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The establishment and interpretation of diameter and height structures is essential for forest management decision-making. This study aims to describe the diameter structure and spatial distribution of Pinus halpensis populations in the Beni Oudjana (Khenchela) forest. Knowledge of these parameters is an essential step in their sustainable management. The diameter at 1.30 m from the ground, the total height of P. halpensis individuals were measured on 6 plots according to an altitudinal gradient. The diameter and height structures were established according to the diameter or height classes and adjusted to the theoretical Weibull distribution. The density of the species increases according to this gradient from 4060 feet/hectare in plot P3 (at an altitude of 1472m) to 340 feet/hectare in plot P2 (1106m altitude). The stand of plot 4 is characterized by the lowest average values for diameter (5.784±7.03cm) height (3.19±2.56m), basal area (0.00±0.02m2/ha), total volume (0.03±0.10m3/ha) and relative density of 15%. Analysis of diameter and height structures shows an increase in the frequency of young individuals. These results contribute to the improvement of knowledge on current status indicators of natural P. halpensis stands that can be used as a basis for the management of the Beni Oudjana forest. [ABSTRACT FROM AUTHOR]

Résumé Les entraîneurs au tir à la carabine en salle savent qu’ils sont incapables de fournir aux tireurs des critères précis qui leur permettent de déterminer rigoureusement l’instant où il faut appuyer sur la queue de détente. Ils savent seulement qu’il faut anticiper l’instant du croisement du centre de la cible par la ligne de mire. La possibilité, nouvelle, de suivre simultanément, au moment du tir, les mouvements du centre de gravité du tireur et de sa ligne de mire explique cette incapacité en montrant l’indépendance des mouvements de l’arme et du corps. Une nouvelle piste de travail est ainsi ouverte à ces tireurs : au moment du tir, il faut éviter que l’arme se déplace par rapport au corps, et veiller au contraire qu’elle se déplace avec le corps. Summary The indoor rifle shooting coaches know they are unable to provide specific criteria to the shooters that allow them to determine precisely the moment they need to press the trigger. They only know that they must anticipate the moment when the crosshairs crosses the center of the target. The possibility, new, of monitoring simultaneously at the time of shooting, the movements of the center of gravity of the shooter and his line of sight explains this failure by showing the independence of the movements of the rifle and of the body. So, a new line of work is open to these shooters: when firing they have to avoid that the weapon moves relative to the body, and on the contrary, they have to ensure that the weapon moves with the body. [ABSTRACT FROM AUTHOR]

Abstract: In order to help the analysis of adverse effects of transfusion, factsheets have been written by working groups of the French agency for the safety of health products ANSM. Each factsheet deals with a blood transfusion side effect and is composed of five parts, including pathophysiological mechanisms, diagnostic criteria, management recommendations, etiologic investigations and rules for filing the notification form to ANSM. Since 2006, 11 factsheets have been published on the French haemovigilance network website. The major characteristics of the two last sheets published “post-transfusion purpura” and “non erythrocyte incompatibility reaction” are presented, followed by the updated card for “allergy”. These factsheets give relevant guidelines allowing better evaluation of recipients’ adverse reactions, particularly their diagnosis, severity and accountability. They also could initiate studies among European and international haemovigilance networks. [Copyright &y& Elsevier]

Abstract: Since 1994, adverse effects of transfusion transmitted to the French haemovigilance network are registered on “e-fit”, the database of the French agency for the safety of health products (Afssaps). In order to improve their analysis, guidance supports have been made by Afssaps working groups. Each support deals with a blood transfusion side effect and is composed of five parts including pathophysiological mechanisms, diagnostic criteria, management recommendations, etiologic investigations and rules of filing the notification form on e-fit. The major characteristics of sheets published or soon-to-be published are presented: transfusion-related acute lung injury, transfusion-transmitted bacterial infection, non-haemolytic febrile reaction, allergic reaction, transfusion-associated circulatory overload, hypotensive transfusion reaction, alloimmunization, erythrocyte incompatibility reaction and hemosiderosis. These new supports give relevant guidelines allowing a better analysis and evaluation of recipients’ adverse reactions, particularly their diagnosis, gravity and accountability. They could also initiate studies in European and international haemovigilance and transfusion networks. [ABSTRACT FROM AUTHOR]

Abstract: Priabonian age is highlighted for the first time in Corsica in the Venaco Formation using the presence of specific microfauna (in particular some representatives of Turborotalia cerroazulensis lineage). This silicoclastic formation is mainly represented by coarse facies. It is composed of three members from south to north and from oldest towards youngest: member of Uboli, Cardo and Orsu. The sedimentologic analysis reveals a gravity depositional environment, involving different type of currents. Sedimentologic and chronologic characteristics make the Venaco Formation and the Annot Formation (p.p.) equivalent. Dating the Venaco Fm. brings confirmation that the green schist metamorphism of the Variscan batholith and the related deformation are from the pre-Priabonian period. [Copyright &y& Elsevier]

Effect of reduced gravity on heat transfer and rewetting temperature during quenching: application to rocket engines reignition. This paper describes the experimental strategy developed to improve the modeling of liquid-vapor flows during the chill down of rocket engines by cryogenic fluid in microgravity. A similarity analysis is performed to determine the relevant dimensionless numbers for the design of an experiment similar to engine flows. A literature review on reduced gravity quenching experiments, and on rewetting temperature and film boiling heat transfer shows the lack of validated models for microgravity. Experimental results obtained with the quenching of a glass tube by FC72 during parabolic flight are presented. Especially the impact of gravity and subcooling on rewetting temperature and film boiling heat transfer is investigated. Results show an increase in rewetting temperature, and a decrease in film boiling heat transfer under reduced gravity in agreement with the literature. The comparison of 0g flow pattern with corresponding tests on ground point out a behavior at fig closer to 1g upflow than 1g downflow. [ABSTRACT FROM AUTHOR]

Summary: The authors present their experience of surgery in weightlessness conditions. Russians and Americans already focused on that subject but two questions were still unsolved: what was the limit of human skill in these extreme conditions and was it possible to operate a human under total safety? Between 2003 and 2007, using a 0G plane for our experiment, we focused on two goals: firstly, the conception of a microsurgical module to test complex microsurgical procedures in rats and secondly, the construction of a surgical workstation with specific air filtration device and define surgical and anaesthetic protocols to carry on a surgery in man. In September 2003, we succeeded to perform the microscopic report of a 0,5mm artery (which is the smallest we can suture in terrestrial conditions) by using seven stitches of 10×0 monofilament suture. The 27th of September 2007, we removed a lipoma from the forearm of a 47-year-old man. These experiments take place in a wide program of development of telesurgery controlled through satellite transmission with all forthcoming civil, military and humanitarian applications. [Copyright &y& Elsevier]

Abstract: The measures of the fields of density, pressure and temperature of an atmospheric column are often scarce and sometimes inaccurate, which needs a necessary reconstruction. An original technique of reconstruction with a confined storage reduced to 6 parameters only, is proposed and validated by using a mathematical model with an altitude dependent gravity, and a discretization by an original well-balanced scheme. To cite this article: A.-Y. LeRoux, L. Vignon, C. R. Acad. Sci. Paris, Ser. I 346 (2008). [Copyright &y& Elsevier]

The solidification of binary alloys is problematic insofar as much heterogeneity likely to weaken the product appears. These heterogeneities can be at the same time of composition (called segregations) and of structures. The segregations present, moreover, the disadvantage of as well appearing on a mesoscopic scale (freckles) as on an ingot scale (macrosegregation). It appears that gravity plays a prevalent part in the formation and the evolution of heterogeneities. Moreover the titanium-aluminium alloys present peritectic solidification: during peritectic solidification two solid phases are present in the ingot. A numerical modelling of solidification based on the statistical average was established which takes into account the specificity of these alloys. The calculations carried out in condition of microgravity and forced convection show that the convection in the vicinity of the front of solidification influences the localization of heterogeneities. [ABSTRACT FROM AUTHOR]

Abstract: The present work is based on various filtered maps (horizontal derivative, upward continuation) and Euler deconvolution of the gravity data from northeastern Morocco. These results allow the delineation of many geological structures, such as faults, basins, or diapirs. Some of these structures are hidden totally or partially by the Mesozoic and Cenozoic cover. The results were used to make a structural map of the study area; this map confirms the existence of several faults, localised or inferred, from former geological studies. It complements information on some of them and outlines a great number of deep or near-surface faults that had remained unknown until the present time. The major features show two principal directions: N080°–085° and N055°–065°, with a predominance of the latter, and their depth can reach 4500m. The N080°–085° directions correspond to the Kebdana, Sidi Bouhouria, Naima, and Guefait faults, and the N055°–065° directions correspond to a fault parallel to the Mediterranean coast and the Moulouya, Madagh, Angad, and Zekkara faults. [Copyright &y& Elsevier]

Abstract: Following current evidence, it is widely accepted that many asteroids would be ‘gravitational aggregates’, i.e. bodies lacking internal cohesion. They could mainly originate from the catastrophic disruption of some parent body, through the gravitational re-accumulation of the resulting fragments. The same events produced the dynamical families that we observe. In this work we address the problem of the origin of shapes of gravitational aggregates, that could contain signatures of their origin. We use a N-body code to simulate the collapse of a cloud of fragments, with a variety of initial velocity distributions and total angular momentum. The fragments are treated as inelastic spheres, that rapidly accumulate to form rotating aggregates. The resulting shapes and rotational properties are compared with theoretical predictions. The results show that only a precise category of shapes (flattened spheroids) are created via this mechanism. This may provide interesting constraints on the evolution of asteroid shapes, in particular for those with one or more satellites. To cite this article: J.-F. Consigli et al., C. R. Physique 8 (2007). [Copyright &y& Elsevier]

Abstract: Troughs in Tunisia are interpreted as Plio-Quaternary structures associated to normal faults (grabens) or to flexure faults. Gravity data and seismic sections are used in this study to clarify the structure and the geodynamic evolution of an example of trough: the Grombalia trough (northeastern Tunisia), since the Upper Miocene to the Quaternary. A high residual negative gravity anomaly, which reaches −15 mGal, is interpreted as being related to the thickening of Mio-Plio-Quaternary deposits (and probably older), as illustrated by seismic data. This subsidence has been the result of a negative flower structure related to strike-slip faults that have been reactivated with normal component during the Upper Miocene and with reverse component during the Pliocene. Seismic and gravity data demonstrate that the fault system is rooted, and more than four kilometres deep. The Grombalia example outlines the association between troughs and strike-slip faults; such a system is recognized in Tunisia, in the Ionian Sea and in the Pelagian Sea. To cite this article: M. Hadj Sassi et al., C. R. Geoscience 338 (2006). [Copyright &y& Elsevier]

Abstract: This study is based on the analysis and the interpretation of the gravity data of the Tadla basin. Its purpose is to increase the knowledge of this basin structure. A residual anomaly map was first calculated from the Bouguer anomaly data witch are strongly affected by a regional gradient. The computed map provides information on the ground density variation but it does not bring enough of new elements. Data filtering allows us to emphasize the structures affecting the basin. We chose the horizontal gradient coupled to the upward continuation techniques that permit to highlight news structures and to give information on their dip. The elaborated structural map of the study area constitutes a useful document for rationalizing the future groundwater exploration in the Tadla basin. To cite this article: A. Najine et al., C. R. Geoscience 338 (2006). [Copyright &y& Elsevier]

Abstract: The multiscale wavelet analysis has been applied to the gravity data from northeastern Morocco to map the major geological contacts, such us faults. Hence, the faults affecting the survey area were outlined with their importance level and dip direction. Seismic data confirm these results and testify the efficiency of this method, particularly in studying structure of plains. The structural map established is a very useful document in the planning of natural resources investigations (i.e. water, mines) to be undertaken in the area of study. To cite this article: D. Khattach et al., C. R. Geoscience 338 (2006). [Copyright &y& Elsevier]

Abstract: Man, who is composed of articulated segments, is constantly subjected to gravity in static equilibrium (posture) as in motion. The classical approach of biomechanics consists in describing intersegmentary tridimensional kinematics and the mechanical actions involved in motion. This article puts forward a more cross-disciplinary approach by describing as well: the interactions between mechanics and biochemistry, that is, the link existing between the constraints resulting from motion in the level of osteoligamentary structures and tissue metabolism; the interactions existing between mechanics and neurology, that is, the link between those same constraints in the level of mecanoreceptors and the neurological control of this motion. [Copyright &y& Elsevier]

Abstract: Cell ageing is responsible for the increasingly creased appearance of our skin. The ageing of the structures of the face is attributed primarily to the effect of gravity on the tissues. The theory expounded below sets out to prove that the main and initial cause of this ageing is the repeated contractions of the mimic muscles. This concept attributes only a secondary role to gravity in the ageing process, which is initially brought about by muscular contractions. An MRI study recently made it possible to demonstrate the anterior convexity curve of the mimic muscles in the young subject. This curve is due to the existence at the back of these muscles of a deep fat pad. In the young subject, the extent of its convexity and its location give a specific, youthful character to the movements, in terms of direction and amplitude, of the facial muscles. With age, the muscle gradually straightens and shortens due to the repeated contractions that expel the underlying fat and increase the tonus at rest. The application of these new findings to the ageing of the face gives rise to new technical possibilities both in the field of medicine and aesthetic surgery. These new techniques have the same targets: segments of the mimic muscles (maintain over time a good muscular curve and a low tonus at rest) and the underlying fatty convexities. As far as medicine is concerned, the combination of botulinum toxin and filling has proved its worth. But two technical elements are new: the filling products must, at several points, be injected primarily behind the muscle to treat the depressions naturally and restore the initial curve of the overlying muscle. A very low number of units (a quarter to one unit) of botulinum toxin must be injected into certain muscles to diminish the tonus at rest of these muscles without diminishing their strength in maximum contraction. In surgery, new possibilities to treat premature ageing include procedures that combine segmentary muscular weakening, micro liposuctions and retromuscular reinjections. The advantage with regard to the medical procedures is greater stability over time and the greater precision of these muscular actions (one third of a muscle can be weakened for example) and the fat reinjections can be more stable. These procedures can be performed under local anesthesia. In cases of more advanced ageing, surgery offers new treatment possibilities that include, for the midface region, the concentric malar lift. It replaces, on the orbital rim, the sub-orbicularis oculi fat that has descended eccentrically as a result of the contractions of the orbicularis oculi muscle. The procedure, using the subperiosteal detachment plane, is therefore stable over time. At the same time, specific muscles are weakened. The aims of restoring fatty volumes and muscular tonuses are thus achieved. Similarly, in the neck, the platysma muscle is specifically weakened. Each area is studied in line with its specificities. For the first time, the skin tension of the facelift has no more to be maximum to treat the relief of the jawl line, of the palpebro malar groove and so on. The skin tension becomes moderate, just to remove the excess of skin. The relief is faded with the specific muscular and fatty action. The name of this new concept is Face Recurve®. [Copyright &y& Elsevier]

Abstract: Objective. – The aim of this study was to compare the immediate effects of standard physiotherapy (S) and balneotherapy (B) on the postural capacity of subjects with lower-limb injuries. Methods. – The postural sway of 12 voluntary subjects was evaluated before (REF1 and REF2) and after two different physiotherapy sessions performed in the swimming pool (B) or under (S). The centre of pressure (CP) trajectory was recorded by use of a force platform. CP displacements in the mediolateral and anteroposterior axes were then separated into two elementary superimposed components: the horizontal motion of the centre of gravity (CG) and the difference between the CP and the vertical projection of the CG (CP-CG). The amplitude of the latter component (CP-CG) is thought to express neuromuscular activity. All trajectories were then analysed in terms of classical and frequency parameters. Results. – Postural sway did not differ before and after the physiotherapy sessions. Following both sessions, the mean CG velocity decreased significantly (P <0.5). The area of CP-CG trajectory was diminished solely by the aquatic exercise (P <0.5) and was associated with decreased amplitude of motion along the anteroposterior axis (P <0.05), which suggests decreased neuromuscular activity to maintain posture. Conclusion. – Interestingly, decreased motion was observed along the anteroposterior axis, which corresponds to ankle movements. Exercising lower-limb muscles under water could reinforce proprioceptive input, resulting in a better postural control. [Copyright &y& Elsevier]

Abstract: The monotony of the surface and of the deep structure of the Sahel domain in eastern Tunisia (low topographic area covered by a Quaternary series) induces the possible existence of an important subsiding collapsed block and associated faulted zones. Gravity data analyses have permitted the reconnaissance of the crustal and gravimetric setting of the northern part of the Sahel domain and the discussion of main outlines of subsurface structures. The deep structure of a particular zone (Kairouan–Sousse–Monastir area) demonstrates the existence of an east-west en-doigt-de-gant crustal thinning confirmed by the gravity data. This deep structuring is perfectly showed by the high-resolution second-order enhanced analytic signal technique developed to image geologic boundaries such as contacts and faults. This technique, correlated with the distribution of all seismic events in the last century, has permitted to define an important east–west Kairouan–Sousse–Monastir tectonic corridor (CKSM). This corridor corresponds to major faults oriented east-west, were some folded structures can be developed. To cite this article: H. Gabtni, C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

To study the effects of microgravity on the mechanisms involved in the regulation of body hydrous status, total body water (TBW), plasma volume (PV), and its main regulating hormones (plasma renin, aldosterone, atrial natriuretic peptide (ANP), anti-diuretic hormone (ADH)) were determined, by isotopic dilution, Dill and Costill’s formula, and radio-immunologic dosages, in 9 male subjects submitted to a 90-d head-down bed rest (HDBR). ADH was determined in 24 h urinary collection as well as osmolality, sodium, and potassium. Body mass decreased (–2.8 0.8 kg) as well as TBW (–7.2% 0.9%, i.e., –2.6 0.7 kg) and PV (–4.7% 1.8%). Renin and aldosterone were enhanced (+109.0% 15.4% and +87.2% 38.9%, respectively). Simultaneously, we observed a decrease in ANP (–33.2% 20.4%). Other variables, including ADH, were not affected by HDBR. Body mass and TBW decrease (and consequently lean body mass) are associated with muscle atrophy. Renin, aldostrerone, and ANP modifications are well explained by the decrease in PV, which was not enough to induce ADH changes. It suggests that in man, the main regulatory factor for ADH secretion is osmolality, when PV is modestly and progressively decreased without arterial pressure modification, which was the case in the present protocol. [ABSTRACT FROM AUTHOR]

Abstract: The surface of a paramagnetic liquid in the gravity field is not planar and horizontal in the presence of a magnetic field. This property is applied to the measurement of the static magnetic susceptibility. To cite this article: M. Dellagi, C. R. Physique 6 (2005). [Copyright &y& Elsevier]

The solid/liquid transition during crystal growth by a floating zone technique is analysed under microgravity conditions. The control of this technique by considering heating conditions and pulling velocity is studied. The difficulty attached to the phase change transition is surmounted by the use of an enthalpy–porosity formulation. The spatial distribution of the applied heating at the free surface strongly affects the dynamics of the system, the shape and position of the interface. The increase in the energy density reduces the response time of the fluid phase appearance in the transient regime. The flow near the singularity line depends more on the total energy than on the flux distribution. To cite this article: R. Bennacer et al., C. R. Mecanique 332 (2004). [Copyright &y& Elsevier]

Upright undisturbed stance constitutes a fundamental attitude involving very cunning sensori-motor strategies. Until now, few analyses on postural control have been undertaken to explain the influence of both supports in this particular task. With the aim of analysing asymmetrical postures resulting from neurological (hemiplegia) or traumatic (amputation) origins, a new analysis and a reference framework are proposed, describing the influence of each support in upright stance maintenance. Ten healthy adults (eight men and two women ranging in age from 20 to 42 years) volunteered for this study. The subjects were required to remain as still as possible in upright stance. The control mechanisms for equilibrium maintenance were estimated by separate measures of the elementary and resultant centres of pressure through two force platforms. The analysis of the relationship between the elementary and resultant centres of pressure on the one hand and the centre of gravity on the other hand emphasises that both took place similarly and at the same time in the control of upright undisturbed stance. This control is done through two strategies that come into play at the level of the ankle and/or hip in the medio-lateral and antero-posterior directions, respectively. Furthermore, the various trajectories (elementary and resultant centres of pressure, centre of gravity) and analytical methods (frequential, correlations and cross-correlations) are compared. This methodology should be very interesting in the analysis of pathologies inferring postural asymmetry in weight distribution, since one could suppose that asymetric patients could be characterised by specific control of both supports. [Copyright &y& Elsevier]

The Kuhmo greenstone belt (Eastern Finland) is mainly formed by mafic volcanic rocks and metasediments. Although the geological observations indicate that this belt appears as a supracrustal synform overlying a gneissic basement, its deep structures are actually unknown. The present gravity study intends to provide a better understanding of these structures. Interpretation of gravity anomalies of the Kuhmo belt, using two-dimensional modelling suggests that the structures of the belt are controlled by granitoids diapirs. Most of the calculated models show that the belt displays in section pocket-like shapes (purses) terminated by a gully-shape close to the surface. This particular geometry corroborates the hypothesis of a gravitational formation with the heavy volcanic material sinking in a light sialic crust. To cite this article: M. Jaffal et al., C. R. Geoscience 335 (2003). [Copyright &y& Elsevier]

We performed a gravity survey in the Mont-Blanc and Aiguilles Rouges ranges in order to improve the gravity data coverage of the Alpine crystalline external ranges, and to constrain the deep geometry of a crustal scale thrust. Preliminary results allow us to propose a geometry for the deep structure of the ranges, taking into account a major reverse fault that bounds the Mont-Blanc range: the Mont-Blanc shear zone. To cite this article: F. Masson et al., C. R. Geoscience 334 (2002) 1011–1019. [Copyright &y& Elsevier]

For regional and national study purposes, there is a high need for updating the terrain corrections (TC) in the French gravity database. We have recomputed the TC for all the French gravity stations from 50 m out to a distance of 167 km. We compute the TC with a flat-top-prism algorithm and three DEM with grid spacing of 50, 250 and 1000 m, used in the zones 53 m/3 km, 3 km/10 km et 10 km/167 km, respectively. Analysing the DEM/station Δz and comparing our results to the ones previously obtained in the Alps area, we estimate the accuracy of our TC to be better than 1 mGal. To cite this article: G. Martelet et al., C. R. Geoscience 334 (2002) 449–454. [Copyright &y& Elsevier]

OBJECTIVE: To evaluate, in normal and healthy adults, the postural effects induced by a protocol of body sway mirror feedback.MATERIALS AND METHODS: Two experimental conditions, one consisting in staring eyes open (EO) and one consisting in mirror feedback (MFB), are randomly proposed. Displacements of the centre of pressure (CP), issued from a force platform, are advantageously decomposed along medio-lateral ML and antero-posterior AP directions into two elementary components: the horizontal motions of the centre of gravity (CGh) and the difference CP-CGv. The former is recognised as the main controlled variable in upright stance whilst several clues can be assessed by the latter: the overall muscular activity, the ankle stiffness and the horizontal accelerations communicated to the CG. Elementary motions CGh and CP-CGv are then processed in the frequential domain and characterized through RMS and MPF parameters.RESULTS: For CP-CGv motions the MFB protocol induces larger MPF along the AP direction and thus an increased ankle stiffness. In addition, the RMS are slightly decreased, indicating that less motor units are called into play. On the other hand, no real effect is observed in the ML direction. A general trend is that the CGh amplitudes are diminished by the MFB protocol, especially in the ML direction where a statistical effect is noticed.CONCLUSION: The specificity of the effects induced by the MFB technique makes it an appropriate tool for re-establishing, especially on the AP direction, the balance functions, in particular those involving exaggerated CP-CGv motions. [Copyright &y& Elsevier]

Plants of Cassia fasciculata Michx, were grown under control led conditions with a diurnal rhythm of 14 h light and 10 h dark. The nyctinastic movements performed by the leaves were observed by time lapse photography, on plants inverted in the field of gravity and compared to those recorded on plants remaining in natural position. The movements were observed on leaves from which the petiolar gland has been, removed as well as on leaves in which it has been preserved. In plants inverted in the field of gravity, the leaflet movements were not disturbed but the petiolar ones were opposite to those observed on plants in natural position and smaller in amplitude (52 and 15 degrees difference between maximum and minimum positions respectively). This was not influenced by the removal of the petiolar gland. Inverting plants greatly shortened duration of closing and time spent maximally closed while increasing both duration of opening and time spent maximally opened. Removal of the petiolar gland did not influence the opening-closing schedule of the plants in normal position but in inverted plants it caused marked changes in this schedule. These results are discussed in connection with what is known about IAA. K+ and amyloplasts and their role in causing changes in pulvinus turgor. [ABSTRACT FROM AUTHOR]