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Synaptic devices that emulate synchronized memory and processing are considered the core components of neuromorphic computing systems for the low-power implementation of artificial intelligence. In this regard, electrolyte-gated transistors (EGTs) have gained much scientific attention, having a similar working mechanism as the biological synapses. Moreover, compared to a traditional solid-state gate dielectric, the liquid dielectric has the key advantage of inducing extremely large modulation of carrier density while overcoming the problem of electric pinholes, that typically occurs when using large-area films gated through ultra-thin solid dielectrics. Herein we demonstrate a three-terminal synaptic transistor based on ruthenium-doped cobalt ferrite (CRFO) thin films by electrolyte gating. In the CRFO-based EGT, we have obtained multilevel non-volatile conductance states for analog computing and high-density storage. Furthermore, the proposed synaptic transistor exhibited essential synaptic behavior, including spike amplitude-dependent plasticity (SADP), spike duration-dependent plasticity (SDDP), long-term potentiation (LTP), and long-term depression (LTD) successfully by applying electrical pulses. This study can motivate the development of advanced neuromorphic devices that leverage simultaneous modulation of electrical and magnetic properties in the same device and show a new direction to synaptic electronics. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version The authors acknowledge the support from the CRP grant NRF-CRP21-2018-0003 of the National Research Foundation (NRF), Singapore. SNP acknowledges the partial support from the Tier 2 Grant MOE2019-T2-1-117 of the Ministry of Education (MOE) Singapore. PSAK acknowledges support from the Ministry of Education (MoE), India.

Ratchet motion of superconducting vortices, which is a directional flow of vortices in superconductors, is highly useful for exploring quantum phenomena and developing superconducting devices, such as superconducting diode and microwave antenna. However, because of the challenges in the quantitative characterization of the dynamic motion of vortices, a phase diagram of the vortex ratchet motion is still missing, especially in the superconductors with low dimensional structures. Here we establish a quantitative phase diagram of the vortex ratchet motion in a highly anisotropic superlattice superconductor, (SnS)1.17NbS2, using nonreciprocal magnetotransport. The (SnS)1.17NbS2, which possesses a layered atomic structure and noncentrosymmetry, exhibits nonreciprocal magnetotransport in a magnetic field perpendicular and parallel to the plane, which is considered a manifest of ratchet motion of superconducting vortices. We demonstrated that the ratchet motion is responsive to current excitation, magnetic field and thermal perturbation. Furthermore, we extrapolated a giant nonreciprocal coefficient ({\gamma}), which quantitatively describes the magnitude of the vortex ratchet motion, and eventually established phase diagrams of the ratchet motion of the vortices with a quantitative description. Last, we propose that the ratchet motion originates from the coexistence of pancake vortices (PVs) and Josephson vortices (JVs). The phase diagrams are desirable for controlling the vortex motion in superlattice superconductors and developing next-generation energy-efficient superconducting devices.

A Cu-10 Ni-2Ti wt.% alloy has been fabricated by induction melting and casting. The microstructure evolutions of the studied alloy treated with thermal-mechanical treatment were characterized. After homogenized at 950 °C for four hours, hot rolling by 80% at 900 °C solid solution treated at 970 °C for four hours, cold-rolled by 50%, aged at 450 °C for one hour, the hardness, electrical conductivity, tensile strength, yield strength, and the elongation of the studied alloy approached 181 HV, 22.1% IACS, 576 MPa, 486 MPa, and 14.6%, respectively. The studied alloy shows large products of strength and elongation (15.4 GPa·%, 9.3 GPa·%, 8.41 GPa·%, and 10.1 GPa·% for the samples treated with a solid solution, under aged, peak aged, and over-aged states), which are much higher than those of other high strength conductive copper alloys. These findings are helpful in designing new high damage tolerance conductive materials. Keywords: Cu alloy, Damage tolerance, Precipitation, Strength, Microstructure

Neuromorphic computing (NC) is a crucial step toward realizing power-efficient artificial intelligence systems. Hardware implementation of NC is expected to overcome the challenges associated with the conventional von Neumann computer architecture. Synaptic devices that can emulate the rich functionalities of biological synapses are emerging. Out of several approaches, electrolyte-gated synaptic transistors have attracted enormous scientific interest owing to their similar working mechanism. Here, we report a three-terminal electrolyte-gated synaptic transistor based on Fe3O4 thin films, a half-metallic spinel ferrite. We have realized gate-controllable multilevel, non-volatile, and rewritable states for analog computing. Furthermore, we have emulated essential synaptic functions by applying electrical stimulus to the gate terminal of the synaptic device. This work provides a new candidate and a platform for spinel ferrite-based devices for future NC applications.

• Background: This study was designed to investigate the effect of Xuesaitong (XST) capsule added to conventional treatment in patients after percutaneous coronary intervention (PCI) for unstable angina (UA).• Methods: This is a 12-week, randomized, multi-center, double-blinded, placebo-controlled clinical trial. A total of 120 patients with UA will be recruited and randomly allocated in a 1:1 ratio to receive XST or placebo (2 capsules twice per day) on the background of conventional treatment. The changed level of high-sensitivity C-reactive protein from baseline to week 12 is the primary outcome. Secondary outcomes include tumor necrosis factor-α, interleukin-6, platelet aggregation, blood lipid, angina symptoms and ST segment deviation in electrocardiogram. The safety of XST will be monitored during the trial.• Discussion: This study will provide an evidence regarding the efficacy and safety of XST on the background of conventional medical treatment in patients after PCI for UA.• Trial registration: Chinese Clinical Trial Registry, ChiCTR2000032152. Registered on 14 January 2020.

Among various neuromorphic devices for artificial intelligence, the electrochemical transistor, in which the channel conductance can be modulated by the insertion of ions according to the history of gate voltage across the electrolyte, emerges as an efficient one. Despite the striking progress in exploring novel channel materials, few studies report the ferromagnetic metal-based synaptic transistors, limiting their application in synaptic spintronics. Here, we present synaptic modulation of both conductivity as well as magnetism based on the three-terminal electrochemical transistor with a channel of ferromagnetic CoPt alloy. The CoPt metal channel exhibits perpendicular magnetization and anomalous Hall effect. Then, we demonstrated its essential synaptic functionalities, including depression and potentiation of synaptic weight as well as paired-pulse facilitation. Additionally, we are also able to switch the short-term to long-term plasticity transition using different gate parameters, such as amplitude, duration, and frequency. Last, the device presents multilevel reversible and nonvolatile states of conductivity and magnetic coercivity (HC), both of which exhibit satisfying retention behaviours. The results provide a platform to construct future spin-based synaptic devices. Submitted/Accepted version The authors acknowledge funding from the National Research Foundation (NRF), Singapore under its 21st Competitive Research Programs (CRP grant no. NRF-CRP21-2018-0003). X.R.W. acknowledges support from Academic Research Fund Tier 2 (grant no. MOE-T2EP50120-0006) from Singapore Ministry of Education and the Agency for Science, Technology and Research (A*STAR) under its AME IRG grant (project no. A20E5c0094). S. L acknowledges research scholarship from CRP grant.

Artificial synaptic devices capable of synchronized storing and processing of information are the critical building blocks of neuromorphic computing systems for the low-power implementation of artificial intelligence. Compared to the diverse synaptic device structures, the emerging electrolyte-gated synaptic transistors are promising for mimicking biological synapses owing to their analogous working mode. Despite the remarkable progress in electrolyte-gated synaptic transistors, the study of metallic channel-based synaptic devices remains vastly unexplored. Here, we report a three-terminal electrolyte-gated artificial synapse based on metallic permalloy as the active layer. Gating controlled, non-volatile, rewritable, and distinct multilevel conductance states have been achieved for analog computing. Representative synaptic behaviors such as excitatory postsynaptic conductance (EPSC), paired-pulse facilitation (PPF), spike amplitude-dependent plasticity (SADP), spike duration-dependent plasticity (SDDP), and long-term potentiation/depression (LTP/D) have been successfully simulated in the synaptic device. Furthermore, switching from short-term to long-term memory regimes has been demonstrated through repeated training. Benefitting from the short-term facilitation, the synaptic device can also act as a high-pass temporal filter for selective communication. This research highlights the great potential of metallic channel-based synaptic devices for future neuromorphic systems and augments the diversity of synaptic devices. Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version The authors acknowledge the support from the CRP Grant NRF-CRP21-2018-0003 of the National Research Foundation (NRF), Singapore. SNP acknowledges the partial support from the Tier 2 grant MOE2019-T2-1-117 of the Ministry of Education (MOE) Singapore. PSAK acknowledges support from the Ministry of Education (MoE), India.

FeTe

Microalloying is an effective method to improve the comprehensive properties of copper alloys. The effects of magnesium on the microstructure, mechanical properties and anti-stress relaxation properties of CuNiSi alloys have been investigated. Results demonstrated that magnesium plays significant roles in refining the dendritic microstructure of the as-cast ingot, accelerating the precipitation decomposition, improving the mechanical properties and increasing the anti-stress relaxation properties. The incremental strength increase is due to the Orowan strengthening from the nanoscale Ni2Si and Ni3Al precipitates. As compared with the Cu–6.0Ni–1.0Si–0.5Al (wt%) alloy, the ultimate tensile strength of the designed Cu–6.0Ni–1.0Si–0.5Al–0.15Mg (wt%) alloy increases from 983.9 to 1095.7 MPa, and the electrical conductivity decreases from 27.1 to 26.6% IACS, respectively. The stress relaxation rates of the designed Cu–6.0Ni–1.0Si–0.5Al–0.15Mg alloy are 4.05% at 25 °C, 6.62% at 100 °C and 9.74% at 200 °C after having been loaded for 100 h, respectively. Magnesium significantly promotes nucleation during precipitation and maintains small precipitate size.

Since the 1980s, Sargassum fusiforme has been cultivated in Zhejiang, South China, and nowadays it becomes one of the important commercial seaweeds in China. With traditions of eating habits in the East Asian countries, this brown alga is used as food, because it contained functional oligo/polysaccharides and chemical components. and was regarded playing roles in antioxidant activities and regulating immunology. Through over 15 years’ selection, breeding and cultivation, we obtained three strains with good traits and testified their characters during the production, which included the cultivars with high yield and other two good characters, either all the selected strains were applied in the Sargassum production. To avoid confusion during the selection and nursery, it was preferred to establish one fingerprint for distinguishing the Sargassum cultivars from different strains. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) methods were adopted to analyze the genetic diversities of the selected S. fusiforme strains. With that, one fingerprint with RAPD markers was constructed, and one sequence characterized amplified region (SCAR) marker to S. fusiforme was obtained. It is indicated that the applied fingerprint could be valid in S. fusiforme genetic and germplasm justification, and will be positive to molecular marker assistance in its selection and cultivation.

A Cu–6.0 Ni–1.0 Si–0.5 Al (wt%) alloy was fabricated, and its phase transformation behavior in the early stages of aging treatment were studied systematically, including the mechanical properties, type of precipitates, formation heat of precipitates, elastic strain energy, crystal orientation relationships, and spatial distribution of elements. The experimental results demonstrate that a B2 ordering structured β-NiAl precipitate formed in the matrix as the supersaturation solid solution (SSS) was aged at 400 °C; δ-Ni2Si, a L12 ordering structured β-Ni3Si, and L12 structured γ′-Ni3Al were precipitated from the matrix aged at 450 °C; and discontinuous δ-Ni2Si precipitates occurred in the matrix aged at 500 °C and above. Atom probe results revealed that Ni and Si formed clusters with a size of 1–2 nm, and Al tended to segregate around these clusters as the SSS was aged at 450 °C. The ultimate tensile strength of the studied alloy was 1080.2 ± 20.4 MPa for the sample aged at 450 °C for 1 h, and the electrical conductivity was 25.4% IACS. Sketch maps of the crystal orientation relationships between the matrix and precipitates were also established.

Empowering conventional materials with unexpected magnetoelectric properties is appealing to the multi-functionalization of existing devices and the exploration of future electronics. Recently, owing to its unique effect in modulating a matter's properties, ultra-small dopants, for example, H, D, and Li, attract enormous attention in creating emergent functionalities, such as superconductivity, and metal–insulator transition. Here, an observation of bipolar conduction accompanied by a giant positive magnetoresistance in D-doped metallic Ti oxide (TiOxDy) films is reported. To overcome the challenges in intercalating the D into a crystalline oxide, a series of TiOxDy is formed by sequentially doping Ti with D and surface/interface oxidation. Intriguingly, while the electron mobility of the TiOxDy increases by an order of magnitude larger after doping, the emergent holes also exhibit high mobility. Moreover, the bipolar conduction induces a giant magnetoresistance up to 900% at 6 T, which is ≈6 times higher than its conventional phase. This study paves a way to empower conventional materials in existing electronics and induce novel electronic phases. Ministry of Education (MOE) National Research Foundation (NRF) Accepted version

FeTe1-xSe x, a promising layered material used to realize Majorana zero modes, has attracted enormous attention in recent years. Pulsed laser deposition (PLD) and molecular-beam epitaxy (MBE) are the routine growth methods used to prepare FeTe1-xSexthin films. However, both methods require high-vacuum conditions and polished crystalline substrates, which hinder the exploration of the topological superconductivity and related nanodevices of this material. Here we demonstrate the growth of the ultrathin FeTe1-xSex superconductor by a facile, atmospheric pressure chemical vapor deposition (CVD) method. The composition and thickness of the two-dimensional (2D) FeTe1-xSex nanosheets are well controlled by tuning the experimental conditions. The as-prepared FeTe0.8Se0.2 nanosheet exhibits an onset superconducting transition temperature of 12.4 K, proving its high quality. Our work offers an effective strategy for preparing the ultrathin FeTe1-xSex superconductor, which could become a promising platform for further study of the unconventional superconductivity in the FeTe1-xSex system. Accepted version

Indium oxide (In2O3) hollow microspheres were prepared using yeast as a bio-template with the aid of a precipitation method. The yeast provided a solid frame for the deposition of In(OH)3 to form the precursor. The resulting In2O3 hollow microspheres were obtained by calcining the precursor at 650 °C. The samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption–desorption isotherms and UV–Vis diffuse reflectance spectroscopy. The results showed that the diameter of the In2O3 hollow microspheres was about 2.0–3.0 μm and the spherical shells were composed of In2O3 nanoparticles with a size of ∼20 nm. The BET specific surface area of the sample was 19.23 m2 g−1. The photoelectrocatalytic test results showed that the photoelectrocatalytic degradation efficiency of methylene blue (MB) using In2O3 hollow microspheres as catalysts under visible light irradiation and a certain voltage could reach above 95% after 4 hours, much higher than that of only photodegradation. The enhanced photoelectrocatalytic activity could be attributed to the hydroxyl radicals HO˙ produced by the light irradiation reaction process which could oxidize the electron donors and were beneficial to reducing the recombination of electrons and holes.

A new rust converter, 3,4,5-trihydroxy-2-[(hydroxyimino) methyl] benzoic acid (named as RC-GAO), has been synthesized based on gallic acid by formylation and oximation. The synthesis was confirmed by Fourier transform infrared spectroscopy studies. The nature and morphology of rust and conversion layer on the rusty samples were characterized by scanning electron microscopy and X-ray diffraction. The corrosion resistance of the residual rust coatings containing the rust converter on the rusty sample was measured by the salt spray test. The results showed that the synthesized rust converter possessed excellent chelating capability with rust and significant anticorrosive performance.The synthesized rust converter revealed excellent chelating capability with rust and significant anticorrosive performance

Background and aim Despite optimal secondary preventive treatment, patients with stable coronary artery disease (SCAD) remain at high risk of cardiovascular events. This multicenter, double-blinded, randomized trial sought to determine whether the addition of Qing-Xin-Jie-Yu Granule (QXJYG), a traditional Chinese medicine prescription, to standard therapy would further reduce risk of cardiovascular events in patients with SCAD. Methods A total of 1500 patients with documented SCAD were randomly assigned in a 1:1 ratio to QXJYG or placebo for 6 months, and followed up for another 6 months. The primary outcome was a composite of cardiovascular death, nonfatal myocardial infarction (MI) and coronary revascularization. Near the end of the trial, but before unblinding, a commonly used composite ‘hard’ endpoint composed of cardiovascular death, nonfatal myocardial infarction and ischemic stroke was additionally analyzed. Results During a median follow-up of 12 months, no significant difference of the primary outcome between the two groups was observed (1.59% vs. 1.62%; hazard ratio, 0.41; 95% CI, 0.13–1.28). However, absolute risk of the composite ‘hard’ endpoint was reduced by 0.99% (0.31% vs. 1.30%; hazard ratio, 0.06; 95%CI, 0.01 to 0.53). No difference of adverse events between the two groups was observed. Conclusion In patients with SCAD, the addition of QXJYG to standard therapy was associated with reduced risk of nonfatal MI and the composite ‘hard’ endpoint of cardiovascular death, nonfatal MI and stroke. ( http://www.chictr.org.cn/showproj.aspx?proj=5200 , ChiCTR-TRC-13004370).

New generation wearable devices require mechanically compliant strain sensors with a high sensitivity in a full detecting range. Herein, novel 2D end-to-end contact conductive networks of multi-walled carbon nanotubes (MWCNTs) were designed and realized in an ethylene-α-octene block copolymer (OBC) matrix. The prepared strain sensor showed a high gauge factor (GF) of 248 even at a small strain (5%) and a linear resistance response throughout the whole strain range. The sensors also exhibited very good stretchability up to 300% and high cycling durability. This novel design solved the intrinsic problem of sensors based on carbon nanotube bundles, i.e., a long sliding phase before the disconnection of CNTs in a cost-effective and scalable way. This study rationalizes the 2D end-to-end contact concept to improve the sensitivity of the existing sensors and has great potential to be used in a wide variety of polymer based sensors.

Indium oxide (In

The SPIRIT Checklist. (DOC 123 kb)

SPIRIT figure. (DOCX 23 kb)

Hizikia fusiformis is one of the important commercially cultivated seaweeds in China. Inter-simple sequence repeats (ISSR) and sequence-related amplified polymorphism (SRAP) markers were used to assess genetic structure of nine wild H. fusiformis populations collected along the coast of China. Of the 255 bands generated by 21 ISSR primers, 99.61% were polymorphic and 99.71% of 344 bands amplified by 30 SRAP primers were polymorphic. The tested high genetic diversities show that the average Nei's genetic diversity (H) were 0.1519 and 0.1624, and average Shannon's information index (I) were 0.2248 and 0.2400 in ISSR and SRAP analyses, respectively. Unweighted pair group method with arithmetic mean (UPGMA) dendrograms of the nine populations were divided into two main groups. The ISSR and SRAP analyses values of gene differentiation (G (ST), 0.5955, 0.5486, respectively) indicate that high variation exists among the nine populations, likely due to external interferences and limitation of gene flow (N (m) = 0.3397, 0.4114). Our study indicated that human activities and herbivore overgrazing had influenced the natural Hizikia populations and that the understanding of population genetics would be helpful in sustainable utilization and biomass conservation of Sargassaceae resources.

Background Recurrent cardiovascular event remains high in stable coronary artery disease (SCAD), especially in patients with multiple risk factors, despite a high rate of use conventional treatment. Traditional Chinese Medicine (TCM) is a promising complementary and alternative medicine for treating SCAD, while evidence for its effect on long-term survival is limited. This study was designed to test if Chinese herbal medicine in addition to conventional treatment is more effective than conventional treatment alone in reducing major adverse cardiac event (MACE) for SCAD patients with multiple risk factors during a 1-year follow-up. Methods This is a multicenter, placebo-controlled, double-blinded, randomized controlled clinical trial. A total of 1500 patients are randomized in a 1:1 ratio to receive the Qing-Xin-Jie-Yu Granules (QXJYG) or the placebo granules, twice daily for 6 months. The primary outcome is the combined outcomes including cardiac death, nonfatal myocardial infarction and revascularization. The secondary outcome is the combined outcomes including all-cause mortality, re-admission for acute coronary syndrome (ACS), heart failure, malignant supraventricular and ventricular arrhythmia influencing hemodynamics, ischemic stroke, and other thromboembolic events during 1-year follow-up. The assessment is performed at baseline (before randomization), 1, 3, 6, 9, and 12 months after randomization. Discussion This is the first multicenter trial sponsored by the national funding of China to evaluate TCM in combination with conventional treatment on 1-year survival in high-risk SCAD patients. If successful, it will provide an evidence-based complementary therapeutic approach for reducing MACE from SCAD. Trial registration The trial was registered in the Chinese Clinical Trial Registry on December 28, 2013. The registration number is ChiCTR-TRC-13004370. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1569-9) contains supplementary material, which is available to authorized users.