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Fast and reliable characterization of earthquakes can provide vital information to the population, even reducing the effects of strong shaking produced by them. In this study, we explore the minimum time required to estimate the magnitude for subduction earthquakes. Using traditional Pwave earthquake early warning parameters and considering a progressively increasing time window, we are able to estimate magnitude for subduction earthquakes ~30 s from the origin time (with an average residual of 0.01 ± 0.28). However, estimations for larger events (Mw ≥ 7.5) present larger errors (average residual of −0.70 ± 0.30). We complement our data with Global Navigational Satellite System observations for these events, enabling magnitude estimations ~70 s from the origin time (average residual of −0.42 ± 0.41). We propose that rapid estimations of magnitude should consider, initially, Pwaves in a progressively increasing time window, and complemented with GNSS data, for large events. Fast and reliable magnitude estimation of earthquakes enables the preparation of the public to reduce its impact. Here we test known methods to rapidly estimate the magnitude of subduction earthquakes. We found encouraging results, taking a few tens of seconds to provide reliable values. However, results for larger events tend to underestimate the real magnitude. Hence, we propose the combination with other sources of information, such as Global Positioning System, that are able to resolve these larger events. We calibrate coefficients from earthquake early warning methodologies to do a fast estimation of magnitude for subduction earthquakesThese methodologies are able to robustly estimate the magnitude for small‐to‐moderate events (Mw ≤ 7.0) ~30 from origin timeLarge events (Mw ≥ 7.5) required data from GNSS to perform the magnitude estimation ~70 s from origin time

Fundamental processes of the seismic cycle in subduction zones, including those controlling the recurrence and size of great earthquakes, are still poorly understood. Here, by studying the 2016 earthquake in southern Chile—the first large event within the rupture zone of the 1960 earthquake (moment magnitude (Mw) = 9.5)—we show that the frictional zonation of the plate interface fault at depth mechanically controls the timing of more frequent, moderate-size deep events (Mw< 8) and less frequent, tsunamigenic great shallow earthquakes (Mw> 8.5). We model the evolution of stress build-up for a seismogenic zone with heterogeneous friction to examine the link between the 2016 and 1960 earthquakes. Our results suggest that the deeper segments of the seismogenic megathrust are weaker and interseismically loaded by a more strongly coupled, shallower asperity. Deeper segments fail earlier (~60 yr recurrence), producing moderate-size events that precede the failure of the shallower region, which fails in a great earthquake (recurrence >110 yr). We interpret the contrasting frictional strength and lag time between deeper and shallower earthquakes to be controlled by variations in pore fluid pressure. Our integrated analysis strengthens understanding of the mechanics and timing of great megathrust earthquakes, and therefore could aid in the seismic hazard assessment of other subduction zones. The recurrence time of megathrust earthquakes in Chile may be controlled by frictional contrasts at depth, according to analyses of stress build-up and release related to the December 2016 southern Chile earthquake.

On 25 December 2016, the Mw7.6 Chiloé earthquake broke a plate boundary asperity in south central Chile near the center of the rupture zone of the Mw9.5 Valdivia earthquake of 1960. To gain insight on decadal‐scale deformation trends and their relation with the Chiloé earthquake, we combine geodetic, teleseismic, and regional seismological data. GPS velocities increased at continental scale after the 2010 Maule earthquake, probably due to a readjustment in the mantle flow and an apparently abrupt end of the viscoelastic mantle relaxation following the 1960 Valdivia earthquake. It also produced an increase in the degree of plate locking. The Chiloé earthquake occurred within the region of increased locking, breaking a circular patch of ~15 km radius at ~30 km depth, located near the bottom of the seismogenic zone. We propose that the Chiloé earthquake is a first sign of the seismic reawakening of the Valdivia segment, in response to the interaction between postseismic viscoelastic relaxation and changes of interseismic locking between Nazca and South America. The 2016 Chiloe earthquake is a sign of the seismic reactivation of the south central Chile megathrust after the Mw9.5 earthquake of 1960South central Chile has been affected by postseismic viscoelastic relaxation and superinterseismic locking after the 2010 Maule earthquakeThe Chiloe earthquake broke an ~15 km radius area at ~30 km depth, near the bottom of the seismogenic zone

The present study reports the occurrence of the genus Belonolaimus in the state of Sinaloa, Mexico, associated with native plants (i.e., Ziziphus amole and Stenocereus alamosensis) in a natural coastal ecosystem. Both morphological and molecular approaches were employed to characterize the Sinaloa population. Notwithstanding of some morphological and morphometric variation between Belonolaimus from Sinaloa and other valid species, the characterization indicates that this population might belong to the Belonolaimus longicaudatus species complex. Molecular analyses based on the 28S gene and ITS1-5.8S-ITS2 regions of the ribosomal RNA (rRNA) identified four major clades within Belonolaimus; however, none of the species including B. longicaudatus, B. gracilis, and B. euthychilus were supported as monophyletic; yet monophyly is argued to be a basic requirement of species status. Sequence divergence among different Belonolaimus populations and species varied according to the rRNA dataset (i.e., ITS1-5.8S-ITS2 . 28S . 18S) used, thus showing the importance of using genes with different rates of evolution to estimate species relationships. The fact that Belonolaimus has not been found in other cultivated (including on suitable hosts) areas in Sinaloa and that this population is relatively distant from the common B. longicaudatus groups (i.e., clades A and B) suggests that its appearance was not due to a recent introduction associated with the local agriculture.

Asymmetric telechelic α-hydroxyl-ω-(carboxylic acid) poly(ε-caprolactone) (HA-PCL) and α-hydroxyl-ω-(carboxylic acid) poly(δ-valerolactone) (HA-PVL) were synthesized by ring-opening polymerization of ε-caprolactone (CL) and δ-valerolactone (VL), respectively. HA-PCL oligomers were obtained at 150 °C in 2 h using ammonium decamolybdate (NH4)8[Mo10O34] as catalyst and water as initiator. A control of the number-average molecular weight (measured by NMR) can be achieved in the range between 212 and 2198 Da, based on the initial monomer/initiator ratio. Number-average molecular weight (Mn) shows a linear dependence with CL/H2O ratio in this range. The nature of hydroxyl and carboxylic acid end groups of HA-PCL and HA-PVL was studied by MALDI-TOF and ¹H and ¹³C NMR. Changes in the chemical shifts observed in the NMR spectra as a function of molecular weight were explained in terms of hydrophobic interactions. Formation of macrocyclic species was studied by MALDI-TOF. It was found that macrocyclic species are favored at longer reaction times. Insertion of alcohols and polycondensation reactions occurring after complete monomer conversion were also studied. Alcohol insertion for this system depends on the nature of alcohol. Polycondensation reactions vary with reaction times and affect the polymer molecular weight in a nonlinear manner. Finally, the α-hydroxyl-ω-(sodium carboxylate) PCL salt (HC-PCL) was prepared from HA-PCL and characterized by FT-IR and solution and solid-state NMR. Important differences between CP-MAS and MAS spectra are observed and discussed in terms of morphology and polarization transfer.

The purpose of this work was to explore the effect of the presence of different quantities of SiCpon the cooling curve characteristics, latent heat released and solidification kinetics, associated with the cooling and solidification of Al-Si/SiCpcomposites produced by the stir casting process. An increase in SiCpcontent in A356/SiCpmetal matrix composites produces a shortening of the associated cooling curve and an increase in the eutectic growth temperature with respect to the monolithic metal matrix alloy, cooled under the same experimental conditions. The shortening of the cooling curves could be explained as a result of the measured decrease in the amount of latent heat released during solidification. The increase in the maximum eutectic growth temperature is apparently due to the nucleation of eutectic silicon by SiCpand also to the change in the growth kinetics and morphology of the eutectic Si from fibrous to platelike. IJCMR/422

Microbial transformation studies of the cardiovascular drugs mexrenone (1) and canrenone (2) were conducted. Thirty-nine biotransformations of mexrenone and 84 biotransformations of canrenone were analyzed. Metabolism of the substrate was observed in the majority of these cases. Several monohydroxylated derivatives were detected by HPLC-MS-UV and subsequently identified. Two new mexrenone derivatives, 11α- (3) and 12β-hydroxymexrenone (4), and the known metabolite 6β-hydroxymexrenone (5) were isolated as major products produced by the Beauveria bassiana ATCC 13144 bioconversion (3) and the Mortierella isabellina bioconversion (4 and 5), respectively. Single-elimination products were also sought; however, only the production of the known metabolite Δ^1,2-mexrenone (6) by several bacteria was confirmed. One new monohydroxylated derivative of canrenone, 9α-hydroxycanrenone (7), was isolated as a major product from the Corynespora cassiicola bioconversion. Structure elucidation of all metabolites was based on NMR and HRMS analyses.

The method of densifying in-situ sandy soils using deep vibration (vibro) was first developed in Germany over 60 years ago. Since then the technique has been extended to improve a wide range of soil types for structures of up to 30 storeys in height. A major development in the vibro market worldwide over the last 25 years has been the treatment of soils to resist the effects of liquefaction during seismic events. It is well known that the presence of silt and clay fines inhibits the physical in-situ densification of sandy soils. Experience has shown that a maximum fines content of about 15% would normally permit the performance of vibro compaction methods without the addition of stone aggregate. However, the development of new vibrators and modified construction techniques has enabled sands with significantly higher fines content to be treated. The paper describes how densification of granular soils has progressed with the development of new equipment, the greater appreciation in the manner in which soils respond to both vibration and displacement, and the importance of workmanship during treatment. A number of case histories including in-situ test results, long-term monitoring of ageing effects and references to treated sites already subjected to earthquakes are presented.

Abstract:  Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm.

The Valparaiso 2017 sequence occurred in the Central Chile megathrust, an active zone where the last mega‐earthquake occurred in 1730. Intense seismicity started 2 days before the Mw6.9 mainshock, a slow trenchward movement was observed in the coastal GPS antennas and was accompanied by foreshocks and repeater‐type seismicity. To characterize the rupture process of the mainshock, we perform a dynamic inversion using the strong‐motion records and an elliptical patch approach. We suggest that a slow slip event preceded and triggered the Mw6.9 earthquake, which ruptured an elliptical asperity (semiaxis of 10 km and 5 km, with a subshear rupture, stress drop of 11.71 MPa, yield stress of 17.21 MPa, slip weakening of 0.65 m, and kappa value of 1.98). This earthquake could be the beginning of a long‐term nucleation phase to a major rupture, within the highly coupled Central Chile zone where a megathrust earthquake like 1730 is expected. Valparaiso 2017 Mw6.9 was preceded by repeaters and a slow slip eventAn intense seismicity was recorded before the mainshockThe mainshock broke a small asperity of few kilometers

Bell's inequality dealing with ‘local hidden variables’ is given two formulations in terms ofC*-algebras. In particular, Bell's inequality holds for all states onA?B wheneverA andB are unitalC*-algebras at least one of which is Abelian, i.e., at least one corresponds to a classical physical system.

A case of a 66-year-old woman with a giant fibrovascular polyp protruding from the mouth is presented. The polyp was successfully removed by a cervical esophagotomy.