Search results for " Sam"
showing 10 items of 1096 documents
Defaunation and biomass collapse of mammals in the largest Atlantic forest remnant
2016
Large continuous rainforests are the main hope for sustaining the population of large-bodied vertebrates that cannot cope with fragmentation or unsustainable hunting. The Brazilian Atlantic forest is considered a biodiversity hotspot and although highly fragmented, it still contains large forest patches that may be important for the conservation of mammals that require large areas. Here, we estimated species richness, density and biomass of medium- and large-sized mammals along the largest remnant of the Atlantic rainforest, Brazil (the Serra do Mar bioregion), an estimated area of 8000 km2. We recorded 44 species based on 4090 km of diurnal line transects and camera traps, animal tracks an…
The "Tracked Roaming Transect" and distance sampling methods increase the efficiency of underwater visual censuses.
2018
Underwater visual census (UVC) is the most common approach for estimating diversity, abundance and size of reef fishes in shallow and clear waters. Abundance estimation through UVC is particularly problematic in species occurring at low densities and/or highly aggregated because of their high variability at both spatial and temporal scales. The statistical power of experiments involving UVC techniques may be increased by augmenting the number of replicates or the area surveyed. In this work we present and test the efficiency of an UVC method based on diver towed GPS, the Tracked Roaming Transect (TRT), designed to maximize transect length (and thus the surveyed area) with respect to diving …
Only Females Oviposit: Chemical Discrimination of Adult Stink Bug Sex by the Egg Parasitoid Trissolcus japonicus
2021
Egg parasitoids foraging for suitable hosts scattered in the environment rely mainly on chemical cues. Elucidating the chemical ecology of natural enemies is important in the development of effective and successful strategies for conservation biological control. In this context, the host cuticular hydrocarbons, which are exploited by several species of egg parasitoids as contact kairomones, could be used to retain them by providing information about the presence and the sex of adults of the target species: sex is important because only females of the host species lay the eggs that can be subsequently utilized for parasitoid reproduction. However, the chemical basis of host sex discriminatio…
State Observer with Round-Robin Aperiodic Sampled Measurements with Jitter
2021
International audience; A sampled-data observer is proposed for linear continuous-time systems whose outputs are sequentially sampled via non-uniform sampling intervals repeating a prescribed Round-Robin sequence. With constant sampling intervals (jitter-free case) we provide constructive necessary and sufficient conditions for the design of an asymptotic continuous-discrete observer whose estimation error is input-to-state stable (ISS) from process disturbances and measurement noise. We use a time-varying gain depending on the elapsed time since the last measurement. With non-constant sampling intervals (jitter-tolerant case), our design conditions are only sufficient. A suspension system …
Global sensitivity analysis in welding simulations -- what are the material data you really need ?
2011
In this paper, the sensitivity analysis methodology is applied to numerical welding simulation in order to rank the importance of input variables on the outputs of the code like distorsions or residual stresses. The numerical welding simulation uses the finite element method, with a thermal computation followed by a mechanical one. Classically, a local sensitivity analysis is performed, hence the validity of the results is limited to the neighbourhood of a nominal point, and cross effects cannot be detected. This study implements a global sensitivity analysis which allows to screen the whole material space of the steel family mechanical properties. A set of inputs of the mechanical model-ma…
BIOAEROSOL
2017
Cultural heritage constitutive materials can provide excellent substrates for microbial colonisation, highly influenced by thermo-hygrometric parameters. In cultural heritage-related environments, a detrimental microbial load may be present both on manufact surface and in the aerosol. Confined environments (museums, archives, deposits, caves, hypogea) have peculiar structures and dif- ferent thermo-hygrometric parameters, influencing the development of a wide range of microbial species, able to induce artefact biodeterioration and to release biological particles in the aerosol (spores, cellular debrides, toxins, allergens) potentially dangerous for the human health (visitors/users). In orde…
Development of a sensory tool to assess overall liking for the fatty, salty and sweet sensations
2016
Abstract Understanding the origin of the overconsumption of too high levels of sucrose, sodium chloride and lipids in foods raises the question of the influence of the hedonics for these sensations. To better understand this relationship, a sensory tool that enables measurement of liking towards sweet, salty or fatty sensations is required. This liking towards a sensation has to be understood as an overall attractiveness of the sensation. Instruments already existing were unsatisfactory as including a limited number of foods not representative of the overall sensation. A set of hedonic tests, named PrefSens, was developed to measure an overall liking for fatty, salty or sweet sensations. Ea…
Simultaneous Determination of Caffeine and Chlorogenic Acids in Green Coffee by UV/Vis Spectroscopy
2017
A simple method for the simultaneous determination of caffeine and chlorogenic acids content in green coffee was reported. The method was based on the use of UV/Vis absorption. It is relevant that the quantification of both caffeine and chlorogenic acids was performed without their preliminary chemical separation despite their spectral overlap in the range 250–350 nm. Green coffee was extracted with 70% ethanol aqueous solution; then the solution was analyzed by spectroscopy. Quantitative determination was obtained analytically through deconvolution of the absorption spectrum and by applying the Lambert-Beer law. The bands used for the deconvolution were the absorption bands of both caffein…
Measuring Orthorexia Nervosa: Psychometric Limitations of the ORTO-15.
2017
AbstractOrthorexia nervosa has recently been defined as excessive preoccupation with healthy eating, causing significant nutritional deficiencies and social and personal impairments. The ORTO-15 is the most widely used instrument to evaluate orthorexia nervosa, although previous studies obtained inconsistent results about its psychometric properties, and there are no data on the Spanish version. Thus, the main objective of the present study was to analyze the psychometric properties of the Spanish adaptation of the ORTO-15. In order to cross-validate the results, two independent samples were used (Sample 1: n = 807, 74.1% women; Sample 2: n = 242, 63.2% women). The results did not support t…
Stability of a Split Streptomycin Binding Aptamer
2016
Here we investigated the stability of an aptamer, which is formed by two RNA strands and binds the antibiotic streptomycin. Molecular dynamics simulations in aqueous solution confirmed the geometry and the pattern of hydrogen bond interactions that was derived from the crystal structure (1NTB). The result of umbrella sampling simulations indicated a favored streptomycin binding with a free energy of ΔGbind° = −101.7 kJ mol–1. Experimentally, the increase in oligonucleotide stability upon binding of streptomycin was probed by single-molecule force spectroscopy. Rate dependent force spectroscopy measurements revealed a decrease in the natural off-rate (koff-COMPLEX = 0.22 ± 0.16 s–1) for the …