Highly stable power control for chip-based continuous-variable quantum key distribution system.

Quantum key distribution allows secret key generation with information theoretical security. It can be realized with photonic integrated circuits to benefit the tiny footprints and the large-scale manufacturing capacity. Continuous-variable quantum key distribution is suitable for chip-based integration due to its compatibility with mature optical communication devices. However, the quantum signal power control compatible with the mature photonic integration process faces difficulties on stability, which limits the system performance and causes the overestimation of a secret key rate that opens practical security loopholes. Here, a highly stable chip-based quantum signal power control scheme based on a biased Mach-Zehnder interferometer structure is proposed, theoretically analyzed, and experimentally implemented with standard silicon photonic techniques. Simulations and experimental results show that the proposed scheme significantly improves the system stability, where the standard deviation of the secret key rate is suppressed by an order of magnitude compared with the system using traditional designs, showing a promising and practicable way to realize a highly stable continuous-variable quantum key distribution system on chip.

Study on synergistic mechanism of molybdenum disulfide/sodium carboxymethyl cellulose composite nanofiber mats for photothermal/photodynamic antibacterial treatment.

Innovative antibacterial therapies using nanomaterials, such as photothermal (PTT) and photodynamic (PDT) treatments, have been developed for treating wound infections. However, creating secure wound dressings with these therapies faces challenges. The primary focus of this study is to prepare an antibacterial nanofiber dressing that effectively incorporates stable loads of functional nanoparticles and demonstrates an efficient synergistic effect between PTT and PDT. Herein, a composite nanofiber mat was fabricated, integrating spherical molybdenum disulfide (MoS2) nanoparticles. MoS2 was deposited onto polylactic acid (PLA) nanofiber mats using vacuum filtration, which was further stabilized by sodium carboxymethyl cellulose (CMC) adhesion and glutaraldehyde (GA) cross-linking. The composite nanofibers demonstrated synergistic antibacterial effects under NIR light irradiation, and the underlying mechanism was explored. They induce bacterial membrane permeability, protein leakage, and intracellular reactive oxygen species (ROS) elevation, ultimately leading to >95 % antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), which is higher than that of single thermotherapy (almost no antibacterial activity) or ROS therapy (about 80 %). In addition, the composite nanofiber mats exhibited promotion effects on infected wound healing in vivo. This study demonstrates the great prospects of composite nanofiber dressings in clinical treatment of bacterial-infected wounds.

Food Security and Land Use under Sustainable Development Goals: Insights from Food Supply to Demand Side and Limited Arable Land in China.

The conflict between economic growth and the arable land demand poses a significant challenge to maintaining food security and achieving the Sustainable Development Goals. Meanwhile, substantial regional disparities in food consumption contribute to variations in land demand, further exacerbating constraints on food security. However, few studies have delved into regional differences in land demand related to food consumption. To bridge these gaps, this study estimated the arable land demand and associated pressures, considering food consumption patterns and the land footprint across 31 provincial districts in China. The findings reveal that grains remain the primary crop consumed by Chinese residents. Notably, the food consumption pattern exhibits substantial disparities among provincial districts, particularly concerning livestock products. Given China's vast population and escalating consumption of livestock, the country demonstrates heightened land demands. While China does not face a national-level food security threat, regional disparities are evident, with eight provincial districts facing potential food security risks. This study explored the challenges and pathways in maintaining food security and the visions to achieve it, emphasizing the importance of sustaining a balanced food consumption pattern, reducing food waste, improving environmentally friendly agriculture practices, formulating effective and continuous laws and regulations, and exploring potential land resource development to alleviate the pressure on arable land and ensure food security.

Nanofibrous Dressing with Nanocomposite Monoporous Microspheres for Chemodynamic Antibacterial Therapy and Wound Healing.

The excessive use of antibiotics and consequent bacterial resistance have emerged as crucial public safety challenges for humanity. As a promising antibacterial treatment, using reactive oxygen species (ROS) can effectively address this problem and has the advantages of being highly efficient and having low toxicity. Herein, electrospinning and electrospraying were employed to fabricate magnesium oxide (MgO)-based nanoparticle composited polycaprolactone (PCL) nanofibrous dressings for the chemodynamic treatment of bacteria-infected wounds. By utilizing electrospraying, erythrocyte-like monoporous PCL microspheres incorporating silver (Ag)- and copper (Cu)-doped MgO nanoparticles were generated, and the unique microsphere-filament structure enabled efficient anchoring on nanofibers. The composite dressings produced high levels of ROS, as confirmed by the 2,7-dichloriflurescin fluorescent probe. The sustained generation of ROS resulted in efficient glutathione oxidation and a remarkable bacterial killing rate of approximately 99% against Staphylococcus aureus (S. aureus). These dressings were found to be effective at treating externally infected wounds. The unique properties of these composite nanofibrous dressings suggest great potential for their use in the medical treatment of bacteria-infected injuries.

Beneficial effects of triadimefon in overcoming drought stress in soybean at fluorescence stage.

Soybean (Glycine max [L.] Merr.) at fluorescence stage frequently experiences drought stress. Although triadimefon has been observed to improve drought tolerance of plants, reports on its role in drought resistance on leaf photosynthesis and assimilate transport are limited. This study examined the effects of triadimefon on leaf photosynthesis and assimilate transport at fluorescence stage of soybean experiencing drought stress. Results showed that triadimefon application relieved the inhibitory effects of drought stress on photosynthesis and increased RuBPCase activity. Drought increased soluble sugar contents, yet reduced starch content in the leaves by heightening the activities of sucrose phosphate synthase (SPS), fructose-1,6-bisphosphatase (FBP), invertase (INV), and amylolytic enzyme, impeding the translocation of carbon assimilates to roots and reducing plant biomass. Nevertheless, triadimefon elevated starch content and minimized sucrose degradation by augmenting sucrose synthase (SS) activity and restraining the activities of SPS, FBP, INV, and amylolytic enzyme compared with drought alone, regulating the carbohydrate balance of drought-stressed plants. Therefore, triadimefon application could reduce the photosynthesis inhibition and regulate the carbohydrate balance of drought-stressed soybean plants to lessen the impacts of drought on soybean biomass.

Sub-Mbps key-rate continuous-variable quantum key distribution with local local oscillator over 100-km fiber.

We experimentally demonstrated a sub-Mbps key rate Gaussian-modulated coherent-state (GMCS) continuous-variable quantum key distribution (CV-QKD) over a 100-km transmission distance. To efficiently control the excess noise, the quantum signal and the pilot tone are co-transmitted in the fiber channel based on wideband frequency and polarization multiplexing methods. Furthermore, a high-accuracy data-assisted time domain equalization algorithm is carefully designed to compensate the phase noise and polarization variation in low signal-to-noise ratio. The asymptotic secure key rate (SKR) of the demonstrated CV-QKD is experimentally calculated to be 7.55 Mbps, 1.87 Mbps, and 0.51 Mbps over a transmission distance of 50 km, 75 km, and 100 km, respectively. The experimentally demonstrated that the CV-QKD system significantly improves the transmission distance and SKR compared to the state-of-art GMCS CV-QKD experimental results, and shows the potential for long-distance and high-speed secure quantum key distribution.

Enhancement of 15% calcium oxide doped nano zero-valent iron on arsenic removal from high-arsenic acid wastewater.

Nano zero-valent iron (nZVI) has a great potential for arsenic removal, but it would form aggregates easily and consume largely by H+ in the strongly acidic solution. In this work, 15%CaO doped with nZVI (15%CaO-nZVI) was successfully synthesized from a simplified ball milling mixture combined with a hydrogen reduction method, which had a high adsorption capacity for As(V) removal from high-arsenic acid wastewater. More than 97% As(V) was removed by 15%CaO-nZVI under the optimum reaction conditions of pH 1.34, initial As(V) concentration 16.21 g/L, and molar ratio of Fe/As (nFe/nAs) 2.5:1. The effluent pH solution was weakly acidic 6.72, and the secondary arsenic removal treatment reduced the solid waste and improved arsenic grade in slag from the mass fraction of 20.02% to 29.07%. Multiple mechanisms including Ca2+ enhanced effect, adsorption, reduction, and co-precipitation coexisted for As(V) removal from high-arsenic acid wastewater. Doping of CaO might lead to improving cracking channels which was benefit for electronic transmission and the confusion of atomic distribution. The in situ weak alkaline environment generated on the surface of 15%CaO-nZVI would increase the content of γ-Fe2O3/Fe3O4, which was in favor for As(V) adsorption. In addition, H+ in the strongly acidic solution could accelerate corrosion of 15%CaO-nZVI and abundant fresh and reactive iron oxides continuously generated, which would provide plenty specific reactive site and fast charge transfer and ionic mobility for arsenic removal.

NiOx for interface and work function engineering in carbon-based all-inorganic perovskite solar cells.

Carbon-based all-inorganic perovskite solar cells (C-IPSCs) are stable, upscalable and have low CO2-footprint to fabricate. However, they are inefficient in converting light to electricity due to poor hole extraction at perovskite/carbon interface. Here we enable an efficient hole extraction in C-IPSCs with the aid of inorganic p-type nickel oxide nanoparticles (NiOx-NPs) at the interface and in carbon. By tailoring the work function (WF) of carbon, and reducing the energy-level misalignment at the perovskite/carbon interface, NiOx-NPs enable efficient hole transfer, reduce charge recombination and minimize energy loss. As a result, we report 15.01% and 11.02% efficiencies for CsPbI2Br and CsPbIBr2 C-IPSCs, respectively, with a high open-circuit voltage of ∼1.3 V. Unencapsulated interface-modified CsPbI2Br devices maintained 92.8% of their initial efficiency at ambient conditions after nearly 2,000 h; and 94.6% after heating at 60 °C for 170 h. This strategy to tailor carbon interface with perovskite offers an important knob in improving C-IPSCs performance.

Performance analysis for OFDM-based multi-carrier continuous-variable quantum key distribution with an arbitrary modulation protocol.

Multi-carrier continuous-variable quantum key distribution (CV-QKD) is considered to be a promising way to boost the secret key rate (SKR) over the existing single-carrier CV-QKD scheme. However, the extra excess noise induced in the imperfect multi-carrier quantum state preparation process of N subcarriers will limit the performance of the system. Here, a systematic modulation noise model is proposed for the multi-carrier CV-QKD based on the orthogonal frequency division multiplexing (OFDM). Subsequently, the performance of multi-carrier CV-QKD with arbitrary modulation protocol (e.g. QPSK, 256QAM and Gaussian modulation protocol) can be quantitatively evaluated by combining the security analysis method of the single-carrier CV-QKD. Under practical system parameters, the simulation results show that the SKR of the multi-carrier CV-QKD can still be significantly improved by increasing the carrier number N even with imperfect practical modulations. Specifically, the total SKR of multi-carrier CV-QKD can be optimized by carefully choosing N. The proposed model provides a feasible theoretical framework for the future multi-carrier CV-QKD experimental implementation.

Theaflavin-3,3'-digallate ameliorates learning and memory impairments in mice with premature brain aging induced by D-galactose.

Age-related neurodegenerative diseases accompanied by learning and memory deficits are growing in prevalence due to population aging. Cellular oxidative stress is a common pathomechanism in multiple age-related disorders, and various antioxidants have demonstrated therapeutic efficacy in patients or animal models. Many plants and plant extracts possess potent antioxidant activity, but the compounds responsible are frequently unknown. Identification and evaluation of these phytochemicals is necessary for optimal targeted therapy. A recent study identified theaflavin-3,3'-digallate (TFDG) as the most potent among a large series of phytochemical antioxidants. Here we examined if TFDG can mitigate learning and memory impairments in the D-galactose model of age-related neurodegeneration. Experimental mice were injected subcutaneously with D-galactose (120 mg/kg) for 56 days. In treatment groups, different doses of TFDG were administered daily by gavage starting on day 29 of D-galactose injection. Model mice exhibited poor learning and memory in the novel object recognition and Y-maze tests, reduced brain/body mass ratio, increased brain glutamate concentration and acetylcholinesterase activity, decreased brain acetylcholine concentration, and lower choline acetyltransferase, glutaminase, and glutamine synthetase activities. Activities of antioxidant enzymes glutathione peroxidase and superoxide dismutase were also reduced, while the concentration of malondialdehyde, a lipid peroxidation product, was elevated. Further, antioxidant genes Nrf2, Prx2, Gsh-px1, and Sod1 were downregulated in brain. Each one of these changes was dose-dependently reversed by TFDG. TFDG is an effective antioxidant response inducer and neuroprotectant that can restore normal neurotransmitter metabolism and ameliorate learning and memory dysfunction in the D-galactose model of age-related cognitive decline.

Combined effect of elevated temperature and drought stress on carbohydrate metabolism of cotton (Gossypium hirsutum L.) subtending leaves.

High temperatures and drought are expected to become more frequent in the future and last longer than ever before. To investigate their combined effect on leaves subtending cotton boll (LSCB), an experiment was conducted from 2016 to 2018 using a nonheat-tolerant cotton cultivar and a heat-tolerant cultivar. Two temperature regimes with ambient temperature (AT, 31.0/26.4°C) and elevated temperature (ET, 33.4/28.9°C, 2.5°C higher than AT) and three drought treatments with a soil relative water content (SRWC) of 75 ± 5%, 60 ± 5%, and 45 ± 5% were established repeatedly. ET decreased net photosynthetic rate (Pn), initial rubisco activity (4.1.1.39, RuBP) and cytosolicfructose-1,6-bisphosphatase (cy-FBPase; 3.1.3.11) activity, upregulated GhSuSyA, and GhSuSyD expressions, and increased SuSy (2.4.1.13) activity, which led to the decline of the final starch and sucrose contents. Moreover, RuBP, Pn, and starch content all decreased with drop in SRWC levels, but the cy-FBPase and SPS (2.4.1.14) activity increased, which in turn increased sucrose content. Under combined stresses, when the changing trends of ET and drought effects were the same, the decrease of Pn, RuBP, and starch content was greater than under single stress exposure. However, when the changing trends of ET and drought effects were adverse, the combined effects on indicators such as cy-FBPase, SuSy, sucrose content were mostly similar to drought stress. These results indicate that the effect of drought on carbohydrate metabolism in LSCB is more prominent than ET. Thus, the drought effect for carbohydrate metabolism in LSCB may need more attention than ET under combined heat and drought stress.

Chemical and nutritional composition of Pamir yak milk from Xinjiang.

Pamir yak milk is considered to be ideal food for local people, but its nutritional profile has not yet been reported. This study investigated the chemical and nutritional composition of Pamir yak milk, and compared the results with reference composition of goat and cow milk. We found that the Pamir yak milk had higher contents of protein (4.30%), fat (4.63), lactose (5.21%) and total solid (14.84%) than that of goat and cow milk. The predominant amino acids were glutamate (20%), proline (10%), lysine (10%) and leucine (10%), of which the essential amino acids accounted for 48% of the total amino acids. Meanwhile, Pamir yak milk was rich in minerals such as Ca, Fe, Zn and Mg and thiamine (B1 ), niacin (B3 ), Pyridoxine (B6 ) and cobalamin (B12 ) were higher than those of cow and goat milk. Also, medium-chain fatty acids (C12-C16) exhibited the highest level. However, The α -linolenic acid (C18:3), eicosapentaenoic acid and docosahexaenoic acid were found in yak milk. All of the above-mentioned differences were demonstrated by the fact that the yak milk quality may be affecting by pasture production, animal species and nutritive value of the herbage. Therefore, Pamir yak milk is a promising alternative food that may contribute to human health.

Modeling of a multi-parameter chaotic optoelectronic oscillator based on the Fourier neural operator.

A model construction scheme of chaotic optoelectronic oscillator (OEO) based on the Fourier neural operator (FNO) is proposed. Different from the conventional methods, we learn the nonlinear dynamics of OEO (actual components) in a data-driven way, expecting to obtain a multi-parameter OEO model for generating chaotic carrier with high-efficiency and low-cost. FNO is a deep learning architecture which utilizes neural network as a parameter structure to learn the trajectory of the family of equations from training data. With the assistance of FNO, the nonlinear dynamics of OEO characterized by differential delay equation can be modeled easily. In this work, the maximal Lyapunov exponent is applied to judge whether these time series have chaotic behavior, and the Pearson correlation coefficient (PCC) is introduced to evaluate the modeling performance. Compare with long and short-term memory (LSTM), FNO is not only superior to LSTM in modeling accuracy, but also requires less training data. Subsequently, we analyze the modeling performance of FNO under different feedback gains and time delays. Both numerical and experimental results show that the PCC can be greater than 0.99 in the case of low feedback gain. Next, we further analyze the influence of different system oscillation frequencies, and the generalization ability of FNO is also analyzed.

Anchoring silver nanoparticles on nanofibers by thermal bonding to construct functional surface.

Generally, the anchoring of inorganic nanoparticles onto the surface of fibers faces the problem of poor stability, which limits the wide application of nanoparticle functionalized fibers. Herein, nanofibers with shell-core structures were constructed by coaxial electrospinning of two polymers with different melting points (Tm). Polyglycolic acid (PGA, Tm = 225 °C) was employed as the core layer, while polycaprolactone (PCL, Tm = 60 °C) was used as the shell layer. Silver nanoparticles (AgNPs) were electrosprayed on the nanofibers and the shell layer (PCL) was heated and melted to bond the AgNPs, thus realizing a stable AgNP-composited nanofiber for the construction of antibacterial functional surface. By regulating the shell-core flow ratio and the condition for heat treatment, the appropriate thickness of the shell layer was obtained with a flow ratio of 3:1 (PCL:PGA). The optimal composite structure was constructed when the thermal bonding was taken under 80 °C for 5 min. Furthermore, it was found that the composite nanofibers prepared by thermal bonding had better hydrophilicity, mechanical property, and AgNPs bonding stability, and their antibacterial rate against Staphylococcus aureus (S. aureus) reached over 97%. Overall, a facile and universal method for the preparation of nanoparticle-anchored nanofibers was established in this study. The robust nanoparticle-composited nanofibers are promising for applications in optoelectronic devices, electrode materials, and so on.

Exposure to melamine cyanuric acid in adult mice caused motor activity and skeletal muscle energy metabolism disorder.

Thyroid hormone has a variety of physiological functions and plays an important role in the development of central nervous system, skeletal muscle and lung, as well as body temperature regulation. Skeletal muscle is a key determinant of basal metabolic rate and systemic energy metabolism. It contains Myopsin (SLN) which plays an important role in muscle heat production and energy metabolism. Melamine cyanuric acid (MCA) is an important component of the new flame retardant, but also a chemical interfering substance that can affect the endocrine in the body. It is mainly distributed in nylon and other flame retardant substances. Therefore, in this study, male mice were exposed to MCA at 10, 20 and 30 mg/kg for four weeks. We explored the effects of MCA exposure on skeletal muscle morphology, thermogenic gene expression and motor activity to explore whether MCA exposure could induce skeletal muscle hyperthermia and energy metabolism disorders and its underlying mechanisms. The results showed that the motor activity of male mice exposed to MCA was decreased, the morphology of skeletal muscle tissue was impaired, and the levels of morphological and thermogenic genes in skeletal muscle were destroyed. These findings are intended to provide a preliminary reference for studying the effects of MCA exposure on thermogenesis and energy metabolism in adult mice.

Polarization Attack on Continuous-Variable Quantum Key Distribution with a Local Local Oscillator.

The estimation of phase noise of continuous-variable quantum key distribution protocol with a local local oscillator (LLO CVQKD), as a major process in quantifying the secret key rate, is closely relevant to the intensity of the phase reference. However, the transmission of the phase reference through the insecure quantum channel is prone to be exploited by the eavesdropper (Eve) to mount attacks. Here, we introduce a polarization attack scheme against the phase reference. Presently, in a practical LLO CVQKD system, only part of the phase reference pulses are measured to compensate for the polarization drift of the quantum signal pulses in a compensation cycle due to the limited polarization measurement rate, while the other part of the phase reference pulses are not measured. We show that Eve can control the phase noise by manipulating the polarization direction of the unmeasured phase reference to hide her attack on the quantum signal. Simulations show that Eve can obtain partial or total key rates information shared between Alice and Bob as the transmission distance increases. Improving the polarization measurement rate to 100% or monitoring the phase reference intensity in real-time is of great importance to protect the LLO CVQKD from polarization attack.

Experimental demonstration of high-rate discrete-modulated continuous-variable quantum key distribution system.

A high-rate continuous-variable quantum key distribution (CV-QKD) system based on high-order discrete modulation is experimentally investigated. With the help of the novel system scheme, effective digital signal processing (DSP) algorithms and advanced analytical security proof methods, the transmission results of 5.059 km, 10.314 km, 24.490 km, and 50.592 km are achieved for 1 GBaud optimized quantum signals. Correspondingly, the asymptotic secret key rates (SKRs) are 292.185 Mbps, 156.246 Mbps, 50.491 Mbps, and 7.495 Mbps for discrete Gaussian (DG) 64QAM, and 328.297 Mbps, 176.089 Mbps, 51.304 Mbps, and 9.193 Mbps for DG 256QAM, respectively. Under the same parameters, the achieved SKRs of DG 256QAM is almost same as ideal Gaussian modulation. In this case, the demonstrated high-rate discrete-modulated CV-QKD system has the application potential for high-speed security communication under tens of kilometers.

Effects of elevated air temperature coupling with soil drought on carbohydrate metabolism and oil synthesis during cottonseed development.

Cotton, as the fifth-largest oilseed crop, often faces the coupling stress of heat and drought. Still, the effects of combined stress on cottonseed oil synthesis and its closely related carbon metabolism are poorly investigated. To this end, experiments were conducted with two cultivars (Sumian 15 and PHY370WR) under two temperature regimes: ambient temperature (AT) and elevated temperature (ET, which was 2.5°C-2.7°C higher than AT) and three water regimes: optimum soil moisture (soil relative water content [SRWC] at 75% ± 5%), and drought (SD) including SRWC 60% ± 5% and SRWC 45% ± 5%, during 2016-2018. Results showed that ET plus SD decreased cottonseed kernel yield, seed index, kernel weight, and kernel percentage more than either single stress. The content of hexoses, the carbon skeleton source for oil synthesis, was decreased by ET while increased by SD. The combined stress increased the hexose content by increasing the activities of sucrose synthase (SuSy, EC 2.4.1.13) and invertase (Inv, EC 3.2.1.26) and upregulating GhSuSy expression; however, hexose content under combined stress was lower than that under SD alone. Increased oil content under SD was attributed to the high phosphoenolpyruvate carboxylase (PEPCase, EC 4.1.1.31), acetyl-CoA carboxylase (ACCase, EC 6.4.1.2), and diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) activities, whereas the opposite effects were seen under ET. Under combined stress, although ACCase activity decreased, PEPCase and DGAT activities, and GhPEPC-1 and GhDGAT-1 expression upregulated, enhancing carbon flow into oil metabolism and triacylglycerol synthesis, ultimately generating higher oil content.

Broadband laser chaos generation using a quantum cascade laser with optical feedback.

We propose a method to generate broadband laser chaos using a quantum cascade laser (QCL). Through numerical simulation, we give the evidence that the QCL with optical feedback can route to chaos through the quasi-periodic path. Furthermore, we investigate the influence of the feedback intensity and the bias current on the chaos bandwidth. Final results demonstrate that the chaos bandwidth can headily reach 43.1 GHz due to the lack of relaxation oscillation phenomena in QCLs.

Compact quantum random number generation using a linear optocoupler.

To date, various quantum random number schemes have been demonstrated. However, the cost, size, and final random bit generation rate usually limits their wide application on-shelf. To overcome these limitations, we propose and demonstrate a compact, simple, and low-cost quantum random number generation based on a linear optocoupler. Its integrated structure consists mainly of a light emitting diode and a photodetector. Random bits are generated by directly measuring the intensity noise of the output light, which originates from the random recombination between holes of the p region and electrons of the n region in a light emitting diode. Moreover, our system is robust against fluctuation of the operating environment, and can be extended to a parallel structure, which will be of great significance for the practical and commercial application of quantum random number generation. After post-processing by the SHA-256 algorithm, a random number generation rate of 43 Mbps is obtained. Finally, the final random bit sequences have low autocorrelation coefficients with a standard deviation of 3.16×10-4 and pass the NIST-Statistical Test Suite test.