Ambient vibration recording for single-station, array and building studies made simple : CityShark II

This article describes an improved data acquisition system from a previous system dedicated to one-sensor site studies, aimed at recording ambient vibrations (microtremors). A multi-channel and/or remote triggering system is proposed. The system was conceived by IRD-Leas, France, and used at ISTerre, France, for research activities. The size, weight of this high quality system and its autonomy (no need to be connected to a laptop) make it a real portable device. The sys- tem acquires data with 24-bit delta-sigma ADCs in the 10 - 1000 sps range at 10 - 20 bit resolution on up to 18 channels in the multi-channel version. The input stage dynamics is available at ±2.5 V or ±5 V. The dynamic range varies, for example, from 108 dB at 100 sps to 90 dB at 250 sps. Gain is selectable from 1 (0 dB) to 8192 (78 dB) by powers of two (6 dB). Its very low level of internal noise allows recording of very low tension signals without missing code. Con- tinuous recording and GPS may also be implemented in the system. While primarily dedicated to ambient vibration recordings, this system can be connected to any type of device delivering an output tension in the ±5 V range

Influence of thermal and mechanical cracks on permeability and elastic wave velocities in a basalt from Mt. Etna volcano subjected to elevated pressure

We report simultaneous laboratory measurements of seismic velocities and fluid permeability on lava flow basalt from Etna (Italy). Results were obtained for dry and saturated samples deformed under triaxial compression. During each test, the effective pressure was first increased up to 190 MPa to investigate the effect of pre-existing crack closure on seismic properties. Then, the effective pressure was unloaded down to 20 MPa, a pressure which mirrors the stress field acting under a lava pile of approximately 1.5–2 km thick, and deviatoric stress was increased until failure of the specimens. Using an effective medium model, the measured elastic wave velocities were inverted in terms of two crack densities: ρi the crack density of the pre-existing thermal cracks and ρv the crack density of the stress-induced cracks. In addition a link was established between elastic properties (elastic wave velocities Vp and Vs) and permeability using a statistical permeability model. Our results show that the velocities increase with increasing hydrostatic pressure up to 190 MPa, due to the closure of the pre-existing thermal cracks. This is interpreted by a decrease of the crack density ρi from ~1 to 0.2. The effect of pre-existing cracks closure is also highlighted by the permeability evolution which decreases of more than two orders of magnitude. Under deviatoric loading, the velocities signature is interpreted, in the first stage of the loading, by the closure of the pre-existing thermal cracks. However, with increasing deviatoric loading newly-formed vertical cracks nucleate and propagate. This is clearly seen from the velocity signature and its interpretation in term of crack density, the location of the acoustic emission sources, and from microstructural observations. This competition between pre-existing cracks closure and propagation of vertical cracks is also seen from the permeability evolution, and our study shows that mechanically-induced cracks has lesser influence on permeability change than pre-existing thermal cracks

Dollo parsimony overestimates ancestral gene content reconstructions

Ancestral reconstruction is a widely-used technique that has been applied to understand the evolutionary history of gain and loss of gene families. Ancestral gene content can be reconstructed via different phylogenetic methods, but many current and previous studies employ Dollo parsimony. We hypothesize that Dollo parsimony is not appropriate for ancestral gene content reconstruction inferences based on sequence homology, as Dollo parsimony is derived from the assumption that a complex character cannot be regained. This premise does not accurately model molecular sequence evolution, in which false orthology can result from sequence convergence or lateral gene transfer. The aim of this study is to test Dollo parsimony's suitability for ancestral gene content reconstruction and to compare its inferences with a maximum likelihood-based approach which allows a gene family to be gained more than once within a tree. We first compared the performance of the two approaches on a series of artificial datasets each of 5,000 genes that were simulated according to a spectrum of evolutionary rates without gene gain or loss, so that inferred deviations from the true gene count would arise only from errors in orthology inference and ancestral reconstruction. Next, we reconstructed protein domain evolution on a phylogeny representing known eukaryotic diversity. We observed that Dollo parsimony produced numerous ancestral gene content overestimations, especially at nodes closer to the root of the tree. These observations led us to the conclusion that, confirming our hypothesis, Dollo parsimony is not an appropriate method for ancestral reconstruction studies based on sequence homology

Minerals and vitamins in bone health: the potential value of dietary enhancement

Nutrition is important to bone health, and a number of minerals and vitamins have been identified as playing a potential role in the prevention of bone diseases, particularly osteoporosis. Despite this, there is currently no consensus on maximum levels to allow in food or as dietary supplements. The benefits of supplementation of populations at risk of osteoporosis with Ca and vitamin D are well established. Prolonged supplementation of Ca and vitamin D in elderly has been shown to prevent bone loss, and in some intervention studies to prevent fragility fractures. Although P is essential to bone health, the average intake is considered to be more than sufficient and supplementation could raise intake to adverse levels. The role of vitamin K in bone health is less well defined, though it may enhance the actions of Ca and vitamin D. Sr administered in pharmacological doses as the ranelate salt was shown to prevent fragility fractures in postmenopausal osteoporosis. However, there is no hard evidence that supplementation with Sr salts would be beneficial in the general population. Mg is a nutrient implicated in bone quality, but the benefit of supplementation via foodstuffs remains to be established. A consensus on dietary supplementation for bone health should balance the risks, for example, exposure of vulnerable populations to values close to maximal tolerated doses, against evidence for benefits from randomised clinical trials, such as those for Ca and vitamin D. Feedback from community studies should direct further investigations and help formulate a consensus on dietary supplementation for bone healt

Cosmetics Alter Biologically-Based Factors of Beauty: Evidence from Facial Contrast

The use of cosmetics by women seems to consistently increase their attractiveness. What factors of attractiveness do cosmetics alter to achieve this? Facial contrast is a known cue to sexual dimorphism and youth, and cosmetics exaggerate sexual dimorphisms in facial contrast. Here, we demonstrate that the luminance contrast pattern of the eyes and eyebrows is consistently sexually dimorphic across a large sample of faces, with females possessing lower brow contrasts than males, and greater eye contrast than males. Red-green and yellow-blue color contrasts were not found to differ consistently between the sexes. We also show that women use cosmetics not only to exaggerate sexual dimorphisms of brow and eye contrasts, but also to increase contrasts that decline with age. These findings refine the notion of facial contrast, and demonstrate how cosmetics can increase attractiveness by manipulating factors of beauty associated with facial contrast

Intercultural New Media Studies: The Next Frontier in intercultural Communication

New media (ICT\u27s) are transforming communication across cultures. Despite this revolution in cross cultural contact, communication researchers have largely ignored the impact of new media on intercultural communication. This groundbreaking article defines the parameters of a new field of inquiry called Intercultural New Media Studies (INMS), which explores the intersection between ICT\u27s and intercultural communication. Composed of two research areas—(1) new media and intercultural communication theory and (2) culture and new media—INMS investigates new digital theories of intercultural contact as well as refines and expands twentieth-century intercultural communication theories, examining their salience in a digital world. INMS promises to increase our understanding of intercultural communication in a new media age and is the next frontier in intercultural communication

Laboratory micro-seismic signature of shear faulting and fault slip in shale

This article reports the results of a triaxial deformation experiment conducted on a transversely isotropic shale specimen. This specimen was instrumented with ultrasonic transducers to monitor the evolution of the micro-seismic activity induced by shear faulting (triaxial failure) and subsequent fault slip at two different rates. The strain data demonstrate the anisotropy of the mechanical (quasi-static) compliance of the shale; the P-wave velocity data demonstrate the anisotropy of the elastic (dynamic) compliance of the shale. The spatio-temporal evolution of the micro-seismic activity suggests the development of two distinct but overlapping shear faults, a feature similar to relay ramps observed in large-scale structural geology. The shear faulting of the shale specimen appears quasi-aseismic, at least in the 0.5 MHz range of sensitivity of the ultrasonic transducers used in the experiment. Concomitantly, the rate of micro-seismic activity is strongly correlated with the imposed slip rate and the evolution of the axial stress. The moment tensor inversion of the focal mechanism of the high quality micro-seismic events recorded suggests a transition from a non-shear dominated to a shear dominated micro-seismic activity when the rock evolves from initial failure to larger and faster slip along the fault. The frictional behaviour of the shear faults highlights the possible interactions between small asperities and slow slip of a velocity-strengthening fault, which could be considered as a realistic experimental analogue of natural observations of non-volcanic tremors and (very) low-frequency earthquakes triggered by slow slip events

Facial Cosmetics and Attractiveness: Comparing the Effect Sizes of Professionally-Applied Cosmetics and Identity

Forms of body decoration exist in all human cultures. However, in Western societies, women are more likely to engage in appearance modification, especially through the use of facial cosmetics. How effective are cosmetics at altering attractiveness? Previous research has hinted that the effect is not large, especially when compared to the variation in attractiveness observed between individuals due to differences in identity. In order to build a fuller understanding of how cosmetics and identity affect attractiveness, here we examine how professionally-applied cosmetics alter attractiveness and compare this effect with the variation in attractiveness observed between individuals. In Study 1, 33 YouTube models were rated for attractiveness before and after the application of professionally-applied cosmetics. Cosmetics explained a larger proportion of the variation in attractiveness compared with previous studies, but this effect remained smaller than variation caused by differences in attractiveness between individuals. Study 2 replicated the results of the first study with a sample of 45 supermodels, with the aim of examining the effect of cosmetics in a sample of faces with low variation in attractiveness between individuals. While the effect size of cosmetics was generally large, between-person variability due to identity remained larger. Both studies also found interactions between cosmetics and identity-more attractive models received smaller increases when cosmetics were worn. Overall, we show that professionally- applied cosmetics produce a larger effect than self-applied cosmetics, an important theoretical consideration for the field. However, the effect of individual differences in facial appearance is ultimately more important in perceptions of attractiveness

Evolutionary Mechanisms of Long-Term Genome Diversification Associated With Niche Partitioning in Marine Picocyanobacteria.

Marine picocyanobacteria of the genera Prochlorococcus and Synechococcus are the most abundant photosynthetic organisms on Earth, an ecological success thought to be linked to the differential partitioning of distinct ecotypes into specific ecological niches. However, the underlying processes that governed the diversification of these microorganisms and the appearance of niche-related phenotypic traits are just starting to be elucidated. Here, by comparing 81 genomes, including 34 new Synechococcus, we explored the evolutionary processes that shaped the genomic diversity of picocyanobacteria. Time-calibration of a core-protein tree showed that gene gain/loss occurred at an unexpectedly low rate between the different lineages, with for instance 5.6 genes gained per million years (My) for the major Synechococcus lineage (sub-cluster 5.1), among which only 0.71/My have been fixed in the long term. Gene content comparisons revealed a number of candidates involved in nutrient adaptation, a large proportion of which are located in genomic islands shared between either closely or more distantly related strains, as identified using an original network construction approach. Interestingly, strains representative of the different ecotypes co-occurring in phosphorus-depleted waters (Synechococcus clades III, WPC1, and sub-cluster 5.3) were shown to display different adaptation strategies to this limitation. In contrast, we found few genes potentially involved in adaptation to temperature when comparing cold and warm thermotypes. Indeed, comparison of core protein sequences highlighted variants specific to cold thermotypes, notably involved in carotenoid biosynthesis and the oxidative stress response, revealing that long-term adaptation to thermal niches relies on amino acid substitutions rather than on gene content variation. Altogether, this study not only deciphers the respective roles of gene gains/losses and sequence variation but also uncovers numerous gene candidates likely involved in niche partitioning of two key members of the marine phytoplankton

Work-related risk factors for incidence of lateral epicondylitis in a large working population

Objectives This study aims to estimate the association between repeated measures of occupational risk factors and the incidence of lateral epicondylitis in a large working population. Methods A total of 3710 workers in a French region were included in 2002–2005, and among them 1046 had a complete follow-up in 2007–2010. At both stages, occupational health physicians assessed the presence of lateral epicondylitis and workers self-reported their occupational exposures. Poisson models were performed to assess the incidence rate ratios (IRR) separately by sex using multiple imputed data. Results The annual incidence rate of lateral epicondylitis was estimated as 1.0 [95% confidence interval (95% CI) 0.7–1.3] per 100 workers among men and 0.9 (95% CI 0.6–1.3) among women. Workers aged >45 years had higher incidence than those aged <30 years (significant at 10%). Among men, high physical exertion combined with elbow flexion/extension or extreme wrist bending (>2 hours/day) was a risk factor, with an age-adjusted IRR of 3.2 (95% CI 1.5–6.4) for workers exposed at both questionnaires [3.3 (95% CI 1.4–7.6) among women]. Conclusions This study highlights the importance of temporal dimensions for occupational risk factors on the incidence of lateral epicondylitis. Further research should evaluate the risk associated with the duration and repetition of occupational exposure on the incidence of lateral epicondylitis