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A sharp thermal contrast between the cold forearc and the hot arc and backarc is considered fundamental to various subduction-zone processes. However, direct observational evidence for this contrast is rather limited. If this contrast is present, it must cause a rheological contrast in the mantle wedge: elastic in the forearc and viscoelastic in the arc and backarc for the timescale of earthquake cycles. Here we demonstrate that postseismic deformation following large subduction earthquakes provides independent evidence for the thermally controlled rheological contrast. Specifically, we show that seaward postseismic motion is deflected upward at the edge of the cold forearc mantle wedge, causing diagnostic uplift just seaward of the volcanic arc. From numerical simulations of postseismic deformation following the 2011 moment magnitude (Mw) 9 Tohoku-oki, 2010 Mw 8.8 Maule, 2007 Mw 8.4 Bengkulu and 1960 Mw 9.5 Chile earthquakes, together with a global synthesis of postseismic uplift measurements, we find that cold forearc mantle is present irrespective of the diversity in tectonic settings. Our findings also indicate that field surveys eight years after the 1960 Chile earthquake provided some of the earliest evidence for viscoelastic postseismic deformation. We suggest that the established link between long-term thermal processes and short-term earthquake cycle deformation is important to understanding subduction-zone dynamics. Deformation after large subduction earthquakes reflects the thermal contrast between the mantle wedge and its nose, according to numerical simulations and a synthesis of postseismic uplift data from subduction zones.

We observe high optical quality factor (Q) polygonal and star coherent optical modes in a lithium niobate microdisk. In contrast to the previous polygon modes achieved by deformed microcavities at lower mechanical and optical Q, we adopt weak perturbation from a tapered fiber for the polygon mode formation. The resulting high intracavity optical power of the polygon modes triggers second harmonic generation at high efficiency. With the combined advantages of a high mechanical Q cavity, we observe optomechanical oscillation in polygon modes for the first time. Finally, we observe frequency microcomb generation from the polygon modes with an ultrastable taper-on-disk coupling mechanism.

Herein, glucose and H2O2 stimuli-responsive vesicles are constructed based on host–guest interaction between a diblock copolymer, poly(ethylene glycol)-b-poly[3-acrylamidophenylboronic acid-co-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl acrylate], (PEG-b-P(PBA-co-PBEM), BCP for short) and α-cyclodextrin. In the presence of glucose, the vesicles are transformed to giant swollen spherical micelles because of the formation of a negatively charged tetravalent form between phenylboronic acid and glucose. On the other hand, the vesicles are totally disassembled when they are exposed to H2O2, which is due to the H2O2-mediated degradation of the pendant phenylboronic acid pinacol ester. The glucose and H2O2 stimuli-responsive vesicles are then applied in the controlled release of water-soluble anticancer drug, doxorubicin hydrochloride (DOX). Upon external stimuli, the DOX displays a faster release rate than that without stimuli. Moreover, the polymeric vesicles show an excellent cytocompatibility toward MCF-7 cells, and the drug-loaded vesicles exhibit a lower cytotoxicity than free drug toward cancer cells. The drug-loaded vesicles can be taken up by MCF-7 cells and further release the DOX in cancer cells due to the high glucose and H2O2 concentration in tumor cells, while they have negligible effect on normal cells, which may be important for applications in the therapy of cancers as a controlled-release drug carrier.

Herein, a dual-responsive insulin delivery device by integrating glucose- and H2O2-responsive polymeric vesicles (PVs) with transcutaneous microneedles (MNs) has been designed. This novel microneedle delivery device achieves a goal of fast response, excellent biocompatibility, and painless administration. The PVs are self-assembled from a triblock copolymer including poly(ethylene glycol), poly(phenylboronic acid) (glucose-sensitive block), and poly(phenylboronic acid pinacol ester) (H2O2-sensitive block). After loading with insulin and glucose oxidase (GOx), the drug-loaded PVs display a basal insulin release as well as a promoted insulin release in response to hyperglycemic states. The insulin release rate responds quickly to elevated glucose and can be further promoted by the incorporated GOx, which will generate the H2O2 at high glucose levels and further break the chemical links of phenylboronic acid pinacol ester group. Finally, the transdermal delivery of insulin to the diabetic rats ((insulin + GO...

Minimizing data misfit has been widely used in geodetic determination of fault dip angle, however, it ignores the contribution from data noise. Here, we use the jℛi criterion, which takes into account both data misfit and the contribution from data noise, to determine dip angle. Synthetic tests show dip angle estimates with the jℛi criterion are more accurate and robust than those with data misfit minimization. We applied this jℛi criterion to the determination of the dip angle of the 2015 Mw 7.9 Gorkha Nepal earthquake using Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) data. The results show that the event ruptured to the north of Kathmandu with a maximum slip value of 5.8 m and a dip angle of 9.5°. We also calculated the coulomb failure stress changes resolved onto the receiver faults that are generally consistent with the fault geometry of this event, suggesting the possible triggering relation to aftershocks with low dip angles and a zone of seismic potential located to the west of the rupture zone.

On 1st April 2007 a Mw 8.1 megathrust earthquake occurred in the western Solomon Islands of the Southwest Pacific and generated a regional tsunami with run-up heights of up to 12 m. A Bayesian inversion model is constructed to derive fault dip angle and cumulative co-seismic and early post-seismic slip using coral reef displacement measurements, in which both data misfit and moment magnitude are used as constraints. Results show three shallow, high-slip patches concentrated along the trench from west of Ranongga Island to Rendova Island on a fault plane dipping 20°, and a maximum dip slip of 11.6 m beneath Ranongga Island. Considerable subsidence on Simbo Island outboard of the trench on the subducting plate is not well explained with this model, but may be related to the effects of afterslip and/or Simbo Island’s location near the triple junction among the Australia, Woodlark and Pacific plates.

Near-infrared (NIR) irradiation responsive drug delivery systems have many advantages, which have attracted extensive interest from researchers. In this study, a NIR-triggered drug release system was established by grafting upper critical solution temperature (UCST) polymers on the surface of hollow mesoporous silica nanoparticles (HMSNs) followed by treatment with the photothermal conversion agent indocyanine green (ICG). The as-prepared UCST polymers showed the clearing temperature of 45 °C, which were advantageous to serve as gatekeepers in the physiological environment (37 °C). Under NIR irradiation, the temperature of the solution was elevated above the clearing point due to the presence of ICG; consequently, the collapsed UCST polymer chains became more hydrophilic; this resulted in the exposure of the mesoporous channels of the HMSNs and achievement of a burst drug release. Moreover, this NIR-responsive delivery system showed good biocompatibility and high anticancer efficiency towards the MCF-7 cancer cells upon exposure to NIR irradiation. In addition, a synergistic effect of thermal and chemo treatment has been achieved by the application of NIR irradiation since cancer cells are more vulnerable to high temperatures than normal cells.

We demonstrate efficient tuning of a monolithically integrated lithium niobate (LN) microdisk optical frequency microcomb. Utilizing the high optical quality (Q) factor (i.e., Q∼7.1×106) of the microdisk, the microcomb spans over a spectral bandwidth of ∼200nm at a pump power as low as 20.4 mW. Combining the large electro-optic coefficient of LN and the optimum design of the geometry of microelectrodes, we demonstrate electro-optical tuning of the comb with a spectral range of 400 pm and a tuning efficiency of ∼38pm/100V.

A highly sensitive sensor based on a D-shaped microfiber with high birefringence is theoretically and experimentally demonstrated. The fiber is fabricated by side-polishing a single-mode fiber and then tapering down the polished region into a micrometer size. Through analyzing the electric field distribution of the evanescent wave, the relationship between the structural parameters and the birefringence value of the D-shaped microfiber is established. Simulation results reveal that the maximum birefringence is always achieved at the biggest ratio of the removed depth to the microfiber diameter, i.e., $h/D$ for a certain diameter. By optimizing the diameter and $h/D$ , fantastic birefringence of $4.8\times 10^{-2}$ is achieved, as well as the enhanced refractive index (RI) and temperature sensitivity can be realized when the group birefringence $G$ approaches to zero. By utilizing Sagnac loop interferometer, high RI sensitivity of 9951 nm/RIU and temperature sensitivity up to −0.989 nm/°C are obtained with the microfiber diameter of $2.724~\mu \text{m}$ and the length of only 15 mm in experiment.

Combined the large evanescent field of microfiber with the high thermal conductivity of graphene, a sensitive all-fiber temperature sensor based on graphene-assisted micro fiber is proposed and experimentally demonstrated. Microfiber can be easily attached with graphene due to the electrostatic 6 force, resulting in an effective interaction between graphene and the evanescent field of microfiber. The change of the ambient temperature has a great influence on the conductivity of graphene, leading to the variation of the effective refractive index of microfiber. Consequently, the optical power transmission will be changed. The temperature sensitivity of 0.1018 dB/°C in the heating process and 0.1052 dB/°C in the cooling process as well as a high resolution of 0.0098 °C is obtained in the experiment. The scheme may have great potential in sensing fields owing to the advantages of high sensitivity, compact size, and low cost.

After a great subduction earthquake, viscoelastic stress relaxation causes prolonged seaward motion of inland areas of the upper plate, as was observed around the turn of the century in the area of the 1960 Mw 9.5 Chile earthquake with Global Navigation Satellite System (GNSS) measurements. However, recent GNSS observations during 2010–2019 indicate a systematic decrease in the velocity of the seaward motion over a region covering the latitudinal range of the southern half of the 1960 rupture. Data from the only long-lived continuous site in this region (COYQ since 1997), situated over 200 km away from the trench, suggest that the decrease in the seaward velocity (or increase in the landward velocity) occurred within a few years prior to 2010. This rapid and regional change cannot be explained by viscoelastic relaxation. We thus propose that the change was caused by a relatively sudden downdip widening of the zone of locking along the megathrust. Using three-dimensional finite element modelling, we find that the observed velocity change cannot be otherwise explained, although the amount of the increase in locking cannot be uniquely determined because of trade-offs between, and uncertainties in, the various parameters involved. For example, the degree of the increase in locking is affected by the value of coseismic slip in 1960 in the southernmost part of the rupture zone. A postseismic deformation model with greater coseismic slip in accordance with the most recent coseismic slip model in the literature better fits COYQ data prior to 2005 and requires greater locking increase afterwards. A model with less coseismic slip requires less locking increase but an additional long-term slow slip event prior to 2005. The rapid surface velocity change and the inferred increase in megathrust locking several decades after a great earthquake present new challenges to the understanding of fault mechanics and subduction zone dynamics.

Total-ionizing dose effects on the resistive switching properties of HfO2/Al2O3 bipolar resistive-random-access-memory devices under 60Co γ irradiation were investigated in this study. Insignificant impact was found for 60Co γ irradiation with a dose of 200 krad (Si) but the impact became significant for higher irradiation intensity of 1 Mrad (Si). The experiment results indicated that it is possible for device high resistance off-state or low resistance on-state to change after a total ionizing dose step stress threshold being surpassed. Moreover, it was found that the 60Co γ irradiation of 1 Mrad (Si) caused degradation of device high-resistance state, low-resistance state, set/reset voltages, and endurance characteristics, due to the simultaneous induce of oxygen vacancies and displacement damage.

Three-dimensional surface displacement field associated with the 25 April 2015 Gorkha, Nepal earthquake is derived from an integration of Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) measurements, with an extended SISTEM (Simultaneous and Integrated Strain Tensor Estimation From Geodetic and Satellite Deformation Measurements) approach (ESISTEM) proposed in this study. In ESISTEM approach, both surrounding InSAR and GPS measurements can be used as constraints in deriving surface displacements; while only surrounding GPS measurements are used in SISTEM approach. Besides the constraints from surrounding GPS measurements, the ESISTEM approach makes surrounding InSAR measurements available for constraining the derived deformations based on surface elastic theory for the first time. From the north to the south, derived surface displacement field shows prevailing southward horizontal deformations, and gradually varied vertical deformations ranging from −0.95 to 1.40 m within 120 km to the north of Kathmandu. This reveals that ruptures of Main Himalayan thrust (MHT) system were confined in subsurface and did not propagate to the Main Frontal Thrust (MFT) fault, in accordance with field investigation as well as geodetic and seismic studies. Relation between vertical deformations and earthquake-induced landslides is briefly discussed.

We consider the design of computationally efficient online learning algorithms in an adversarial setting in which the learner has access to an offline optimization oracle. We present an algorithm called Generalized Follow-the-Perturbed-Leader and provide conditions under which it is oracle-efficient while achieving vanishing regret. Our results make significant progress on an open problem raised by Hazan and Koren, who showed that oracle-efficient algorithms do not exist in general and asked whether one can identify properties under which oracle-efficient online learning may be possible. Our auction-design framework considers an auctioneer learning an optimal auction for a sequence of adversarially selected valuations with the goal of achieving revenue that is almost as good as the optimal auction in hindsight, among a class of auctions. We give oracle-efficient learning results for: (1) VCG auctions with bidder-specific reserves in single-parameter settings, (2) envy-free item pricing in multi-item auctions, and (3) s-level auctions of Morgenstern and Roughgarden for single-item settings. The last result leads to an approximation of the overall optimal Myerson auction when bidders' valuations are drawn according to a fast-mixing Markov process, extending prior work that only gave such guarantees for the i.i.d. setting. Finally, we derive various extensions, including: (1) oracle-efficient algorithms for the contextual learning setting in which the learner has access to side information (such as bidder demographics), (2) learning with approximate oracles such as those based on Maximal-in-Range algorithms, and (3) no-regret bidding in simultaneous auctions, resolving an open problem of Daskalakis and Syrgkanis., Comment: An earlier version of this paper appeared in FOCS 2017

Based on hybrid WDM/TDM/FDM, a 3D encoded microstructure sensor network with ultra-high capacity up to 32000 is proposed. The competitive sensing performances are experimentally demonstrated in a prototype system with 64 sensors.