1,494 research outputs found
Effects of Surface Geology on Seismic Ground Motion Deduced from Ambient-Noise Measurements in the Town of Avellino, Irpinia Region (Italy)
The effects of surface geology on ground motion
provide an important tool in seismic hazard studies. It is well
known that the presence of soft sediments can cause amplification
of the ground motion at the surface, particularly when there is a
sharp impedance contrast at shallow depth. The town of Avellino is
located in an area characterised by high seismicity in Italy, about
30 km from the epicentre of the 23 November 1980, Irpinia
earthquake (M = 6.9). No earthquake recordings are available in
the area. The local geology is characterised by strong heterogeneity,
with impedance contrasts at depth. We present the results
from seismic noise measurements carried out in the urban area of
Avellino to evaluate the effects of local geology on the seismic
ground motion. We computed the horizontal-to-vertical (H/V)
noise spectral ratios at 16 selected sites in this urban area for which
drilling data are available within the first 40 m of depth. A Rayleigh
wave inversion technique using the peak frequencies of the
noise H/V spectral ratios is then presented for estimating Vs
models, assuming that the thicknesses of the shallow soil layers are
known. The results show a good correspondence between experimental
and theoretical peak frequencies, which are interpreted in
terms of sediment resonance. For one site, which is characterised
by a broad peak in the horizontal-to-vertical spectral-ratio curve,
simple one-dimensional modelling is not representative of the
resonance effects. Consistent variations in peak amplitudes are seen
among the sites. A site classification based on shear-wave velocity
characteristics, in terms of Vs30, cannot explain these data. The
differences observed are better correlated to the impedance contrast
between the sediments and basement. A more detailed investigation
of the physical parameters of the subsoil structure, together with
earthquake data, are desirable for future research, to confirm these
data in terms of site response
Treatment responses to antiangiogenetic therapy and chemotherapy in nonsecreting paraganglioma (PGL4) of urinary bladder with SDHB mutation: a case report
Paraganglioma (PGL) is a rare neuroendocrine tumor. Currently, the malignancy is defined as the presence of metastatic spread at presentation or during follow-up. Several gene mutations are listed in the pathogenesis of PGL, among which succinate dehydrogenase (SDHX), particularly the SDHB isoform, is the main gene involved in malignancy. A 55-year-old male without evidence of catecholamine secretion had surgery for PGL of the urinary bladder. After 1 year, he showed a relapse of disease and demonstrated malignant PGL without evidence of catecholamine secretion with a germline heterozygous mutation of succinate dehydrogenase B (SDHB). After failure of a second surgery for relapse, he started medical treatment with sunitinib daily but discontinued due to serious side effects. Cyclophosphamide, vincristine, and dacarbazine (CVD) chemotherapeutic regimen stopped the disease progression for 7 months.
Conclusion: Malignant PGL is a very rare tumor, and SDHB mutations must be always considered in molecular diagnosis because they represent a critical event in the progression of the oncological disease. Currently, there are few therapeutic protocols, and it is often difficult, as this case demonstrates, to decide on a treatment option according to a reasoned set of choices.
Abbreviations: CVD = cyclophosphamide, vincristine and dacarbazine, HIF-1a = hypoxia inducible factor 1 alpha, PGL = paraganglioma, SDH = succinate dehydrogenase, VEGF = vasoendothelial growth factor
Can remote STI/HIV testing and eClinical Care be compatible with robust public health surveillance?
In this paper we outline the current data capture systems for human immunodeficiency virus (HIV) and sexually transmitted infection (STI) surveillance used by Public Health England (PHE), and how these will be affected by the introduction of novel testing platforms and changing patient pathways. We outline the Chlamydia Online Clinical Care Pathway (COCCP), developed as part of the Electronic Self-Testing for Sexually Transmitted Infections (eSTI(2)) Consortium, which ensures that surveillance data continue to be routinely collected and transmitted to PHE. We conclude that both novel diagnostic testing platforms and established data capture systems must be adaptable to ensure continued robust public health surveillance
A 31T split-pair pulsed magnet for single crystal x-ray diffraction at low temperature
We have developed a pulsed magnet system with panoramic access for
synchrotron x-ray diffraction in magnetic fields up to 31T and at low
temperature down to 1.5 K. The apparatus consists of a split-pair magnet, a
liquid nitrogen bath to cool the pulsed coil, and a helium cryostat allowing
sample temperatures from 1.5 up to 250 K. Using a 1.15MJ mobile generator,
magnetic field pulses of 60 ms length were generated in the magnet, with a rise
time of 16.5 ms and a repetition rate of 2 pulses/hour at 31 T. The setup was
validated for single crystal diffraction on the ESRF beamline ID06
Heat shock induced changes of adipokines gene expression in 3T3-L1 adipocytes
To study the effects of heat shock on adipokines gene expression 3T3-L1 adipocytes were used. Heat shock differently affected gene expression of leptin, adiponectin and acylation stimulating protein (ASP): exposure of cells to temperature higher than 39°C caused upregulation of leptin and downregulation of adiponectin and ASP genes. The present study provides the first evidence about the effects of heat shock on adipokines gene expression. Changes in gene expression of the three adipokines may help to explain the alteration of lipid metabolism and liver functionality occurring in animals exposed to hot conditions
Application of the spac method to ambient noise recorded in the vesuvius area (italy)
Noise measurements were recorded using a dense short-period seismic
array in Terzigno (Naples), a town that is located about 6 km from the Vesuvius crater. The
aim of this study was to calculate a surface velocity model of the area under investigation
through the application of the Spatial Autocorrelation (SPAC) method, with the hypotheses
that ambient noise is stationary both in time and space, and that it is composed of surface
dispersive waves. The correct knowledge of the surface structure is an important goal in
site-effects studies. Correlation coefficients were calculated as functions of the azimuth on
noise recorded at pairs of equally spaced stations in the frequency range of 1-8 Hz. Then,
the spatial average correlation coefficients were compared to estimates over long-term
recordings. The results appear to validate the hypothesis that ambient noise can be
considered as a stochastic process. The correlation-frequency curves have been fitted to
Bessel functions, from which the Rayleigh wave dispersion curve has been calculated. A
velocity model has been derived from the dispersion curve using both trial and error and a
standard inversion procedure. The results are consistent with those obtained from array
measurements in the area in other studies (Scarpa et al., 2003)
energy consumption of a last generation full hybrid vehicle compared with a conventional vehicle in real drive conditions
Abstract Hybrid vehicles are one of the most important choices to improve efficiency and reduce CO2 production of vehicles. Benefits in using hybrid powertrains are generally found in urban environment where lower average speeds, higher accelerations make the internal combustion engine run at lower efficiency points. The originality of the present paper consists in the data elaboration and analysis collected in a measurement campaign on road in real driving conditions, on an ad hoc path planned according to the average national daily mileage in metropolitan urban context, which thus acquires a significance generalizable in that specific context, which led to the consumption quantification and an analysis of the main factors that determine the reduction in consumption of full-hybrid vs conventional vehicles. Another important and original aspect of this paper is the analysis of the operating times in ZEV mode of hybrid vehicles, which shows how this solution leads to a significant reduction of pollutant emissions in urban contest. An on-road experimental campaign has been done by comparing two different versions of the same model (Toyota Yaris Hybrid and a conventional one, Toyota Yaris 1.5 gasoline) and a hybrid vehicle with different characteristics (the hybrid born - Toyota Prius), like size, traction battery capacity, generator/motor electric power. Thirty drivers on a fixed path have done this experimental campaign and in this paper, the results are reported. The results show that a strong influence on consumption is due not only to the type of vehicle, but also to driving style and speed. The comparison between the two versions of Yaris, shows a strong reduction in consumption using hybrid vehicle for low and medium speeds (for 20 km/h about 50%), such benefit decreases with the increasing speed and for values higher than 90 km/h both the vehicles have the same consumption. The reduced consumption of the hybrid vehicle at low speeds is due, on the one hand, to the greater efficiency of the hybrid vehicle engine compared to the conventional one and on the other hand to the high functioning in ZEV mode, with the engine off, (63% of time) thanks to the use of the electric motor. The comparison between the two hybrid vehicles with different characteristics (YarisHy and Prius) shows that the consumption trend vs. speeds is similar but the Prius has lower consumption due above all to the high efficiency of the braking energy recovery system, despite the greatest mass. This lead then to significant consumption reduction, but also lower emissions in places where such parameters have an important role: the urban environment
Molecular targets of developmental exposure to bisphenol A in diabesity: a focus on endoderm-derived organs
Several studies associate foetal human exposure to bisphenol A (BPA) to metabolic/endocrine diseases, mainly diabesity. They describe the role of BPA in the disruption of pancreatic beta cell, adipocyte and hepatocyte functions. Indeed, the complexity of the diabesity phenotype is due to the involvement of different endoderm-derived organs, all targets of BPA. Here, we analyse this point delineating a picture of different mechanisms of BPA toxicity in endoderm-derived organs leading to diabesity. Moving from epidemiological data, we summarize the in vivo experimental data of the BPA effects on endoderm-derived organs (thyroid, pancreas, liver, gut, prostate and lung) after prenatal exposure. Mainly, we gather molecular data evidencing harmful effects at low-dose exposure, pointing to the risk to human health. Although the fragmentation of molecular data does not allow a clear conclusion to be drawn, the present work indicates that the developmental exposure to BPA represents a risk for endoderm-derived organs development as it deregulates the gene expression from the earliest developmental stages. A more systematic analysis of BPA impact on the transcriptomes of endoderm-derived organs is still missing. Here, we suggest in vitro toxicogenomics approaches as a tool for the identification of common mechanisms of BPA toxicity leading to the diabesity in organs having the same developmental origin
Shubnikov-de Haas oscillations in YBa_2Cu_4O_8
We report the observation of Shubnikov-de Haas oscillations in the underdoped
cuprate superconductor YBaCuO (Y124). For field aligned along the
c-axis, the frequency of the oscillations is T, which corresponds
to % of the total area of the first Brillouin zone. The effective
mass of the quasiparticles on this orbit is measured to be times
the free electron mass. Both the frequency and mass are comparable to those
recently observed for ortho-II YBaCuO (Y123-II). We show that
although small Fermi surface pockets may be expected from band structure
calculations in Y123-II, no such pockets are predicted for Y124. Our results
therefore imply that these small pockets are a generic feature of the copper
oxide plane in underdoped cuprates.Comment: v2: Version of paper accepted for publication in Physical Review
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