780 research outputs found
Disturbances in groundwater chemical parameters related to seismic and volcanic activity in Kamchatka (Russia)
International audienceStarting from 1992 geochemical data are being collected with a mean sampling frequency of three days in the form of the pH value and of the most common ions and gases in the groundwater in one deep well located in Petropavlovsk, the capital city of Kamchatka (Russia). On 1 January 1996 a strong eruption started from the Karymsky volcano, that is located about 100km far from the well, in the north-northeastern direction. At the same time, a large earthquake (M=6.9) occurred in the Karymsky area. On 5 December 1997 a very large earthquake (M=7.7) occurred offshore, at a distance of 350km from the well and towards the same direction. The analysis of the geochemical data shows clear variations in the raw temporal trends on both cases. For the first event, a clear premonitory phase appeared; for the second one, some pre-seismic variations could be revealed but permanent modifications of the chemistry of the water subsequent to the earthquake are very clear. In both cases the feature of the geochemical variations is consistent with an afflux of new water in the aquifer connected with the well and with an escape of the Carbon dioxide gas from the ground in different directions. A schematic model able to justify such a phenomenology and the connections of the geochemical variations with the previous tectonic activities is proposed
Retrospective analysis for detecting seismic precursors in groundwater argon content
We examined the groundwater Argon content data sampled from 1988 to 2001 at two wells in Kamchatka (Russia) and anomalous increases appeared clearly during June-July 1996. On 21 June, a shallow (1km) earthquake with <i>M</i>=7.1 occurred at a distance less than 250km from the wells and so the previous increases could be related to this earthquake and, in particular, could be considered premonitory anomalies. In order to support this raw interpretation, we analysed the data collected in details. At first we smoothed out the high frequency fluctuations arising from the errors in a single measurement. Next we considered the known external effects on the water of a well that are the slow tectonic re-adjustment processes, the meteorology and the gravity tides and we separated these effects applying band-pass filters to the Argon content raw trends. Then we identified the largest fluctuations in these trends applying the 3 σ criterion and we found three anomalies in a case and two anomalies in other case. Comparing the time occurrence of the anomalies at the two wells we found out that a coincidence exists only in the case of the premonitory anomalies we are studying. The simultaneous appearance of well definite anomalies in the residual trends of the same parameter at two different sites supports their meaning and the possibility that they are related to some large scale effect, as the occurrence of a strong earthquake. But, other earthquakes similar to the June 1996 event took place during the Argon content measurements time and no anomaly appeared in this content. In the past, some of the authors of this paper studied the Helium content data collected in three natural springs of the Caucasus during seven years. A very similar result, that is the simultaneous appearance of clear premonitory anomalies only on the occasion of a strong (<i>M</i>=7.0) but shallow (2–4km) earthquake, was obtained. The correspondence with the case of the Caucasus validates the interpretation of the Kamchatkian anomalies as precursors
Effectiveness of dolutegravir-based regimens as either first-line or switch antiretroviral therapy: data from the Icona cohort
Introduction: Concerns about dolutegravir (DTG) tolerability in the real-life setting have recently arisen. We aimed to estimate the risk of treatment discontinuation and virological failure of DTG-based regimens from a large cohort of HIV-infected individuals. Methods: We performed a multicentre, observational study including all antiretroviral therapy (ART)-naïve and virologically suppressed treatment-experienced (TE) patients from the Icona (Italian Cohort Naïve Antiretrovirals) cohort who started, for the first time, a DTG-based regimen from January 2015 to December 2017. We estimated the cumulative risk of DTG discontinuation regardless of the reason and for toxicity, and of virological failure using Kaplan–Meier curves. We used Cox regression model to investigate predictors of DTG discontinuation. Results: About 1679 individuals (932 ART-naïve, 747 TE) were included. The one- and two-year probabilities (95% CI) of DTG discontinuation were 6.7% (4.9 to 8.4) and 11.5% (8.7 to 14.3) for ART-naïve and 6.6% (4.6 to 8.6) and 7.6% (5.4 to 9.8) for TE subjects. In both ART-naïve and TE patients, discontinuations of DTG were mainly driven by toxicity with an estimated risk (95% CI) of 4.0% (2.6 to 5.4) and 2.5% (1.3 to 3.6) by one year and 5.6% (3.8 to 7.5) and 4.0% (2.4 to 5.6) by two years respectively. Neuropsychiatric events were the main reason for stopping DTG in both ART-naïve (2.1%) and TE (1.7%) patients. In ART-naïve, a concomitant AIDS diagnosis predicted the risk of discontinuing DTG for any reason (adjusted relative hazard (aRH) = 3.38, p = 0.001), whereas starting DTG in combination with abacavir (ABC) was associated with a higher risk of discontinuing because of toxicity (aRH = 3.30, p = 0.009). TE patients starting a DTG-based dual therapy compared to a triple therapy had a lower risk of discontinuation for any reason (adjusted hazard ratio (aHR) = 2.50, p = 0.037 for ABC-based triple-therapies, aHR = 3.56, p = 0.012 for tenofovir-based) and for toxicity (aHR = 5.26, p = 0.030 for ABC-based, aHR = 6.60, p = 0.024 for tenofovir-based). The one- and two-year probabilities (95% CI) of virological failure were 1.2% (0.3 to 2.0) and 4.6% (2.7 to 6.5) in the ART naïve group and 2.2% (1.0 to 3.3) and 2.9% (1.5 to 4.3) in the TE group. Conclusions: In this large cohort, DTG showed excellent efficacy and optimal tolerability both as first-line and switching ART. The low risk of treatment-limiting toxicities in ART-naïve as well as in treated individuals reassures on the use of DTG in everyday clinical practice
Photometric redshifts and clustering of emission line galaxies selected jointly by DES and eBOSS
We present the results of the first test plates of the extended Baryon
Oscillation Spectroscopic Survey. This paper focuses on the emission line
galaxies (ELG) population targetted from the Dark Energy Survey (DES)
photometry. We analyse the success rate, efficiency, redshift distribution, and
clustering properties of the targets. From the 9000 spectroscopic redshifts
targetted, 4600 have been selected from the DES photometry. The total success
rate for redshifts between 0.6 and 1.2 is 71\% and 68\% respectively for a
bright and faint, on average more distant, samples including redshifts measured
from a single strong emission line. We find a mean redshift of 0.8 and 0.87,
with 15 and 13\% of unknown redshifts respectively for the bright and faint
samples. In the redshift range 0.6<z<1.2, for the most secure spectroscopic
redshifts, the mean redshift for the bright and faint sample is 0.85 and 0.9
respectively. Star contamination is lower than 2\%. We measure a galaxy bias
averaged on scales of 1 and 10~Mpc/h of 1.72 \pm 0.1 for the bright sample and
of 1.78 \pm 0.12 for the faint sample. The error on the galaxy bias have been
obtained propagating the errors in the correlation function to the fitted
parameters. This redshift evolution for the galaxy bias is in agreement with
theoretical expectations for a galaxy population with MB-5\log h < -21.0. We
note that biasing is derived from the galaxy clustering relative to a model for
the mass fluctuations. We investigate the quality of the DES photometric
redshifts and find that the outlier fraction can be reduced using a comparison
between template fitting and neural network, or using a random forest
algorithm
Characterization of a new trabectedin-resistant myxoid liposarcoma cell line that shows collateral sensitivity to methylating agents
Myxoid Liposarcomas (MLS), characterized by the expression of FUS-CHOP fusion gene are clinically very sensitive to the DNA binding antitumor agent, trabectedin. However, resistance eventually occurs, preventing disease eradication. To investigate the mechanisms of resistance, a trabectedin resistant cell line, 402-91/ET, was developed. The resistance to trabectedin was not related to the expression of MDR related proteins, uptake/efflux of trabectedin or GSH levels that were similar in parental and resistant cells. The 402-91/ET cells were hypersensitive to UV light because of a nucleotide excision repair defect: XPG complementation decreased sensitivity to UV rays, but only partially to trabectedin. 402-91/ET cells showed collateral sensitivity to temozolomide due to the lack of O(6) -methylguanine-DNA-methyltransferase (MGMT) activity, related to the hypermethylation of MGMT promoter. In 402-91 cells chromatin immunoprecipitation (ChIP) assays showed that FUS-CHOP was bound to the PTX3 and FN1 gene promoters, as previously described, and trabectedin caused FUS-CHOP detachment from DNA. Here we report that, in contrast, in 402-91/ET cells, FUS-CHOP was not bound to these promoters. Differences in the modulation of transcription of genes involved in different pathways including signal transduction, apoptosis and stress response between the two cell lines were found. Trabectedin activates the transcription of genes involved in the adipogenic-program such as c/EBPα and β, in 402-91 but not in 402-91/ET cell lines. The collateral sensitivity of 402-91/ET to temozolomide provides the rationale to investigate the potential use of methylating agents in MLS patients resistant to trabectedin
Monitoring the volatilome of kefir and kefir-like cereal-based beverages during fermentation by PTR-Tof-MS
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