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Generally, in terms of electrocatalytic CO2 reduction, single‐atom catalysts show high selectivities yet low current densities whereas conventional nanoparticle catalysts exhibit relatively high current densities but low selectivities. This work combines the advantages of the two classes of catalysts by constructing a Ni‐Gd‐N‐doped carbon black electrocatalyst within which NiI active sites are exposed outside the carbon layers and Ni nanoparticles are encapsulated inside the carbon layers. The Gd atoms can not only influence the local electron densities of Ni 3d orbitals, thus strengthening the electronic activity, but also tailor the sizes of the Ni nanoparticles, thereby minimizing the activity toward hydrogen evolution. Accordingly, this electrocatalyst yields both a high CO faradaic efficiency (97 %) and a large current density (308 mA cm−2), alongside an outstanding stability (100 h). [ABSTRACT FROM AUTHOR]

Mechanical metamaterials are of tremendous research interest due to their unconventional properties that arise from unit microstructure. Shape‐reconfiguration is an effective method to realize programmability on various properties for different tasks of a structure or system, while existing researches focus on multiple degree‐of‐freedom (DOF) systems or limited configurations that morph along a single kinematic path. Here, starting from a one‐DOF Wohlhart polyhedron module, its interesting topological transformation is explored along multiple motion paths through kinematic bifurcations, accompanied by tunable mechanical properties, including Poisson's ratio, chirality, and stiffness. Furthermore, these modules are tessellated into 3D metamaterials to harness their reconfigurability to independently program the Poisson's ratios in orthogonal planes within a wide range of negative Poisson's ratio, positive Poisson's ratio, and even zero Poisson's ratio. This work opens up avenues for the design of programmable metamaterials based on the perspective of kinematic bifurcation generating from single DOF systems, which can readily be applied in shape‐morphing systems in various fields, such as flexible metamaterials, morphing architectures, and deployable structures. [ABSTRACT FROM AUTHOR]

The bacterial diversity of salted mackerel "one‐night courtyard" at soft frozen area (−7℃–0℃) storage was studied. The fish samples at 0, 14, 21, 28, and 35 days were analysis for bacterial structure using high‐throughput sequencing technologies (HTS) and biogenic amines using high‐performance liquid chromatography (HPLC). The analysis results of HTS showed that the dominant bacteria species was varied gradually following with storage time. On the 0th, 21st, and 28th days of storage, dominant Vibrionaceae was accounting for 71.70%, 59.16%, and 70.68% of the total sequences analyzed, respectively. On the 14th and 35th days, Shewanellaceae was the dominant bacterial, accounting for 87.53% and 70.95% of the total sequences analyzed, respectively. In addition, 21st and 28th days, an abundance of Operational Taxonomic Units (OTUs) was top. The dominant bacterial of Proteobacteria, Firmicutes, was producer of biogenic amines. Furthermore, the analysis results of HPLC shown the total biogenic amines of maximum amount 363.01 mg/kg in the sample of HY.14 lower than 1000 mg/kg of the FDA regulation. The range ability of cadaverine was obvious following with the storage time. Cadaverine was 87.36 mg/kg on the 0th day, and it was maximum amount of 276.89 mg/kg on the 14th days. Putrescine was 20 mg/kg on the 0th day and maximum amount of 55.04 mg/kg on the 28thdays of storage. The tyramine was smallest amount of production, and the largest amount was 38.99 mg/kg on 28th, and the smallest amount was 11.97 mg/kg on 35th. Nevertheless, the maximum amount of histamine was 55.04 mg/kg on the 0th day and about 23.14 mg/kg of histamine was little change from 14th to 35th days of storage. Dominant bacteria affect the change of biogenic amines. The study can help understand the interaction between microbial flora and biogenic amines in the salted mackerel of one‐night courtyard. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a multi-system neurodegenerative disorder. Patients with PD often suffer chronic pain. In the present study, we investigated motor, sensory and emotional changes in three different PD mice models. We found that 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treatment caused significant changes in all measurements. Mechanical hypersensitivity of PD model induced by MPTP peaked at 3 days and persisted for at least 14 days. Using Fos transgenic mice, we found that neurons in the anterior cingulate cortex (ACC) were activated after MPTP treatment. Inhibiting ACC by bilateral microinjection of muscimol significantly reduced mechanical hypersensitivity and anxiety-like responses. By contrast, MPTP induced motor deficit was not affected, indicating ACC activity is mostly responsible for sensory and emotional changes. We also investigated excitatory synaptic transmission and plasticity using brain slices of MPTP treated animals. While L-LTP was blocked or significantly reduced. E-LTP was not significantly affected in slices of MPTP treated animals. LTD induced by repetitive stimulation was not affected. Furthermore, we found that paired-pulse facilitation and spontaneous release of glutamate were also altered in MPTP treated animals, suggesting presynaptic enhancement of excitatory transmission in PD. Our results suggest that ACC synaptic transmission is enhanced in the animal model of PD, and cortical excitation may play important roles in PD related pain and anxiety. [ABSTRACT FROM AUTHOR]

• A new fluorescent probe DIC was designed baed pn cumarin-based. • DIC could sensitively sense alkaline pH with the pKa value of 8.12. • DIC exhibited excellent photostability and reversibility in the pH detection. • DIC was employed for in-suit tracking of pH fluctuations in living zebrafish. A coumarin-based fluorescent probe DIC (3-(2-(5-(4-(diphenylamino)phenyl)isoxazol-3-yl)-1-hydroxyvinyl)-7-hydroxy-2H-chromen-2-one) with high performance was exploited for detecting pH changes in biological system and food samples. The probe DIC could sensitively sense alkaline pH fluctuations in the range of 6.50‒9.98 with the pKa value of 8.12 through a remarkable fluorescence turn-on process. The probe DIC exhibited excellent photostability and reversibility in monitoring the pH fluctuations. The detection mechanism of DIC for pH was confirmed by 1H NMR titration experiment and theoretical calculation. This probe owned a low cytotoxicity and was successfully employed for in-suit tracking of pH fluctuations in living zebrafish. In addition, the probe DIC could be applied in the visualization of meat and prawn freshness. [Display omitted] [ABSTRACT FROM AUTHOR]

A nuclear heating system integrated with a heat storage tank (HST-NHS) is a promising technical solution for countries with large-scale heating demand. HST-NHS can greatly curtail carbon dioxide emissions and contribute to sustainable development. Appropriate control strategies are not only crucial to realize the real-time matching between HST-NHS heat supply and heat demand, but also ensure the stable and safe operation of HST-NHS. Until now, control strategies for HST-NHS have received limited attention. A refined dynamic simulation model for HST-NHS is established based on APROS software. The verification of the built model in steady state and transient state is completed. Two basic control strategies for the primary heating network (PHN) of HST-NHS, constant supply water temperature and variable flow rate (CT-VF) and variable supply water temperature and constant flow rate (VT-CF) are presented in detail. Based on various typical working conditions of a central heating region in Liaoyuan City, the control effects of two control strategies are investigated. Additionally, a comprehensive performance comparison between the two strategies is explored. Simulation results indicated that under the two control strategies, the indoor temperature can be effectively controlled at a high comfort level. During the same typical day, the total energy consumption cost under the VT-CF control strategy is 0.5 × 105 yuan lower than that under the CT-VF control strategy. • Dynamic model of nuclear heating system with heat storage is developed. • The verification of the built model in steady and transient state is completed. • Control effects of two basic control strategies during typical days are evaluated. • A performance comparison of two basic control strategies is conducted. [ABSTRACT FROM AUTHOR]

Clean energy conversion/storage techniques have become increasingly significant because of the increasing energy consumption. Regarding practical applications like zinc-air batteries and supercapacitors, electrode materials are essential and often require both porous networks and active species to enhance their electrochemical performance. Nitrogen-doped porous carbon (NPC) is a kind of promising material, which provides efficient active sites and large surface areas for energy conversion/storage applications. However, rational modulation of properties for maximizing NPC performance is still a challenge. Herein, a promising NPC material derived from natural biomass is successfully synthesized by following a stepwise preparation method. Physisorption and X-ray photoelectron spectroscopy (XPS) analyses demonstrate both pore structures and nitrogen species of the NPC have been delicately tuned. The optimized sample NPC-800-m exhibits excellent performance in both oxygen reduction reaction (ORR) and three-electrode supercapacitor measurement. Moreover, the homemade zinc-air battery and symmetric supercapacitor assembled with NPC-800-m also display outstanding energy and power density as well as durable stability. Density functional theory (DFT) calculations further confirm the synergistic effects among graphitic, pyridinic and pyrrolic nitrogen. The existence of multispecies of nitrogen combined with the optimized pore structure is the key to the high electrochemical performance for NPC-800-m. This work not only provides feasible and green synthetic methodology but also offers original insights into the effective pores and the synergistic effects of different nitrogen species in the NPC materials. [ABSTRACT FROM AUTHOR]

The Anti-pitching Generating WEC (AG-WEC) combines the floating articulated platform with the wave energy device. The wave energy device is installed between the hinged platform modules to provide damping to reduce the relative pitch while generating electricity at the same time. A semi-analytical solution of the dynamic characteristics of the AG-WEC is developed by the frequency- and time-domain analysis of the device based on the potential flow theory. Based on Eigenfunction Expansion Matching's potential flow theory, the semi-analytical expressions of wave loads and radiation hydrodynamic coefficients of AG-WEC are derived. By establishing a two-degree-of-freedom vibration system, the analytical solution of frequency-domain dynamic characteristics of the AG-WEC is obtained. Based on the analytical solution of Optimal PTO Damping Coefficient, the analytical optimization of the PTO system is realized, and the mechanism of high-efficiency energy capture of the device is revealed. The time-domain dynamic characteristics of AG-WEC under regular and irregular waves are analyzed by introducing the non-linear Power Take-Off (PTO) system and irregular wave theory with combining the Impose Response Function method. [ABSTRACT FROM AUTHOR]

A T-S fuzzy model with two rules is established to exactly describe the nonlinear uncertain heave dynamics of underwater vehicles with bounded heave speed. A single linear-matrix-inequality-based (LMI-based) state feedback controller is then synthesized to guarantee the global stability of the depth control system. Simulation results verify the effectiveness of the proposed approach in comparison with linear-quadratic regulator (LQR) method. Nonlinear disturbance observer is appended to the system when the underwater vehicles are affected by the gravity-buoyancy imbalance. The two-stage control method is effective to stabilize an uncertain system with both parameter uncertainties and external disturbances. [ABSTRACT FROM AUTHOR]

Electronic health records (EHR) are rich heterogeneous collections of patient health information, whose broad adoption provides clinicians and researchers unprecedented opportunities for health informatics, disease-risk prediction, actionable clinical recommendations, and precision medicine. However, EHRs present several modeling challenges, including highly sparse data matrices, noisy irregular clinical notes, arbitrary biases in billing code assignment, diagnosis-driven lab tests, and heterogeneous data types. To address these challenges, we present MixEHR, a multi-view Bayesian topic model. We demonstrate MixEHR on MIMIC-III, Mayo Clinic Bipolar Disorder, and Quebec Congenital Heart Disease EHR datasets. Qualitatively, MixEHR disease topics reveal meaningful combinations of clinical features across heterogeneous data types. Quantitatively, we observe superior prediction accuracy of diagnostic codes and lab test imputations compared to the state-of-art methods. We leverage the inferred patient topic mixtures to classify target diseases and predict mortality of patients in critical conditions. In all comparison, MixEHR confers competitive performance and reveals meaningful disease-related topics. Electronic Health Records (EHR) are subject to noise, biases and missing data. Here, the authors present MixEHR, a multi-view Bayesian framework related to collaborative filtering and latent topic models for EHR data integration and modeling. [ABSTRACT FROM AUTHOR]