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The cognitive symptoms of schizophrenia are wide ranging and include impaired goal-directed action. This could be driven by an increase in dopamine transmission in the dorsomedial striatum, a pathophysiological hallmark of schizophrenia. Although commonly associated with psychotic symptoms, dopamine signalling in this region also modulates associative learning that aids in the execution of actions. To gain a better understanding of the role of subcortical dopamine in learning and decision-making, we assessed goal-directed action in male mice using the cross-species outcome-specific devaluation task (ODT). First, we administered systemic amphetamine during training to determine the impact of altered dopaminergic signaling on associative learning. Second, we used pathway-specific chemogenetic approaches to activate the dorsomedial and ventral striatal pathways (that originate in the midbrain) to separately assess learning and performance. Amphetamine treatment during learning led to a dose-dependent impairment in goal-directed action. Activation of both striatal pathways during learning also impaired performance. However, when these pathways were activated during choice, only activation of the ventral pathway impaired goal-directed action. This suggests that elevated transmission in the dorsomedial striatal pathway impairs associative learning processes that guide the goal-directed execution of actions. By contrast, elevated transmission of the ventral striatal pathway disrupts the encoding of outcome values that are important for both associative learning and choice performance. These findings highlight the differential roles of the dorsomedial and ventral inputs into the striatum in goal-directed action and provides insight into how striatal dopamine signaling may contribute to the cognitive problems in those with schizophrenia. • Goal-directed action may be impaired in schizophrenia due to altered dopamine transmission in the dorsomedial striatal pathway, a mechanism which can be explored using animal models. • Systemic administration of amphetamine in male mice during instrumental learning, which predominantly alters brain dopamine levels, impaired goal-directed action. • Chemogenetic activation of separate midbrain inputs into dorsomedial and ventral striatum during learning impaired goal-directed action. • Chemogenetic activation of these same pathways during choice had differential outcomes. Only activation of the ventral striatal pathway impaired goal-directed action. • This study indicates that dopamine and dorsomedial striatal pathway activation may play a role in learning and goal-directed action impairments relevant to schizophrenia. [ABSTRACT FROM AUTHOR]

• Aerodynamic characteristics of a typical high-speed railway viaduct under tornado near-ground winds were studied. • Surface pressure coefficients of the bridge deck vary from place to place within the tornado. • Largest side and lift forces occur at the tornado core, but the change patterns of forces in different types with the variation distance. • Research findings are helpful for the design, operation & maintenance of high-speed railway bridges. The tornado is in direct contact with the underlying surface, which causes damage and indicates the vortex structure close to the ground. Accordingly, the maximum wind velocity generally could occur near the ground, potentially exposing the infrastructure to higher wind loads. However, one of the biggest challenges facing tornado research is characterizing the wind structure very near the surface due to the limitation of the data by using Doppler weather Radar. Considering the advantage of the high-fidelity computational fluid dynamics (CFD) models, this study aims to investigate the aerodynamic characteristics of a high-speed railway viaduct under tornado near-surface winds. More specifically, in light of limited full-scale data to arrive at a consensus on quantifying key parameters characterizing the tornado flow and near-surface winds, firstly. Secondly, tornado radar-measured data and a theoretical analysis model were utilized to validate the accuracy of the numerical method adopted in this study. Thirdly, the wind pressure distribution on the bridge is validated using the wind tunnel experimental data in Central South University(CSU), and the comparison between the simulational bridge and the measured data under crosswind was satisfactory. Finally, a comprehensive modeling strategy comprehensively investigates the aerodynamic characteristics of a high-speed railway viaduct under a tornado near-surface wind. [ABSTRACT FROM AUTHOR]

[Display omitted] • A more economical utilization mode of K 2 FeO 4 pretreatment was explored. • Alkaline K 2 FeO 4 pretreatment can effectively increase SCFAs yield. • Effect of pH regulated K 2 FeO 4 pretreatment on phosphorous leaching was analyzed. • A recovery strategy of carbon and phosphorus in sludge was put forward. To improve the dose efficiency of K 2 FeO 4 in waste activated sludge (WAS) treatment, pH regulation on K 2 FeO 4 pretreatment and acidogenic fermentation was investigated. Four pretreatments were compared, i.e. pH3 + 50 g/kg-TS, pH10 + 50 g/kg-TS, neutral pH + 50 g/kg-TS and neutral pH + 100 g/kg-TS (without pH adjustment). The higher short chain fatty acids (SCFAs) yield and phosphorous dissolution rate was found under the condition of pH 10.0. In pH10 + 50 g/kg-TS, the maximum concentration of SCFAs was 5591 mg-COD/L, which yield was 22.6 times higher than that of the neutral pH + 50 g/kg-TS (237 mg COD/L). The acidogenic fermentation period could be shortened to 5 days and acetic acid accounted for 70 % of SCFAs. Furthermore, PO 4 3--P in the hydrolysate (346.5 mg/L) accounted for 47.59 % of TP, which is easier to be recovered by chemical precipitation. Therefore, a more economical and feasible utilization mode of potassium ferrate was proposed. [ABSTRACT FROM AUTHOR]

• The slipstream of the CR400 high-speed train is experimentally investigated by a moving train rig. • Measured by a point cloud of 25-locations, the ensemble-averaged profiles, spatial variations, gusts, and time–frequency characteristics of the slipstream were analyzed. • The spatial–temporal variation in the properties of flow around the head car has been explained regarding the shape of the train. This paper experimentally investigates the characteristics of the velocity field induced by the slipstream from the leading carriage model of a CR 400 high-speed train. The tests were carried out using a 1:16.8 scale model on a moving model rig developed at the Central South University, PRC. The slipstream velocity field was measured at a point cloud involving 25 locations on a plane orthogonal to the track orientation. Aiming at understanding the slipstream ensemble characteristics, especially those unique to the CR400 train, observations were analyzed to evaluate the ensemble-averaged profiles, spatial variations, gusts and time–frequency characteristics of velocity fluctuations in the slipstream. The results suggest that the moving train model and testing rig used in this study capture the unsteady and time-variant features of the slipstream. The spatiotemporal profile of the slipstream usually includes a primary and a secondary peak at the nose tip and the region immediately next to it, respectively. Among the collection of locations studied, the primary peak reaches its maximum at a lateral location close to the train side at the nose height. Finally, the time–frequency portraits of the spatiotemporal variations of the slipstream were obtained using wavelet scalograms of the velocity field, which offered an insightful understanding of the various scales of velocity fluctuations around the nose and their locale. [ABSTRACT FROM AUTHOR]

[Display omitted] • Identified current situation and challenges of high-speed railway aerodynamics. • Aerodynamics of train, bridge, train-bridge system and their factors are discussed. • In-depth review of wind tunnel testing for train, bridge, and train-bridge system. • Discussed limitations of existing experiments and tendencies in applications. • Proposed and developed some platforms for aerodynamic issues of train-bridge system. Wind tunnel tests have been widely applied in aerodynamic investigations owing to their unique advantages. However, it is difficult to theoretically establish a simplified symmetry or two-dimensional model because of the relative motion of the structures and proximity of the train to the ground/infrastructure. Additionally, railway-related aerodynamic problems tend to be more challenging than those encountered in other engineering structures. Moreover, transient and crosswind effects, as well as complex operation environments, need to be considered, thereby making aerodynamic analyses of train–bridge systems challenging. Advanced manufacturing methodologies can reproduce realistic scenarios of high-speed train (HST) operations in a wind tunnel. The development of a controllable and affordable experimental method presents considerable research opportunities and challenges. There exists a strong correlation between wind tunnel experimental methods and the understanding of aerodynamic mechanisms, and some wind tunnel tests are dedicated to identifying the aerodynamic behavior using specific test systems. This study mainly describes the types of tests typically performed in a wind tunnel to analyze the aerodynamic issues of train–bridge systems under wind action. To identify and understand the individual role of the above mentioned-correlated systems, trains and bridges in wind tunnel tests are described separately. High-speed trains on bridges must be made safe and environmentally friendly, and a few cases are presented as indications to reconsider our aerodynamic research priorities. Thus, advanced experimental activities have been proposed in the Central South University (CSU) wind tunnel, representing helpful practices in defining the real-world aerodynamic behavior of wind-vehicle-bridge systems. [ABSTRACT FROM AUTHOR]

Motivated by the inevitable trend of the Internet of Everything, human-machine interaction technology has gradually been permeated into people's daily life. Receptive devices that capture human behaviors and responsive devices that provide machine feedback are key components of human-machine interface. While it is a great challenge to integrate receptive and responsive devices in a well-organized way due to the limitations of material properties and device structures. In this work, we investigate the formation of laser-induced graphene on Nomex paper and propose an efficient interactive strategy based on its piezoresistive and thermoacoustic effects. Functional integration of receiving instructions (pressure-sensing capability) and providing feedback (sound-emitting capability) can be achieved by simply assembling three layers of Nomex paper that have been laser-customized on both sides. The integrated device not only has a sensitive response (∼12 relative current change and ∼50 ms response time) to the pressure similar to a gentle finger press (∼10 kPa), but also can emit a high-quality sound signal with larger sound pressure levels (∼70 dB at 1 W/cm2 power density). Furthermore, two proof-of-concept demonstrations, a press-to-audio pad and a command-responding thermo-earphone, are presented to substantiate the feasibility in information exchange activities. [Display omitted] • Laser-induced graphene layers with favorable electrical conductivity are formed on Nomex paper. • Different conductive properties between double-sided laser-induced graphene across Nomex substrate are obtained by regulating laser power. • Pressure-sensing and sound-emitting capabilities are realized taking advantage of piezoresistive and thermoacoustic effects of laser-induced graphene. • Multifunctional integration is implemented by assembling three-layer Nomex paper that feature double-sided laser-induced graphene. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar accelerated the initiation of methanogenesis and increase methane yield. • Increment of methane yield decreased from 60.6% to 10.4% when increase TS from 5% to 14%. • ARGs reduction was closely associated to the decreased abundance of Proteobacteria. • ARGs abundance in liquid phase was significantly reduced in biochar group. Effects of biochar on co-digestion of pig manure and dewatered sewage sludge under different total solids (TS) were investigated. Biochar could accelerate the start-up of methanogenesis and shorten the adaptation phase. At TS5%, the methane daily production in biochar group was 60.6% higher than the control; nevertheless, when TS increased, the gap between two groups gradually narrowed. Additionally, the change on antibiotics resistance genes (ARGs) was also affected by TS and the biochar addition. Moreover, biochar was beneficial to reduce ARGs in liquid phase. At TS14%, the total ARGs abundance in the liquid phase of biochar group was 41.4% lower than the control, among which the reduction rates of etB(P), sul1, rpoB2, macA, mupA and mupB were more prominent. These findings could provide useful guidance for developing ARGs elimination strategy before their release into the environment. [ABSTRACT FROM AUTHOR]