384 research outputs found
Estimation of <i>Vs</i> profile using its natural frequency and Rayleigh-wave dispersion characteristics
International audienceThe evaluation of the natural frequency of random Vs profiles before analyzing the fundamental Rayleigh-wave dispersion characteristics is proposed in this paper. The inclusion of this parameter optimizes the effectiveness of random inverse searching to estimate Vs profiles. To demonstrate this method, a numerical test was performed using the "experimental" Rayleigh-wave dispersion curve obtained for a fictitious TEST site
Analysis of IgE turnover in non-sensitized and sensitized rats.
BACKGROUND: Although the levels of immunoglobulin E (IgE) in the circulating blood are often elevated in patients with allergic diseases, such levels cannot always be considered as pathognomonic signs of allergy. The induction of allergic reactions in the tissue was inferred to be related to the amount of IgE passing through the vascular wall. AIMS: We attempted to clarify which compartment, the intravascular or extravascular, plays an important role in the regulation of the turnover of rat IgE. METHODS: The level of DNP-specific rat IgE in the serum was estimated by IgE-capture enzyme-linked immunosorbent assay, and the turnover of IgE was analyzed from its pharmacokinetic parameters. RESULTS: The transfer rate constants from the central to tissue compartment (Kct) were larger than those from the tissue to central compartment (Ktc) irrespective of the sensitized state. The value of the distribution volume of the tissue compartment (Vt) was larger than that of the distribution volume of the central compartment (Vc) irrespective of the sensitized state. CONCLUSIONS: These Findings suggest that the short half-life of rat IgE in the circulation could be attributable to the distribution of IgE from the intravascular to the extravascular compartment
Interpretation of microtremor 2D array data using Rayleigh and Love waves: the case study of Bevagna (central Italy)
In the last decades, geophysicists and seismologists have focused their attention on the inversion of
empirical surface-waves’ dispersion curves from microtremor measurements for estimating the Swaves
velocity structure at a site. This procedure allows a fast and convenient investigation without
strong active sources, which are difficult to deploy especially in urban areas.
In this study we report on a 2D seismic noise array experiment carried out at Bevagna (Central
Italy) near the station BVG of the Italian Accelerometric Network (RAN). The site was investigated
within the DPC-INGV S4 Project (2007-2009). The Rayleigh- and Love- waves dispersion
characteristics were estimated using different methods. The inversion of the dispersion curves was
then performed independently, obtaining two estimations for the S-waves velocity profiles. The
results of cross-hole logging near the seismic station are used for a comparison.
The shear waves velocity profiles estimated by microtremor analyses range up to 150m depth. The
two independent procedures provide consistent shear waves velocity profiles for the shallow part of
the model (20-30 m in depth) in agreement with the results of the cross-hole logging. Some
problems arise between 30 and 40 m in depth in the profile estimated by surface waves. In this
range cross-hole logging evidences an inversion of S-waves velocity. Although the cross-hole
logging stops at 40 m of depth, we are confident about the results provided by the Rayleigh-waves
analysis below 40-50 m. This case study suggests that greater efforts should be devoted to exploit
the potential of a coupled analysis of Rayleigh and Love waves from microtremor array
measurements
Human cachexia induces changes in mitochondria, autophagy and apoptosis in the skeletal muscle
Cachexia is a wasting syndrome characterized by the continuous loss of skeletal muscle mass due to imbalance between protein synthesis and degradation, which is related with poor prognosis and compromised quality of life. Dysfunctional mitochondria are associated with lower muscle strength and muscle atrophy in cancer patients, yet poorly described in human cachexia. We herein investigated mitochondrial morphology, autophagy and apoptosis in the skeletal muscle of patients with gastrointestinal cancer-associated cachexia (CC), as compared with a weight-stable cancer group (WSC). CC showed prominent weight loss and increased circulating levels of serum C-reactive protein, lower body mass index and decreased circulating hemoglobin, when compared to WSC. Electron microscopy analysis revealed an increase in intermyofibrillar mitochondrial area in CC, as compared to WSC. Relative gene expression of Fission 1, a protein related to mitochondrial fission, was increased in CC, as compared to WSC. LC3 II, autophagy-related (ATG) 5 and 7 essential proteins for autophagosome formation, presented higher content in the cachectic group. Protein levels of phosphorylated p53 (Ser46), activated caspase 8 (Asp384) and 9 (Asp315) were also increased in the skeletal muscle of CC. Overall, our results demonstrate that human cancer-associated cachexia leads to exacerbated muscle-stress response that may culminate in muscle loss, which is in part due to disruption of mitochondrial morphology, dysfunctional autophagy and increased apoptosis. To the best of our knowledge, this is the first report showing quantitative morphological alterations in skeletal muscle mitochondria in cachectic patients
Microtremor measurements interpretations at the BVG station of the Italian accelerometric network
In the last decades, researchers focused their attention on using inverse analysis of empirical surface‐waves
dispersion curves from microtremor measurements since it allows to keep the cost of investigation
relatively low and to avoid the use of active sources that might be prohibitive in urban areas.
In this study we reports the results and interpretations of the passive measurements carried out at a test
site in Bevagna (Italy) near the BVG station of the Italian Accelerometric Network (RAN) within the
framework of the DPC‐INGV S4 Project (2007‐2009). Using two independent approaches, Rayleigh and Love
wave dispersion characteristics were reproduced through two different inversion methods. At this site a
cross‐hole test made nearby the seismic station offers the opportunity to compare the subsoil velocity
profiles derived by seismic noise array data with independent geophysical information.
The results obtained from the separated Love waves and Rayleigh wave inversions analyses showed that
the two procedure provide consistent shear wave velocity profiles for the shallow part of the model in good
agreement with the results of the nearby cross‐hole test.
This case history shows the capabilities of surface wave analyses from passive source to adequately retrieve
the S‐wave subsoil structure and suggests that more efforts should be devoted in exploiting the potential of
coupled analysis of Rayleigh and Love waves from microtremor array measurements for site
characterization
Assessment of soil properties by organic matter and em-microorganism incorporation.
Summary: Properties of a claim loam soil, collected in Aranjuez (Madrid) and enriched with organic matter and microorganisms, were evaluated under controlled temperature and moisture conditions, over a period of three months. The following treatments were carried out: soil (control); soil + 50 t ha-1 of animal manure (E50); soil + 50 t ha-1 of animal manure + 30 L ha-1 of effective microorganisms (E50EM); soil + 30 t ha-1 of the combination of various green crop residues and weeds (RC30) and soil + 30 t ha-1 of the combination of various green crop residues and weeds + 30 L ha-1 of effective microorganisms (RC30EM). Soil samples were taken before and after incubation and their physical, chemical, and microbiological parameters analyzed. Significant increase was observed in the production of exopolysaccharides and basic phosphatase and esterase enzyme activities in the treatments E50EM and RC30EM, in correlation with the humification of organic matter, water retention at field capacity, and the cationic exchange capacity (CEC) of the same treatments. The conclusion was drawn that the incorporation of a mixture of effective microorganisms (EM) intensified the biological soil activity and improved physical and chemical soil properties, contributing to a quick humification of fresh organic matter. These findings were illustrated by the microbiological activities of exopolysaccharides and by alkaline phosphatase and esterase enzymes, which can be used as early and integrated soil health indicators. Resumo: As propriedades do solo foram avaliadas sob condições de temperatura e umidade controladas, após a incorporação da matéria orgânica e de microrganismos eficazes (EM), em um solo franco argiloso coletado sob cultivos protegidos em Aranjuéz (Madrid). Os seguintes tratamentos foram empregados: solo (controle); solo + 50 t ha-1 de esterco de animal (E50); E50 + 30 L ha-1 EM (E50EM); solo + 30 t ha-1 de restos de cultivos + plantas invasoras (RC30); RC30 + 30 L ha-1 EM (RC30EM). Amostras de solo foram retiradas após os tratamentos, antes e após a incubação e analisadas usando parâmetros físicos, químicos e microbiológicos. Os resultados mostraram um aumento significativo na produção de exopolissacarídeos, nas atividades enzimáticas de esterases e fosfatases alcalina principalmente, nos tratamentos E50EM e RC30EM, sendo diretamente correlacionadas com a humificação da matéria orgânica, com a capacidade de campo e com a capacidade de troca catiônica desses mesmos tratamentos. A partir desses resultados, pode se concluir que a qualidade do solo com a incorporação de EM potencializou a atividade biológica, contribuindo para uma mais rápida humificação da matéria orgânica fresca e melhorando a estrutura e fertilidade do solo, conforme análise das propriedades físicas e químicas, destacando-se os parâmetros microbiológicos como indicadores precoces de recuperação da qualidade do solo
Species Abundance Patterns in Complex Evolutionary Dynamics
An analytic theory of species abundance patterns (SAPs) in biological
networks is presented. The theory is based on multispecies replicator dynamics
equivalent to the Lotka-Volterra equation, with diverse interspecies
interactions. Various SAPs observed in nature are derived from a single
parameter. The abundance distribution is formed like a widely observed
left-skewed lognormal distribution. As the model has a general form, the result
can be applied to similar patterns in other complex biological networks, e.g.
gene expression.Comment: 4 pages, 3 figures. Physical Review Letters, in pres
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