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Reversible proton‐conducting solid oxide cells (R‐PSOCs) are considered to be one of the most promising devices for efficient power generation and hydrogen production. However, the requirement of high catalytic activity for fast oxygen reduction/evolution reaction (ORR/OER) and durability under high steam concentration of air electrode materials remains the major challenge for the practical application of R‐PSOCs. Here, a series of cobalt‐free Ruddlesden–Popper perovskite of Nd0.8Sr1.2Ni1‐xFexO4±δ are reported with mixed conductivity for enhanced ORR/OER kinetics. The R‐PSOCs with an optimal Nd0.8Sr1.2Ni0.7Fe0.3O4±δ air electrode show a high peak power density of 1.28 W cm−2 in the fuel cell mode and a promising current density of 3.24 A cm−2 at 1.3 V in the electrolysis cell mode at 700 °C. In addition, the R‐PSOCs show favorable stability under the fuel cell, electrolysis, and reversible modes for hundreds of hours. This work demonstrates that the Ruddlesden–Popper materials can be utilized as suitable air electrodes for R‐PSOCs. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) with the Gd 0.1 Ce 0.9 O 1.95 (GDC) diffusion barrier layer require the densification of GDC to improve the performance of the cells. In this work, the addition of 0.5 mol% Fe 2 O 3 in GDC diffusion barrier layer as sintering aid is studied. The symmetrical cell and the fuel cell are fabricated by hot-pressing, co-sintering and screen-printing technologies. It is found that the addition of Fe 2 O 3 can make GDC barrier layer denser at a reduced sintering temperature of 1250 °C and prevent diffusion of Sr to form ionic insulating interface between YSZ (Y 2 O 3 stabilized ZrO 2) and La 0.6 Sr 0.4 Co 0.8 Fe 0.2 O 3-δ (LSCF). The fuel cell based on the GDC-Fe 2 O 3 barrier layer achieves better maximum power density of 0.89 W cm−2 at 800 °C than that of 0.68 W cm−2 without Fe 2 O 3 addition. No obvious degradation was observed on fuel cell based on the GDC-Fe 2 O 3 diffusion barrier layer after a stability test at 750 °C for 100 h under 0.75 V and the thermal cycling between 750 and 400 °C. The results indicate that the addition of Fe 2 O 3 sintering aid in GDC diffusion barrier layer can promote the densification of GDC and exhibit good long-term stability and thermal cycle stability. [Display omitted] • Anode support SOFC was successfully fabricated by tape casting, hot-pressing and co-sintering technology. • A dense Gd 0.1 Ce 0.9 O 1.95 (GDC) layer was obtained at 1250 °C with Fe 2 O 3 sintering aid. • The maximum power density at 800 °C of the cell is improved by 24% through addition of Fe 2 O 3 to the GDC layer. • The fuel cell based on the GDC-Fe 2 O 3 barrier layer is demonstrated to have good durability and thermal cycling stability. [ABSTRACT FROM AUTHOR]

Reversible solid oxide cells (RSOCs) are clean and effective electrochemical conversion devices that require highly active electrodes and stable electrochemical performance for the practical application. Herein, we investigate a series of La 0.8-x Bi x Sr 0.2 Ni 0.2 Fe 0.8 O 3-δ (LBSNF-x, x = 0.0, 0.05, 0.1, 0.15) oxides as the potential oxygen electrode material for RSOCs. The properties of electrical conductivity, thermal expansion coefficient, and chemical compatibility with the Ce 0.9 Gd 0.1 O 1.95 (GDC) barrier layer of LBSNF-x oxides are evaluated. When LBSNF-0.1 and GDC forms a composite oxygen electrode with the ratio of 7:3, it shows the lowest polarization resistance with fastest oxygen reduction reaction activity in the symmetrical cell test. Then the cell with the configuration of Ni-YSZ/YSZ/GDC/LBSNF-0.1-GDC was prepared and evaluated both in fuel cell (FC) and electrolysis cell (EC) mode. The maximum power density of 824 mW cm−2 is obtained at 800 °C in FC mode, and current density of 1.20 A cm−2 is achieved under 50% steam content at 1.3 V in EC mode. Additionally, the cell exhibits good stability both in FC and EC mode after 80 h test at 700 °C. The results of this work provide a strong support for application of the LBSNF-0.1-GDC oxygen electrode for reversible solid oxide cells. • La 0.8-x Bi x Sr 0.2 Ni 0.2 Fe 0.8 O 3-δ (LBSNF-x, x = 0.0, 0.05, 0.1, 0.15) perovskite oxides are synthesized and characterized. • Peak power density of 824 mW/cm2 is obtained at 800 °C for Ni-YSZ/YSZ/GDC/LBSNF-0.1-GDC cell. • The cell exhibits a significant electrolysis current density of 1.20 A/cm2 at 800 °C with 50% H 2 O at 1.3 V. • The cell shows good reversible stability in both fuel cell and electrolysis mode at 700 °C during 80 h test. [ABSTRACT FROM AUTHOR]

Developmental patterning is essential for regulating cellular events such as axial patterning, segmentation, tissue formation, and organ size determination during embryogenesis. Understanding the patterning mechanisms remains a central challenge and fundamental interest in developmental biology. Ion-channel-regulated bioelectric signals have emerged as a player of the patterning mechanism, which may interact with morphogens. Evidence from multiple model organisms reveals the roles of bioelectricity in embryonic development, regeneration, and cancers. The Zebrafish model is the second most used vertebrate model, next to the mouse model. The zebrafish model has great potential for elucidating the functions of bioelectricity due to many advantages such as external development, transparent early embryogenesis, and tractable genetics. Here, we review genetic evidence from zebrafish mutants with fin-size and pigment changes related to ion channels and bioelectricity. In addition, we review the cell membrane voltage reporting and chemogenetic tools that have already been used or have great potential to be implemented in zebrafish models. Finally, new perspectives and opportunities for bioelectricity research with zebrafish are discussed. [ABSTRACT FROM AUTHOR]

In this paper, the magnetic immunity model of STT-MRAM is established. The influence of the external magnetic field on the effective energy barrier of STT-MRAM is investigated, which is the crucial issue to influence the reliability of STT-MRAM cells in the standby, active read and active write modes. The influence factors on the magnetic immunity of STT-MRAM array are also discussed in the paper, such as the electrode, package material, insert layer and array spacing, etc. Moreover, the magnetic shield models in the BGA and QFP packages are designed and analyzed for the enhancement of the magnetic immunity of STT-MRAM, whose shielding efficiency is up to 98.2%. [ABSTRACT FROM AUTHOR]

In the paper, novel multi-bit parallel pipeline circuit design of STT-MRAM is proposed to improve the read and write efficiency. The shift register is utilized to change the series data into the parallel ones. Combined with the corresponding sense amplifier (SA) circuit and the write drive circuit, 4-bit data can be read or written in parallel in single cycle. With the 32 Kbit data test, the efficiencies of the read and the write operations of the proposed pipeline circuit are increased by 72.3% and 74.4%, separately, with the comparison of the incumbent series operations. The proposed strategy has potential application in the embedded high speed STT-MRAM. [ABSTRACT FROM AUTHOR]

With CMOS process developing, the Static Random Access Memory (SRAM) suffers unavoidable degradation in terms of read and write stabilities. To optimise the memory with conventional 6-T cell in 7-nm process technology, Response Surface Method (RSM) is adopted to get the optimised relationship among the noise margin, the operating temperature, the supply voltage, the unit ratio, the pull-up ratio and the pre-charged voltage, et al. It shows that RSM approach is an effective statistical method for the optimisation of the SRAM cell, especially in the nano-scale scheme. In order to prove the superiority of the RSM approach, the noise margin variation is investigated from 90 nm to 7 nm technology nodes based on the general butterfly curves approach for the comparison. It shows that the stability of the SNM of the 6-T cell tends to be degraded with the continuous shrinkage of the process nodes. The RSM approach is demonstrated to be an effective way for the optimisation of the SRAM cell in single-digit nanometre node. [ABSTRACT FROM AUTHOR]

A fast writing strategy of spin transfer torque (STT) magnetic random access memory (STT-MRAM) combined with pipeline architecture and early write termination (EWT) technology is proposed in this article. Both the writing speed and the writing power consumption of STT-MRAM are optimized. First, based on the proposed pipeline structure, the writing operation can be conducted within a single clock cycle, much decreasing the writing time. Second, the EWT technology is adopted in the writing operation. In the traditional operation of STT-MRAM, the same data are repeatedly written to the memory cell, which wastes the writing power consumption and the writing operation time. In this article, combined with the EWT technology and the pipeline architecture, the unnecessary writing power is reduced by 92.8%, while the necessary writing power is increased by 19.8%. Taking 32 kb data for the writing operation, the operation speed of the new writing strategy is increased by 67.4% compared with the incumbent writing technology. The proposed strategy has potential application in the embedded STT-MRAM acting as cache memory in the computer system. [ABSTRACT FROM AUTHOR]

To solve the problem of low-frequency noise in aircraft cabin, a Helmholtz periodic structure with double labyrinth tubes was proposed in this paper. The design of labyrinth tubes greatly increases the length of tubes of Helmholtz resonator, reducing the lower limit of low-frequency band gap. The design of double opening tubes can increase the region of local resonance of the phononic crystal, therefore, the number of low-frequency band gaps increases. Firstly, the band structure and sound insulation characteristics of the structure in the frequency range from 0 Hz to 500 Hz were characterized by finite element method (FEM). It is found that the structure has multiple complete low-frequency band gaps in the frequency range from 0 Hz to 500 Hz, showing an excellent low-frequency sound insulation characteristic. Secondly, to reveal the mechanism of band gap, the equivalent circuit model was established by the method of electro-acoustic analogy. Finally, the influence factors of band gaps were analyzed by FEM and equivalent model. It is found that increasing the length of the tubes can effectively reduce the lower limit of the band gap, and a smaller lattice constant is beneficial to widen the band gap. The research in this paper further explores the influence of phononic crystal structure design on band gap and provides a new method for low-frequency noise reduction of aircraft cabin. [ABSTRACT FROM AUTHOR]

A micromachined thermopile infrared sensor is designed and optimized with high detective sensitivity in the article. A matched chopper operational amplifier with good linearity is implemented for signal processing. Optimizations of the sensor’s structure are proposed by the adjustment of the length of the thermocouple pairs and the filling of the back-etched cavity based on the adopted thermocouple materials. A passivation layer is implemented to minimize the flicker noise of the sensor. Based on the requirement of the optimized thermopile sensor system, both the flicker noise and the low-frequency noise of the system are suppressed for achieving high sensitivity. The chopper operational amplifier circuit with a single-ended closed-loop diagram is specifically designed for signal amplification and noise suppression. The fabricated device shows improved characterizations, with the responsivity of 182.72 V/W, detectivity of $2.47\times 10^{{8}}$ cmHz1/2/W, time constant of 10 ms, and total resistance of 270 $\text{k}\Omega $. The sensitivity of the designed system, including the sensor and the amplifier, is about 15 mV/°C, when the gain is 40 dB and the sensor-target distance is 3 cm. The system shows wide applications in the fields of noncontact temperature measurement and other special applications. [ABSTRACT FROM AUTHOR]

Vismodegib, a Smoothened antagonist, is clinically approved for treatment of human basal cell carcinoma (BCC), in the clinical trials of medulloblastoma (MB) and other cancers. However, a significant proportion of these tumors fail to respond to Vismodegib after a period of treatment. Here, we find that AMPK agonists, A769662, and Metformin, can inhibit GLI1 activity and synergize with Vismodegib to suppress MB cell growth invitro and invivo. Furthermore, combination of AMPK agonists with Vismodegib is effective in overcoming Vismodegib‐resistant MB. This is the first report demonstrating that combining AMPK agonist (Metformin) and SHH pathway inhibitor (Vismodegib) confers synergy for MB treatment and provides an effective chemotherapeutic regimen that can be used to overcome resistance to Vismodegib in SHH‐driven cancers. [ABSTRACT FROM AUTHOR]

A novel CMOS hexaferrite circulator with a Y-junction structure is designed and fabricated, which is compatible with standard CMOS technology. The spin-coating approach is adopted during the fabrication, in which the photoresist is mixed with nano-hexaferrite powder for preparation of a magnetic thin film in the device. Compared with the traditional circulator with an external permanent magnet for operation, the novel circulator can utilize the spin-coating magnetic film and is compatible with CMOS technology. The remanent magnetization of the adopted hexaferrite thin film can provide the required magnetic field for reciprocity properties. The optimization of impedance matching and the improvements in the related parameters are demonstrated on the novel CMOS circulator. The CMOS circulator exhibits the merits of small volume and easy integration while keeping its promising non-reciprocity properties. The fabrication is conducted based on the standard 180-nm CMOS technology. S-parameter measurements on the circulator show that the device has an isolation of 20 dB over 520 MHz bandwidth at 26.2 GHz. The minimum insertion loss is 1.81 dB. The novel CMOS-compatible circulator has potential application in 5G wireless communication systems. [ABSTRACT FROM AUTHOR]

Y-type non-fullerene acceptors with outer bulky branched side chains and weaker electron withdrawing end groups were designed for polymer solar cells. A decent PCE of 15.03% was achieved for D18:BTP-TCl binary device, which was further improved to 19.15% by adding BTP-TCl to the D18:BTP-eC9 host blend. [Display omitted] • Y-typed small molecular acceptors were synthesized with upshifted LUMO levels. • D18:BTP-TCl achieved a decent PCE of 15.03 % with a high V oc of 0.986 V. • The ternary device of D18:BTP-eC9:BTP-TCl achieved a champion PCE of 19.15%. • Simultaneous enhancement of J sc and V oc of PSCs was achieved. Simultaneously enhancing the short-circuit current density (J sc) and open-circuit voltage (V oc) of current state-of-the-art polymer solar cells (PSCs) containing wide bandgap polymers as donors and Y6 derivatives as acceptors is of great challenge but essential for further improvement of the photovoltaic performances. In this work, two Y-type non-fullerene acceptors of BTP-T and BTP-TCl were designed and successfully synthesized with relatively weak electron-accepting thiophene based end groups, where blue-shifted absorption and upshifted LUMO energy levels were achieved to fill the well-known absorption gap at 700 nm of typical binary devices based Y-type molecules and rise the output voltage, respectively. Simultaneously increased J sc and V oc were achieved in ternary blend devices containing D18:BTP-eC9:BTP-TCl with a significantly improved PCE up to 19.15 %, which is over 7 % increase compared to the binary device. Our results illustrated the great potential of rational design of Y6 derivatives for constructing ternary PSCs to improve their performances. [ABSTRACT FROM AUTHOR]

The femtosecond pump-probe technique was used to study the carrier dynamics of amorphous Ge2Sb2Te5 films. With carrier density at around 1020-1021 cm-3, carriers were excited within 1 ps and recovered to the initial state for less than 3 ns. On the picosecond time scale, the carrier relaxation consists of two components: a fast process within 5 ps and a slow process after 5 ps. The relaxation time of the fast component is a function of carrier density, which increases from 1.9 to 4.3 ps for the carrier density changing from 9.7×1020 cm-3 to 3.1×1021 cm-3. A possible interpretation of the relaxation processes is elucidated. In the first 5 ps the relaxation process is dominated by an intraband carrier relaxation and the carrier trapping. It is followed by a recombination process of trapped carriers at later delay time. [ABSTRACT FROM AUTHOR]

Abstract Higher manganese silicides (HMS) are deemed as particularly promising p-type thermoelectric materials. Apart from considerations in the materials available, the difficulty in converting them into engineering devices also limits thermoelectric applications. Atmospheric plasma spraying, as a flexible and cost-effective manufacturing process, was employed to produce thermoelectric films. In this study, HMS films were deposited using atmospheric plasma spray under controlled spraying power with different thermal exposures. The as-sprayed HMS films were characterized not only for phase and microstructure, but also for temperature dependent electrical conductivity and Seebeck coefficient. The power factor was calculated to assess the effect of spraying power on thermoelectric performance. The results show that the spraying power not only affects the melt state of the HMS particles, which leads to the variation of the microstructure of the films, but also its stoichiometry associated with phase transformation during spraying process. The maximum power factor value of 156.90 μW m−1 K−2 was acquired at 500 °C for HMS film deposited with the lowest spraying power. The results provide a large-scale fabrication method to improve the potential applicability of thermoelectric films. Highlights • P-type higher manganese silicides films were successfully deposited by atmospheric plasma spray. • The main factor that influences the thermoelectric performance is the Mn evaporation. • Thermoelectric film with the power factor value of 156.90 μW m-1 K-2 was deposited at spraying power of 24 kW. [ABSTRACT FROM AUTHOR]

Three π-conjugated small molecules (SMs) with D(π-A-Ar) 2 molecular frameworks are designed and synthesized as the donor materials in organic solar cells (OSCs). Containing tetrafluorobenzene (TFB) as central donor (D) core, thiophene as π-bridge, 2-octylthiophene (T) as terminal (Ar) unit, as well as the different arm of acceptor (A) units, pyridine-diketopyrrolopyrrole (PyDPP), thiophene-diketopyrrolopyrrole (TDPP) and isoindigo (IID), namely DTTFB(PyDPP-T) 2 , DTTFB(TDPP-T) 2 and DTTFB(IID-T) 2 , respectively. The impacts of the different acceptor arms combined with the TFB core on the optical absorption, electrochemical property, hole mobility, film morphology, and solar cell performance were studied thoroughly. As a result, these SMs presented various light absorption properties, electrochemical performances, and hole mobilities, which are helpful to the optimization of short-circuit current ( J sc ), open-circuit voltage ( V oc ) and fill factor (FF) properties, respectively. Especially, the DTTFB(TDPP-T) 2 showed a relatively lower optical band gap of 1.53 eV, and also showed the best coplanarity among the three SMs, which help it to get a higher J sc of 12.44 mA cm −2 and a higher FF of 59.50%, and resulting in obtaining a best power conversion efficiency (PCE) of 5.15% in the DTTFB(TDPP-T) 2 /PC 71 BM-based cells, which is about 2.8 and 1.6 times higher than that of DTTFB(PyDPP-T) 2 /PC 71 BM and DTTFB(IID-T) 2 /PC 71 BM based cells, respectively. Obviously, introducing different acceptor units as arms onto the D(π-A-Ar) type SMs could be a promising strategy for designing high-performance TFB-based linear molecular donor materials. [ABSTRACT FROM AUTHOR]

The air electrode with strontium and cobalt elements has the elemental diffusion or delamination issue on the air electrode/electrolyte interface in reversible protonic ceramic cells (RPCCs). Hence the development of strontium and cobalt-free triple conducting (H+/O2-/e-) air electrodes with high electrochemical activity and stability is urgent. Here, we report a strontium and cobalt-free Ba 0.8 Ca 0.2 FeO 3-δ (BCF82) air electrode with high catalytic activity and electrochemical stability for oxygen reduction/evolution reactions. A RPCC with the BCF82 air electrode shows a high peak power density of 1.14 W cm−2 in the fuel cell mode and a current density of 3.49 A cm−2 under 1.3 V in the electrolysis mode at 700 °C. Furthermore, the cell demonstrates suitable stability in the fuel cell, electrolysis and reversible modes at 600 °C for hundreds of hours without elemental segregation and delamination issue. This work offers an efficient approach to develop low-cost and durable air electrodes for RPCCs. [Display omitted] • Ba 0.8 Ca 0.2 FeO 3-δ (BCF82) shows good steam adsorption and ion diffusion capacities. • BCF82 air electrode shows high activity and stability. • Reversible cells with the BCF82 air electrode show suitable performance and stability. [ABSTRACT FROM AUTHOR]

Abstract: Two wide bandgap star‐shaped small molecular acceptors, para‐TrBRCN and meta‐TrBRCN, are synthesized for efficient nonfullerene polymer solar cells (PSCs). The tiny structural variation by just changing the linkage positions affects largely the inherent properties of the resulting molecules. Both molecules have a nonplanar 3D structure, which can prevent the excessively aggregation to realize the optimized morphology and ideal domain size in their active blends. Compared to para‐TrBRCN, meta‐TrBRCN exhibits the smaller distortions between the truxene skeleton and the benzothiadiazole units, which would also lead to the enhanced π–π stacking and charge transfer. When blending with PTB7‐Th, high power conversion efficiencies (PCEs) of 10.15% and 8.28% are obtained for meta‐TrBRCN and para‐TrBRCN devices, respectively. To make up the weak absorption of above binary active blend in the longer wavelength region and increase the whole device performance further, low bandgap 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone)‐5,5,11,11‐tetrakis(4‐hexylthienyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′]‐dithiophene (ITIC‐Th) is added as the second acceptor material to fabricate ternary blend PSCs. After adding 20 wt% of ITIC‐Th, the resulting devices exhibit the well‐balanced optical absorption and fine‐tuned morphology, giving rise to the significantly improved PCE of 11.40% with much higher Jsc of 18.25 mA cm−2 and fill factor of 70.2%. [ABSTRACT FROM AUTHOR]

Abstract: In this work, four donor (D)–acceptor (A) copolymers based on benzodithiophene (BDT) and benzothiadiazole (BT) with different alkylthiolated and/or fluorinated side chains are developed for efficient fullerene and nonfullerene polymer solar cells (PSCs). The synergistic effect of sulfuration and fluorination on the optical absorption, energy level, crystallinity, carrier mobility, blend morphology, and photovoltaic performance is investigated systematically. By incorporating sulfur atoms onto the side chains, a little blueshifted but significantly increased absorption can be obtained for PBDTS‐FBT compared to PBDT‐FBT. On the other side, a little more blueshifted but much stronger absorption and much lower‐lying highest occupied molecular orbital (HOMO) level can be realized for PBDTF‐FBT when introducing fluorine atoms instead of sulfur atoms. With the combination of both fluorination and sulfuration strategies, PBDTS‐FBT exhibits the best absorption ability, lowest HOMO energy level, and highest crystallinity, which make PBDTSF‐FBT devices show the highest power conversion efficiency (PCE) of 10.69% in fullerene PSCs and 11.66% in nonfullerene PSCs. The PCE of 11.66% is the best value for PSCs based on BT‐containing copolymer donors reported so far. The results indicate that fluorination and sulfuration have a synergistically positive effect on the performance of D–A photovoltaic copolymers and their solar cell devices. [ABSTRACT FROM AUTHOR]

Abstract: In this work, four donor (D)–acceptor (A) copolymers based on benzodithiophene (BDT) and benzothiadiazole (BT) with different alkylthiolated and/or fluorinated side chains are developed for efficient fullerene and nonfullerene polymer solar cells (PSCs). The synergistic effect of sulfuration and fluorination on the optical absorption, energy level, crystallinity, carrier mobility, blend morphology, and photovoltaic performance is investigated systematically. By incorporating sulfur atoms onto the side chains, a little blueshifted but significantly increased absorption can be obtained for PBDTS‐FBT compared to PBDT‐FBT. On the other side, a little more blueshifted but much stronger absorption and much lower‐lying highest occupied molecular orbital (HOMO) level can be realized for PBDTF‐FBT when introducing fluorine atoms instead of sulfur atoms. With the combination of both fluorination and sulfuration strategies, PBDTS‐FBT exhibits the best absorption ability, lowest HOMO energy level, and highest crystallinity, which make PBDTSF‐FBT devices show the highest power conversion efficiency (PCE) of 10.69% in fullerene PSCs and 11.66% in nonfullerene PSCs. The PCE of 11.66% is the best value for PSCs based on BT‐containing copolymer donors reported so far. The results indicate that fluorination and sulfuration have a synergistically positive effect on the performance of D–A photovoltaic copolymers and their solar cell devices. [ABSTRACT FROM AUTHOR]

In this study, we report a novel medium-entropy perovskite oxide of La 0.7 Sr 0.3 Co 0.25 Fe 0.25 Ni 0.25 Mn 0.25 O 3-δ (LSCFNM73) with high constitutive entropy (S config) as the cathode material of intermediate temperature solid oxide fuel cells (IT-SOFCs). The intrinsic properties of phase structure, electrical conductivity, thermal expansion and oxygen adsorption capacity of La 1-x Sr x Co 0.25 Fe 0.25 Ni 0.25 Mn 0.25 O 3-δ (LSCFNM, x = 0, 0.1, 0.2, 0.3) oxides are evaluated in detail. The LSCFNM73 oxide exhibits the maximum electrical conductivity of 464 S cm−1 at 800 °C and a relatively lower thermal expansion coefficient (TEC) of 15.34 × 10−6 K−1, which is selected as the propriate cathode composition. The B-site of LSCFNM73 contains four elements which can increase the configuration entropy. Additionally, NiO-Yttria stabilized zirconia (YSZ) supported fuel cell is fabricated by tape casting, hot pressing-lamination, co-sintering and screen printing technologies. The fuel cell demonstrates a maximum power density of 1088 mW cm2 at 800 °C, and excellent stability at 750 °C under 0.75V in 120 h and 10 times thermal cycling between 750 °C and 400 °C. Therefore, the medium-entropy LSCFNM73 oxide can be applied in IT-SOFCs as a competitive cathode material. • Medium-entropy oxides of La 1-x Sr x Co 0.25 Fe 0.25 Ni 0.25 Mn 0.25 O 3-δ (LSCFNM, x = 0, 0.1, 0.2, 0.3) are synthesized and evaluated. • B-site of ABO 3 contains four elements can increase the configuration entropy. • The maximum power density of fuel cell at 800 °C is 1088 mW cm−2. • The single fuel cell shows good stability in 120 h at 750 °C and well thermal cycling stability after 10 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • The oxygen permeation performance was tested by a novel electrochemical method based on limiting current instead of gas chromatography at the first time. • A "porous-transition-dense" three-layer of porous 3YSZ/dense 3YSZ-La 0.8−x Bi x Sr 0.2 FeO 3-δ /dense La 0.8−x Bi x Sr 0.2 FeO 3-δ membrane was successfully fabricated by tape casting, hot-pressing and co-sintering technology. • The best oxygen permeability of La 0.4 Bi 0.4 Sr 0.2 FeO 3-δ membrane could reach 1.13 mL min−1 cm−2 at 800 °C with 20% oxygen partial pressure. • The La 0.4 Bi 0.4 Sr 0.2 FeO 3-δ membrane demonstrated excellent long-term stability and thermal cycle stability at 800 °C under 1.6 V for 150 h and subsequent 11 times thermal cycling between 700 °C and 800 °C. Ceramic oxygen permeable membranes (COPMs) have attracted attention as a "next generation" technology for oxygen separation. However, developing new oxygen permeable membrane materials with high oxygen permeability at an intermediate operating temperature is still challengeable. In this work, a series of perovskite La 0.8-x Bi x Sr 0.2 FeO 3-δ (LBSF, x = 0.0, 0.2, 0.3 and 0.4) oxides were synthesized and used as the oxygen permeation membrane materials. The phase structure, electrical conductivity, chemical compatibility with 3 mol% yttria-stabilized zirconia (3YSZ), O 2 temperature programmed desorption (O 2 -TPD) have been evaluated. An asymmetric three-layer structure with "porous-transition-dense" was developed by tape casting, hot-pressing and co-sintering technology. The membrane consists of a porous 3YSZ support layer, a 3YSZ-LBSF transition layer and a dense LBSF functional layer. The oxygen permeability was tested by a new designed electrochemical device based on the limit current method. The best oxygen permeability was found in the composition of La 0.4 Bi 0.4 Sr 0.2 FeO 3-δ measured at an intermediate temperature of 800 °C with 20% oxygen partial pressure, which could reach 1.13 mL min−1 cm−2. No obvious degradation was observed on the three-layers La 0.4 Bi 0.4 Sr 0.2 FeO 3-δ membrane after a stability test at 800 °C for 150 h under 1.6 V and subsequent 11 times thermal cycling between 700 °C and 800 °C. The membrane exhibited excellent long-term stability and thermal cycling stability. [ABSTRACT FROM AUTHOR]

Additive manufacturing based on gas metal arc welding (GMAW) is gaining increasing popularity as the process allows fabrication of fully dense parts with high material efficiencies and deposition rates. This paper aims at studying forming characteristics of multi-layer single-pass parts. Influences of arc current, deposit velocity, and heat input on layer formation were analyzed by using a passive vision sensor. Based on the results, the arc current has the greatest effect on the forming appearance, and a better understanding of the forming characteristics and process specification interval in multi-layer single-pass GMAW-based additive manufacturing can be obtained. Some newly improved GMAW methods were considered to improve deposition rates in multi-layer single-pass additive manufacturing process. [ABSTRACT FROM AUTHOR]

An investigation of the influence of the magnetic field induced by electrostatic discharge (ESD) current on magnetic tunnel junction (MTJ) device is presented in the paper. The transient magnetic field generated by the ESD current is not considered in the traditional CMOS ESD protection strategy, which may be a reason of the degradation of the performance and the robustness of STT-MRAM. An ESD protection circuit of STT-MRAM is proposed in the paper, including the diode-based ESD devices, the filter circuit and the power clamp. Based on the waveform analysis of the three ESD standard test models, including HBM, MM and CDM, a filter circuit is added in the ESD device to decrease the influence of the high frequency components on the magnetic device. The diode-based ESD devices are integrated in the ESD structure, which is used for the ESD window of STT-MRAM for its low operating voltage. Based on the operation mechanism of the STT-MRAM, its ESD window allows a low operating voltage, thus the diode-based devices are chosen to be integrated in the ESD device. The distribution and magnitude of the magnetic field are studied in the paper. The results show that the ESD protection circuit of STT-MRAM can effectively suppress the magnetic field generated by the ESD current, hence increasing the stability of STT-MRAM. Under the influence of the HBM, MM and CDM events, the ESD disturbance probability of the MTJ device are 2.0 × 10−12, 5.8 × 10−9 and 1.1 × 10−12 respectively. The influence of the memory density and the distance between pads and memory array are also investigated in this paper. The ESD protection strategy proposed in the paper can be adopted for the future high performance STT-MRAM. • The data stored in the MTJs can be destroyed by the induced magnetic field of ESD. • The influence of different ESD standard test models on MTJs have been studied. • The magnetic field and duration time of ESD events cause the magnetic reversal. [ABSTRACT FROM AUTHOR]

Video Action Recognition (ViAR) aims to identify the category of the human action observed in a given video. With the advent of Deep Learning (DL) techniques, noticeable performance breakthroughs have been achieved in this study. However, the success of most existing DL-based ViAR methods heavily relies on the existence of a large amount of annotated data, i.e. , videos with corresponding action categories. In practice, obtaining such a desired number of annotations is often difficult due to expensive labeling costs, which may lead to significant performance degradation for these methods. To address this issue, we propose an end-to-end semi-supervised Differentiated Auxiliary guided Network (DANet) to best use a few annotated videos. Except for the common supervised learning on a few annotated videos, the DANet also involves the knowledge of multiple pre-trained auxiliary networks to optimize the ViAR network in a self-supervised way on the unannotated data by removing the annotations. Considering the tight connection between video action recognition and classical static image-based visual tasks, the abundant knowledge from the pre-trained static image-based models can be used for training the ViAR model. Specifically, the DANet is a two-branch architecture, which includes a target branch of the ViAR network, and an auxiliary branch of multiple auxiliary networks (i.e. , referring to diverse off-the-shelf models of relevant image tasks). Given a limited number of annotated videos, we train the target ViAR network end-to-end in a semi-supervised way, namely, with both the supervised cross-entropy loss on annotated videos, and the per-auxiliary weighted self-supervised contrastive losses on the same videos but without using annotations. Besides, we further explore different weighted guidance of the auxiliary networks to the ViAR network to better reflect different relationships between the image-based models and the ViAR model. Finally, we conduct extensive experiments on several popular action recognition benchmarks in comparison with existing state-of-the-art methods, and the experimental results demonstrate the superiority of DANet over most of the compared methods. In particular, the DANet obviously suppresses state-of-the-art ViAR methods even with very fewer annotated videos. [ABSTRACT FROM AUTHOR]

Abstract: A passive vision sensor system has been developed to monitor the nozzle to the top surface distance (NTSD) in layer additive manufacturing (LAM) using gas metal arc welding (GMAW). The deviations in the NTSD are compensated by the movement of the working flat, and the adjustment of the deposition rate on next deposition layer. After simplification of the controlled process into a linear system, an adaptive control system has been designed to keep the NTSD constant. The effectiveness of the controller is evaluated through deposition of single-bead multi-layer walls, and the experimental results confirm that the process stability can be improved when applying the developed controller. [Copyright &y& Elsevier]

Background: Our previous studies show that microRNA-92a (miR-92a) is overexpressed in colorectal cancer (CRC) and is thought to be correlated with the development of the cancer. However, its biological role in CRC remains poorly understood. Aims: The aim of the study was to determine the role of miR-92a and to elucidate its regulatory mechanism in CRC. Methods: The expression levels of miR-92a and phosphatase and tensin homologue (PTEN) were detected by qRT-PCR and western blot. MTT, migration and invasion assays were used to examine the proliferation, migration and invasion of pre-miR-92a transfected SW480 cells, and a mouse model was used to investigate tumorigenesis. In addition, the regulation of PTEN by miR-92a was evaluated by qRT-PCR, western blot and luciferase reporter assays. Results: The expression of miR-92a was significantly up-regulated in the tissues of CRC patients with lymph node metastasis. The ectopic expression of miR-92a enhanced CRC cell proliferation, migration and invasion. Similar results were found in xenograft assay performed in nude mice. Up-regulation of miR-92a induced EMT in CRC cells. There was an inverse correlation between the levels of miR-92a and PTEN in CRC tissues. The overexpression of miR-92a in CRC cells decreased PTEN expression at the translational level, and decreased PTEN-driven luciferase-reporter activity. Conclusions: Our results demonstrated that miR-92a induced EMT and regulated cell growth, migration and invasion in the SW480 cells, at least partially, via suppression of PTEN expression. MiR-92a may serve as a novel therapeutic target in colorectal cancer. [ABSTRACT FROM AUTHOR]

During the layered deposition of forming metallic parts with robotic gas metal arc welding, the geometry of a single weld bead plays an important role in determining the layer thickness and dimensional precision of the deposited layer. This paper addresses prediction of welding process parameters for the expected bead geometry with accordance to the adaptive slicing process in rapid manufacturing. The correlation between the process parameters and the bead geometry was established by applying an artificial neural network. A central composite design was employed to conduct experiments for collecting input-output data. A closed-loop iteration system, consisting of a forward model for predicting bead size and a reverse model for forecasting process parameters, was proposed to predict the optimal welding parameters for the desired bead geometry. The results show that the prediction of process parameters obtained from the designed closed-loop iteration system confirms the feasibility of this system in terms of applicability and automation in the additive manufacturing process. [ABSTRACT FROM AUTHOR]

The identification of cancer drivers is a major goal of current cancer research. Finding driver genes within large chromosomal events is especially challenging because such alterations encompass many genes. Previously, we demonstrated that zebrafish malignant peripheral nerve sheath tumors (MPNSTs) are highly aneuploid, much like human tumors. In this study, we examined 147 zebrafish MPNSTs by massively parallel sequencing and identified both large and focal copy number alterations (CNAs). Given the low degree of conserved synteny between fish and mammals, we reasoned that comparative analyses of CNAs from fish versus human MPNSTs would enable elimination of a large proportion of passenger mutations, especially on large CNAs. We established a list of orthologous genes between human and zebrafish, which includes approximately two-thirds of human protein-coding genes. For the subset of these genes found in human MPNST CNAs, only one quarter of their orthologues were co-gained or co-lost in zebrafish, dramatically narrowing the list of candidate cancer drivers for both focal and large CNAs. We conclude that zebrafish-human comparative analysis represents a powerful, and broadly applicable, tool to enrich for evolutionarily conserved cancer drivers. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the feasibility and safety of transareola single-site endoscopic thyroidectomy. Subjects and Methods: Twenty-eight patients with thyroid nodules were involved in this study. An incision was cut on a single areola, and a laparoendoscope apparatus and an operating apparatus were implanted. The thyroid gland was exposed using the neck suture suspension technique, and the damaged thyroid gland was removed with an ultrasonic scalpel. The operation time, intraoperative bleeding volume, postoperative pain score, and cosmetic satisfaction score were calculated. Results: Unilateral subtotal thyroidectomy was performed in 12 cases, unilateral partial thyroidectomy in 14 cases, and bilateral partial thyroidectomy in 2 cases. For the former 14 cases, the operation time was 145-205 minutes, with a mean duration of 170 minutes; the operation time ranged from 125 to 150 minutes, with a mean of 135 minutes, for the latter 14 cases. The intraoperative bleeding volume was 15-40 mL, with a mean of 25 mL. The total postoperative wound drainage was 80-135 mL, with a mean of 110 mL. The drainage tube was removed 3-4 days after surgery. The visual analog scale score was 1-5 at 24 hours postoperatively, with a mean score of 3.10. Postoperative pathological examination diagnosed thyroid adenoma in 11 cases and nodular goiter in 17 cases. Conclusions: Transareola single-site endoscopic thyroidectomy is feasible and safe and has the advantages of a covert incision, small subcutaneous separation area, and high cosmetic satisfaction. The operation time shortens with the increasing number of patients undergoing operations. [ABSTRACT FROM AUTHOR]

• Planar propeller-like PDIs were synthesized by noncovalent interactions. • Thiophene and nitrogen annulations were applied to PDI arms with increasing photovoltaic property. • Fine tuning the noncovalent interaction strength promoted PCEs reaching 10.52%. The development of non-fullerene small molecule acceptors enabled fast increasing top power conversion efficiency of polymer solar cells (PSCs). Perylene diimide (PDI) derivatives are among the most promising non-fullerene small molecule acceptors for their relatively straightforward accessible PDI chromophores readily deliver high electron mobility and intensive photon absorption in visible range. In this work, we demonstrated noncovalent interaction as a third strategy of connecting the PDI arms to the center core of propeller-like PDI derivatives other than flexible and all fused linkages through designing and synthesizing two novel PDI derivatives. Thiophene-annulated PDI arms were connected to a small electron withdrawing 1,3,5-triazine center core where N⋯S noncovalent conformational locks restricted the distortion of molecules. Fine tuning of the aggregation tendency of the PDI derivative by introducing N-annulation at the outer bay position of each PDI arms which achieved an outstanding power conversion efficiency reaching 10.52%, which is one of the top PCEs of PDI-based PSCs. [ABSTRACT FROM AUTHOR]

Previous studies on the synchronization behaviors of neuronal networks were constructed by integer-order neuronal models. In contrast, this paper proposes that the above topics of symmetrical neuronal networks are constructed by fractional-order Hindmarsh–Rose (HR) models under electromagnetic radiation. They are then investigated numerically. From the research results, several novel phenomena and conclusions can be drawn. First, for the two symmetrical coupled neuronal models, the synchronization degree is influenced by the fractional-order q and the feedback gain parameter k 1 . In addition, the fractional-order or the parameter k 1 can induce the synchronization transitions of bursting synchronization, perfect synchronization and phase synchronization. For perfect synchronization, the synchronization transitions of chaotic synchronization and periodic synchronization induced by q or parameter k 1 are also observed. In particular, when the fractional-order is small, such as 0.6, the synchronization transitions are more complex. Then, for a symmetrical ring neuronal network under electromagnetic radiation, with the change in the memory-conductance parameter β of the electromagnetic radiation, k 1 and q , compared with the fractional-order HR model's ring neuronal network without electromagnetic radiation, the synchronization behaviors are more complex. According to the simulation results, the influence of k 1 and q can be summarized into three cases: β > 0.02 , − 0.06 < β < 0.02 and β < − 0.06 . The influence rules and some interesting phenomena are investigated. [ABSTRACT FROM AUTHOR]

Abstract: Rapid manufacturing technologies have made it possible to reduce material wastes and to remanufacture valuable dies and tools. This paper focuses on reasonable utilization of materials and energies in gas metal arc welding (GMAW) for rapid manufacturing. During the weld-based additive manufacturing process, geometries of the deposited weld beads should be monitored and controlled. Using a composite filtering technique, a computer vision-sensing system was designed. Features of the weld bead image were analyzed. A corresponding image processing technology was used to extract parameters of the deposited weld beads. An on-line control of the deposited beads was realized based on a segmented neuron self-learning controller. The results show that the proposed control system is capable of keeping the deposited bead width of a thin-walled part consistent, making an efficient use of materials and energies possible. [Copyright &y& Elsevier]

Objectives: MicroRNAs regulate gene expression at the post-transcriptional level and play important roles in cancer development, progression, and metastasis. The aim of this study was to investigate the expression of miR-92a in colorectal cancer and the normal adjacent mucosa and its potential relevance to clinicopathological characteristics and patient survival. Methods: Surgical specimens of cancer tissue and adjacent normal mucosa were obtained from 82 patients with colorectal carcinomas. The relative expression levels of miR-92a mRNA in the cancer and the normal adjacent mucosa were measured by quantitative real-time reverse transcriptase polymerase chain reaction. We analyzed their correlation with tumor metastasis, clinicopathologic parameters, and clinical outcome. Results: The relative expression levels of miR-92a were significantly higher in colorectal cancer tissues than in the normal adjacent mucosa ( p < 0.001), and a high expression of miR-92a correlated with advanced clinical stage ( p = 0.025), lymph node metastases ( p = 0.015), and distant metastases ( p = 0.046). Kaplan-Meier analysis indicated that patients with high miR-92a expression had a poor overall survival ( p = 0.001). Moreover, multivariate analysis showed that increased expression of miR-92a was an independent predictor of overall survival. Conclusion: This study revealed that miR-92a overexpression was correlated with specific colorectal cancer biopathologic features, such as TNM stage, lymph node and distant metastases, and poor survival of the patients, indicating that miR-92a may serve as a molecular prognostic marker for colorectal cancer and disease progression. [ABSTRACT FROM AUTHOR]

Abstract: The twin-electrode TIG coupling arc is a new type of welding heat source, which is generated in a single welding torch that has two tungsten electrodes insulated from each other. This paper aims at determining the distribution of temperature for the coupling arc using the Fowler–Milne method under the assumption of local thermodynamic equilibrium. The influences of welding current, arc length, and distance between both electrode tips on temperature distribution of the coupling arc were analyzed. Based on the results, a better understanding of the twin-electrode TIG welding process was obtained. [Copyright &y& Elsevier]

Abstract: The complex thermal stress and residual stress distributions in the weld-based rapid prototyping process could cause large deformation and even cracking. In this paper, the thermal stress evolution, and the residual stress distribution in a single-pass multi-layer weld-based rapid prototyping are examined, and the effect of depositing directions on the residual stress and residual strain is studied by numerical simulation, after experimental verifications of the finite element model. The results show that the predicted residual stress variation trends are generally in agreement with the experimental results. The deposition of the last layer dominated the residual stress of whole component. This is due to the stress release effect of the rear layers on the fore layers. Besides, depositing directions have significant influence on the residual stress and equivalent plastic strain distributions of components, where the deposition in the reverse direction acquires the better result. [Copyright &y& Elsevier]

Abstract: The global calibration of multiple vision sensors (MVS) with non-overlapping views has been widely studied. In this paper, a novel calibration method for MVS with non-overlapping fields of view based on 1D target is presented. First, two neighboring vision sensors are selected. The rotation matrix between the two vision sensors is computed using the co-linearity property of the feature points on 1D target. Then the translation vector is computed according to the known distances between feature points on 1D target. The global calibration of all vision sensors is realized by repeating the above pair-wise calibration on different pairs of vision sensors. Due to the small volume and mobility of 1D target, the proposed global calibration method can be applied to vision sensors distributed in a large area or narrow space. Experiment results show that the RMS error of global calibration is within 0.060mm. [Copyright &y& Elsevier]

Abstract: Weld-based rapid prototyping enables the capacity of forming 3D complex parts. In rapid prototyping there exists the particular thermal cycling, being repeatedly heated at the same place, which is the basic cause of complex thermal stress. In this paper experiments are carried out to investigate the thermal characters of single-pass ten-layer deposition. Meanwhile a 3D transient heat transfer numerical simulation with temperature-dependent material properties is conducted to investigate temperature field evolution, thermal cycling character, temperature gradient and the effects of depositing directions on the thermal process of single-pass ten-layer rapid prototyping. The calculated results match the experimental measurements well. The research results show that the heat diffusion condition of molten pool becomes worse as the depositing height increases. With other parameters being constant, the heat diffusion condition can be significantly improved by optimizing the depositing directions. The heat diffusion condition of component with the same depositing directions is better than reverse directions. [ABSTRACT FROM AUTHOR]

Abstract: A preliminary investigation of tomographic reconstruction of an asymmetric arc plasma has been carried out. The objective of this work aims at reconstructing emission coefficients of a non-axisymmetric coupling arc from measured intensities by means of an algebraic reconstruction technique (ART). In order to define the optimal experimental scheme for good quality with limited views, the dependence of the reconstruction quality on three configurations (four, eight, ten projection angles) are presented and discussed via a displaced Gaussian model. Then, the emission coefficients of a free burning arc are reconstructed by the ART with the ten-view configuration and an Abel inversion, respectively, and good agreement is obtained. Finally, the emission coefficient profiles of the coupling arc are successfully achieved with the ten-view configuration. The results show that the distribution of emission coefficient for the coupling arc is different from centrosymmetric shape. The ART is perfectly suitable for reconstructing emission coefficients of the coupling arc with the ten-view configuration, proving the feasibility and utility of the ART to characterize an asymmetric arc. [ABSTRACT FROM AUTHOR]

Abstract: A miniaturized sensor for measuring carbon dioxide (CO2) gas concentration is developed based on infrared absorption. A novel space-double-beam optical probe is designed, which consists of an infrared source, an air chamber, an infrared receiving device, and two sapphire windows. The air chamber is modified by incorporating a parabolic-shaped receiving-light cone to effectively improve the signal-to-noise ratio of the sensor. Four rectangle holes are arranged around the air chamber, and diffusive sampling is adopted to collect gas into the air chamber. The infrared source works between ON and OFF states. The interference of background light is eliminated by subtracting the measured value in the ON state from the OFF state. The measurement model of the sensor is established based on the Lambert–Beer law and the working principle of the sensor. The partial least squares method is applied to calibrate the measurement model. The sensor has a volume of 80mm (L)×78mm (W)×35mm (H), a weight of 200g, a power consumption of 1.5W, and a response time of 2.5s. The experimental results show that the measurement accuracy of the sensor is 0.026% with a measurement range of 0–3% for CO2 gas concentration. [Copyright &y& Elsevier]

Abstract: A novel vision system was developed to measure the flapping motion of bilateral wings for free-flying honeybees. In the system, a geometrical optical unit, including two planar reflectors and one prism with two reflection planes, was used to image one high-speed CMOS camera into two virtual cameras. Four virtual structured-light sensors, formed by combining the two virtual cameras and two laser-sheet sources, were available to observe the flapping motion of honeybee bilateral wings. In addition, an opto-electronic attracting equipment was included to attract the free-flying honeybee and trigger the high-speed camera to capture the image sequences of the free-flying honeybee automatically. The deformation of the bilateral wings was reconstructed by the distorted light-lines projected on the surface of the wings. The measuring range of the vision system was about 25mm×20mm×20mm, and its measurement precision was smaller than 0.08mm. The kinematics parameters of the bilateral wings, such as flapping angle, lag angle, attack angle, torsion angle and camber deformation, were measured by the vision system. The virtual structured-light vision system with only one high-speed camera saves system cost, and avoids asynchronism of multiple cameras. [Copyright &y& Elsevier]

Abstract: It is extremely important to reduce and control residual angular deformation from the welding processes which has negative effects on fabrication accuracy in the manufacturing industry. A new method, asymmetrical double-sided double arc welding (ADSAW), is studied due to control residual angular distortion. Because arc distance between fore and rear torches and welding parameters are the key effective factors of angular distortions in ADSAW, but it is not clear about the effects of them on the angular distortions. In this study, experiments are carried out to investigate the thermal character and the effects of arc distance and welding parameters on the angular distortion in ADSAW. Meanwhile, a 3-D thermal elastic plastic finite element model is developed to simulate transient temperature and welding deformation with different arc distance and heat input. The simulated results are in a good agreement with the experimental measurements. The influence on welding deformation of the arc distance and heat input is investigated. In addition, the distortion mechanism and control strategy of angular distortion are clarified through numerical simulation. [Copyright &y& Elsevier]

During vertebrate embryonic development, tissue patterning and differentiation are regulated by members of multigene families. Evolutionary expansion of these families is thought to have played a role in the evolution of anatomical complexity, including the origins of new cell and tissue types. A defining feature of vertebrates is an endoskeleton, the primary components of which are cartilage and bone. The molecular control of skeletal patterning has been the subject of intensive investigation for over two decades. More recently, comparative studies of organisms at key phylogenetic positions have highlighted the importance of gene duplication in the evolutionary diversification of connective tissues. Understanding the natural histories of gene families involved in skeletogenesis is therefore central to the issue of vertebrate skeletal evolution. [Copyright &y& Elsevier]

Abstract: An algorithm for full-sky autonomous star identification is presented in this paper. Based on the radial and cyclic features, a star pattern is successfully generated, and a guide database is also established according to the generating process of the star pattern. Since the radial pattern is a kind of reliable rotation-invariant feature independent of other unreliable information, it is used for the initial match. And then the cyclic feature is adopted for the follow-up match. Meanwhile, some constraints are introduced to eliminate the redundant and wrong star pairings. In simulations, using the stars brighter than magnitude 6.0Mv and a 12×12deg field of view (FOV), the algorithm obtains an identification rate of 97.57% from the statistics of 10,000 random sensor orientations at a positional noise level of 1 pixel. [Copyright &y& Elsevier]

Abstract: A mobile coded light-based stereo vision system for measuring large 3D free surface is proposed. The system combines the technology of binocular stereo vision and multi-line structured light, which simplifies the process of finding correspondence. It can be freely moved around measured objects, and acquires local 3D data in various viewpoints. The methods of extracting light stripe are outlined. A novel approach, pyramid sub-grate projecting approach, is developed for encoding structured light. The approach can subdivide a high-density light grate into multiple sparse sub-grates. Each of the sub-grates can be effortlessly encoded by the time-multiplexing coding method. Given a point on left image, the correspondent point on right image is the intersection of coded light stripes with the same code and epipolar line. Then, the depth is estimated by triangulation. Moreover, a new registering 3D data based on a planar baseline target is detailed. The mathematic model of this registration method is given. An objective function about all parameters of rotation matrix and transmission vector being established, and those parameters can be found by Levenberg-Marquardt optimization Algorithm. However, the transmission vector is scaled by an unknown coefficient. Then the method of ascertaining the coefficient is also described. Compared with iterative closest point (ICP) algorithm, a popular registration method, the present registering method costs much less time, and is suitable for all kinds of objects. Some experimental results are presented to demonstrate the proposed technology. The results show that high-resolution 3D data of free surface has been acquired and 3D data have been perfectly registered. [Copyright &y& Elsevier]

The origin of paired appendages was a major evolutionary innovation for vertebrates, marking the first step towards fin- (and later limb-) driven locomotion. The earliest vertebrate fossils lack paired fins but have well-developed median fins, suggesting that the mechanisms of fin development were assembled first in the midline. Here we show that shark median fin development involves the same genetic programs that operate in paired appendages. Using molecular markers for different cell types, we show that median fins arise predominantly from somitic (paraxial) mesoderm, whereas paired appendages develop from lateral plate mesoderm. Expression of Hoxd and Tbx18 genes, which specify paired limb positions, also delineates the positions of median fins. Proximodistal development of median fins occurs beneath an apical ectodermal ridge, the structure that controls outgrowth of paired appendages. Each median fin bud then acquires an anteroposteriorly-nested pattern of Hoxd expression similar to that which establishes skeletal polarity in limbs. Thus, despite their different embryonic origins, paired and median fins utilize a common suite of developmental mechanisms. We extended our analysis to lampreys, which diverged from the lineage leading to gnathostomes before the origin of paired appendages, and show that their median fins also develop from somites and express orthologous Hox and Tbx genes. Together these results suggest that the molecular mechanisms for fin development originated in somitic mesoderm of early vertebrates, and that the origin of paired appendages was associated with re-deployment of these mechanisms to lateral plate mesoderm. [ABSTRACT FROM AUTHOR]

Abstract: The morphology of materials resulting from laser irradiation of the single-layer and the multilayer amorphous Ge2Sb2Te5 films using 120fs pulses at 800nm was observed using scanning electron microscopy and atomic force microscopy. For the single-layer film, the center of the irradiated spot is depression and the border is protrusion, however, for the multilayer film, the center morphology changes from a depression to a protrusion as the increase of the energy. The crystallization threshold fluence of the single-layer and the multilayer film is 22 and 23mJ/cm2, respectively. [Copyright &y& Elsevier]

Abstract: In mechanical manufacturing industry, cylindrical workpiece is one of the most commonly used type of man-made workpieces, and the verticality inspection is a very important task for guaranteeing the quality of the workpieces. In this paper, we proposed a system to inspect the verticality of cylindrical workpieces via multi-vision sensors based on structured light, which has many advantages compared with the traditional methods: fast, on-line, non-contact, flexible and remarkably more accurate. The principles and methods about how to inspect the verticality were given in details, and a real system was set up to carry out the experiments. In the system, a “sensor-unit” which consists of two stripe structured light sensors is used to address the problem of short light stripe. The experiment results indicate a high capability of the proposed system for inspecting large workpieces. [Copyright &y& Elsevier]

Abstract: To calibrate a structured light vision sensor, it is necessary to obtain at least four non-collinear feature points that fall on the light stripe plane. We propose a novel method to construct non-collinear feature points used for calibrating a structured light vision sensor with a planar calibration object. After the planar calibration object is moved freely in the range of measuring of the structured light vision sensor at least twice, all the local world coordinates of the feature points falling on the light stripe plane can be readily obtained in site. The global world coordinates of the non-collinear feature points in the local world coordinate frame can be computed through the three-dimensional (3D) camera coordinate frame. A planar calibration object is designed according to the proposed approach to provide accurate feature points. The experiments conducted on a real structured light vision sensor that consists of a camera and a single-light-stripe-plane laser projector reveal that the proposed approach has high accuracy and is practical in the vision inspection applications. The proposed approach greatly reduces the cost of the calibration equipment and simplifies the calibrating procedure. It advances structured light vision inspection one step from laboratory environments to real world use. [Copyright &y& Elsevier]

Abstract: 3D vision inspection plays an important role in industry environment. This paper focus on 3D vision inspection for internal surface based on circle structured light. The inspection system, established in this paper, consists of an Olympus industrial endoscope, a digital CCD camera, a single-circle pattern laser, a conic reflector, a transparent thin glass tube with the outer diameter of Ø4.2mm, a motorized linear motion stage, a personal computer and a few accessorial brackets. The inspection system is calibrated by a two electronic theodolites system and a plane target efficiently. Based on the mathematic model of the inspection system, the 3D shape of the internal surface is obtained from the 2D structured light stripe image on the internal surface. The experimental results show that the inspection system has a calibration accuracy of RMS x =0.032mm, RMS y =0.011mm, and RMS z =0.029mm, and a measurement accuracy of RMS x =0.041mm, RMS y =0.019mm and RMS z =0.038mm. It is proved that the inspection system is applicable to inspecting internal surface with high efficiency and accuracy. [Copyright &y& Elsevier]