years may have occurred near 55°S Carbon:nitrate uptake ratios by phytoplankton are near the Redfield Ratio in Southern Ocean waters south of 40°S Carbon:nitrate uptake ratios north of 40°S are much higher, likely due to production of dissolved organic matter with little nitrogen A change in air‐sea CO2flux during October to February from a sink in 2005 to a source in recent years may have occurred near 55°S

Thermal spraying is a widely used technology for industrial applications to provide coatings that improve the surface characteristics. According to the specificities of processes (APS, VPS, flame, electric arc), any kind of material can be sprayed. Among materials, ceramic coatings present several interesting aspects such as wear resistance, corrosion protection as well as thermal or electrical insulation; particularly alumina coatings which appear as the most commonly used. From all spraying processes, atmospheric plasma spraying (APS) is a rather well-established process but some others can also be used with a lower economical impact such as the flame technology. The aim of this study was to analyze the alumina coating properties according to the technology employed such as APS or wire flame spraying using the Rokide™ and the Master Jet® guns. After micrographic analyses by SEM, physical and mechanical properties were measured considering the thermal conductivity and the hardness.

Background: Low‐molecular‐weight heparins (LMWHs), derived from unfractionated heparin (UFH) by different depolymerization procedures, vary in both their relative abilities to enhance the inhibition of FXa (anti‐FXa) and thrombin (anti‐FIIa), and in their physicochemical properties. Objective: We aimed to profile the inhibition of thrombin generation induced by bemiparin, enoxaparin, nadroparin, dalteparin and tinzaparin in platelet‐rich plasma (PRP), and to compare them with UFH and fondaparinux (a synthetic pentasaccharide that specifically enhances FXa inhibition). Methods: Different LMWHs, UFH or fondaparinux were added to normal PRP. Thereafter, tissue factor‐triggered thrombin generation was assessed using the Thrombogram–Thrombinoscope® assay. Results: At equivalent anti‐FIIa activity concentrations, LMWHs and UFH exhibited similar inhibitory effects upon thrombin generation. However, when used at equivalent anti‐FXa activity concentrations, tinzaparin was significantly more active than the other LMWHs at inhibiting thrombin generation, and had similar activity to that of UFH. Enoxaparin, nadroparin and dalteparin all showed similar inhibitory activities. In these experiments, bemiparin exhibited the lowest inhibitory effect on thrombin generation of all the LMWHs. At 0.1 μg mL–1(0.093 anti‐FXa IU mL–1), fondaparinux inhibited the rate of thrombin generation by 50%. A 7‐fold higher concentration of fondaparinux was required to inhibit the endogenous thrombin potential by 50%. Conclusions: LMWHs have a variable inhibitory effect on thrombin generation in vitrowhen compared by anti‐FXa activity, but are similar when compared by their anti‐FIIa activities. The rate of thrombin generation during the propagation phase, rather than the endogenous thrombin potential, is more sensitive to the anticoagulant activity of fondaparinux and the polysaccharide chains of LMWHs possessing only anti‐FXa activity.

This paper shares ongoing research explorations into visualising and representing architecture through the limited real-estate spaces of computer screens. It proposes greater access, ‘interactivity’ and clarity in digital representations for the study, analysis and/or digital record of existing architecture by drawing on concepts and strategies – within and outside the discipline – to arrive at hybrid visualisation techniques. To illustrate some of these techniques, the paper outlines several issues in the production of hybrid media representations of the Arthur and Yvonne Boyd Education Centre. This award-winning building was designed by the 2002 Pritzker Prize-winner, Glenn Murcutt in association with Wendy Lewin and Reg Lark. It is recognised as a landmark in Australian architecture and a worthy subject of our representation experiments.

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In this work, the influence of the thermal spraying processes, atmospheric plasma spraying (APS), high velocity oxygen fuel (HVOF), and vacuum plasma spraying (VPS), on the microstructure and properties of copper coatings is discussed. The differences in microstructure, microhardness, and residual stress for each type of coating are shown. The X-ray diffraction (XRD) method is used to evaluate the mechanical anisotropical characteristics of the materials and the residual stress distribution. The particularity of this study is that the thickness of the coating is of the millimetre scale; the massive coating specimens without a substrate were obtained for XRD microelastic modulus measurements and for macrotensile measurement. Microhardness distributions have been obtained in coatings and in substrates that pass through the interface zones. It was observed that dense coatings could be obtained by industrial processes such as APS and HVOF, but they induce oxidation in the copper coating. The copper oxidation is limited in the VPS process. The elastic modulus values measured by the in situ XRD method show that the HVOF coating has more rigidity than the APS coating. HVOF and VPS copper coatings have higher microhardness values than the APS copper coating. The residual stress values are in traction in the APS, VPS, and HVOF coatings: the residual stress level in the HVOF and APS coatings is less important than that in the VPS coating. The microstructure observations show that the VPS copper coating has a recrystallised structure whereas the APS and HVOF copper coatings have a splat type structure. As a consequence, the VPS copper coating has a high Young's modulus, an important mechanical resistance, and a high elongation as compared with the other copper coatings.

The inventory and variability of oceanic dissolved inorganic carbon (DIC) is driven by the interplay of physical, chemical, and biological processes. Quantifying the spatiotemporal variability of these drivers is crucial for a mechanistic understanding of the ocean carbon sink and its future trajectory. Here, we use the Estimating the Circulation and Climate of the Ocean‐Darwin ocean biogeochemistry state estimate to generate a global‐ocean, data‐constrained DIC budget and investigate how spatial and seasonal‐to‐interannual variability in three‐dimensional circulation, air‐sea CO2flux, and biological processes have modulated the ocean sink for 1995–2018. Our results demonstrate substantial compensation between budget terms, resulting in distinct upper‐ocean carbon regimes. For example, boundary current regions have strong contributions from vertical diffusion while equatorial regions exhibit compensation between upwelling and biological processes. When integrated across the full ocean depth, the 24‐year DIC mass increase of 64 Pg C (2.7 Pg C year−1) primarily tracks the anthropogenic CO2growth rate, with biological processes providing a small contribution of 2% (1.4 Pg C). In the upper 100 m, which stores roughly 13% (8.1 Pg C) of the global increase, we find that circulation provides the largest DIC gain (6.3 Pg C year−1) and biological processes are the largest loss (8.6 Pg C year−1). Interannual variability is dominated by vertical advection in equatorial regions, with the 1997–1998 El Niño‐Southern Oscillation causing the largest year‐to‐year change in upper‐ocean DIC (2.1 Pg C). Our results provide a novel, data‐constrained framework for an improved mechanistic understanding of natural and anthropogenic perturbations to the ocean sink. The ocean has absorbed roughly 40% of fossil fuel carbon dioxide (CO2) emissions since the beginning of the industrial era. This so‐called “ocean carbon sink,” which primarily sequesters emissions in the form of dissolved inorganic carbon (DIC), plays a key role in regulating climate and mitigating global warming. However, we still lack a mechanistic understanding of how physical, chemical, and biological processes impact the ocean DIC reservoir in both space and time, and hence how the storage rates of emissions may change in the future. Here we use a global‐ocean biogeochemistry model Estimating the Circulation and Climate of the Ocean‐Darwin, which ingests both physical and biogeochemical observations to improve its accuracy, to map how ocean circulation, air‐sea CO2exchange, and marine ecosystems have modulated the combined natural and anthropogenic ocean DIC budget for 1995–2018. We find that in the upper ocean, circulation provides the largest supply of DIC while biological processes drive the largest loss. Year‐to‐year changes in the ocean carbon sink are dominated by El Niño‐Southern Oscillation events in the equatorial Pacific Ocean, which then affect DIC globally. In summary, our data‐constrained, global‐ocean DIC budget constitutes a significant step forward toward understanding climate‐related changes to the ocean DIC reservoir. We evaluate the global dissolved inorganic carbon (DIC) budget for 1995–2018 using an ocean biogeochemistry state estimate Estimating the Circulation and Climate of the Ocean‐DarwinIn the upper ocean, circulation provides the largest gain of DIC and biological processes are the dominant lossInterannual variability is greatest in equatorial regions and is associated with El Niño‐Southern Oscillation We evaluate the global dissolved inorganic carbon (DIC) budget for 1995–2018 using an ocean biogeochemistry state estimate Estimating the Circulation and Climate of the Ocean‐Darwin In the upper ocean, circulation provides the largest gain of DIC and biological processes are the dominant loss Interannual variability is greatest in equatorial regions and is associated with El Niño‐Southern Oscillation

Tropical instability vortices (TIVs) have a major influence on the physics and biogeochemistry of the equatorial Pacific. Using an eddy‐resolving configuration of the Community Earth System Model (CESM‐HR) and Lagrangian particle tracking, we examine TIV impacts on the three‐dimensional structure and variability of dissolved oxygen (O2) in the upper equatorial Pacific water column. In CESM‐HR, the simulated generation and westward propagation of TIVs from boreal summer through winter lead to the seasonal oxygenation of the upper northern equatorial Pacific, exhibited as a deepening of hypoxic depth west of 120°W. TIV effects on the equatorial Pacific oxygen balance are dominated by eddy‐advection and mixing, while indirect TIV effects on O2consumption play minor roles. These advective effects reflect the transient displacements of isopycnals by eddy pumping as well as vortex transport of oxygen by eddy trapping, stirring, and subduction. TIVs influence on the upper equatorial Pacific O2distribution and variability has important implications for understanding and modeling marine ecosystem dynamics and habitats, and should be taken into consideration in designing observation networks in this region. Tropical instability vortices (TIVs) are eddies that stir and transport water masses in the equatorial Pacific. From summer through winter, vortices are generated in the eastern equatorial Pacific and propagate toward the west, causing major physical and biogeochemical changes in the upper equatorial Pacific. We examine their effects on oxygen distributions and variability in the equatorial Pacific using a global model of ocean circulation and biogeochemistry. From boreal summer through winter, TIVs oxygenate the upper ocean through a series of processes, namely their influence on upper ocean density layers and lateral and vertical water mass exchanges that lead to a temporary deepening of the oxygen minimum zones and an expansion of vertical habitable space along their paths. Our analysis demonstrates that TIVs comprise an important mechanism regulating simulated oxygen distributions in the equatorial Pacific; these important phenomena should be explored in observational campaigns and their effects should be considered in the context of improving climate models. Tropical instability vortices (TIVs) oxygenate the northern upper equatorial PacificTIVs seasonality modulates the oxygen minimum zone structure and seasonal variability of ecosystem habitable space in the equatorial PacificTIVs' oxygenation effects are dominated by eddy advective effects while biogeochemical feedbacks play a minor role Tropical instability vortices (TIVs) oxygenate the northern upper equatorial Pacific TIVs seasonality modulates the oxygen minimum zone structure and seasonal variability of ecosystem habitable space in the equatorial Pacific TIVs' oxygenation effects are dominated by eddy advective effects while biogeochemical feedbacks play a minor role

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Six cases of familial medullary thyroid carcinoma (MTC) were investigated by light and electron microscopy as well as by ultracytochemical methods. Light microscopic examination revealed multifocal C-cell proliferation in 5 subjects. These cells were mostly limited to thyroid follicles, but occasionally extended across the follicular capsule forming microscopic MTC. Electron microscopic examination showed that, in some follicles, the proliferating C-cells were still covered by a continuous layer of follicular cells, whereas in others the proliferation extended to the follicular center. C-cells were in direct contact with the colloid, and ultramicroinvasion of the follicular capsule was detected. These observations are consistent with the hypothesis that familial MTC seems to begin as multifocal C-cell proliferation, limited at first to thyroid follicles, between the capsule and the follicular epithelium. Later, the proliferation extends to the follicular center, and C-cells come in contact with the colloid, at which time an in situ carcinoma stage is reached. Some neoplastic cells invade the follicular capsule and, finally, multiple MTC appear and eventually conglomerate.

An anisoylated plasminogen streptokinase activator complex (APSAC) has been administered as a bolus intravenous injection of 30U to 14 patients with acute myocardial infarction. Systemic effects on coagulation and fibrinolysis were studied. In 1 patient, the treatment produced no biological modification, which could be explained by an increased streptokinase resistance in this patient, apparent from the sample collected before treatment. In the other patients, as expected, fibrinogen, plasminogen, α2-antiplasmin and factors V and VIIIc fell dramatically, while there was an increase in serum fibrinogen degradation product concentrations. In addition, plasma fibrin derivatives increased during APSAC therapy, both in patients who had occluded or patent coronary arteries. Discrepancies were found between methods used to measure fibrinogen: with the Ellis and Stransky method, concentrations were higher than with the Clauss method; and for plasminogen, automated methods using different analysers may give higher results in some patients.

Activated partial thromboplastin time (APTT) is the most common assay used to screen for lupus anticoagulant (LA). For some years, manufacturers have been proposing APTT reagents that were more sensitive to LA. In this study, we evaluated the sensitivity and responsiveness of 16 APTT reagents in 40 LA and 46 normal plasmas. Sensitivity was established using a 1:1 mixture of normal and LA plasma that optimized the most sensitive reagent. The same pool of normal plasma was used for the assay of mixtures and daily APTT values for the determination of ratios. The results show that new commercially available APTT reagents are more sensitive and responsive to LA. The different sensitivities of APTT reagents might be partly due to the heterogeneity of LAs and several APTT reagents should be used for LA detection. The choice of APTT reagents constitutes an important preliminary step for LA evaluation.

Gastrointestinal symptoms are known to occur in association with multiple endocrine neoplasia (MEN) type 2. Patients with the variant 2b are at special risk and show diffuse intestinal ganglioneuromatosis. Megacolon is frequently an early X-ray finding and is associated with hyperplastic ganglion cells and nerve plexuses. The unusual association of MEN type 2a with aganglionic megacolon is described in a kindred of 92 individuals. There were 15 cases of medullary thyroid carcinoma (MTC), one case each of pheochromocytoma and hyperparathyroidism, and eight cases of Hirschsprung's disease (five histologically proven). In these eight patients, the neonatal period was characterized by a delay in the passage of meconium. Three infants died from intestinal obstruction within the first 2 weeks of life. The diagnosis was missed in one girl who died despite laparotomy. Pull-through procedures were successfully performed in three other infants. The last individual suffered from constipation and several bouts of intestinal obstruction before being operated on at the age of 19. He was subsequently found to have MTC and underwent surgery, but recurrence was recently documented. The four living patients were reevaluated. Rectal manometry could not elicit internal sphincter relaxation, thus confirming the diagnosis of Hirschsprung's disease. Biopsies of the remaining colon contained normal ganglion cells and nerve fibers, thereby eliminating the possibility of aganglionosis and ganglioneuromatosis in different parts of the large bowel of the same individual. It is concluded that Hirschsprung's disease might be responsible for bowel obstruction in MEN type 2. In familial cases of aganglionic bowel, the possibility of MEN should be ruled out by family history and appropriate testing.

Abstract. Two sisters with Carpenter's syndrome and empty sella have been evaluated for pituitary function. The TRH injection brought a normal response of TSH and prolactin. There were no change in FSH and LH, but a paradoxical increase of growth hormone and cortisol. The injection of LRH brought a normal response of FSH and LH, no change in TSH and cortisol values and a paradoxical increase in prolactin and growth hormone.

Gastrointestinal symptoms are known to occur in association with multiple endocrine neoplasia (MEN) type 2. Patients with the variant 2b are at special risk and show diffuse intestinal ganglioneuromatosis. Megacolon is frequently an early X-ray finding and is associated with hyperplastic ganglion cells and nerve plexuses. The unusual association of MEN type 2a with aganglionic megacolon is described in a kindred of 92 individuals. There were 15 cases of medullary thyroid carcinoma (MTC), one case each of pheochromocytoma and hyperparathyroidism, and eight cases of Hirschsprung's disease (five histologically proven). In these eight patients, the neonatal period was characterized by a delay in the passage of meconium. Three infants died from intestinal obstruction within the first 2 weeks of life. The diagnosis was missed in one girl who died despite laparotomy. Pull-through procedures were successfully performed in three other infants. The last individual suffered from constipation and several bouts of intestinal obstruction before being operated on at the age of 19. He was subsequently found to have MTC and underwent surgery, but recurrence was recently documented. The four living patients were reevaluated. Rectal manometry could not elicit internal sphincter relaxation, thus confirming the diagnosis of Hirschsprung's disease. Biopsies of the remaining colon contained normal ganglion cells and nerve fibers, thereby eliminating the possibility of aganglionosis and ganglioneuromatosis in different parts of the large bowel of the same individual. It is concluded that Hirschsprung's disease might be responsible for bowel obstruction in MEN type 2. In familial cases of aganglionic bowel, the possibility of MEN should be ruled out by family history and appropriate testing.

Two doses of halazepam, 20 and 40 mg, were compared to diazepam 5 mg and placebo in this double-blind, parallel experiment. The medications were administered thrice daily during the first 3 days, and twice daily during the following 11 days. Their effects were measured on the tandem walk and manual dexterity of 59 elderly female subjects. Most volunteers had some walking difficulty prior to the study and 21 suffered from some illness. With the higher dose of halazepam a statistically and clinically significant impairment of motor coordination was observed. Halazepam 40 mg, at the regimen above mentioned, should therefore not be used in elderly persons. This is substantiated by the results on all pertinent variables: tandem walk, manual dexterity, side effects and compliance to the drug regimen; indeed only 5 subjects out of 15 could tolerate halazepam 40 mg twice daily. With the manual dexterity test, significant effects of diazepam 5 mg and halazepam 20 mg were also observed. Furthermore, this test as well as the analysis of the side effects, shows that the lower dose of halazepam is well tolerated when compared to diazepam 5 mg.

Recent clinical investigations have suggested that dietary protein intake may modulate the progression of diabetic nephropathy and influence glycaemic control in Type 2 (non-insulin-dependent) diabetes mellitus. Twelve normotensive Type 2 diabetic patients with microalbuminuria took part in a randomized cross-over trial of a 3-week high protein diet (2.0 g/kg desirable weight per day) and a 3-week moderate protein diet (0.8 g/kg desirable weight per day) to test the simultaneous effect of protein intake modulation on glycaemic control and renal function. Both diets were isoenergetic and the moderate protein diet was supplemented with calcium and phosphate. Renal function and glycaemic control were evaluated at the beginning and at the end of each diet. The moderate protein diet reduced the urinary albumin excretion rate, glomerular filtration rate, creatinine clearance, and proteinuria without adversely affecting glycaemic control; fasting glycaemia and the ratio of fructosamine to proteins were significantly reduced. The high protein diet induced similar improvements in glycaemic control but small changes in renal function.

Thrombocytopenia is a common condition in distressed newborns, but little is known about thrombocytopenia in an unselected cohort of neonates. In an attempt to address this issue, a multicenter prospective study was conducted in three obstetrical wards of AP-HP in Paris. We found the frequency of neonatal thrombocytopenia (<150 × 109/L) to approximate 0.9% (48 of 5,632 appropriate samples). An immune mechanism was likely to be the cause of thrombocytopenia in 10 of the 33 cases studied, implying an incidence of 0.3% of immune neonatal thrombocytopenia in the general population. The frequency of alloimmune thrombocytopenia was 1.5/1,000 liveborn neonates, and 1/1,000 when considering anti–HPA-1a allo-immunization. Because thrombocytopenia, whatever its cause, was often silent and delayed, it appears that the only way to detect neonatal thrombocytopenia in time to prevent its potential disastrous complications would be to perform a systematic neonatal blood sampling for platelet count. All cases of ascertained thrombocytopenia should then be screened for an immune mechanism to enable early detection of autoimmune diseases in mothers and careful monitoring of subsequent pregnancies and deliveries, leading to appropriate prevention of potential severe deleterious effects in the offspring.

Elevated levels of plasma uric acid have been linked to increased risk of cardiovascular diseases and their complications. As dairy proteins have been found to decrease plasma uric acid without increasing glomerular filtration rate, a sample of postmenopausal women living in Montreal was studied to investigate the nature of this relationship. Participants (158 Roman Catholic nuns) were randomly assigned to one of two test diets for a period of four weeks: the dairy foods group (n=81) consumed approximately 30 grams of dairy protein daily and the dairy-free diet group (n=77) ate no dairy foods at all. Subjects completed two one-day food records, a core questionnaire and a dairy foods diet history; blood specimens were obtained, and blood pressure, height and weight were measured. Average nutrient intakes differed as a consequence of the test diets, with significantly greater intakes of protein, fat, saturated fat, monounsaturated fat, potassium and calcium (p<0.01) in the dairy group after the study period, and lower dietary levels of protein, cholesterol, calcium and retinol (p<0.01) in the dairy-free group. Plasma uric acid was unchanged after the dietary intervention in the dairy group, but increased by 7.8 µmol/1 (p=0.03) in subjects on the dairy-free diet; however, diastolic blood pressure decreased in response to calcium (ß=-22.9, SE=10.0,p=0.02) among those whose diet included dairy foods. The study results suggest that proteins of dairy origin may play a role in stabilising or lowering plasma uric acid, and that calcium or other components found in milk products may also reduce diastolic blood pressure. While these findings have implications for dietary prevention to decrease cardiovascular risk in postmenopausal women, further investigations should examine these mechanisms in men over the age of 50 to ascertain whether a similar response would occur.

Visual behaviour of pistol shooters of various levels of experience was studied using a video-oculometric technique to record the direction of gaze. A spatio-temporal analysis of the fixation patterns of subjects (five international pistol shooters and five international pentathletes) found that patterns were related to the level of skill. The pentathletes, whose level was lower, positioned their gaze on the weapon sight and visually followed the movement of the weapon towards the target. The pistol shooters appeared to use negative feedback in bringing up their weapons, so reducing the angle formed by the weapon, target and gaze. They fixed their gaze directly on the target or between the target and the weapon. Observations showed a prolonged time of attack (x = 1.107 s vs 0.558 s; P <0.001) and a shorter stabilization time (x=0.714s vs 1.216 s; P <0.001) for the most expert shooters. The psycho-physiological mechanisms which were the basis of these patterns and the reasons why shooters chose them are discussed.

Thrombocytopenia is a common condition in distressed newborns, but little is known about thrombocytopenia in an unselected cohort of neonates. In an attempt to address this issue, a multicenter prospective study was conducted in three obstetrical wards of AP-HP in Paris. We found the frequency of neonatal thrombocytopenia (<150 × 109/L) to approximate 0.9% (48 of 5,632 appropriate samples). An immune mechanism was likely to be the cause of thrombocytopenia in 10 of the 33 cases studied, implying an incidence of 0.3% of immune neonatal thrombocytopenia in the general population. The frequency of alloimmune thrombocytopenia was 1.5/1,000 liveborn neonates, and 1/1,000 when considering anti–HPA-1a allo-immunization. Because thrombocytopenia, whatever its cause, was often silent and delayed, it appears that the only way to detect neonatal thrombocytopenia in time to prevent its potential disastrous complications would be to perform a systematic neonatal blood sampling for platelet count. All cases of ascertained thrombocytopenia should then be screened for an immune mechanism to enable early detection of autoimmune diseases in mothers and careful monitoring of subsequent pregnancies and deliveries, leading to appropriate prevention of potential severe deleterious effects in the offspring.

Ethanol increases and prolongs the hyperlipemia following a fat load (corn oil). This does not seem to be due to changes in fat absorption or removal; studies done in man failed to show any effect of ethanol (in vivo and in vitro) on the postheparin lipoprotein-lipase activity. The data presented here and data from the literature suggest the importance of many mechanisms in the explanation of the marked hyperlipemia seen after the ingestion of corn oil plus ethanol: 1) an increased amount of NEFA brought to the liver (from hydrolyzed corn oil and mobilized fat stores), 2) an increased percentage of incorporation of NEFA into triglycerides, 3) an increased synthesis and decreased oxidation of fatty acid by the liver, 4) an increased amount of α-glycerophosphate, and 5) an increased release of lipoprotein from the liver.

After a complete fast of 5–8 days in 30 obese females, there were no changes in the xylose test. The 131I oleic acid test showed only minimal changes that could be explained by the decreased blood volume during fasting. The 131I triolein absorption test gave a lower blood radioactivity curve during fasting. There was a delay of many hours in the opacification of the gallbladder after iopanoic acid was ingested compared to the control test. Bile stasis is the proposed explanation for this finding.

After a complete fast of 5–8 days in 30 obese females, there were no changes in the xylose test. The 131I oleic acid test showed only minimal changes that could be explained by the decreased blood volume during fasting. The 131I triolein absorption test gave a lower blood radioactivity curve during fasting. There was a delay of many hours in the opacification of the gallbladder after iopanoic acid was ingested compared to the control test. Bile stasis is the proposed explanation for this finding.