Showing papers by "University of Nice Sophia Antipolis published in 2005"
TL;DR: The hypothesis was that arthroscopic repair of full-thickness supraspinatus tears achieves a rate of complete tendon healing equivalent to those reported in the literature with open or mini-open techniques.
Abstract: Background: Good functional results have been reported for arthroscopic repair of rotator cuff tears, but the rate of tendon-to-bone healing is still unknown. Our hypothesis was that arthroscopic repair of full-thickness supraspinatus tears achieves a rate of complete tendon healing equivalent to those reported in the literature with open or mini-open techniques.
Methods: Sixty-five consecutive shoulders with a chronic full-thickness supraspinatus tear were repaired arthroscopically in sixty-five patients with use of a tension-band suture technique. Patients ranged in age from twenty-nine to seventy-nine years. The average duration of follow-up was twenty-nine months. Fifty-one patients (fifty-one shoulders) had a computed tomographic arthrogram, and fourteen had a magnetic resonance imaging scan, performed between six months and three years after surgery. All patients were assessed with regard to function and the strength of the shoulder elevation.
Results: The rotator cuff was completely healed and watertight in forty-six (71%) of the sixty-five patients and was partially healed in three. Although the supraspinatus tendon did not heal to the tuberosity in sixteen shoulders, the size of the persistent defect was smaller than the initial tear in fifteen. Sixty-two of the sixty-five patients were satisfied with the result. The Constant score improved from an average (and standard deviation) of 51.6 ± 10.6 points preoperatively to 83.8 ± 10.3 points at the time of the last follow-up evaluation (p < 0.001), and the average University of California at Los Angeles score improved from 11.5 ± 1.1 to 32.3 ± 1.3 (p < 0.001). The average strength of the shoulder elevation was significantly better (p = 0.001) when the tendon had healed (7.3 ± 2.9 kg) than when it had not (4.7 ± 1.9 kg). Factors that were negatively associated with tendon healing were increasing age and associated delamination of the subscapularis or infraspinatus tendon. Only ten (43%) of twenty-three patients over the age of sixty-five years had completely healed tendons (p < 0.001).
Conclusions: Arthroscopic repair of an isolated supraspinatus detachment commonly leads to complete tendon healing. The absence of healing of the repaired rotator cuff is associated with inferior strength. Patients over the age of sixty-five years (p = 0.001) and patients with associated delamination of the subscapularis and/or the infraspinatus (p = 0.02) have significantly lower rates of healing.
Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.
1,191 citations
TL;DR: The Grammont reverse prosthesis offers a true surgical option in several situations where only limited possibilities were previously available: cuff tear arthrosis, persistent shoulder pseudo-paralysis due to a massive and irreparable cuff tear, severe fracture sequelae, prosthetic revision in a cuff-deficient shoulder, and tumor surgery.
1,009 citations
TL;DR: A stochastic model is introduced that accurately models the message delay in mobile ad hoc networks where nodes relay messages and the networks are sparsely populated and accurately predicts the messagedelay for both relay strategies for a number of mobility models.
615 citations
TL;DR: It is demonstrated that the larval fat body, equivalent to the vertebrate liver, is a key relay element for ecdysone-dependent growth inhibition and forms a humoral regulatory loop that determines organismal size.
Abstract: All animals coordinate growth and maturation to reach their final size and shape. In insects, insulin family molecules control growth and metabolism, whereas pulses of the steroid 20-hydroxyecdysone (20E) initiate major developmental transitions. We show that 20E signaling also negatively controls animal growth rates by impeding general insulin signaling involving localization of the transcription factor dFOXO and transcription of the translation inhibitor 4E-BP. We also demonstrate that the larval fat body, equivalent to the vertebrate liver, is a key relay element for ecdysone-dependent growth inhibition. Hence, ecdysone counteracts the growth-promoting action of insulins, thus forming a humoral regulatory loop that determines organismal size.
578 citations
TL;DR: This study combines data on human grouping patterns in a comprehensive and systematic study and identifies a discrete hierarchy of group sizes with a preferred scaling ratio close to three, which could reflect a hierarchical processing of social nearness by human brains.
Abstract: The ‘social brain hypothesis’ for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3–5, 9–15, 30–45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.
523 citations
TL;DR: It appears now that a fine tuning of the MAPKs regulates both normal and pathological adipogenesis, and the precise understanding of the cascade of these molecular events and the way to regulate them will be certainly crucial in order to efficiently fight obesity.
499 citations
TL;DR: It is argued that personal control over behavior, in the job and within the national culture, provides compensatory resources that reduce job strain and practical suggestions for minimizing job strain are proposed.
Abstract: Suppressing and faking emotional expressions depletes personal resources and predicts job strain for customer-contact employees. The authors argue that personal control over behavior, in the job and within the national culture, provides compensatory resources that reduce this strain. With a survey study of 196 employees from the United States and France, the authors supported that high job autonomy buffered the relationship of emotion regulation with emotional exhaustion and, to a lesser extent, job dissatisfaction. The relationship of emotion regulation with job dissatisfaction also depended on the emotional culture; the relationship was weaker for French customer-contact employees who were proposed to have more personal control over expressions than U.S. employees. Theoretical and research implications for the emotion regulation literature and practical suggestions for minimizing job strain are proposed.
458 citations
TL;DR: A demonstration of qubit transfer between photons of wavelength 1,310 nm and 710nm is reported, a nonlinear up-conversion process, with a success probability of greater than 5 per cent.
Abstract: Quantum communication is the art of transferring quantum states, or quantum bits of information (qubits), from one place to another. On the fundamental side, this allows one to distribute entanglement and demonstrate quantum nonlocality over significant distances. On the more applied side, quantum cryptography offers, for the first time in human history, a provably secure way to establish a confidential key between distant partners. Photons represent the natural flying qubit carriers for quantum communication, and the presence of telecom optical fibres makes the wavelengths of 1310 and 1550 nm particulary suitable for distribution over long distances. However, to store and process quantum information, qubits could be encoded into alkaline atoms that absorb and emit at around 800 nm wavelength. Hence, future quantum information networks made of telecom channels and alkaline memories will demand interfaces able to achieve qubit transfers between these useful wavelengths while preserving quantum coherence and entanglement. Here we report on a qubit transfer between photons at 1310 and 710 nm via a nonlinear up-conversion process with a success probability greater than 5%. In the event of a successful qubit transfer, we observe strong two-photon interference between the 710 nm photon and a third photon at 1550 nm, initially entangled with the 1310 nm photon, although they never directly interacted. The corresponding fidelity is higher than 98%.
404 citations
TL;DR: An algorithm to split an image into a sum u + v of a bounded variation component and a component containing the textures and the noise is constructed, inspired from a recent work of Y. Meyer.
Abstract: We construct an algorithm to split an image into a sum u + v of a bounded variation component and a component containing the textures and the noise. This decomposition is inspired from a recent work of Y. Meyer. We find this decomposition by minimizing a convex functional which depends on the two variables u and v, alternately in each variable. Each minimization is based on a projection algorithm to minimize the total variation. We carry out the mathematical study of our method. We present some numerical results. In particular, we show how the u component can be used in nontextured SAR image restoration.
369 citations
TL;DR: A collection of 75 strains of Pectobacterium chrysanthemi and the type strains of Brenneria paradisiaca (CFBP 4178T) were studied by DNA-DNA hybridization, numerical taxonomy of 121 phenotypic characteristics, serology and 16S rRNA gene-based phylogenetic analyses as discussed by the authors.
Abstract: A collection of 75 strains of Pectobacterium chrysanthemi (including all biovars and pathovars) and the type strains of Brenneria paradisiaca (CFBP 4178T) and Pectobacterium cypripedii (CFBP 3613T) were studied by DNA–DNA hybridization, numerical taxonomy of 121 phenotypic characteristics, serology and 16S rRNA gene-based phylogenetic analyses. From analysis of 16S rRNA gene sequences, it was deduced that P. chrysanthemi strains and B. paradisiaca CFBP 4178T formed a clade distinct from the genera Pectobacterium and Brenneria; therefore, it is proposed to transfer all the strains to a novel genus, Dickeya gen. nov. By DNA–DNA hybridization, the strains of P. chrysanthemi were distributed among six genomic species: genomospecies 1 harbouring 16 strains of biovar 3 and four strains of biovar 8, genomospecies 2 harbouring 16 strains of biovar 3, genomospecies 3 harbouring two strains of biovar 6 and five strains of biovar 5, genomospecies 4 harbouring five strains of biovar 2, genomospecies 5 harbouring six strains of biovar 1, four strains of biovar 7 and five strains of biovar 9 and genomospecies 6 harbouring five strains of biovar 4 and B. paradisiaca CFBP 4178T. Two strains of biovar 3 remained unclustered. Biochemical criteria, deduced from a numerical taxonomic study of phenotypic characteristics, and serological reactions allowed discrimination of the strains belonging to the six genomic species. Thus, it is proposed that the strains clustered in these six genomic species be assigned to the species Dickeya zeae sp. nov. (type strain CFBP 2052T=NCPPB 2538T), Dickeya dadantii sp. nov. (type strain CFBP 1269T=NCPPB 898T), Dickeya chrysanthemi comb. nov. (subdivided into two biovars, bv. chrysanthemi and bv. parthenii), Dickeya dieffenbachiae sp. nov. (type strain CFBP 2051T=NCPPB 2976T), Dickeya dianthicola sp. nov. (type strain CFBP 1200T=NCPPB 453T) and Dickeya paradisiaca comb. nov., respectively.
338 citations
TL;DR: It is demonstrated that there have been at least three independent introductions from North America during the past two decades, which raises questions about changing circumstances that have enabled a sudden burst of transatlantic introductions.
Abstract: The invasion of Europe by the western corn rootworm, North America's most destructive corn pest, is ongoing and represents a serious threat to European agriculture. Because this pest was initially introduced in Central Europe, it was believed that subsequent outbreaks in Western Europe originated from this area. Using model-based Bayesian analyses of the genetic variability of the western corn rootworm, we demonstrate that this belief is false: There have been at least three independent introductions from North America during the past two decades. This result raises questions about changing circumstances that have enabled a sudden burst of transatlantic introductions.
TL;DR: This work shows that the discrepancy between laboratory and seismological results can be resolved if thermal pressurization of the pore fluid is the slip-weakening mechanism, and indicates that a planar fault segment with an impermeable and narrow slip zone will become very unstable during slip and is likely to be the site of a seismic asperity.
Abstract: An earthquake occurs when a fault weakens during the early portion of its slip at a faster rate than the release of tectonic stress driving the fault motion. This slip weakening occurs over a critical distance, D(c). Understanding the controls on D(c) in nature is severely limited, however, because the physical mechanism of weakening is unconstrained. Conventional friction experiments, typically conducted at slow slip rates and small displacements, have obtained D(c) values that are orders of magnitude lower than values estimated from modelling seismological data for natural earthquakes. Here we present data on fluid transport properties of slip zone rocks and on the slip zone width in the centre of the Median Tectonic Line fault zone, Japan. We show that the discrepancy between laboratory and seismological results can be resolved if thermal pressurization of the pore fluid is the slip-weakening mechanism. Our analysis indicates that a planar fault segment with an impermeable and narrow slip zone will become very unstable during slip and is likely to be the site of a seismic asperity.
TL;DR: The results demonstrate that contrary to the findings of earlier electrophysiologic studies carried out on ventral tegmental area dopaminergic neurons, changes in the release of dopamine in projection areas occur across the sleep–wake cycle.
Abstract: We used intracerebral microdialysis coupled with electrophysiologic recordings to determine relative changes in the concentrations of several neurotransmitters in the medial prefrontal cortex and nucleus accumbens of freely moving rats during waking, slow-wave sleep, and rapid eye movement (REM) sleep. The concentrations of noradrenaline, dopamine, glutamate, and aspartate in 2-min dialysate samples were analyzed by capillary electrophoresis combined with laser-induced fluorescence detection. Changes in glutamate and aspartate concentrations were found only in the nucleus accumbens, in which a decrease was obtained during both slow-wave sleep and REM sleep compared to waking. A progressive reduction in the release of noradrenaline was observed from waking to REM sleep in both structures. In contrast, dopamine concentrations were higher during waking and REM sleep compared to that during slow-wave sleep. The latter results demonstrate that contrary to the findings of earlier electrophysiologic studies carried out on ventral tegmental area dopaminergic neurons, changes in the release of dopamine in projection areas occur across the sleep-wake cycle. The elevated levels of dopamine during waking and REM sleep in the medial prefrontal cortex and the nucleus accumbens could result from changes during these two states in afferent modulation at the level of cell bodies or at the level of dopaminergic terminals.
12 Dec 2005
TL;DR: In this article, two different non-linear complementary filters are proposed: Direct complementary filter and Passive nonlinear complementary filter, which evolve explicity on the special orthogonal group SO(3) and can be expressed in quaternion form for easy implementation.
Abstract: This paper considers the problem of obtaining high quality attitude extraction and gyros bias estimation from typical low cost intertial measurement units for applications in control of unmanned aerial vehiccles. Two different non-linear complementary filters are proposed: Direct complementary filter and Passive non-linear complementary filter. Both filters evolve explicity on the special orthogonal group SO(3) and can be expressed in quaternion form for easy implementation. An extension to the passive ocmplementary filter is proposed to provide adaptive gyro bias estimation.
IPG Photonics1, University of Nice Sophia Antipolis2, University of Montpellier3, Centre national de la recherche scientifique4, University of Bordeaux5, University of Savoy6, Istanbul Technical University7, TÜBİTAK Marmara Research Center8, Lamont–Doherty Earth Observatory9, Collège de France10, General Directorate of Mineral Research and Exploration11
TL;DR: The MARMARASCARPS cruise using an unmanned submersible (ROV) provides direct observations to study the fine-scale morphology and geology of those scarps, their distribution, and geometry as discussed by the authors.
Abstract: Earthquake scarps associated with recent historical events have been found on the floor of the Sea of Marmara, along the North Anatolian Fault (NAF). The MARMARASCARPS cruise using an unmanned submersible (ROV) provides direct observations to study the fine-scale morphology and geology of those scarps, their distribution, and geometry. The observations are consistent with the diversity of fault mechanisms and the fault segmentation within the north Marmara extensional step-over, between the strike-slip Ganos and Izmit faults. Smaller strike-slip segments and pull-apart basins alternate within the main step-over, commonly combining strike-slip and extension. Rapid sedimentation rates of 1?3 mm/yr appear to compete with normal faulting components of up to 6 mm/yr at the pull-apart margins. In spite of the fast sedimentation rates the submarine scarps are preserved and accumulate relief. Sets of youthful earthquake scarps extend offshore from the Ganos and Izmit faults on land into the Sea of Marmara. Our observations suggest that they correspond to the submarine ruptures of the 1999 Izmit (Mw 7.4) and the 1912 Ganos (Ms 7.4) earthquakes. While the 1999 rupture ends at the immediate eastern entrance of the extensional Cinarcik Basin, the 1912 rupture appears to have crossed the Ganos restraining bend into the Sea of Marmara floor for 60 km with a right-lateral slip of 5 m, ending in the Central Basin step-over. From the Gulf of Saros to Marmara the total 1912 rupture length is probably about 140 km, not 50 km as previously thought. The direct observations of submarine scarps in Marmara are critical to defining barriers that have arrested past earthquakes as well as defining a possible segmentation of the contemporary state of loading. Incorporating the submarine scarp evidence modifies substantially our understanding of the current state of loading along the NAF next to Istanbul. Coulomb stress modeling shows a zone of maximum loading with at least 4?5 m of slip deficit encompassing the strike-slip segment 70 km long between the Cinarcik and Central Basins. That segment alone would be capable of generating a large-magnitude earthquake (Mw 7.2). Other segments in Marmara appear less loaded.
TL;DR: A molecular model is proposed for the functional coupling of a rhodopsin monomeric unit with a G-protein heterotrimer and should be valid even for GPCRs that exist as structural dimers.
Abstract: Rhodopsin, the first purified G-protein-coupled receptor (GPCR), was characterized as a functional monomer 30 year ago, but dimerization of GPCRs recently became the new paradigm of signal transduction. It has even been claimed, on the basis of recent biophysical and biochemical studies, that this new concept could be extended to higher-order oligomerization. Here this view is challenged. The new studies of rhodopsin and other simple (class 1a) GPCRs solubilized in detergent are re-assessed and are compared to the earlier classical studies of rhodopsin and other membrane proteins solubilized in detergent. The new studies are found to strengthen rather than invalidate the conclusions of the early ones and to support a monomeric model for rhodopsin and other class 1a GPCRs. A molecular model is proposed for the functional coupling of a rhodopsin monomeric unit with a G-protein heterotrimer. This model should be valid even for GPCRs that exist as structural dimers.
TL;DR: Clinical description and biological correlates of the major behavioral and psychological symptomatology in AD are presented and an individually tailored approach taking all these aspects into account is warranted.
01 Jan 2005
TL;DR: A condensed representation for association rules is defined using a semantic based on the closure of the Galois connection that contains the non-redundant association rules having minimal antecedent and maximal consequent, called min-max association rules.
Abstract: Association rule extraction from operational datasets often produces several tens of thousands, and even millions, of association rules. Moreover, many of these rules are redundant and thus useless. Using a semantic based on the closure of the Galois connection, we define a condensed representation for association rules. This representation is characterized by frequent closed itemsets and their generators. It contains the non-redundant association rules having minimal antecedent and maximal consequent, called min-max association rules. We think that these rules are the most relevant since they are the most general non-redundant association rules. Furthermore, this representation is a basis, i.e., a generating set for all association rules, their supports and their confidences, and all of them can be retrieved needless accessing the data. We introduce algorithms for extracting this basis and for reconstructing all association rules. Results of experiments carried out on real datasets show the usefulness of this approach. In order to generate this basis when an algorithm for extracting frequent itemsets--such as Apriori for instance--is used, we also present an algorithm for deriving frequent closed itemsets and their generators from frequent itemsets without using the dataset.
TL;DR: In this article, the authors use phase diagrams for a H2O-satured mantle peridotite and a gabbroic crust to determine at each time step the amount of water released or absorbed by each unit of rock.
TL;DR: Given the results obtained with animal models, PPARdelta agonists may have therapeutic usefulness in metabolic syndrome by increasing fatty acid consumption in skeletal muscle and adipose tissue by controlling the number of oxidative myofibers.
TL;DR: In this paper, a dual-band circularly polarized patch antenna dedicated to satellite communications is presented, which is obtained by inserting a small X-band microstrip patch antenna into a large L-band one.
Abstract: This letter presents a dual-band circularly polarized patch antenna dedicated to satellite communications. The dual-band behavior is obtained by inserting a small X-band microstrip patch antenna into a large L-band one. Both patches are printed on the same substrate and fed by electromagnetic coupling through two perpendicular slots etched in their ground planes. These slots are fed by two different 90/spl deg/ microstrip branch-line couplers printed on a stacked lower substrate. A prototype of the antenna was realized with a 1.5-mm-thick upper layer substrate and a 0.758-mm-thick feed layer substrate, both of the same dielectric material with a relative permittivity of /spl epsiv//sub r/=2.22. Simulation and measurement results are presented, showing this compact dual-band antenna achieves the required Meteosat specifications in terms of frequency bandwidth, circular polarization bandwidth, and isolation between the two communication bands.
TL;DR: In this paper, the authors computed temporal linear stability modes depending on two space directions for a two-dimensional boundary-layer flow along a flat plate and showed that an appropriate superposition of a moderate number of temporal modes gives rise to a spatially localized wave packet, starting at inflow and exhibiting transient temporal growth when evolving downstream along the plate.
Abstract: Temporal linear stability modes depending on two space directions are computed for a two-dimensional boundary-layer flow along a flat plate. The spatial structure of each individual temporally stable mode is shown to be reminiscent of the spatial exponential growth of perturbations along the flat plate, as predicted by local analyses. It is shown using an optimal temporal growth analysis, that an appropriate superposition of a moderate number of temporal modes gives rise to a spatially localized wave packet, starting at inflow and exhibiting transient temporal growth when evolving downstream along the plate. This wave packet is in qualitative agreement with the convectively unstable disturbance observed when solving the Navier–Stokes equations for an equivalent initial condition.
Victoria University of Wellington1, University of Toulouse2, Tamkang University3, University of the Philippines Diliman4, Massey University5, University of Nice Sophia Antipolis6, University of Illinois at Urbana–Champaign7, University of Malaya8, University of Melbourne9, Swinburne University of Technology10, University of Tokyo11, Hokkaido University12
TL;DR: The authors assessed social representations of world history using the open-ended questions, "What are the most important events in world history?" and "Who were the most influential persons in World History in the last 1000 years?" Data from 6 Asian and 6 Western samples showed cross-cultural consensus.
Abstract: Social representations of world history were assessed using the open-ended questions, “What are the most important events in world history?” and “Who are the most influential persons in world history in the last 1000 years?” Data from 6 Asian and 6 Western samples showed cross-cultural consensus. Historical representations were (a) focused on the recent past, (b) centered around politics and war, and (c) dominated by the events of the World Wars and (d) the individual Hitler, who was universally perceived as negative. (e) Representations were more Eurocentric than ethnocentric. (f) The importance of economics and science was underrepresented. (g) Most cultures nominated people (more than events) idiosyncratic to their own culture. These data reflect power relations in the world and provide resources and constraints for the conduct of international relations. The degree of cross-cultural consensus suggests that hybridity across Eastern and Western cultures in the representation of knowledge may be underestimated.
TL;DR: In this paper, the authors propose a method to solve the problem of homonymity of homophily in the context of homomorphic data, and no abstracts are available.
Abstract: No abstract available.
TL;DR: This paper synthesises the existing methods applied to monitor P. oceanica meadows, identifies the most suitable techniques and suggests future research directions, and shows the interest of a practical guide that describes, in a standardized way, the most useful techniques enabling P. Oceanica meadow to be used as an environmental descriptor.
TL;DR: Comparative studies between symbiotic and non-symbiotic sea anemones show striking differences in their response to oxidative stress, suggesting symbiotic cells adapt to stress while non-Symbiotic cells remain acutely sensitive to stress.
Abstract: Cnidarians in symbiosis with photosynthetic protists must withstand daily hyperoxic/anoxic transitions within their host cells. Comparative studies between symbiotic (Anemonia viridis) and non-symbiotic (Actinia schmidti) sea anemones show striking differences in their response to oxidative stress. First, the basal expression of SOD is very different. Symbiotic animal cells have a higher isoform diversity (number and classes) and a higher activity than the non-symbiotic cells. Second, the symbiotic animal cells of A. viridis also maintain unaltered basal values for cellular damage when exposed to experimental hyperoxia (100% O(2)) or to experimental thermal stress (elevated temperature +7 degrees C above ambient). Under such conditions, A. schmidti modifies its SOD activity significantly. Electrophoretic patterns diversify, global activities diminish and cell damage biomarkers increase. These data suggest symbiotic cells adapt to stress while non-symbiotic cells remain acutely sensitive. In addition to being toxic, high O(2) partial pressure (P(O(2))) may also constitute a preconditioning step for symbiotic animal cells, leading to an adaptation to the hyperoxic condition and, thus, to oxidative stress. Furthermore, in aposymbiotic animal cells of A. viridis, repression of some animal SOD isoforms is observed. Meanwhile, in cultured symbionts, new activity bands are induced, suggesting that the host might protect its zooxanthellae in hospite. Similar results have been observed in other symbiotic organisms, such as the sea anemone Aiptasia pulchella and the scleractinian coral Stylophora pistillata. Molecular or physical interactions between the two symbiotic partners may explain such variations in SOD activity and might confer oxidative stress tolerance to the animal host.
TL;DR: In this paper, a multidisciplinary approach dealing with three-dimensional delay time tomography and rock physics characterization has been followed to explore the structure of the Campi Flegrei Caldera as well as the role of hydrothermal fluids on velocity changes.
Abstract: [1] The Campi Flegrei (CF) Caldera experiences dramatic ground deformations unsurpassed anywhere in the world. The source responsible for this phenomenon is still debated. With the aim of exploring the structure of the caldera as well as the role of hydrothermal fluids on velocity changes, a multidisciplinary approach dealing with three-dimensional delay time tomography and rock physics characterization has been followed. Selected seismic data were modeled by using a tomographic method based on an accurate finite difference travel time computation which simultaneously inverts P wave and S wave first-arrival times for both velocity model parameters and hypocenter locations. The retrieved P wave and S wave velocity images as well as the deduced V p /V s images were interpreted by using experimental measurements of rock physical properties on CF samples to take into account steam/water phase transition mechanisms affecting P wave and S wave velocities. Also, modeling of petrophysical properties for site-relevant rocks constrains the role of overpressured fluids on velocity. A flat and low V p /V s anomaly lies at 4 km depth under the city of Pozzuoli. Earthquakes are located at the top of this anomaly. This anomaly implies the presence of fractured overpressured gas-bearing formations and excludes the presence of melted rocks. At shallow depth, a high V p /V s anomaly located at 1 km suggests the presence of rocks containing fluids in the liquid phase. Finally, maps of the V p *V s product show a high V p * V s horseshoe-shaped anomaly located at 2 km depth. It is consistent with gravity data and well data and might constitute the on-land remainder of the caldera rim, detected below sea level by tomography using active source seismic data.
TL;DR: Two gamma- and UV-radiation-tolerant, Gram-negative, rod-shaped bacterial strains, VCD115T and VCD117, were isolated from a mixture of sand samples collected in the Sahara Desert after exposure of the sand to 15 kGy gamma radiation, showing affiliation to the genus Deinococcus.
Abstract: Two gamma- and UV-radiation-tolerant, Gram-negative, rod-shaped bacterial strains, VCD115T and VCD117, were isolated from a mixture of sand samples collected in the Sahara Desert in Morocco and Tunisia, after exposure of the sand to 15 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA gene sequences and DNA–DNA hybridizations showed that VCD115T and VCD117 are members of a novel species belonging to the genus Deinococcus, with Deinococcus grandis as its closest relative. The DNA G+C contents of VCD115T and VCD117 are 59·8 and 60·6 mol%, respectively. The major fatty acids (straight-chain 15 : 1, 16 : 1, 17 : 1 and 16 : 0), polar lipids (dominated by phosphoglycolipids and glycolipids) and quinone type (MK-8) support the affiliation to the genus Deinococcus. The strains did not grow on rich medium such as trypticase soy broth (TSB), but did grow as whitish colonies on tenfold-diluted TSB. The genotypic and phenotypic properties allowed differentiation of VCD115T and VCD117 from recognized Deinococcus species. Strains VCD115T and VCD117 are therefore identified as representing a novel species, for which the name Deinococcus deserti sp. nov. is proposed, with the type strain VCD115T (=DSM 17065T=LMG 22923T).
TL;DR: The existence of standing waves on the surface of an infinitely deep perfect fluid under gravity is established in this article, where the existence question is reduced to estimating the inverses of linearized operators at non-zero points.
Abstract: The existence of two-dimensional standing waves on the surface of an infinitely deep perfect fluid under gravity is established. When formulated as a second-order equation for a real-valued function w on the 2-torus and a positive parameter μ, the problem is fully nonlinear (the highest order x-derivative appears in the nonlinear term but not in the linearization at 0) and completely resonant (there are infinitely many linearly independent eigenmodes of the linearization at 0 for all rational values of the parameter μ). Moreover, for any prescribed order of accuracy there exists an explicit approximate solution of the nonlinear problem in the form of a trigonometric polynomial. Using a Nash-Moser method to seek solutions of the nonlinear problem as perturbations of the approximate solutions, the existence question can be reduced to one of estimating the inverses of linearized operators at non-zero points. After changing coordinates these operators become first order and non-local in space and second order in time. After further changes of variables the main parts become diagonal with constant coefficients and the remainder is regularizing, or quasi-one-dimensional in the sense of [22]. The operator can then be inverted for two reasons. First, the explicit formula for the approximate solution means that, restricted to the infinite-dimensional kernel of the linearization at zero, the inverse exists and can be estimated. Second, the small-divisor problems that arise on the complement of this kernel can be overcome by considering only particular parameter values selected according to their Diophantine properties. A parameter-dependent version of the Nash-Moser implicit function theorem now yields the existence of a set of unimodal standing waves on flows of infinite depth, corresponding to a set of values of the parameter μ>1 which is dense at 1. Unimodal means that the term of smallest order in the amplitude is cos x cos t, which is one of many eigenfunctions of the completely resonant linearized problem.
TL;DR: The Isernia travertines are not associated with hot water springs and indicate that the area was frequented at the end of an Interglacial period as discussed by the authors, which indicates that the human frequentation occurred at the beginning of the Middle Pleistocene.