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Developing an efficient catalyst for formic acid (FA) dehydrogenation is a promising strategy for safe hydrogen storage and transportation. Herein, we successfully developed trimetallic NiAuPd heterogeneous catalysts through a galvanic replacement reaction and a subsequent chemical reduction process to boost hydrogen generation from FA decomposition at room temperature by coupling Fermi level engineering with plasmonic effect. We demonstrated that Ni worked as an electron reservoir to donate electrons to Au and Pd driven by Fermi level equilibrium, and plasmonic Au served as an optical absorber to generate energetic hot electrons and a charge redistribution mediator. Ni and Au worked cooperatively to promote the charge heterogeneity of surface active Pd sites, leading to enhanced chemisorption of formate-related intermediates and eventually outstanding activity (342 mmol·g-1·h-1) compared with bimetallic counterpart. This work offers excellent insight into the rational design of efficient catalysts for practical hydrogen energy exploitation.

The quest for a universal method to shape the vesicular morphology in dynamic and diversified manners is a challenging topic of cell mimicry. Here we present a simple gas exchange strategy that can direct the deformation movements of polymer vesicles. Such vesicles are assembled by a class of gas-based dynamic polymers, where CO2 connects between the frustrated Lewis pair via dynamic gas-bridged bonds. Use of other competitive gases (N2O, SO2, or C2H4) to in situ exchange the CO2 linkages can change the polymer structure and drive the membrane to proceed with three fundamental movements, including membrane stretching, membrane incurvation, and membrane protrusion, thus remolding the shapes of polymersomes. The choices of gas types, concentrations, and combinations are crucial to adjusting the vesicle evolution, local change of membrane curvature, and anisotropic geometrical transformation. This will become a generalized strategy to control the vesicular polymorphism and deformable behavior.

Assembling bimetallic alloys (BAs) with metal-organic frameworks (MOFs) to form heterojunctions has emerged as a promising strategy for the construction of highly active electrocatalysts. However, the current approaches to prepare BA@MOF heterojunctions suffer from poor controllability. In this work, we report a fascinating method involving partial thermal reduction and galvanic replacement to induce CuPt growth on a CuHHTP MOF (HHTP= 2,3,6,7,10,11-hexahydroxytriphenylene) to construct a CuPt@CuHHTP heterojunction. The size of the CuPt nanoparticles can be effectively regulated by modifying the reduction temperature. The resultant CuPt NP@CuHHTP heterojunction nanoarrays exhibit high electrocatalytic activity and potential as an electrochemical H2O2 sensor with a low detection limit (5 nM), high sensitivity (6.942 mA·mM-1·cm-2), and outstanding selectivity. This in situ approach provides not only new insights into the preparation of BA@MOF-based heterojunctions but also an effective approach for the optimization of the catalytic performance of MOFs and related materials.

Background Although there are some existing data describing the usage of topiramate in patients with antipsychotic-induced obesity, study on its comparison with metformin is limited. This study aimed to explore the effectiveness and safety of concomitant topiramate on antipsychotic-induced obesity as well as its comparison with metformin. Methods 62 stabilized outpatients with antipsychotic-induced obesity were randomized into the topiramate group and the metformin group with 16-week treatment. The patients’ weight, body mass index (BMI), waist–hip ratio, and their side effects were assessed and compared. Intention-to-treat and completer analyses were performed. Meanwhile, covariance analysis was conducted to control the impact of the significant difference in BMI between the two groups. Results The two groups had comparable characteristics, though their difference in baseline BMI was significant. (1) Intention-to-treat analyses: the random missing values were replaced using the last observation carried forward method when intention-to-treat analyses were conducted. Compared with the baseline, the weight, BMI, and waist–hip ratio in the topiramate group markedly decreased at each follow-up, whereas, in the metformin group, only waist–hip ratio significantly decreased at 4 weeks after treatment. Compared with the metformin, only weight and BMI in the topiramate group were significantly decreased at week 4 after treatment, and at week 8–16, weight, BMI and waist–hip ratio were remarkably declined. (2) Completer analyses: compared with the baseline, the weight, BMI, and waist–hip ratio in the topiramate group at week 4–16 were markedly decreased, whereas only waist–hip ratio with metformin was significantly decreased at week 4. Compared with the metformin, all BMI with topiramate were markedly decreased at week 4–16. Moreover, its weight and waist–hip ratio also were notably lowered at week 8. No significant differences in adverse events were found between the two groups. Conclusions Topiramate, similar to metformin in reducing obesity as previously reported, also significantly reduced body weight, BMI, and waist–hip ratio in patients with antipsychotic-induced obesity and demonstrated well tolerance in psychiatric patients. Trialregistration The trial was registered at http://www.chictr.org.cn, and the number was ChiCTR-IPR-17013122.

Transition metal oxide/metal-organic framework heterojunctions (TMO@MOF) that combine the large specific surface area of MOFs with TMOs' high catalytic activity and multifunctionality, show excellent performances in various catalytic reactions. Nevertheless, the present preparation approaches of TMO@MOF heterojunctions are too complex to control, stimulating interests in developing simple and highly controllable methods for preparing such heterojunction. In this study, we propose an in situ electrochemical reduction approach to fabricating Cu

While prior studies of consumer preferences on electric vehicles (EVs) utilized stated preference (SP) or revealed preference (RP) data, this study examined consumer preferences for EVs through their online behaviour. Using big data and text mining technologies to explore large quantities of Chinese consumers’ online behaviour pertaining to EV selection, comparison, purchase inquiry, and comments, we found that EV prices, car classification and powertrain types were the most important factors influencing consumer response. In addition to general interests, we also noted application specific interests. For instance, we observed a preference for small battery electric vehicle (BEV) models with fast-charging batteries, which are well-suited to work commutes and daily life. By contrast, when examining plug-in hybrid electric vehicles (PHEVs), we noticed that consumers expressed a preference for sport utility vehicle (SUV) models. Finally, we found that in addition to price and technical specifications, EV aesthetics play a significant role in consumer choice. These conclusions are valuable for government agencies and EV manufacturers looking to promote EVs and address environmental pollution by appealing to consume interests.

Rice is the most important source of food worldwide, providing energy, and nutrition for more than half of the population worldwide. Rice grain quality is a complex trait that is affected by several factors, such as the genotype and environment, and is a major target for rice breeders. Cis-regulatory elements (CREs) are the regions of non-coding DNA, which play a critical role in gene expression regulation. Compared with gene knockout, CRE modifications can fine-tune the expression levels of target genes. Genome editing has provided opportunities to modify the genomes of organisms in a precise and predictable way. Recently, the promoter modifications of coding genes using genome editing technologies in plant improvement have become popular. In this study, we reviewed the results of recent studies on the identification, characterization, and application of CREs involved in rice grain quality. We proposed CREs as preferred potential targets to create allelic diversity and to improve quality traits via genome editing strategies in rice. We also discussed potential challenges and experimental considerations for the improvement in grain quality in crop plants.

Rice is the most important source of food worldwide, providing energy, and nutrition for more than half of the population worldwide. Rice grain quality is a complex trait that is affected by several factors, such as the genotype and environment, and is a major target for rice breeders. Cis-regulatory elements (CREs) are the regions of non-coding DNA, which play a critical role in gene expression regulation. Compared with gene knockout, CRE modifications can fine-tune the expression levels of target genes. Genome editing has provided opportunities to modify the genomes of organisms in a precise and predictable way. Recently, the promoter modifications of coding genes using genome editing technologies in plant improvement have become popular. In this study, we reviewed the results of recent studies on the identification, characterization, and application of CREs involved in rice grain quality. We proposed CREs as preferred potential targets to create allelic diversity and to improve quality traits via genome editing strategies in rice. We also discussed potential challenges and experimental considerations for the improvement in grain quality in crop plants.

Orchestrating conflicting polymerization mechanisms in a single polymerization process through one external stimulus is a prerequisite to achieve in-situ selective synthesis of different monomers. Here we report an electrochemically controlled mechanism transformation that enables selective activation of living cationic or radical polymerization via an alternating voltage and dual electrocatalysts. Using identical mixed-monomer condition, a variety of desired block copolymer structures, including diblock, multiblock, random, and tapered copolymers can be obtained by simply varying the periods or phases of the alternating potential. Moreover, merging this electro-interconverted polymerization with a flow-chemistry technique can streamline preparation of functional polymer materials with complex multiblock structure. This study would offer a new vision on large-scale electrochemical synthesis of sequence-defined polymers.

Copolymerization of a trifluoromethyl ketone-bearing monomer and a rhodamine monomer has led to the formation of peroxynitrite (ONOO−) signaling molecule-responsive polymer fluorescent micelles. Even with only 10−9 M of endogenous ONOO−, it can activate micellar disassembly, quantitatively illuminating nanoparticle fluorescence for mapping intracellular ONOO−.

Implant-mediated targeted drug delivery without an external magnetic field is very challenging. In this work, we report targeted nanodrug delivery initiated by a Fe3O4/poly(lactic-co-glycolic acid) implant scaffold with high magnetism. The implant scaffold is biocompatible and durable. It effectively attracts nanodrugs to its surface, thus killing cancer cells. These findings provide a proof of concept for the magnetic implant-directed nanodrug targeting without the need for an external magnetic field. This approach may further facilitate more precise medical treatments.

We report on the state of the art and future prospects and challenges of optical access networks. Details on a recent field demonstration of a novel tunable WDM-PON system with novel T-SFP+ modules will be presented. Furthermore, the concept of centralized wavelength control of the optical network unit wavelengths will be explained as well as different realization options of pilot-tone based communication channels. Finally, a control concept for tuning the DS-DBR laser will be shown.

This paper reports an uncooled transmitter system using a digital super-mode (DS) distributed Bragg reflector (DBR) tunable laser, which is able to act as an athermal, wavelength agnostic transmitter suitable for wavelength division multiplexed (WDM) passive optical network (PON) applications. An open-loop laser current control algorithm is designed to compensate autonomously for wavelength drift, thus allowing constant operating wavelength to be achieved regardless of ambient temperature. An improved wavelength accuracy of ±3 GHz is achieved when using low bandwidth feedback from the central office using information from a centralized shared wavelength locker. The entire laser start-up, channel selection and subsequent wavelength control is autonomous and has been implemented on micro-controllers and field programmable gate arrays. We demonstrate a three channel WDM-PON system comprising an uncooled packaged DS-DBR laser in the presence of two neighboring interfering channels. Error free transmission over 40 km single mode fiber of 10 Gb/s externally modulated NRZ data, is achieved for each of 48 C-band channels on the 100 GHz ITU grid. Successful athermal operation is demonstrated by sweeping the ambient temperature of the laser from 15 to 70 °C with a maximum wavelength deviation for any channel of no more than 0.1 nm.

A low sidelobe level time-domain adaptive broadband beamforming is proposed in this paper by adding a sparse constraint on the output beam pattern. Then, the robustness against direction of arrival (DOA) mismatch can be achieved. The proposed method is a convex optimization problem, which can be solved by convex optimization software efficiently. Simulation and experimental results show the properties of sidelobe suppression and robustness against DOA mismatch by comparing with the worst-case performance optimization (RB-RI-WC) algorithm.

A range sidelobe suppression method is proposed for frequency diverse multiple-input multiple-output (FD-MIMO) sonar imaging. Unlike traditional methods which suppress cross-correlation functions (CCFs) between transmitting waveforms as low as possible, we use band overlapped frequency diverse continuous wave (FDCW) pulses to obtain relatively high CCFs. We point out that these relatively high CCFs can fill the band gap between auto-correlation functions (ACFs) between neighboring FDCW pulses, thereby showing an ability of reducing the spectrum leakage. Furthermore, we apply an amplitude weight vector to these FDCW pulses to further reduce the spectrum leakage and hence, produce much low range sidelobes. Via theoretical analyses and numerical simulations, we show that the proposed method can produce a high-resolution range profile as well as a low range sidelobe level.

Low frequency noise is the main noise sources of wind turbine, causing annoyance for daily life. This paper proposes a simplified model for wind turbine low frequency noise sources through three elements: noise sources, propagation paths and perceived signals of acoustic vector sensors(AVS) array. AVS array is utilized for far field source localization, offering a key advantage with respect to conventional acoustic pressure solutions due to their vector nature. Due to doppler effects, time-dependent Green functions are hereby used to extract information about the physical characteristic of different elements. Two time domain beamforming methods (de-dopplerized and conventional method) are utilized for locating the model noise rotational sources with AVS array, along with several simulations and their performance analysis in different situations. The results show that de-dopplerized method outperform than the conventional method.

A high angle and range resolution imaging method using a double-ping frequency diverse multiple-input multiple-output (MIMO) sonar is proposed. The proposed MIMO sonar is composed of a uniform linear array (ULA) and two transmitting elements located at the two ends of the receiving ULA. The interelement spacing of the two transmitting elements is equal to the produce of the inter-element spacing and the element number of the receiving ULA. We show that such array configuration is able to ensure a high angle resolution without increasing the array physical size. At the same time we use a pair of frequency diverse linear frequency modulation (FD-LFM) pulses to achieve a high range resolution. Based on the array configuration and the transmitting waveforms, we give the double-ping signal transmitting mode and the echo processing procedure. Via numerical simulations we show that the proposed double-ping MIMO sonar imaging method can improve the angle and range resolutions simultaneously.

A source localization based on sparse spectral fitting and spatial matrix filtering is proposed in this paper to localize the multiple targets which are closely spaced in the strong interference environment. Comparing with the traditional methods, the properties of interference suppression and high resolution of localization are verified by simulation and experimental results.

We demonstrate a 3×10Gb/s uncooled MIMO DWDM system using uncooled DFB lasers with real-time crosstalk cancellation, allowing separate lasers to operate at different temperatures. Adaptive laser bias control is applied to ensure adequate channel separation.

We describe the performance of an optimized high-temperature DS-DBR laser used as an uncooled WDM source. Constant wavelength output with less than 6GHz error without mode-hopping is shown for C-band channels from 70-90 °C.

A proof-of-principle demonstration of a multiple input-multiple output (MIMO) dense wavelength division multiplexing (DWDM) system is reported. It uses standard uncooled distributed feedback (DFB) lasers with intensity modulation-direction detection (IM-DD), in which the temperature of each laser is allowed to drift independently within a 50°C temperature range. A feedback-based laser bias control algorithm is introduced to guarantee acceptable wavelength spacing and a post-photodetection minimum mean square error (MMSE) decoder is applied to cancel the inter-channel crosstalk. The relative sensitivity of the MIMO receiver in both a random laser temperature drift scenario and a worst case scenario are investigated by simulations in MATLAB. Experimental results for a 40-channel × 12.5 Gb/s DWDM system transmitting over 28 km of single-mode fiber with worst possible wavelength distribution prove the feasibility of the technique.