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Rice grains typically contain high levels of toxic arsenic but low levels of the essential micronutrient selenium. Anthropogenic arsenic contamination of paddy soils exacerbates arsenic toxicity in rice crops resulting in substantial yield losses. Here, we report the identification of the gain-of-function arsenite tolerant 1 (astol1) mutant of rice that benefits from enhanced sulfur and selenium assimilation, arsenic tolerance, and decreased arsenic accumulation in grains. The astol1 mutation promotes the physical interaction of the chloroplast-localized O-acetylserine (thiol) lyase protein with its interaction partner serine-acetyltransferase in the cysteine synthase complex. Activation of the serine-acetyltransferase in this complex promotes the uptake of sulfate and selenium and enhances the production of cysteine, glutathione, and phytochelatins, resulting in increased tolerance and decreased translocation of arsenic to grains. Our findings uncover the pivotal sensing-function of the cysteine synthase complex in plastids for optimizing stress resilience and grain quality by regulating a fundamental macronutrient assimilation pathway., Contamination of paddy soils can lead to toxic arsenic accumulation in rice grains and low levels of the micronutrient selenium. Here the authors show that a gain of function mutant affecting an O-acetylserine (thiol) lyase enhances sulfur and selenium assimilation while reducing arsenic accumulation in grains.

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

Passive building design takes advantage of local micro-climate characteristics in site planning and analysis of house construction. In a ten-year project, we built the Orchid House with the concept of a green core to effectively reduce the energy consumption of the house. We have equipped Orchid House with smart control for passive design using an Internet of Things (IoT) solution called HouseTalk. With HouseTalk, the passive mechanisms of Orchid House are intelligently controlled to offer indoor comforts. HouseTalk integrates all sensors and actuators of the Orchid House through a Graphical User Interface (GUI). This GUI allows the users to easily and directly access all IoT devices installed in the house through graphical icon representations, and conveniently implement smart algorithms for smart home. HouseTalk dynamically adjusts the formula for HVAC operation in the closed private living area, which is appropriate for thermal control. In the open public shared space (the green core of the Orchid House), HVAC will consume much more energy, and the passive design with non-thermodynamic cycle equipment such as mechanical ventilation, evaporative cooling system, or other non-thermodynamic cycle systems are more appropriate for thermal control. HouseTalk enhances passive design by using non-thermodynamic cycle system with low energy-consumption equipment to reduce the CO2 concentration, purifying the air to maintain oxygen concentrations ranging between 18% and 21%. Also, in the green core, HouseTalk can effectively improve the cooling effect by up to 77% without HVAC.The reported thermal sensation indicates that over 90% of tenants are satisfied by HouseTalk's HVAC control. We demonstrate the potential of enhancing air quality through the photosynthesis by indoor plants. HouseTalk can effectively speed up the reduction of carbon dioxide concentrations by 53%. The oxygen concentration for the HouseTalk scenario ranges between 18% and 21%, which is always higher than that of the baseline scenario.

The ultra-high voltage (UHV) Lateral-diffused MOSFET (LDMOS) transistor has been widely used in power circuit applications and also used as an electrostatic discharge (ESD) self-protection device. However, the ESD ability of an UHV LDMOS is generally worse than that of low- and high-voltage (HV) devices, which means this UHV LDMOS device can be easily failed under an ESD event. Then, the method of embedded a silicon-controlled rectifier (SCR) into the HV LDMOS has been used in the HV circuit as an ESD protection technique. But when this architecture is applied to UHV devices, will its ESD capability be as good as in HV devices? A novel SCR with a P-body well architecture is proposed, which can effectively enhance the ESD ability of the UHV nLDMOS device when the drain side is embedded this new structure. The proposed structure can greatly improve the ESD capability of the device without adding any extra process step (& photomask), layout area and affecting the basic breakdown voltage. Finally, the proposed structure of the PPP-arranged type with the P-body well can greatly increase the ESD (FOM) ability which $\text{I}_{\mathrm{ t2}}$ and HBM ability can be increased by 68.7% and 22.2% (72.9%), respectively, as compared with the conventional SCR PPP-arranged type.

We determined the optical and electrical characteristics of GaN-based, ultraviolet micro light emitting diodes (microLEDs). Such microLEDs are essential to next-generation high-resolution micro-displays. Square-shaped microLEDs of different sizes (side lengths: 5-50 μm) were designed. The peak emission wavelength of these devices shifted

This study with the area-efficient design for improving electrostatic discharge (ESD) and Latch-up (LU) abilities in the ultra-high voltage (UHV) n-channel Lateral-Diffused MOSFET (nLDMOS) is investigated via a TSMC 0.5- $\mu \text{m}$ UHV Bipolar CMOS DMOS (BCD) process. There are two architectures of these nLDMOS devices with embedded Schottky diodes in the electrode area. Firstly, the drain side is divided into three concentric circles and embedded with Schottky diodes. The influence of these samples with different layout arrangements on ESD is evaluated. For the second item, UHV nLDMOS devices with the source side embedded Schottky diodes by two alternative layout types are developed. Experimental results showed that an UHV nLDMOS with embedded Schottky diodes at the drain side can significantly improve ESD ability, especially for the fully embedded Schottky diodes at the drain side (being with the highest figure of merit (FOM) value in the ESD, LU, and cell-area considerations). On the other hand, with embedded Schottky diodes at the source side can increase the holding voltage which can effectively improve the LU immunity.

Ecological adaptation is frequently inferred by the comparison of natural populations from different environments. Nevertheless, inference of the selective forces suffers the challenge that many environmental factors covary. With well-controlled environmental conditions, experimental evolution provides a powerful approach to complement the analysis of natural populations. On the other hand, it is apparent that laboratory conditions differ in many ways from natural environments, which raises the question as to what extent selection responses in experimental evolution studies can inform us about adaptation processes in the wild. In this study, we compared the expression profiles of replicated Drosophila melanogaster populations which have been exposed to two distinct temperature regimes (18/28 and 10/20°C) in the laboratory for more than 80 generations. Using gene-wise differential expression analysis and co-expression network analysis, we identified 541 genes and three coregulated gene modules that evolved in the same direction in both temperature regimes, and most of these changes probably reflect an adaptation to the space constraint or diurnal temperature fluctuation that is common in both selection regimes. In total, 203 genes and seven modules evolved temperature-specific expression changes. Remarkably, we detected a significant overlap of these temperature-adaptive genes/modules from experimental evolution with temperature-adaptive genes inferred from natural Drosophila populations covering two different temperature clines. We conclude that well-designed experimental evolution studies are a powerful tool to dissect evolutionary responses.

N-glycans on the cell surface provide distinct signatures that are recognized by different glycan-binding proteins (GBPs) and pathogens. Most glycans in humans are asymmetric and isomeric, yet their biological functions are not well understood due to their lack of availability for studies. In this work, we have developed an improved strategy for asymmetric N-glycan assembly and diversification using designed common core substrates prepared chemically for selective enzymatic fucosylation and sialylation. The resulting 26 well-defined glycans that carry the sialic acid residue on different antennae were used in a microarray as a representative application to profile the binding specificity of hemagglutinin (HA) from the avian influenza virus (H5N2). We found distinct binding affinity for the Neu5Ac-Gal epitope linked to the N-acetylglucosamine (GlcNAc) of different branches and only a minor effect in binding for the terminal galactose on different branches. Overall, the microarray analysis showed branch-biased and context-based recognition patterns.

G-quadruplex (G4) is a noncanonical secondary structure of DNA or RNA which can enhance or repress gene expression, yet the underlying molecular mechanism remains uncertain. Here we show that when positioned downstream of transcription start site, the orientation of potential G4 forming sequence (PQS), but not the sequence alters transcriptional output. Ensemble in vitro transcription assays indicate that PQS in the non-template increases mRNA production rate and yield. Using sequential single molecule detection stages, we demonstrate that while binding and initiation of T7 RNA polymerase is unchanged, the efficiency of elongation and the final mRNA output is higher when PQS is in the non-template. Strikingly, the enhanced elongation arises from the transcription-induced R-loop formation, which in turn generates G4 structure in the non-template. The G4 stabilized R-loop leads to increased transcription by a mechanism involving successive rounds of R-loop formation., G-quadruplex (G4) forming sequences are highly enriched in the human genome and function as important regulators of diverse range of biological processes. Here the authors show that while G4 structures on template strand block transcription, folding on the non-template strand enhances transcription by means of successive R-loop formation.

This study presents a backside loading design inductive tactile sensor with the monolithic integration of thermometer. Based on the commercially available standard complementary metal-oxide-semiconductor (CMOS) process (the TSMC $0.35\mu \text{m}$ 2P4M CMOS process) and the in-house post CMOS processes, the sensing chip is designed and implemented. The electrical connection is further achieved by using the flip-chip bonding process, and hence the breakage of bonding wires by the tactile load can be avoided. The CMOS sensing chip consists of the magnetic sensing coil and the polysilicon RTD (resistive thermal detector). Moreover, a cavity is defined on the backside (silicon substrate) of CMOS chip to act as a mold for the polymer filler as well as the housing for the chrome steel ball contact interface. The tactile force will cause the polymer deformation and chrome steel ball displacement, and further lead to the magnetic flux change on the sensing coil. Thus, the tactile force is detected by the inductance variation of magnetic sensing coil on the CMOS chip. Moreover, the temperature variation is detected by the resistance change of RTD thermometer, and the in-situ temperature monitoring during tactile loading is achieved. The force response of the proposed tactile sensor and the temperature response of the thermometer have been characterized. The influence of temperature variation on the tactile sensor has also been calibrated. Moreover, the characteristics of the thermometer on sensing chip at different contact conditions are also investigated.

Arsenic (As) contamination in paddy soil can cause phytotoxicity and elevated As accumulation in rice grains. Arsenic detoxification is closely linked to sulfur assimilation, but the genes involved have not been described in rice. In this study, we characterize the function of OASTL-A1, an O-acetylserine(thiol) lyase, in cysteine biosynthesis and detoxification of As in rice. Tissue expression analysis revealed that OsOASTL-A1 is mainly expressed in roots at the vegetative growth stage and in nodes at the reproductive stage. Furthermore, the expression of OsOASTL-A1 in roots was strongly induced by As exposure. Transgenic rice plants expressing pOsOASTL-A1::GUS (β-glucuronidase) indicated that OsOASTL-A1 was strongly expressed in the outer cortex and the vascular cylinder in the root mature zone. Subcellular localization using OsOASTL-A1:eGFP (enhanced green fluorescent protein) fusion protein showed that OsOASTL-A1 was localized to the cytosol. In vivo and in vitro enzyme activity assays showed that OsOASTL-A1 possessed the O-acetylserine(thiol) lyase activity. Knockout of OsOASTL-A1 led to significantly lower levels of cysteine, glutathione, and phytochelatins in roots and increased sensitivity to arsenate stress. Furthermore, the osoastl-a1 knockout mutants reduced As accumulation in the roots, but increased As accumulation in shoots. We conclude that OsOASTL-A1 is the cytosolic O-acetylserine(thiol) lyase that plays an important role in non-protein thiol biosynthesis in roots for As detoxification.

Recently, in IoT, wireless sensor network has become a critical technology with which many applications in industries and human life can achieve smart IoT control. However, for those daily applications using WSN technology, malicious users can capture the sensor nodes much easily since these wireless sensor nodes are usually deployed in easily touched places. Once this node captured attack occurs, wireless sensor network soon faces various security risks. In this paper, in order to resist node captured attack, we propose a novel authentication information exchange scheme in WSN, which is very different from the previous authentication researches. Our idea is to add an authentication information exchange scheme in previous authentication scheme but not propose new one. We develop this scheme based on the idea of the association scheme of Home GWN and local sensor nodes. In this study, HGWN should contact all local sensor nodes and meanwhile is responsible for performing an authentication information exchange scheme for resisting security risk. In order to prevent the attacker from guessing communication period between HGWN and the sensor, we also design a dynamic contacting mechanism. We give a detail discussion of this scheme and validate it by three ways, security evaluation, BAN logic and performance evaluation, which proves that our authentication information exchange scheme can achieve security features and goals.

Quantum communication via seawater channels has attracted much attention. Here, we present the design and implementation of a prototype for space-to-underwater quantum key distribution (QKD). The influence of the fluctuating atmosphere–seawater interface is theoretically analyzed. The setup consists of a specially designed optical source working in the blue–green band and a receiving optical antenna with large field-of-view (FOV). To achieve a larger FOV, photomultipliers with 25 mm active area are adopted to measure the single photon signals. The proof-of-principle experiment of QKD was implemented in the laboratory with near-coast seawater to verify the performance of the devices. This study provides a first step towards space-to-underwater quantum communication.

For high-volume manufacturing of 2-D transistors, area-selective chemical reaction deposition (CVD) growth is able to provide good-quality 2-D layers and may be more effective than exfoliation from bulk crystals or wet/dry transfer of large-area as-grown 2-D layers. We have successfully grown continuous and uniform WS2 film comprising around seven layers by area-selective CVD approach using patterned tungsten source/drain metals as the seeds. The growth mechanism is inferred and supported by the transmission electron microscope (TEM) images, as well. The first top-gate MOSFETs of CVD-WS2 channels on SiO x /Si substrates are demonstrated to have good short channel electrical characteristics: ON-/OFF-ratio of 106, a subthreshold swing of 97 mV/decade, and nearly zero drain-induced barrier lowering (DIBL).

A variable-delay optical interferometer with 128 actively selectable delays and a system of active phase stabilization with closed-loop feedback are innovatively designed and applied for the first time in the experiment of round-robin differential phase shift quantum key distribution (RRDPS-QKD). The active phase stabilization technique employs a phase modulator (PM) driven by a digital–analog converter (DAC) to adjust the relative phase between the two arms of the interferometer. By monitoring photon counting rates of two up-conversion detectors (UCDs) at two output ports of the interferometer, a field-programmable gate array (FPGA) calculates and finds the optimal code value for the DAC, maintaining high visibility of the interferometer every time a new light path is selected. A high proportion up to 100% of the visibility of interferometer selections can simultaneously be maintained over 96% during the QKD, which lays the foundation for the RRDPS experiment and yields possibilities for reprogrammable optical circuits.

The high-speed serial transceiver plays a key role in the high-speed data transmission. Because of the independent clock network in each transceiver, there exist random skews between the multiple transceivers each time the system reinitializes. In the system of data transmission, these random skews are always permitted and the intrachannel synchronization is guaranteed by inserting some same comma codes in each channel. However, for the strict clock distribution system, these random skews are unacceptable. To address this problem, a scheme combined of a tunable phase interpolator (PI) and a high-precision time-to-digital converter (TDC) is presented. A plain TDC is employed to measure the skews of parallel clocks in multichannels with bin size of ~10.2 ps and precision of ~18.0 ps. The method of multiple measurements average is adopted to further improve the TDCs performance. On this basis, time synchronization with root mean square (rms) of ~2.5 ps and peak-to-peak value of ~14.7 ps is implemented in a 20-nm fabrication process ultrascale field programmable gate array (FPGA). Compared to the measured results (rms of ~22 ps and peak-to-peak value of ~105 ps) of the Xilinx self-phase alignment method, the presented scheme has more than six times performance improvement. In addition, this scheme can lock the delay between different channels to arbitrary configurable offsets, making it very suitable for scenarios where multichannel latencies are strictly restricted.

Two ultra-low-noise balanced detectors used for optical time-domain measurements are presented in this paper. Both simultaneously achieve high bandwidth and low noise that is extremely difficult to realize in commercial detectors. Two-stage amplification circuits based on transimpedance amplifiers (TIAs) were used for these detectors, with special modifications implemented for different applications. To further suppress noise, a low-noise junction field-effect transistor is connected between the photodiode and TIA to reduce the impact of amplifier leakage current in one of the detectors. Benefiting from this design, a 70-MHz sensitive detector with a gain of 3.2E5 V/W and low noise-equivalent power (NEP) density of 2.2 pW/rtHz was implemented. For another balanced detector used in higher bandwidth applications, the differential TIA circuit is used, with the detector achieving a 250-MHz bandwidth with a gain of 5E4 V/W, equivalent to NEP of 6.2 pW/rtHz. Due to the difficulty of achieving high bandwidth with low noise, we perform theoretical analysis and simulations for our designs to ensure that these two design goals are realized simultaneously. The performance of the detectors is consistent with our analysis. In addition, a simplified optical testing system was built to test and calculate the performance of the detectors in their respective applications. The results show that both detectors are well-balanced and achieve a common mode rejection ratio greater than 50 dB.

This letter presents a simple approach to implement the inductive-type micro tri-axial tactile sensor by integrating a complementary metal–oxide–semiconductor (CMOS) chip with sensing coils and a stainless steel sheet (as the sensing interface) using polymer encapsulation. In addition to the component integration, the polymer layer is exploited as the spring for the tactile sensor. The proposed CMOS-MEMS inductive tri-axial tactile sensor presents several features and advantages as follows: 1) the gap-closing inductive sensing approach is used for normal force ( ${Z}$ -axis) detection; 2) the area-change inductive sensing method is adopted for shear forces’ ( ${X}$ -axis and ${Y}$ -axis) detection; 3) the compact sensing coil array is implemented using the standard CMOS process; and 4) the polymer is employed as the encapsulation layer to cover and integrate the rigid stainless steel sheet sensing interface and the CMOS chip, while also acting as the spring to avoid the fragile suspended thin-film structure. To demonstrate the concept, a CMOS sensing chip with a $2\times 2$ coil array is fabricated using the Taiwan Semiconductor Manufacturing Company standard process and is further integrated with a stainless steel sheet prepared by laser machining. The measurements indicate that the typical fabricated tri-axial inductive tactile sensor exhibits a normal load sensitivity ( ${Z}$ -axis) of 2.9 nH/N, an ${X}$ -axis shear force sensitivity of 17.4 nH/N, and a ${Y}$ -axis shear force sensitivity of 15.3 nH/N.

Major sugar constituents in young coconut husk were found to be glucans (0.30 g/g husk), while xylans were 0.10 g/g husk. Pre-treatments were carried out using phosphoric acid with dried coconut husk powder under steam heating. The effect of phosphoric acid on coconut husk hydrolysis was observed using acid concentrations of 0%, 1%, 5% and 10% (v/v). Soluble sugar concentration in hydrolysate was increasing proportional to acid concentration, as the total recovered solid decreases. FTIR and XRD analysis showed that acid hydrolysis led to the disruption of internal chemical bonds, causing coconut husk structural sugars to be released into the hydrolysate. Highest soluble sugar concentration, 29.9 g/L with a total suspended solid of 75.1 g/L, was obtained when the coconut husk was pre-treated with 10% phosphoric acid, and can be utilised for biohydrogen fermentation. Biotoxicity testing of the hydrolysates shows that half-maximal inhibition concentration of phosphoric acid was around 4.41% for a 24-h incubation and 3.80% for a 96-h incubation.

Apart from the reported energy transfer mechanism of aggregation-induced electrochemiluminescence (AI-ECL) enhancement, a new strategy named restriction of intramolecular motions-driven ECL (RIM-ECL) enhancement is first proposed based on the phenomenon of a very strong electrochemiluminescence observed on the hexagonal tetraphenylethylene microcrystals (TPE MCs) in aqueous solution. Compared to TPE in molecule-isolation state with faint ECL, TPE in aggregate state (TPE MCs) showed a significantly enhanced ECL that was due to the restriction of intramolecular motions (RIM). Inspired by the unique luminescence characteristic of TPE MCs, we integrated the novel ECL emitter of TPE MCs and target-activated bipedal DNA walker together to fabricate a sensitive "off-on" ECL biosensor for Mucin 1 (MUC1) assay, which exhibited desirable linear response for a concentration scope from 1 fg/mL to 1 ng/mL with a low detection limit of 0.29 fg/mL. The RIM enhanced ECL demonstrated by the TPE MCs provides a new chapter in the exploration of aggregated organic emitters for further applications.

DC-SIGN and langerin receptors both bind to oligomannose but lead to opposite effects upon encountering HIV. Because selective targeting of DC-SIGN can lead to anti-viral effects, we developed a glycoconjugate, which provides over 4800-fold selectivity for DC-SIGN over langerin, by controlling the oligomannose pattern on a polyproline tetra-helix macrocycle scaffold.

In this work, an electrochemiluminescent (ECL) biosensor was constructed on the basis of amino-modified 3,4,9,10-perylenetetracarboxylic dianhydride/luminol (PTC-NH2/Lu) nanocomposite as emitter and bipedal DNA walker signal amplification strategy for ultrasensitive detection of microRNA-21 (miRNA-21). The PTC-NH2/Lu nanocomposite was prepared as signal tag via π-π stacking molecular assembly, in which amino-modified 3,4,9,10-perylenetetracarboxylic dianhydride (PTC-NH2) as a novel coreaction accelerator significantly enhanced the ECL emission of luminol-H2O2 system. Moreover, target miRNA-21 triggered bipedal DNA walker was powered by toehold-mediated strand displacement reaction (TSDR) for signal amplification. Consequently, the proposed ECL biosensor achieved ultrasensitive detection of miRNA-21 with a linear range from 100 aM to 100 pM and a limit of detection of 33 aM. Simultaneously, the biosensor was also successfully applied to detect target miRNA-21 in lysates from human cancer cells. As a result, this work constructed a new signal amplification platform, exhibiting great application potential in biomedical analysis and early clinical diagnostics.

Double-gated monolayer two-dimensional (2D) material transistor is expected to offer ideal (~60 mV/dec) subthreshold swing (SS) for gate lengths well below 10 nm. However, the ideal 2D transistor assumes Ohmic contacts whereas a realistic metal/2D Schottky contact can degrade SS. Transport simulations including scattering is necessary to correctly describe carrier thermalization and predict the SS degradation. Scaled 2D transistors with a Schottky barrier height (SBH) smaller than 100 meV and doping concentration in the extension region larger than 2x1013 cm-2 are required to achieve high performance.

Measurement-device-independent quantum key distribution (MDI-QKD) removes all detector side channels and enables secure QKD with an untrusted relay. It is suitable for building a star-type quantum access network, where the complicated and expensive measurement devices are placed in the central untrusted relay and each user requires only a low-cost transmitter, such as an integrated photonic chip. Here, we experimentally demonstrate a 1.25 GHz silicon photonic chip-based MDI-QKD system using polarization encoding. The photonic chip transmitters integrate the necessary encoding components for a standard QKD source. We implement random modulations of polarization states and decoy intensities, and demonstrate a finite-key secret rate of 31 bps over 36 dB channel loss (or 180 km standard fiber). This key rate is higher than state-of-the-art MDI-QKD experiments. The results show that silicon photonic chip-based MDI-QKD, benefiting from miniaturization, low-cost manufacture and compatibility with CMOS microelectronics, is a promising solution for future quantum secure networks., Comment: 30 pages, 12 figures

In this experiment, we demonstrate high reliability of CsPbBr 3 Perovskite Quantum Dots (PeQDs) which illuminates 530 nm wavelength photons by exciting source on GaAs single-junction solar cell (Above 3000 h) and explore the Luminescent Down Shifting (LDS) effect of the GaAs solar cell with PeQDs with and without thermal process. The best one result shows that J sc from 23.85 mA/cm2 to 22.99 mA/cm2(3.60% enhancement) and the efficiency from 17.41% to 15.57% (10.56% enhancement). The un-baked sample shows higher stability on EQE enhancement factor, slightly decreasing from 130% to 128%. Furtherly, the prolonged lifetime test for PeQDs exhibits considerable possibility in the future.

Butterflies fly with an abdomen oscillating relative to the thorax; the abdominal oscillation causes body parts to undulate translationally relative to the center of mass of a butterfly, which could generate a significant effect on flight. Based on experimental measurements, we created a numerical model to investigate this effect in a free-flying butterfly (Idea leuconoe). We fixed the motions of wing-flapping and thorax-pitching, and parametrized the abdominal oscillation by varied oscillating phase. To concentrate the analysis on translational dynamics, we used a motion of a thorax-abdomen node, a joint that the thorax and the abdomen rotate about, to express the translational motion of body parts relative to the center of mass. The results show that the abdominal oscillation enhances lift and thrust via the translational motion of the thorax-abdomen node relative to the center of mass. With the abdominal oscillating phase recorded from real butterflies, the abdominal oscillation causes the thorax-abdomen node to move downward relative to the center of mass in downstroke and move upward relative to the center of mass in upstroke. This constructive movement amplifies the wing-flapping speed relative to the center of mass, which enhances the angle of attack and the strength of leading- and trailing-edge vortices on the wings. The wings thereby generate increased values of instantaneous lift and thrust by 50.32% and 32.57% compared to the case of no abdominal oscillation. Natural butterflies are stated to utilize a particular phase offset of abdominal oscillation to fly. With comparing varied oscillating phases, only the abdominal oscillating phase recorded from natural butterflies produces the best constructive effect on the translational motion of thorax-abdomen node, which maximizes the lift and thrust generated on the wings. It clarifies that butterflies use this specific range of abdominal oscillating phase to regulate the translational motion between the thorax-abdomen node and the center of mass to enhance flight. Our work reveals the translational mechanism of the abdominal oscillation, which is as important as the thorax-pitching effect. The findings in this work provide insight into the flight of butterflies and the design of micro aerial vehicles.

A sensitive linear optical sampling (LOS) system with femtosecond precision was implemented and experimentally optimized for free-space time-frequency transfer. The effect of optical factors and electronic factors on timing jitter and sensitivity of LOS was quantitatively studied separately based on femtosecond optical frequency combs. These factors include the intensity of received signal light, the repetition frequency difference between two combs, the number of bits of the analog-to-digital converter, and the gain of the balanced detector. According to the experimental results, the performance of the LOS system was optimized and the minimum timing jitter of LOS was 2.06 fs when the power of the received signal light was 1 μW. Moreover, the sensitivity reached 3.03 nW when using a balanced detector with 160 K gain.

Measurement-device-independent quantum key distribution (MDI-QKD), based on two-photon interference, is immune to all attacks against the detection system and allows a QKD network with untrusted relays. Since the MDI-QKD protocol was proposed, fibre-based implementations have been rapidly developed towards longer distance, higher key rates, and network verification. However, owing to the effect of atmospheric turbulence, MDI-QKD over free-space channel remains experimentally challenging. Here, by developing the robust adaptive optics system, high precision time synchronization and frequency locking between independent photon sources located far apart, we realised the first free-space MDI-QKD over a 19.2-km urban atmospheric channel, which well exceeds the effective atmospheric thickness. Our experiment takes the first step towards satellite-based MDI-QKD. Moreover, the technology developed here opens the way to quantum experiments in free space involving long-distance interference of independent single photons., Comment: 14 pages, 3 figures

This study presents a monolithic integration of pressure, humidity and temperature sensing units to achieve an environmental sensing hub (Fig. 1). The proposed environmental sensing hub is realized using the TSMC $0.18\mu \mathrm{m}$ 1P6M CMOS platform, and follow-up in-house post-CMOS processes. The presented environmental sensing hub has three merits: (1) single-side microfabrication processes: for monolithic integration of pressure, humidity, and temperature sensors, (2) vertical integration design: for the temperature sensor and the high sensitive pressure sensor with corrugated diaphragm, and (3) novel capacitive humidity sensor design: pillar sensing electrodes array and surrounded polyimide filler for response time enhancement. Measurements show performances of proposed environmental sensing hub are: sensitivity of pressure sensor with corrugated structure is 0.969fF/kPa (0.197fF/kPa for reference type w/o corrugated structure), humidity sensor with sensitivity of 2.897fF/%RH and response time of 12.1 seconds, and resistance temperature detector with sensitivity of 0.26%/°C.

This research reports a monolithically integrated Humidity/Thermometer/Pressure sensor to realize an environment sensing hub. The environment sensing hub is designed and implemented using the TSMC $0.18 \mu \mathrm{m}$ 1P6M CMOS platform and the follow-up double-side post-CMOS micromachining processes. Features of this study are: (1) Small footprint with less packaging effort: monolithic integration of H/T/P sensors on a single chip, (2) Fast response time of relative-humidity (RH) sensor: removal of backside silicon by double-side post-CMOS process to enhance vapor diffusion of capacitive RH sensor. (3) Double-side post-CMOS process: simultaneously fabricating backside cavities for H/P sensors. Measurement results indicate the performances of the environment sensing hub: humidity sensor with sensitivity of 4.06fF/%RH and response time of 3.1sec (15.7sec for the reference type of conventional design), and pressure sensor with sensitivity of 0.79fF/kPa, thermometer with response of 15.8mV/°C.

The fabrication of quantum key distribution (QKD) systems typically involves several parties, thus providing Eve with multiple opportunities to meddle with the devices. As a consequence, conventional hardware and/or software hacking attacks pose natural threats to the security of practical QKD. Fortunately, if the number of corrupted devices is limited, the security can be restored by using redundant apparatuses. Here, we report on the demonstration of a secure QKD setup with optical devices and classical post-processing units possibly controlled by an eavesdropper. We implement a 1.25 GHz chip-based measurement-device-independent QKD system secure against malicious devices on \emph{both} the measurement and the users' sides. The secret key rate reaches 137 bps over a 24 dB channel loss. Our setup, benefiting from high clock rate, miniaturized transmitters and a cost-effective structure, provides a promising solution for widespread applications requiring uncompromising communication security., Comment: 28 pages, 5 figures, 4 tables

High-precision time synchronization for remote clocks plays an important role in fundamental science and real-life applications. However, the current time synchronization techniques have been shown to be vulnerable to sophisticated adversaries. There is a compelling need for fundamentally new methods to distribute high-precision time information securely. Here we propose a satellite-based quantum-secure time transfer (QSTT) scheme based on two-way quantum key distribution (QKD) in free-space, and experimentally verify the key technologies of the scheme via the Micius quantum satellite. In QSTT, a quantum signal (e.g., single photon) is used as the carrier for both the time transfer and the secret-key generation, offering quantum-enhanced security for transferring time signal and time information. We perform a satellite-to-ground time synchronization using single-photon-level signals and achieve a quantum bit error rate of less than 1%, a time data rate of 9 kHz and a time-transfer precision of 30 ps. These results offer possibilities towards an enhanced infrastructure of time-transfer network, whose security stems from quantum physics., Comment: Nature Physics in press

This study demonstrates a novel vertically integrated double-bridge design for tri-axial piezo-resistive force sensor using commercial available CMOS process (Fig. 1). The normal and shear force sensing capabilities are achieved by measuring the signal changes of three independent Wheatstone bridges embedded in two bridges (fixed-fixed beams). The proposed sensor design has three merits: (1) two orthogonal bridges enable the directional sensing for shear forces, (2) piezo-resistors and electrical routings embedded in two bridges are designed to form three independent Wheatstone bridges for tri-axial force sensing, (3) the footprint reduction of the sensing chip is achieved by the vertical integration of two bridges. The measurements demonstrate the feasibility of tri-axial force sensing, and indicate that the sensitivities of the proposed tri-axial force sensor are, respectively, normal force (Z-axis) −0.18 mV/N, shear force (X-axis) −7.46 mV/N, and shear force (Y-axis) 7.26 mV/N.

Herein, an electrochemiluminescence (ECL) immunosensor was fabricated for sensitive assay of mucin 1 (MUC1) employing Ab2 labeled CuS porous nanospheres (CuS PNSs) complexes as the signal probe. The prepared novel noble metal-free co-reaction accelerator of CuS PNSs with nice catalytic property for H2O2 decomposition enhanced the ECL response of N-(Aminobutyl)-N-(ethylisoluminol) (ABEI)/H2O2. Meanwhile, CuS PNSs with large specific surface area served as good carrier for ABEI functionalized Ag nanoparticles immobilization. Hence, the ECL signal has significantly boosted by the ABEI/H2O2/CuS PNSs ternary ECL system. This MUC1 immunosensor showed a broad linear range of 10 fg/mL–10 ng/mL with a detection limit of 3.7 fg/mL, indicating the proposed strategy offered a good model for the detection of protein markers.

Successful siRNA therapy requires suitable delivery systems with targeting moieties such as small molecules, peptides, antibodies, or aptamers. Galactose (Gal) residues recognized by the asialoglycoprotein receptor (ASGPR) can serve as potent targeting moieties for hepatocellular carcinoma (HCC) cells. However, efficient targeting to HCC via galactose moieties rather than normal liver tissues in HCC patients remains a challenge. To achieve more efficient siRNA delivery in HCC, we synthesized various galactoside derivatives and investigated the siRNA delivery capability of nanoparticles modified with those galactoside derivatives. In this study, we assembled lipid/calcium/phosphate nanoparticles (LCP NPs) conjugated with eight types of galactoside derivatives and demonstrated that phenyl β-d-galactoside-decorated LCP NPs (L4-LCP NPs) exhibited a superior siRNA delivery into HCC cells compared to normal hepatocytes. VEGF siRNAs delivered by L4-LCP NPs downregulated VEGF expression in HCC in vitro and in vivo and led to a potent antiangiogenic effect in the tumor microenvironment of a murine orthotopic HCC model. The efficient delivery of VEGF siRNA by L4-LCP NPs that resulted in significant tumor regression indicates that phenyl galactoside could be a promising HCC-targeting ligand for therapeutic siRNA delivery to treat liver cancer.

Rice is a major dietary source of the toxic metalloid arsenic. Reducing arsenic accumulation in rice grain is important for food safety. We generated transgenic rice overexpressing two aquaporin genes, OsNIP1;1 and OsNIP3;3, under the control of a maize ubiquitin promoter or the rice OsLsi1 promoter, and tested the effect on arsenite uptake and translocation. OsNIP1;1 and OsNIP3;3 were highly permeable to arsenite in Xenopus oocyte assays. Both transporters were localized at the plasma membrane. Knockout of either gene had little effect on arsenite uptake or translocation. Overexpression of OsNIP1;1 or OsNIP3;3 in rice did not affect arsenite uptake but decreased root-to-shoot translocation of arsenite and shoot arsenic concentration markedly. The overexpressed OsNIP1;1 and OsNIP3;3 proteins were localized in all root cells without polarity. Expression of OsNIP1;1 driven by the OsLsi1 promoter produced similar effects. When grown in two arsenic-contaminated paddy soils, overexpressing lines contained significantly lower arsenic concentration in rice grain than the wild-type without compromising plant growth or the accumulation of essential nutrients. Overexpression of OsNIP1;1 or OsNIP3;3 provides a route for arsenite to leak out of the stele, thus restricting arsenite loading into the xylem. This strategy is effective in reducing arsenic accumulation in rice grain.

This paper reports on efforts to improve the photovoltaic performance of crystalline silicon solar cells by combining the plasmonic scattering of silver nanoparticles (Ag NPs) with the luminescent downshifting (LDS) effects of Eu-doped phosphors. The surface morphology was examined using a scanning electron microscope in conjunction with ImageJ software. Raman scattering and absorbance measurements were used to examine the surface plasmon resonance of Ag NPs of various dimensions in various dielectric environments. The fluorescence emission of the Eu-doped phosphors was characterized via photoluminescence measurements at room temperature. We examined the combination of plasmonic and LDS effects by measuring the optical reflectance and external quantum efficiency. Improvements in the photovoltaic performance of the solar cells were determined by photovoltaic current density-voltage under AM 1.5G illumination. A combination of plasmonic and LDS effects led to an impressive 26.17% improvement in efficiency, whereas plasmonic effects resulted in a 22.63% improvement compared to the cell with a SiO2 ARC of 17.33%.

In this work, a sensitive electrochemiluminescent assay of mucin 1 (MUC1) was developed with the advantages of target recycling amplification strategy and effective MoS2 nanoflower (MoS2 NF)-based signal probe. Briefly, the target MUC1 triggered enzyme-free recycling and a double-output amplification process was executed to acquire masses of single-stranded DNA as a mimic target, which further participated in the catalytic hairpin assembly process for signal amplification. Meanwhile, MoS2 NFs were prepared as an effective co-reaction accelerator, which not only possessed excellent catalytic performance for H2O2 decomposition to largely enhance the luminous intensity of N-(aminobutyl)-N-(ethylisoluminol) (ABEI)-H2O2 electrochemiluminescence system but also offered a desirable platform for ABEI-functionalized Ag nanoparticles (ABEI–Ag complexes) loading via Ag–S binding. The experimental results showed the proposed aptasensor had a good linear relationship in the range of 1 fg/mL to 10 ng/mL for MUC1 detect...

Two practical and simple synthetic methodologies towards various heterobenzyl halides were developed. A series of 2-halomethylquinolines were readily prepared by the one-pot reaction of 2-methylquinolines with CuX (X = I, Br, Cl) and TBHP in CH3CN. A large variety of heterobenzyl iodides, including 2-iodomethylquinolines, 2-iodomethylquinoxalines, 2-iodiomethylbenzooxazole, and 2-iodiomethylbenzothiazole, were efficiently synthesized by one-pot reaction of 2-methylheterocycles with iodine in the presence of CuSO4·5H2O in CH3CN.

Stress variation induced bandgap tuning and surface wettability switching of spinel nickel ferrite (NiFe2O4, NFO) films were demonstrated and directly driven by phase transition via a post-annealing process. Firstly, the as-deposited NFO films showed hydrophilic surface with water contact angle (CA) value of 80 ± 1°. After post-annealing with designed temperatures ranged from 400 to 700 °C in air ambience for 1 hour, we observed that the crystal structure was clearly improved from amorphous-like/ nanocrystalline to polycrystalline with increasing post-annealing temperature and this phenomenon is attributed to the improved crystallinity combined with relaxation of internal stress. Moreover, super-hydrophilic surface (CA = 14 ± 1°) was occurred due to the remarkable grain structure transition. The surface wettability could be adjusted from hydrophilicity to super-hydrophilicity by controlling grain morphology of NFO films. Simultaneously, the saturation magnetization (Ms) values of NFO films at room temperature increased up to 273 emu/cm3 accompanied with transitions of the phase and grain structure. We also observed an exceptionally tunable bandgap of NFO in the range between 1.78 and 2.72 eV under phase transition driving. Meanwhile, our work demonstrates that direct grain morphology combined with the stress tuning can strongly modulate the optical, surface and magnetic characteristics in multifunctional NFO films.

In this work, a simple and effective method with different thicknesses in the ranges of 100–300 nm of insulating layer was investigated to enhance the performance of resistive switching behavior in polymetallic oxide-based spinel nickel ferrite (NiFe2O4) resistive switching memristor. The Pt/NiFe2O4/Pt capacitor-like device with an optimum 200 nm thick insulating layer has been found to operate at room temperature in unipolar resistive switching (URS) mode and with narrow distribution and less fluctuation on endurance property, and then switches the highly distinguishable (ON/OFF ratio >100 times), reversible and reproducible between the ON and OFF states. The Pt/NiFe2O4/Pt symmetric layered structure using a designed 200 nm insulating layer without any further post-deposition annealing demonstrates higher stability without any inter-overlap signal between high resistive state (HRS) and low resistive state (LRS) transition. The optimum characteristic in NiFe2O4 operating control is without any abnormal resistive switching behavior. Such a designed insulating layer with critical thickness plays a key role to enhance the comprehensive performance of the switching behavior, which could be a simple and effective method with a high successful rate of fabrication for requirements of industrial technology. This work could provide a solid foundation in multi-functional devices and make a stepping forward to the universal memristor with an extremely low-temperature process in the future.

Solventogenic clostridia has been considered as one of the most potential microbial cell factories for biofuel production in the biorefinery industry. However, the inherent shortcomings of clostridia strains such as low productivity, by-products formation and toxic tolerance still strongly restrict the large-scale application. Therefore, concerns regarding the genetic modification of solventogenic clostridia have spurred interests into the development of modern gene-editing tools. In this review, we summarize the latest advances of genetic tools involved in modifying solventogenic clostridia. Following a systematic comparison on their respective characteristics, we then review the corresponding strategies for overcoming the obstacles to the enhanced production. Discussing the progress of other microbial cell factories for solventogenesis, we finally describe the key challenges and trends with valuable recommendations for future large-scale biosolvent industrial application.

Purpose Based on laser-range-finder (LRF) sensing, the control design of location and orientation stabilization for the mobile robot is investigated. However, the practical limitation of the LRF sensing is usually ignored in the control design, which leads to incorrect localization and unexpected control results. The purpose of this study is to design the fuzzy controller subject to the practical limitation on the LRF-based localization for a differentially driven wheeled mobile robot. Design/methodology/approach First, the Takagi–Sugeno (T-S) fuzzy model is derived from the polar kinematic model of a differentially driven mobile robot. Then, the fuzzy controller is designed to the derived T-S fuzzy kinematic model in accordance with the Lyapunov stabilization theorem. The derived Lyapunov stabilization conditions for the fuzzy control design are expressed as the linear matrix inequality (LMI) form and effectively solved by LMI tools. The practical limitation on the LRF-based localization is also expressed as the LMI form and simultaneously solved with the control design. Finding The location and posture stabilization experiments are carried out on a mobile robot with LRF-based localization to prove the effectiveness of the proposed T-S fuzzy model-based control design. Furthermore, the ground truth experiment evaluates the accuracy of LRF-based localization. Originality/value The contribution of this study is to develop the fuzzy control law for a differentially driven wheeled mobile robot under the practical limitation on LRF-based localization. The proposed control design can be applied to other robots with practical limitations on the sensors.

An arbitrary unknown quantum state cannot be precisely measured or perfectly replicated. However, quantum teleportation allows faithful transfer of unknown quantum states from one object to another over long distance, without physical travelling of the object itself. Long-distance teleportation has been recognized as a fundamental element in protocols such as large-scale quantum networks and distributed quantum computation. However, the previous teleportation experiments between distant locations were limited to a distance on the order of 100 kilometers, due to photon loss in optical fibres or terrestrial free-space channels. An outstanding open challenge for a global-scale "quantum internet" is to significantly extend the range for teleportation. A promising solution to this problem is exploiting satellite platform and space-based link, which can conveniently connect two remote points on the Earth with greatly reduced channel loss because most of the photons' propagation path is in empty space. Here, we report the first quantum teleportation of independent single-photon qubits from a ground observatory to a low Earth orbit satellite - through an up-link channel - with a distance up to 1400 km. To optimize the link efficiency and overcome the atmospheric turbulence in the up-link, a series of techniques are developed, including a compact ultra-bright source of multi-photon entanglement, narrow beam divergence, high-bandwidth and high-accuracy acquiring, pointing, and tracking (APT). We demonstrate successful quantum teleportation for six input states in mutually unbiased bases with an average fidelity of 0.80+/-0.01, well above the classical limit. This work establishes the first ground-to-satellite up-link for faithful and ultra-long-distance quantum teleportation, an essential step toward global-scale quantum internet., 16 pages, 3 figures

The first Ni-catalyzed ortho-sulfonylation of C(sp2)–H bonds with sodium sulfinates directed by (pyridin-2-yl)isopropylamine (PIP-amine) is described. This strategy exhibits a broad substrate scope and good functional group tolerance with high monosulfonylation selectivity. Besides arenes and heteroarenes, the reaction can also be extended to alkenes, providing diverse diaryl and alkyl-aryl sulfones in high yields. Furthermore, a plausible Ni(I)/Ni(III) mechanism is outlined based on our experimental results and related precedents.

The sequential deposition process is widely used to fabricate planar structure perovskite solar cells because of better uniformity and perfect surface coverage of perovskite films. However, it is difficult to control the crystallization of perovskite finely. Here, we improve the sequential deposition process by using a low-pressure proximity evaporation technique. The slow grain growth rate of perovskite (CH3NH3PbI3 ) would make large crystallization and high quality of perovskite film. Moreover, we manipulate an innovative double-side interdiffusion process, that is, sequentially deposit CH3NH3I/PbI2/CH 3NH3I to fabricate the perovskite layer. This way, PbI2 can be effectively converted into perovskite from a double side and achieve good control of CH3NH3I deposition on the surface as well. The devices reach an efficiency over 14%, which is the first time for TiO2 free cells fabricated by a low-pressure approach.

Polarization modulation plays a key role in polarization-encoding quantum key distribution (QKD). Here, we report a new, to the best of our knowledge, polarization modulation scheme based on an inherently stable Sagnac interferometer. The presented scheme is free of polarization mode dispersion and calibration as well as insensitive to environmental influences. Successful experiments at a repetition frequency of 1.25 GHz have been conducted to demonstrate the feasibility and stability of the scheme. The measured average quantum bit-error rate of the four polarization states is as low as 0.27% for 80 consecutive minutes without any adjustment. This high-speed intrinsically stable polarization modulation can be widely applied to many polarization-encoding QKD systems, such as BB84, MDI, etc.

Single-photon detectors (SPDs) play important roles in highly sensitive detection applications, such as fluorescence spectroscopy, remote sensing and ranging, deep space optical communications, elementary particle detection, and quantum communications. However, the adverse conditions in space, such as the increased radiation flux and thermal vacuum, severely limit their noise performances, reliability, and lifetime. Herein, we present the example of spaceborne, low-noise, high reliability SPDs, based on commercial off-the-shelf (COTS) silicon avalanche photodiodes (APD). Based on the high noise-radiation sensitivity of silicon APD, we have developed special shielding structures, multistage cooling technologies, and configurable driver electronics that significantly improved the COTS APD reliability and mitigated the SPD noise-radiation sensitivity. This led to a reduction of the expected in-orbit radiation-induced dark count rate (DCR) increment rate from ∼219 counts per second (cps) per day to ∼0.76 cps/day. During a continuous period of continuous operations in orbit which spanned of 1029 days, the SPD DCR was maintained below 1000 cps, i.e., the actual in-orbit radiation-induced DCR increment rate was ∼0.54 cps/day, i.e., two orders of magnitude lower than those evoked by previous technologies, while its photon detection efficiency was > 45%. Our spaceborne, low-noise SPDs established a feasible satellite-based up-link quantum communication that was validated on the quantum experiment science satellite platform. Moreover, our SPDs open new windows of opportunities for space research and applications in deep-space optical communications, single-photon laser ranging, as well as for testing the fundamental principles of physics in space.

A heterojunction-Schottky diode has a low forward-voltage drop and a fast switching feature. Therefore, in this paper, the drain side heavily doped region was removed and equivalently added a heterojunction device in 60 V n/pLDMOS devices, and evaluating its ability of ESD immunity. From the TLP measure result, the optimized secondary breakdown current of nLDMOS can be increased from 2.35 A to 3.85 A (improved 63.8%); the optimized secondary breakdown current of pLDMOS can be increased from 0.78 A to 2.83 A (improved 263%). It can be found that from removing the drain-side heavily doped region in LDMOS, LDMOS devices are equivalent with a large series heterojunction device, they are indeed very effective in improving the ESD reliability of n/pLDMOS devices.