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Light beams may carry both a spin and an orbital angular momentum (OAM). While the former is associated to their polarization state, the latter stems from the geometrical properties of their wavefront. In their prototypical form, beams with OAM have "donuts-like" intensity profile and helicoidal wavefront, carrying integral multiples of h as angular momenta. Since their "rediscovery" in the late 90's, beams with OAM of visible wavelengths have found innumerable applications in quantum optics, microscopy or information transfer. A major recent development was the generation of such beams with much smaller wavelengths — in the extreme ultraviolet (XUV) — using synchrotron sources, free electron lasers as well as high harmonic sources (HHG). In this latter case, it creates ultrashort XUV sources of beams with OAM, suited for time-resolved applications at femtosecond and attosecond time scales. Remarkably, we showed that even though HHG is a non-perturbative process, the OAM transfer from the driving beam to the harmonics was purely parametric; i.e., the q-th harmonic — which can be thought as the upconversion of q infrared photons — carries q times the OAM of the driver [3, 4]. However, this rule limits severely the flexibility in choosing the OAM of the XUV emission.

International audience; We study theoretically and experimentally high-order harmonic generation (HHG) using two noncollinear driving fields focused in gases. We show that these two fields form a nonstationary blazed active grating in the generation medium. The intensity and phase structure of this grating rule the far-field properties of the emission, such as the relative amplitude of the diffraction orders. Full macroscopic calculations and experiments support this wave-based picture of the process, complementing and extending its standard “photon” picture. This insight into the HHG process allows us to envision structuration schemes to convert femtosecond lasers to attosecond pulses with increased efficiency.

Optical vortices are currently one of the most intensively studied topics in optics. These light beams, which carry orbital angular momentum (OAM), have been successfully utilized in the visible and infrared in a wide variety of applications. Moving to shorter wavelengths may open up completely new research directions in the areas of optical physics and material characterization. Here, we report on the generation of extreme-ultraviolet optical vortices with femtosecond duration carrying a controllable amount of OAM. From a basic physics viewpoint, our results help to resolve key questions such as the conservation of angular momentum in highly nonlinear light–matter interactions, and the disentanglement and independent control of the intrinsic and extrinsic components of the photon's angular momentum at short-wavelengths. The methods developed here will allow testing some of the recently proposed concepts such as OAM-induced dichroism, magnetic switching in organic molecules and violation of dipolar selection rules in atoms., The controlled generation of extreme-ultraviolet beams with controllable topological charge has not been demonstrated. Here, Gauthier et al. report on the generation of extreme-ultraviolet optical vortices with femtosecond duration carrying a controllable amount of orbital angular momentum.

African forest bulbuls of the genus Bleda are usually placed into three separate species: B. syndactyla and B. eximia distributed both in Upper and Lower Guinea forest blocks, and B. canicapilla restricted to the Upper Guinean one. Acoustic data lead to question traditional morphologically-based species limits in this genus. Colouration patterns and measurements, particularly bill shape and length, wing and tail lengths, are reconsidered for all taxa. Multivariate (discriminant functions) analyses lead to separate nominate B. eximia as an Upper Guinean species distinct from Lower Guinean B. notata. Furthermore B. eximia appears closer to B. syndactyla than to the other two species. Acoustically, by the physical traits of their calls and songs as well as the behaviour associated with their production, B. eximia and B. syndactyla are very close and quite different from B. canicapilla and B. notata which constitute another pair of very close species. Obviously, in the frame of the biological species concept, the four taxa branched in two groups from a common ancestor, B. eximia and B. syndactyla represent a species-pair whereas B. notata and B. canicapilla are allospecies of a single superspecies. Allopatric speciation patterns based on alternate fragmentations and unitings of forests can be drawn from present knowledge of African forest history in relation to Pleistocene-Holocene events. However, a brief review of recent data on interspecific genetic differentiation in birds suggests an important discrepancy between biogeographical and molecular time calibrations. The development of molecular studies appears as a priority for the understanding of the evolution of African tropical forests birds.

International audience; In this paper, we propose a method to identify, on a mesh, geometric primitives commonly used in mechanical parts (plane, sphere, cylinder, torus, cone) in order to improve the quality of the surface remeshing. We have already presented techniques to adapt an existing surface mesh based on a mesh-free technique denoted as diffuse interpolation. In this approach, a secondary local geometrical model is built from the mesh. From this model, principal curvatures are calculated and the type of surface can be determined from the computation of the curvatures. Some of the concepts presented here are original while others have been adapted from techniques used in reverse engineering. Our approach is not limited to feature recognition on meshes but has been extended to a set of points.

Les travaux presentes se placent dans la continuite des recherches autour des techniques de remaillage a l'aide de l'approximation diffuse, effectuees a l'Universite de Technologie de Compiegne. Un...

The Petawatt Aquitaine Laser (PETAL) facility was designed and constructed by the French Commissariat à l'énergie atomique et aux énergies alternatives (CEA) as an additional PW beamline to the Laser MegaJoule (LMJ) facility. PETAL energy is limited to 1 kJ at the beginning due to the damage threshold of the final optics. In this paper, we present the commissioning of the PW PETAL beamline. The first kJ shots in the amplifier section with a large spectrum front end, the alignment of the synthetic aperture compression stage and the initial demonstration of the 1.15 PW @ 850 J operations in the compression stage are detailed. Issues encountered relating to damage to optics are also addressed.

UNLABELLED: We conducted a pilot study to assess the prevalence of hypovitaminosis D among Iranian women and their newborns. Blood samples were taken from 50 mothers (age 16-40 yr) and their neonates at term delivery in the largest Tehran hospital. The results showed that 80% of the women had 25-hydroxyvitamin D (25-OHD) concentrations of less than 25 nmol/l. Mean maternal plasma calcium and phosphatase alkaline concentrations were in the normal range. The mean maternal serum immunoreactive parathyroid hormone concentration of women with hypovitaminosis D (i.e., 25-OHD levels

International audience; We present the experimental demonstration of a subaperture compression scheme achieved in the PETAL (PETawatt Aquitaine Laser) facility. We evidence that by dividing the beam into small subapertures fitting the available grating size, the sub-beam can be individually compressed below 1 ps, synchronized below 50 fs and then coherently added thanks to a segmented mirror. " Split-aperture laser pulse compressor design tolerant to alignment and line-density differences

Plasma lipids and apolipoproteins, and hepatic LDL receptor and HMG-CoA reductase activities in biopsy samples were measured in high- and low-responding rhesus monkeys maintained on a cholesterol-rich and regular diets. The effect of a 30-day cholestyramine treatment on the above parameters under both dietary conditions was also determined. On the cholesterol-rich diet the high-responders, when compared to the low-responders, had several-fold increased plasma cholesterol and apoB concentrations and significantly lower HDL apoA-I and cholesterol concentrations. Hepatic LDL receptor and HMG-CoA reductase activities were not detectable in the high-responders, while the low-responders expressed a reduced number of LDL receptors of normal affinity. Administration of cholestyramine resulted in a rapid induction of the hepatic LDL receptors in the high-responders and a small additional increase in the low-responders. Cholestyramine treatment also stimulated the expression of the hepatic HMG-CoA reductase in both groups of monkeys. These changes were accompanied by a dramatic drop in plasma cholesterol and apoB concentrations in the high-responders and, to a lesser extent, in the low-responders. Plasma HDL concentrations in the high-responders rose to levels higher than those seen in the low-responders. The affinity and receptor number were similar in both groups of monkeys on the control diet, but the low-responders had significantly higher HMG-CoA reductase activities. Administration of cholestyramine during the control diet had a small but significant additional effect on the hepatic LDL receptors of the low-responders but not of the high-responders.(ABSTRACT TRUNCATED AT 250 WORDS)

Definition and lived-in reality of "autonomy" an "human-dignity" may differ as can be shown by means of a patient's situation: it varies whether patient, relatives, general practitioner or hospital doctor are involved. It is most important to assure these terms not only to be fiction but to become a lived reality.

We propose a method to adapt a three-dimensional surface mesh. The data needed to optimize the mesh have been reduced to an initial mesh. The building of the geometrical model is based on a local Hermite interpolation calculated from the nodes of the initial mesh and from the normal vectors to the surface calculated from the mesh. The determination of an interpolating local surface equation, however continuous over the domain, enables us to locate nodes on the surface with respect to the curvature during a refinement process. It also allows us to control the coarsening of the mesh. The local surface equation is used to compute the principal curvatures on the surface for two main purposes, error estimation and feature recognition..The remeshing procedures are used to refine or coarsen the mesh but also in a final step to enhance the shape quality of the elements.

We conducted a pilot study to assess the prevalence of hypovitaminosis D among Iranian women and their newborns. Blood samples were taken from 50 mothers (age 16-40 yr) and their neonates at term delivery in the largest Tehran hospital. The results showed that 80% of the women had 25-hydroxyvitamin D (25-OHD) concentrations of less than 25 nmol/l. Mean maternal plasma calcium and phosphatase alkaline concentrations were in the normal range. The mean maternal serum immunoreactive parathyroid hormone concentration of women with hypovitaminosis D (i.e., 25-OHD levels25 nmol/l) was above normal range and significantly different from that of women without hypovitaminosis D.The mean cord serum 25-OHD concentration was very low (4.94+/-9.4 nmol/l) and that of infants of mother with hypovitaminosis D were almost undetectable (1.2+/-1.2 nmol/l).

To compare serum C-reactive protein levels measured using a highly sensitive immunonephelometry method in patients with rapidly destructive versus slowly progressive hip osteoarthritis.Ten patients meeting criteria for rapidly destructive hip osteoarthritis were compared to 25 patients with slowly progressive hip osteoarthritis defined as less than 0.20 mm joint space loss over the last year. Serum C-reactive protein was assayed using an immunonephelometry method with a detection threshold of 0.17 mg/L and a coefficient of variation of less than 5%.One patient in each group was excluded because of a C-reactive protein level greater than 15 mg/L. The mean C-reactive protein level in the remaining 33 patients was 3.05 +/- 3.46 mg/L (range, 0.10-14.9 mg/L). Mean C-reactive protein was significantly higher in the rapidly destructive group than in the slowly progressive group (5.61 +/- 4.75 versus 1.94 +/- 1.98 mg/L, P = 0.01), even after adjustment for potential confounding factors.Our data suggest that rapidly destructive hip osteoarthritis may be associated with some degree of inflammation reflected by a small but significant increase in serum C-reactive protein levels.

A variety of effective methods to prevent falls of the elderly are presented for everyday practice.

The indications for a specific rehabilitation training programme for elderly stroke patients are discussed. Special symptomatology, such as hemi-anesthesia as a result of a damaged perceptual process, apraxia including apraxia of dressing, communication disorders and affective disorders are presented. The measures to be taken for effective rehabilitation in hospital, in an institution for the elderly or in the home care situation are indicated. In addition, the physician has to have marked ability for empathic comportment.

Protein-energy malnutrition is a frequent, but often overlooked problem in geriatric patients. To prevent malnutrition and its severe complications, a systematic strategy for identifying signs, symptoms and risk factors of malnutrition is required. In this review we present a plan for a multidimensional nutritional workup, including functional nutritional assessment. Special aspects of malnutrition management in geriatric patients are discussed (e.g. dementia, tube-feeding, environmental aspects). Use of available diagnostic and therapeutic measures for preventing malnutrition may lead to improved quality of life in many geriatric patients.

A multi-Petawatt high-energy laser PETAL coupled to the Ligne d'Int?gration Laser (LIL) is under construction in the Aquitaine Region in France. This Petawatt laser will be dedicated to academic experiments in the fields of high energy density physics and ultra high intensity. Nd?:?glass laser chain coupled with the chirped pulse amplification (CPA technique allows delivery of high energy. Optical parametric CPA for pre-amplification and a new compression scheme will be implemented. PETAL is designed to deliver 3.6?kJ of energy in 500?fs on a target corresponding to 7.2?PW. The PETAL beam linked to the up to 60?kJ?ns UV beams from the LIL will present new scientific research opportunities.

The urine of human coffee drinkers who ingested 12 g of instant coffee per day, during 4 days in a first experiment or 12 g within 2 h in a second experiment, was fractionated by XAD-2 column chromatography. The non-polar urine fractions so obtained were not mutagenic in the Ames Salmonella tester strains TA98 or TA100 in either experiment, either with or without β-glucuronidase treatment of the urine. The non-polar urine fraction of smokers, who smoked 20–30 cigarettes per day during 4 days in the first experiment or 7–18 cigarettes during 7 h in the second experiment, was mutagenic when metabolically activated.

The many advantages of broad-band systems are not fully exploitable without the availability of intense sources with high radiance and emitting on a broad spectral band. An electro-optic tuning of a commercial cw dye laser is proposed for simulating such sources. A conventional intra-cavity Pockels cell is used for simulating such sources. The main characteristics of laser emission are discussed (linewidth, polarization, tuning speed, etc.); the applications given as examples deal with metrology (surface testing) and optical transmission by spectral modulation of light.

Air Force communications has expanded from the most elementary requirements in World War I to an enormous military world-wide industry. It exceeds the requirements and capabilities of commercial systems without standardization, engineering, installation and maintenance capabilities required for the Job. A new system concept is proposed to reduce types of equipments, increase efficiency and reduce engineering, installation, operation, maintenance and supply problems.

Resume La pathologie des Pseudomonas a l'hopital est consideree sous deux aspects : l'apport direct d'un pouvoir pathogene et l'apport d'une resistance plasmidique aux antibiotiques et aux antiseptiques. L'importance nosocomiale des Pseudomonas non aeruginosa est illustree par la description d'une epidemie due a Pseudomonas picketti ayant provoque 28 chocs septiques. La source de l'infection s'est revelee etre pharmaceutique, des solutions de glucose etant infectees par l'eau de refroidissement de l'autoclave de la pharmacie. De nombreux bacilles Gram-negatifs ont ete colonises tout-a-coup par des plasmides de resistance aux desinfectants mercuriels apportes dans cet hopital par une souche de Pseudomonas aeruginosa P13.

Fur das im Jahre 1978 eroffnete Tagesspital — eine wesentliche Erganzung eines geriatrischen Zentrums — wurden priority Ziele formuliert (Tabelle 1). Soll das Tagesspital eine Patientenaufnahme-Kapazitat beibehalten, so ergibt sich als Ziel zwangslaufig eine limitierte Aufenthaltsdauer der Patienten. Soll der Aufenthalt begrenzt sein, werden Entlassungen aus dem Tagesspital notig.

To plan a dental care program for geriatric patients, the dental treatment needs of 219 elderly patients consecutively admitted to a geriatric hospital were quantitatively assessed. Of 89 patients with residual teeth, 97.8% were assessed as needing dental treatment of a mean projected duration of about 312 min per patient. Of the 130 edentulous patients, 30.8% needed dental treatment of a mean projected duration of about 194 min per patient. Patients exhibiting high (greater than 60 min) dental treatment needs were more frequently impaired in activities of daily living than patients with low (less than or equal to 60 min) dental treatment needs (e.g. impaired transfer function 60.2% vs. 28.0%). There was no difference in the oral hygiene or in the cleanliness of removable dentures between patients needing and not needing help in activities of daily living. In conclusion, the present results show a high amount of dental treatment needed in elderly patients. For the planning of an effective dental care program, special attention has to be paid to the interdisciplinary treatment of patients with limitations in activities of daily living. Furthermore, the improvement of the oral hygiene status is of paramount importance in most elderly patients.

A conventional intra-cavity Pockels cell was used to achieve tunable operation of a Rh 6G dye laser. Wavelength tuning over a broad spectral band (500 PO with driving voltages of some hundreds volts was achieved. This system is suitable for simulating broadband illumination in optical processors working with spatially coherent but temporally incoherent sources. Applications dealing with the measurement of optical path-differences through the channelled spectrum technique, surface testing by chromatic speckle phenomenon and optical transmission by spectral modulation of light are reported.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Recently it has been shown that there is a high prevalence of treatable dental conditions in elderly subjects in Switzerland. The purpose of the present prospective study was to assess the value of an oral screening examination intended to help the primary care physician to determine which patients should be referred to a dental service for specialized treatment. Of 219 patients aged over 65 referred consecutively to a geriatric hospital, 58.4% were objectively in need of dental treatment according to the data obtained by a dentist. In a multiple logistic analysis, 4 oral screening criteria (presence of residual teeth of the patient's own, no prosthetic replacement of an edentulous arch, subjective dental treatment requirement, subjective chewing impairment) were found to predict the objectively assessed dental need with a sensitivity of 93.0% and a specificity of 82.4%. Among the patients with objective dental treatment requirement not predicted by the screening examination, 3 had ulcerations of the oral mucosa. An intraoral soft-tissue examination should therefore be included in the screening examination. In conclusion, simple oral screening may serve to identify patients needing dental care with a high degree of diagnostic accuracy. This enables the primary care physicians to screen for oral and dental problems and to refer patients in the same way as for other special treatment problems.

An example of a way to establish contact between hospital and outpatient care was demonstrated by the method of working at a clinic for geriatrics and rehabilitation. The basis for evaluation of the working method concerning the patient is optimal information about his situation at the time of hospitalisation. An objective for the hospitalisation can be determined together with the patient. The progress achieved during hospitalisation is judged at regular intervals by the patient and the staff taking care of him. This makes an estimation of the length of required hospitalisation possible. About 40% of the patients returning to family practitioner care require outpatient care. The division between the different services involved is demonstrated. The working method was judged, based on an inquiry at the family practitioners.