Planetary Science Virtual Observatory architecture

In the framework of the Europlanet-RI program, a prototype of Virtual Observatory dedicated to Planetary Science was defined. Most of the activity was dedicated to the elaboration of standards to retrieve and visualize data in this field, and to provide light procedures to teams who wish to contribute with on-line data services. The architecture of this VO system and selected solutions are presented here, together with existing demonstrators

L'intérêt de la spectroscopie proche infrarouge en analyse de terre (synthèse bibliographique)

Use of near-infrared reflectance spectroscopy in soil analysis. A review. This paper presents a literature review on the development of near infrared reflectance spectroscopy for soil analysis and the contribution of this technique to the evaluation of soil fertility analysis. This technique is used to estimate the chemical composition of soil samples on the basis of their absorption properties. It is therefore an indirect method of measurement, which requires a calibration phase for the prediction of these properties. NIR spectroscopy offers many advantages compared to reference analysis: it is known to be a physical, non-destructive, rapid, reproducible and low cost method. Often employed in other analytical domains, such as agro-food, NIR spectroscopy has, however, seldom been used in soil characterization, due to the complexity of the soil matrix. Thanks to the development of chemometric methods, numerous studies have recently been conducted to evaluate the feasibility of the application of the technique in soil analysis. Most authors conclude that NIR spectroscopy is promising; however, to date, use of the technique has not spread to routine laboratories. The paper is organized as follows. Firstly, we provide an overview of the NIR spectroscopy technique and related chemometric methods. Secondly, we describe the soil characteristics that can be predicted using this technique. Finally, we detail examples of results that have been obtained through the use of the technique, mainly in the determination of clay and organic carbon content, and of cation exchange capacity

Observational Evidence for the Associated Formation of Blobs and Raining Inflows in the Solar Corona

The origin of the slow solar wind is still a topic of much debate. The continual emergence of small transient structures from helmet streamers is thought to constitute one of the main sources of the slow wind. Determining the height at which these transients are released is an important factor in determining the conditions under which the slow solar wind forms. To this end, we have carried out a multipoint analysis of small transient structures released from a north-south tilted helmet streamer into the slow solar wind over a broad range of position angles during Carrington Rotation 2137. Combining the remote-sensing observations taken by the Solar-TErrestrial RElations Observatory (STEREO) mission with coronagraphic observations from the SOlar and Heliospheric Observatory (SOHO) spacecraft, we show that the release of such small transient structures (often called blobs), which subsequently move away from the Sun, is associated with the concomitant formation of transient structures collapsing back toward the Sun; the latter have been referred to by previous authors as "raining inflows." This is the first direct association between outflowing blobs and raining inflows, which locates the formation of blobs above the helmet streamers and gives strong support that the blobs are released by magnetic reconnection.Peer reviewe

Répartition de la chevêche d'athéna (athene noctua scop.) et variation d'échelle d'analyse des paysages

Une typologie paysagère établie à partir de pixels élémentaires de 250 m de côté dans trois zones en France (Vosges du Nord, Scarpe-Escaut et Causse Méjean) a permis de déterminer 5 à 8 types primaires, permettant d'expliquer la répartition des Chevêches d'Athéna (Athene noctua). Les milieux favorables sont anthropisés, avec des modes d'occupation du sol conduits sur de petites surfaces. Une typologie secondaire réalisée pour différentes échelles d'analyse par agglomération de pixels élémentaires révèle une certaine diversité incluant des éléments paysagers favorables. Ainsi les fenêtres obtenues par agglomération de pixels élémentaires adjacents les plus favorables ne sont pas uniquement formées de pixels favorables aux chouettes. Cette typologie secondaire a permis de déterminer une échelle d'analyse de l'habitat expliquant la répartition de l'espèce et qui varie de 56 à 156 ha selon les zones d'étude.Distribution of the Little Owl (Athene noctua) is accounted for by reference to primary landscape types identified from a grid of 250 m x 250 m cells in three areas of France (Northem Vosges, Scarpe-Escaut Plain, and Causse Méjean) . Preferred environments are those affected by human activity where small areas are given over to different land uses. Secondary landscape types constructed for different scales by aggregating cells of primary landscape types of analysis reveal a very heterogeneous landscape mosaic. Windows formed by aggregating the most suitable adjacent cells are not exclusively composed of cells preferred by owls. These secondary landscape types provide a habitat scale of analysis explaining species distribution and ranging from 56 to 156 hectares depending on the study regions

Digital Signaling and Hysteresis Characterize Ras Activation in Lymphoid Cells

Activation of Ras proteins underlies functional decisions in diverse cell types. Two molecules, RasGRP and SOS, catalyze Ras activation in lymphocytes. Binding of active Ras to SOS' allosteric pocket markedly increases SOS' activity establishing a positive feedback loop for SOS-mediated Ras activation. Integrating in silico and in vitro studies, we demonstrate that digital signaling in lymphocytes (cells are “on” or “off”) is predicated upon feedback regulation of SOS. SOS' feedback loop leads to hysteresis in the dose-response curve, which can enable a capacity to sustain Ras activation as stimuli are withdrawn and exhibit “memory” of past encounters with antigen. Ras activation via RasGRP alone is analog (graded increase in amplitude with stimulus). We describe how complementary analog (RasGRP) and digital (SOS) pathways act on Ras to efficiently convert analog input to digital output. Numerous predictions regarding the impact of our findings on lymphocyte function and development are noted.National Institutes of Health (U.S.). Pioneer AwardNational Institutes of Health (U.S.) (1PO1/AI071195/01

BepiColombo’s Cruise Phase: Unique Opportunity for Synergistic Observations

The investigation of multi-spacecraft coordinated observations during the cruise phase of BepiColombo (ESA/JAXA) are reported, with a particular emphasis on the recently launched missions, Solar Orbiter (ESA/NASA) and Parker Solar Probe (NASA). Despite some payload constraints, many instruments onboard BepiColombo are operating during its cruise phase simultaneously covering a wide range of heliocentric distances (0.28 AU–0.5 AU). Hence, the various spacecraft configurations and the combined in-situ and remote sensing measurements from the different spacecraft, offer unique opportunities for BepiColombo to be part of these unprecedented multipoint synergistic observations and for potential scientific studies in the inner heliosphere, even before its orbit insertion around Mercury in December 2025. The main goal of this report is to present the coordinated observation opportunities during the cruise phase of BepiColombo (excluding the planetary flybys). We summarize the identified science topics, the operational instruments, the method we have used to identify the windows of opportunity and discuss the planning of joint observations in the future

First Solar Orbiter observation of the Alfvénic slow wind and identification of its solar source

Context: Turbulence dominated by large amplitude nonlinear Alfvén-like fluctuations mainly propagating away from the Sun is ubiquitous in high speed solar wind streams. Recent studies have shown that also slow wind streams may show strong Alfvénic signatures, especially in the inner heliosphere. Aims: The present study focuses on the characterisation of an Alfvénic slow solar wind interval observed by Solar Orbiter on July 14-18, 2020 at a heliocentric distance of 0.64 AU. Methods: Our analysis is based on plasma moments and magnetic field measurements from the Solar Wind Analyser (SWA) and Magnetometer (MAG) instruments, respectively. We compare the behaviour of different parameters to characterise the stream in terms of the Alfvénic content and magnetic properties. We perform also a spectral analysis to highlight spectral features and waves signature using power spectral density and magnetic helicity spectrograms, respectively. Moreover, we reconstruct the Solar Orbiter magnetic connectivity to the solar sources via both a ballistic and a Potential Field Source Surface (PFSS) model. Results: The Alfvénic slow wind stream described in this paper resembles in many respects a fast wind stream. Indeed, at large scales, the time series of the speed profile shows a compression region, a main portion of the stream and a rarefaction region, characterised by different features. Moreover, before the rarefaction region, we pinpoint several structures at different scales recalling the spaghetti-like flux-tube texture of the interplanetary magnetic field. Finally, we identify the connections between Solar Orbiter in situ measurements, tracing them down to coronal streamer and pseudostreamer configurations. Conclusions. The characterisation of the Alfvénic slow wind stream observed by Solar Orbiter and the identification of its solar source are extremely important aspects to understand possible future observations of the same solar wind regime, especially as solar activity is increasing toward a maximum, where a higher incidence of this solar wind regime is expected

Vortex nozzle interaction in solid rocket motors: A scaling law for upstream acoustic response

In solid rocket motors, vortex nozzle interactions can be a source of large-amplitude pressure pulsations. Using a two-dimensional frictionless flow model, a scaling law is deduced, which describes the magnitude of a pressure pulsation as being proportional to the product of the dynamic pressure of the upstream main flow and of vortex circu- lation. The scaling law was found to be valid for both an integrated noz- zle with surrounding cavity and a nozzle geometry without surrounding cavity that forms a right angle with the combustion chamber side wall. Deviations from the scaling law only occur when unrealistically strong circulations are considered

First-line therapy with gemcitabine and paclitaxel in locally, recurrent or metastatic breast cancer: A phase II study

BACKGROUND: This phase II study evaluated the efficacy and safety of gemcitabine (G) plus paclitaxel (T) as first-line therapy in recurrent or metastatic breast cancer. METHODS: Patients with locally, recurrent or metastatic breast cancer and no prior chemotherapy for metastatic disease received G 1200 mg/m(2 )on days 1 and 8, and T 175 mg/m(2 )on day 1 (before G) every 21 days for a maximum of 10 cycles. RESULTS: Forty patients, 39 metastatic breast cancer and 1 locally-advanced disease, were enrolled. Their median age was 61.5 years, and 85% had a World Health Organization performance status (PS) of 0 or 1. Poor prognostic factors at baseline included visceral involvement (87.5%) and ≥2 metastatic sites (70%). Also, 27 (67.5%) patients had prior adjuvant chemotherapy, 25 of which had prior anthracyclines. A total of 220 cycles (median 6; range, 1–10) were administered. Of the 40 enrolled patients, 2 had complete response and 12 partial response, for an overall response rate of 35.0% for intent-to-treat population. Among 35 patients evaluable for efficacy the response rate was 40%. Additional 14 patients had stable disease, and 7 had progressive disease. The median duration of response was 12 months; median time to progression, 7.2 months; median survival, 25.7 months. Common grade 3/4 toxicities were neutropenia in 17 (42.5%) patients each, grade 3 leukopenia in 19 (47.5%), and grade 3 alopecia in 30 (75.0%) patients; 1 (2.5%) patient had grade 4 thrombocytopenia. CONCLUSION: GT exhibited encouraging activity and tolerable toxicity as first-line therapy in metastatic breast cancer. Phase III trials for further evaluation are ongoing