157 research outputs found
Relative relocation of earthquakes without a predefined velocity model: an example from a peculiar seismic cluster on Katla volcano's south-flank (Iceland)
Relative relocation methods are commonly used to precisely relocate
earthquake clusters consisting of similar waveforms. Repeating waveforms are
often recorded at volcanoes, where, however, the crust structure is expected to
contain strong heterogeneities and therefore the 1D velocity model assumption
that is made in most location strategies is not likely to describe reality. A
peculiar cluster of repeating low-frequency seismic events was recorded on the
south flank of Katla volcano (Iceland) from 2011. As the hypocentres are
located at the rim of the glacier, the seismicity may be due to volcanic or
glacial processes. Information on the size and shape of the cluster may help
constraining the source process. The extreme similarity of waveforms points to
a very small spatial distribution of hypocentres. In order to extract
meaningful information about size and shape of the cluster, we minimize
uncertainty by optimizing the cross-correlation measurements and
relative-relocation process. With a synthetic test we determine the best
parameters for differential-time measurements and estimate their uncertainties,
specifically for each waveform. We design a relocation strategy to work without
a predefined velocity model, by formulating and inverting the problem to seek
changes in both location and slowness, thus accounting for azimuth, take-off
angles and velocity deviations from a 1D model. We solve the inversion
explicitly in order to propagate data errors through the calculation. With this
approach we are able to resolve a source volume few tens of meters wide on
horizontal directions and around 100 meters in depth. There is no suggestion
that the hypocentres lie on a single fault plane and the depth distribution
indicates that their source is unlikely to be related to glacial processes as
the ice thickness is not expected to exceed few tens of meters in the source
area
numerical analysis on the effect of focusing metasurfaces in energy harvesting applications
The aim of this thesis work is to describe Metasurfaces for Wireless Energy Harvesting (WEH) applications. The goal is to introduce newly conceptualized designs for focusing EM radiation into a predefined region with the aim of increasing the overall energy harvested by the system. The methodology behind the design of Metasurfaces for focusing applications will be described, with particular emphasis on PGMS (Phase-Shift Metasurfaces), together with their interaction with the freely propagating signals to obtain the desired ranging capability.
Two models have been proposed, operating at 2.45 GHz, for increasing the received power and therefore enhancing the overall efficiency of a WEH link. The structures, completely passive, present a symmetric topology composed by concentric rings: the first one (3 rings model) allows to precisely focus the power at 20 cm of distance with 6.6 dB gain, while the second one (2 rings model) focuses the power at 2.5 cm with a gain 3 dB with less precision but proposing a compact design. The results have been obtained considering a link of 1 m where the transmitter and receiver are planar patches and it has been demonstrated how the presence of the metasurfaces increases the received power level, highlighting them as one of the most promising solutions for WEH applications
Chest wall reconstruction with implantable cross-linked porcine dermal collagen matrix: Evaluation of clinical outcomes
Objectives: The aim of the study is to evaluate clinical applications, safety, and effectiveness of a porcine-derived acellular cross-linked dermal matrix biological mesh in chest wall reconstruction. Methods: We retrospectively analyzed a prospective multicenter database of chest wall reconstructions using a biological mesh in adult patients undergoing operation between October 2013 and December 2020. We evaluated preoperative data, type of resection and reconstruction, hospitalization, 30-day morbidity and mortality, and overall survival. Results: A total of 105 patients (36 women [34.2%]; mean age, 57.0 +/- 16.1 years; range, 18-90 years) were included, they have admitted for: primary chest wall tumor (n = 52; 49.5%), secondary chest wall tumor (n = 29; 27.6%), lung hernia (n = 12; 11.4%), trauma (n =10; 9.6%), and infections (n = 2; 1.9%). The surgical sites were preoperatively defined as at high risk of infection in 28 patients (26.7%) or as infected in 16 (15.2%) patients. Thirty-days morbidity was 30.5% (n = 32 patients); 14 patients (13.3%) had postoperative complications directly related to chest wall surgical resection and/or reconstruction. We experienced no 30-day mortality; 1-year and 2-year mortality was 8.4% and 16.8%, respectively. Conclusions: Biological mesh represents a valuable option in chest wall reconstruction even when surgical sites are infected or at high-risk of infections. This mesh shows low early and late postoperative complication rates and excellent long-term stability
The effect of three large Mw¿7.3 subduction earth-quakes (August-November 2012) on volcanic unrest in Central America
¿Was the volcanic eruption triggered by the earthquake?¿ The answer to this question usually
is ¿maybe¿ or ¿a coincidence¿. A region like Central America, is an adequate area to find hints to
answer this question because have the necessary ingredients: the frequent occurrence of large
earthquakes (M5+) and dozens of active volcanoes. This research focuses
on whether the
uncommon occurrence of three large earthquakes in the subduction zone of Central America,
within a time span of ten weeks in 2012, promoted enhanced volcanic activity. The time window
analyzed is from 2000 to 2019, which includes a total of 50 volcanic eruptions with a VEI¿2.
Before the 2012 earthquakes, 22 eruptions occurred.
The Monte Carlo statistical simulation
method allowed to demonstrate that this increase in the number of volcanic eruptions after the
three large earthquakes of 2012 it is not a temporal coincidence. We analyzed the characteristics
of each earthquake and described how they could disturb the volcanic systems. Although Central
America hosts 24 volcanoes with historical eruptions, only 11 of them erupted after the 2012
earthquakes. Why did only these volcanoes erupt? To answer this question, we calculated the
dynamic and static stress in each volcano and the level of volcanic unrest (the change in volcanic
activity beyond background behavior to worrisome levels) prior to the earthquakes. We found
that volcanoes in a unrest stage before the earthquakes but, without experiencing explosive
eruptions before, erupted after receiving the seismic shocks. This fact suggests that the
earthquakes by themselves did not transfer enough energy to generate the volcanic eruptions
when volcanoes were not ready to erupt. However, earthquakes could promote volcanic
eruptions when volcanoes were already at unrest. This research offers a tool for forecasting
volcanic activity when a large earthquake hits a region, if the volcanic activity
is previously
monitored
ALK rearrangement in a large series of consecutive non-small cell lung cancers: Comparison between a new immunohistochemical approach and fluorescence in situ hybridization for the screening of patients eligible for crizotinib treatment
Context. - Echinoderm microtubule associated protein-like 4-anaplastic lymphoma receptor tyrosine kinase (EML4-ALK) translocation has been described in a subset of patients with non-small cell lung cancer (NSCLC) and has been shown to have oncogenic activity. Fluorescence in situ hybridization (FISH) is used to detect ALK-positive NSCLC, but it is expensive, time-consuming, and difficult for routine application. Objective. - To evaluate the potential role of immunohistochemistry (IHC) as a screening tool to identify candidate cases for FISH analysis and for ALK inhibitor therapy in NSCLC. Design. - We performed FISH and IHC for ALK and mutational analysis for epidermal growth factor receptor (EGFR) and KRAS in 523 NSCLC specimens. We conducted IHC analysis with the monoclonal antibody D5F3 (Ventana Medical Systems, Tucson, Arizona) and a highly sensitive detection system. We also performed a MassARRAY-based analysis (Sequenom, San Diego, California) in a small subset of 11 samples to detect EML4-ALK rearrangement. Results. - Of the 523 NSCLC specimens, 20 (3.8%) were positive for ALK rearrangement by FISH analysis. EGFR and KRAS mutations were identified in 70 (13.4%) and 124 (23.7%) of the 523 tumor samples, respectively. ALK rearrangement and EGFR and KRAS mutations were mutually exclusive. Of 523 tumor samples analyzed, 18 (3.4%) were ALK+ by IHC, 18 samples (3.4%) had concordant IHC and FISH results, and 2 ALK+ cases (0.3%) by FISH failed to show ALK protein expression. In the 2 discrepant cases, we did not detect any mass peaks for the EML4-ALK variants by MassARRAY. Conclusions. - Our results show that IHC may be a useful technique for selecting NSCLC cases to undergo ALK FISH analysis
FIRST RECORD OF RICANIA SPECULUM(WALKER, 1851) (HEMIPTERA RICANIIDAE)FROM VENETO, PIEDMONT AND LATIUM REGIONS AND NEW HOST PLANTS
The distribution of Ricania speculum(Walker, 1851) (Hemiptera Fulgoromorpha Ricaniidae) in Italy was updatedand the species was recorded for the first time in Veneto (2017), Piedmont (2018) and Latium (2018) regions. Theoccurrence of this species in Sardinia, previously recorded, is here excluded. Moreover, 33 new host plants belonging to 29families resulted to be attacked by this alien invasive species confirming its outstanding polyphagy
Increment in the volcanic unrest and number of eruptions after the 2012 large earthquakes sequence in Central America.
Understanding the relationship cause/effect between tectonic earthquakes and volcanic eruptions is a striking topic in Earth Sciences. Volcanoes erupt with variable reaction times as a consequence of the impact of seismic waves (i.e. dynamic stress) and changes in the stress field (i.e. static stress).In2012, three large(Mw≥7.3)subductionearthquakes struck Central Americawithin a period of 10 weeks;subsequently, some volcanoesin the regionerupted a few days after, whileotherstook months or even years to erupt. Here, we show thatthese threeearthquakes contributed to the increase in the number of volcanic eruptionsduring the 7 years that followed these seismic events. We found that onlythosevolcanoes that were already in a critical state ofunrest eventually erupted, which indicates that the earthquakes only prompted the eruptions. Therefore, we recommend the permanent monitoring of active volcanoes toreveal which are more susceptible to culminate into eruption in the aftermath of the next large-magnitude earthquake hits a region.Funding was provided by Japan International Cooperation Agency (JICA) and Istitute Nazionale di Geofisica e Vulcanologia (INGV).Peer reviewe
Author Correction: Increment in the volcanic unrest and number of eruptions after the 2012 large earthquakes sequence in Central America
Correction to: Scientific Reports https://doi.org/10.1038/s41598-021-01725-1, published online 17 November 2021.The original version of this Article contained a repeated error in the Introduction, in Figure 1 and its accompanying legend, in the Results section under the subheading ‘Stress changes caused by the earthquakes’, in the Discussion and conclusions section under the subheading ‘Volcanic eruptions long after the earthquakes’, and in the Supplementary Information file, where the earthquake that occurred on November 7, 2012 was incorrectly mentioned as having occurred on November 11, 2012. The original Fig. 1 and accompanying legend appear below. The original Article and the Supplementary Information file that accompanies the original Article have been corrected.Peer reviewe
Pathological and clinical features of multiple cancers and lung adenocarcinoma: a multicentre study
OBJECTIVES: Lung cancer is increasingly diagnosed as a second cancer. Our goal was to analyse the characteristics and outcomes of early-stage resected lung adenocarcinomas in patients with previous cancers (PC) and correlations with adenocarcinoma subtypes.METHODS: We retrospectively reviewed data of patients radically operated on for stage I-II lung adenocarcinoma in 9 thoracic surgery departments between 2014 and 2017. Overall survival (OS) and time to disease relapse were evaluated between subgroups.RESULTS: We included 700 consecutive patients. PC were present in 260 (37.1%). Breast adenocarcinoma, lung cancer and prostate cancer were the most frequent (21.5%, 11.5% and 11.2%, respectively). No significant differences in OS were observed between the PC and non-PC groups (P = 0.378), with 31 and 75 deaths, respectively. Patients with PC had smaller tumours and were more likely to receive sublobar resection and to be operated on with a minimally invasive approach. Previous gastric cancer (P = 0.042) and synchronous PC (when diagnosed up to 6 months before lung adenocarcinoma; P = 0.044) were related, with a worse OS. Colon and breast adenocarcinomas and melanomas were significantly related to a lower incidence of high grade (solid or micropapillary, P = 0.0039, P = 0.005 and P = 0.028 respectively), whereas patients affected by a previous lymphoma had a higher incidence of a micropapillary pattern (P = 0.008).CONCLUSIONS: In patients with PC, we found smaller tumours more frequently treated with minimally invasive techniques and sublobar resection, probably due to a more careful follow-up. The impact on survival is not uniform and predictable; however, breast and colon cancers and melanoma showed a lower incidence of solid or micropapillary patterns whereas patients with lymphomas had a higher incidence of a micropapillary pattern
Impact of High‑Grade Patterns in Early‑Stage Lung Adenocarcinoma: A Multicentric Analysis
Objective The presence of micropapillary and solid adenocarcinoma patterns leads to a worse survival and a signifcantly higher tendency to recur. This study aims to assess the impact of pT descriptor combined with the presence of high-grade components on long-term outcomes in early-stage lung adenocarcinomas.
Methods We retrospectively collected data of consecutive resected pT1-T3N0 lung adenocarcinoma from nine European Thoracic Centers. All patients who underwent a radical resection with lymph-node dissection between 2014 and 2017 were included. Diferences in Overall Survival (OS) and Disease-Free Survival (DFS) and possible prognostic factors associated with outcomes were evaluated also after performing a propensity score matching to compare tumors containing non-highgrade and high-grade patterns.
Results Among 607 patients, the majority were male and received a lobectomy. At least one high-grade histological pattern was seen in 230 cases (37.9%), of which 169 solid and 75 micropapillary. T1a-b-c without high-grade pattern had a signifcant better prognosis compared to T1a-b-c with high-grade pattern (p=0.020), but the latter had similar OS compared to T2a (p=0.277). Concurrently, T1a-b-c without micropapillary or solid patterns had a signifcantly better DFS compared to
those with high-grade patterns (p=0.034), and it was similar to T2a (p=0.839). Multivariable analysis confrms the role of T descriptor according to high-grade pattern both for OS (p=0.024; HR 1.285 95% CI 1.033–1.599) and DFS (p=0.003; HR 1.196, 95% CI 1.054–1.344, respectively). These results were confrmed after the propensity score matching analysis.
Conclusions pT1 lung adenocarcinomas with a high-grade component have similar prognosis of pT2a tumors
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