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The robotic frog’s body is compact and the total mass is 1.29kg. Different paddling gaits were tested to investigate swimming performance. The results show that the robotic frog has agile swimming ability and high environmental adaptability. The robotic frog can swim forward more than 0.6m (3.4 times the body length) in one paddling gait cycle(6s), whose average swimming velocity is about 0.1m/s . And the minimum turning radius is about 0.15m(less than 1 time the body length). © 2020 IOP Publishing Ltd.Using Su-Schrieffer-Heeger Hamiltonian and exploiting Green’s function method in the framework of Landauer-Büttiker formalism, the topological and spin dependent electron transport properties of a trans polyacetylene molecule are studied. It is found that molecules with intracell single carbon-carbon bonding and even monomers in their chains have two edge states and possess topological properties though their Hamiltonians do not respect chiral symmetry. A perpendicular exchange magnetic field and two perpendicular and transverse electric fields are used to induce and manipulate the quantum spin dependent transport properties. The exchange field induces spin polarization in different electron energy regions which are expanded by stronger exchange fields. Therefore this proposed device works as a perfect spin filter. The spin polarization can be manipulated by applying the perpendicular electric field and remains robust against the transverse electric field variations. © 2020 IOP Publishing Ltd.Hot electron photodetection (HEPD) excited by surface plasmon can circumvent bandgap limitations, opening pathways for additional energy harvesting. However, the costly and time-consuming lithography has long been a barrier for large-area and mass production of HEPD. In this paper, we proposed a planar and electron beam lithography-free hot electron photodetector based on the Fabry-Pérot resonance composed of Au/MoS2/Au cavity. The hot electron photodetector has a nanoscale thickness, high spectral tenability, and multicolour photoresponse in the near-infrared region due to the increased round-trip phase shift by using high refractive index MoS2. We predict that the photoresponsivity can achieve up to 23.6 mA/W when double cavities are integrated with the Fabry-Pérot cavity. The proposed hot electron photodetector that has a nanoscale thickness and planar stacking is a perfect candidate for large-area and mass production of HEPD. © 2020 IOP Publishing Ltd.The band structure of the quasi-one-dimensional transition metal trichalcogenide ZrS3(001) was investigated using nanospot angle resolved photoemission spectroscopy (nanoARPES) and shown to have many similarities with the band structure of TiS3(001). We find that ZrS3, like TiS3, is strongly n-type with the top of the valence band ~1.9 eV below the Fermi level, at the center of the surface Brillouin zone. The nanoARPES spectra indicate that the top of the valence band of the ZrS3(001) is located at Γ. The band structure of both TiS3and ZrS3exhibit strong in-plane anisotropy, which results in a larger hole effective mass along the quasi-one-dimensional chains than perpendicular to them. © 2020 IOP Publishing Ltd.Efficient optical sensing is desirable for wide applications. For the sensors, the spectral factors of the sensitivity (S) and the figure of merit (FoM) and the intensity change related figure of merit (FOM*) are all the key points for sensing measurement. In this work, we propose and demonstrate a novel high-performance plasmonic sensor platform via using a resonant cavity array grating under the oblique excitation. Ultra-sharp absorption mode with the bandwidth down to 1.3 nm is achieved when the oblique angle is 7.5o. During the sensing of the Na+ (Cl-) ions in the solution, the spectral S and FoM factors reach 568 nm/RIU (refractive index unit) and 436, respectively. The minimum detection limit is as low as 3.521 × 10-6 RIU. The FOM* factor is simultaneously up to 907. Moreover, the spectral intensity change is up to 57% when only 1% concentration change is introduced for the solution. The detection limit of the ions’ concentration can be as low as 0.002%. The sensor has great potential applications due to its ultrahigh S, FoM and FOM*. © 2020 IOP Publishing Ltd.PURPOSE To reduce the variability of radiomics features caused by computed tomography (CT) imaging protocols through using a generative adversarial network (GAN) method. MATERIAL AND METHODS In this study, we defined a set of images acquired with a certain imaging protocol as a domain, and a total of 4 domains (A, B, C, and T [target]) from 3 different scanners were included. In dataset#1, 60 patinets for each domain were collected. Datasets#2 and #3 included 40 slices of spleen for each of the domains. In dataset#4, the slices of 3 colorectal cancer groups (n = 28, 38, and 32) were separately retrieved from 3 different scanners, and each group contained short-term and long-term survivors. 77 features were extracted for evaluation by comparing features distributions. First, we trained the GAN model on dataset#1 to learn how to normalize images from domains A, B, and C to T. Next, by comparing feature distributions between normalized images of the different domains, we identified the appropriate model and assessed it , in dataset #2 and dataset#3, respectively. Finally, to investigate whether our proposed method could facilitate multicenter radiomics analysis, we built the lasso classifier to distinguish short-term from long-term survivors based on a certain group in dataset#4, and validate it in another two groups, which formed a cross-validation between groups in dataset#4. RESULTS After normalization, the percentage of aligned features between domains A vs T, B vs T, and C vs T increased from 10.4 %, 18.2%, and 50.1% to 93.5%, 89.6%, and 77.9%, respectively. In the cross-validation results, average improvement of the area under the receiver operating characteristic curve achieved 11% (3%-32%). CONCLUSION Our proposed GAN-based normalization method could reduce the variability of radiomics features caused by different CT imaging protocols and facilitate multicenter radiomics analysis. © 2020 Institute of Physics and Engineering in Medicine.The low electronic conductivity and large volume variation result in inferior lithium storage performance of ZnO. To overcome these shortcomings of ZnO, herein, ZnO nanoparticles are encapsulated in resorcinol-formaldehyde resin-derived hard carbon and then further assembled to 3-dimensional mesoporous framework structure by polyvinyl pyrrolidone-derived soft carbon network. The synthesis methods include the polymerization of resorcinol-formaldehyde resin and a polyvinyl pyrrolidone-boiling method. ZnO@dual carbon is of large specific surface area (153.7 m2 g-1) and high porosity. It exhibits excellent cycling performance and high rate capability. After 350 cycles at 500 mA g-1, ZnO@dual carbon still delivers discharge capacity of 701 mAh g-1 while actual discharge capacity of ZnO reaches 950.9 mAh g-1. At 2 A g-1, ZnO@dual carbon delivers the average discharge capacity of 469.6 mAh g-1. Electrochemical performance of ZnO@dual carbon is remarkably superior to those of ZnO@single carbon, pure carbon and pure ZnO nanoparticles, demonstrating the superiority of the dual carbon-assembling structure. This composite structure greatly improves structure stability of ZnO, enhances electron conductivity of ZnO as well as overall electron transport; facilitates electrolyte penetration and Li ions diffusion, leading to improved cycling stability and good rate capability. © 2020 IOP Publishing Ltd.Insects with asynchronous flight muscles are believed to flap at the effective fundamental frequency of their thorax-wing system. Flapping in this manner leverages the natural elasticity of the thorax to reduce the energetic requirements of flight. However, to the best of our knowledge, the fundamental frequency of the insect wing-muscle-thorax system has not been measured. Here, we measure the linear frequency response function (FRF) of honeybee Apis mellifera thoraxes about their equilibrium state in order to determine their fundamental frequencies. FRFs relate the input force to output acceleration at the insect tergum and are acquired via a mechanical vibration shaker assembly. When compressed 50 micron, the thorax fundamental frequency averaged across all subjects was about 50% higher than reported wingbeat frequencies. We suspect that the measured fundamental frequencies are higher in the experiment than during flight due to boundary conditions and posthumous muscle stiffening. Next, we compress the thorax between 100 – 300 micron in 50 micron intervals to assess the sensitivity of the fundamental frequency to geometric modifications. For all specimens considered, the thorax fundamental frequency increased nearly monotonically with respect to level of compression. This implies that the thorax behaves as a nonlinear hardening spring when subject to large displacements, which we confirmed via static force-displacement testing. While there is little evidence that insects utilize this non-linearity during flight, the hardening characteristic may be emulated by small resonant-type flapping wing micro air vehicles to increase flapping frequency bandwidth. Overall, methods established through this work provide a foundation for further dynamical studies on insect thoraxes moving forward. © 2020 IOP Publishing Ltd.Thin films with stable half-metallic (HM) character and 100% spin-polarization (SP) are required to be used in spintronic devices. The HM character has been predicted theoretically in many Heusler alloys thin films and confirmed by experiments. Full-Heusler alloy Ti2FeSn has been studied extensively. It has been reported that their (001)-oriented thin films with TiFe or TiSn terminations preserve 100% SP, but the HM character is unstable because the edge of the bandgap is closed to the Fermi level EF. Therefore, we investigate the effects of the Co-doping on the structural, electronic and magnetic properties of the bulk full-Heusler alloys Ti2Fe1‒xCoxSn (x=0.00, 0.25, 0.50, 0.75 or 1.00) and their (001)-oriented thin films. The bulk Ti2Fe1‒xCoxSn (x=0.00, 0.25, 0.50, 0.75 or 1.00) alloys are all HM ferromagnets. We investigate twelve possible terminations and show that five of them preserve HM character with 100% SP at the Fermi level EF, while in the remaining seven, surface states emerge in the spin-down channel at the Fermi level EF, significantly reducing their SP. The Co-doping significantly increases the stability of the TiSn slab, also increases its spin-down bandgap E_g^↓ and HM gap E_g^HM at x=0.50. The stable HM character makes it is a slab of maximum benefit in the applications of spintronic devices, especially in magnetic tunnel junctions. © 2020 IOP Publishing Ltd.Objective.Carbon fiber electrodes may enable better long-term brain implants, minimizing the tissue response commonly seen with silicon-based electrodes. The small fiber diameter may enable high-channel count brain-machine interfaces capable of reproducing dexterous movements. selleck chemicals Past carbon fiber electrodes exhibited both high fidelity single unit recordings and a healthy neuronal population immediately adjacent to the recording site. However, the recording yield of our carbon fiber arrays chronically implanted in the brain typically hovered around 30%, for previously unknown reasons. In this paper we investigated fabrication process modifications aimed at increasing recording yield and longevity.Approach.We tested a new cutting method using a 532nm laser against traditional scissor methods for the creation of the electrode recording site. We verified the efficacy of improved recording sites with impedance measurements andin vivoarray recording yield. Additionally, we tested potentially longer-lasting coating alternatives to PEDOTpTS, including PtIr and oxygen plasma etching.