Experimental Platform For Research Research Articles

Optimization and verification of conditions for induction of neutrophil extracellular traps in vitro

This study aims to optimize the conditions for the formation of neutrophil extracellular traps(NETs) in vitro, so as to establish a relatively stable experimental research platform. Different conditions were compared, including commonly used laboratory animals(rats and mice) and a variety of cell sources(bone marrow neutrophils and peripheral blood neutrophils separated by percoll density gradient centrifugation). Different inducers like lipopolysaccharide(LPS) and phorbol 12-myristate 13-acetate(PMA) were used for induction in vitro. Myeloperoxidase(MPO)/citrullinated histone H3(CitH3)/DAPI immunofluorescence and cell free DNA(cf-DNA) content determination were used for comprehensive evaluation to screen the optimal conditions for the formation of NETs induced in vitro. Furthermore, the stability of the selected conditions for inducing the formation of NETs in vitro was evaluated by tetramethylpyrazine(TMP), an active component in Chinese herbal medicines. The results showed that coated poly-D-lysine(PDL) induced the formation of NETs in bone marrow neutrophils of mice to a certain extent. Both LPS and PMA significantly up-regulated the protein levels of MPO and CitH3 in mouse bone marrow neutrophils and elevated the cfDNA level in the supernatant of rat peripheral blood neutrophils. The cfDNA level in the PMA-induced group increased more significantly than that in the LPS-induced group(P<0.05). The results of immunofluorescence staining showed that the expression of MPO and CitH3 in mouse bone marrow neutrophils, rat bone marrow neutrophils, and rat peripheral blood neutrophils were significantly increased after PMA induction, especially in rat peripheral blood neutrophils. TMP significantly down-regulated the protein levels of MPO, CitH3, and neutrophil elastase(NE) in rat peripheral blood neutrophils induced by PMA. In conclusion, treating the peripheral blood neutrophils of rats with PMA is the optimal condition for inducing the formation of NETs in vitro. This study provides an optimal platform for in vitro studies based on NETs and a basis for studying the effects of traditional Chinese medicines targeting NETs.

Biological culture module for plant research from seed-to-seed on the Chinese Space Station

The long-term cultivation of higher plants in space plays a substantial role in investigating the effects of microgravity on plant growth and development, acquiring valuable insights for developing a self-sustaining space life supporting system. The completion of the Chinese Space Station (CSS) provides us with a new permanent space experimental platform for long-term plant research in space. Biological Culture Module (GBCM), which was installed in the Wentian experimental Module of the CSS, was constructed with the objective of growing Arabidopsis thaliana and rice plants a full life cycle in space. The techniques of LED light control, gas regulation and water recovery have been developed for GBCM in which dry seeds of Arabidopsis and rice were set in root module of four culture chambers (CCs) and launched with Wentian module on July 24, 2022. These seeds were watered and germinated from July 28 and grew new seeds until November 26 within a duration of 120 days. To this end, both Arabidopsis and rice plants completed a full life cycle in microgravity on the CSS. As we know, this is the first space experiment achieving rice complete life cycle from seed-to-seed in space. This result demonstrates the possibility to cultivate the important food crop rice throughout its entire life cycle under the spaceflight environment and the technologies of GBCM have effectively supported the success of long-term plant culture experiments in space. These results can serve as invaluable references for constructing more expansive and intricate space plant cultivation systems in the future.

Comprehensive investigation of the electro-thermal performance and heat transfer mechanism of battery system under forced flow immersion cooling

Efficient cooling during rapid battery charging/discharging necessitates forced circulating flow in immersion cooling systems. However, under forced flow immersion cooling (FFIC), the comprehensive impact on the electrical and thermal performance of battery modules remains inadequately explored. This study constructs an immersion-cooled battery module test platform for experimental research on the evolution of electrical and thermal characteristics. The results show that under FFIC, when the depth of discharge (DOD) during 2C and 3C discharges is below 85 %, the voltage deviation of module (δU,t) remains stable within 1 % and 2 %, respectively. At DOD of 100 %, the maximum δU,t for 2C and 3C are 10 % and 24.5 %, respectively. Furthermore, the analysis of Pearson correlation coefficient under FFIC reveals that the δU,t exhibits a very strong positive correlation with temperature difference of battery module and cell, with correlation coefficients of +0.94 and + 0.87, respectively. Higher flow rates accelerate the recovery of module temperature and facilitate voltage distribution equalization after discharge. Additionally, to elucidate the influence of flow rate on FFIC, module-scale heat transfer characteristics during battery discharge are theoretically analyzed, establishing a fitting relationship between C-rates, flow rates, and the Nusselt number (Nu). This study provides a comprehensive understanding of integrated electro-thermal performance and external heat transfer capability for flow regulation in immersion cooling.

Visual exploratory activity in elite women’s soccer: an analysis of the UEFA Women’s European Championship 2022

ABSTRACT Recent research has developed understanding of the technical and tactical determinants of success in elite women’s soccer, however a lack of research exists on analysing how elite female players visually explore their environment to support skilled soccer performance. This study aimed to describe the visual exploratory activity (VEA) of elite female central midfield players and understand the relationships between VEA, performance with the ball and specific contextual and situational factors. Thirty female central midfield players (M age = 26.7 years, SD = 3.8) from the eight teams who competed in the knock-out stages of UEFA Women’s European Championship 2022 were analysed. Television broadcast and UEFA tactical footage were combined to analyse players across the seven knock-out stage matches, totalling 1,038 individual ball possessions. The mean scan frequency before receiving the ball was 0.35 scans/second. Results showed pitch location when receiving the ball to be the main predictor of scan frequency, which in turn predicted action result (p = 0.003) and turn with the ball (p = 0.003). Scan frequencies were lower compared to men’s elite and academy players. This study sets a platform for experimental research to further our understanding of VEA and performance with the ball in women’s soccer.

Mecanum wheel mobile platform for rapid prototyping of the autonomous control algorithms

This article describes the author’s design of the Mecanum wheel mobile robots (MWR), which can be used as a test platform for experimental research into the development and implementation of autonomous systems. The paper contains a literature review of the subject matter and describes the mechanical actuator subsystem and electronic and information subsystem of the mobile robot solution. The robot was navigated using a minicomputer equipped with a Jetson Nano chip. The robot’s navigation system was implemented using the ROS environment through high-level software. Software modularity is desirable in circuits intended for research and rapid prototyping. This allows for easier modification and maintenance. The microcontroller has been implemented with a DC drive control system and incremental encoder support to estimate robot position using odometry. The project utilizes the Jetson Nano for processing data from distance sensors and monitoring the robot’s performance. The mobile platform is equipped with a RGB-D camera (Microsoft Kinect 360), the robot can use this to perform 3D mapping of the environment. A LiDAR sensor is used to collect data from a two-dimensional space. Laboratory tests were carried out to test the validity of the solutions adopted in the design of the Mecanum-wheeled mobile robot’s navigation system configuration.

Near forward scattering light of planar film target driven by broadband laser

Laser plasma interaction (LPI) has always been an important research topic in the ignition phase of inertial confinement fusion (ICF). Over the years, researchers have attempted to use various laser beam smoothing schemes and optimized light source solutions to suppress the development of LPI. Among them, low-coherence laser drivers have attracted widespread attention in the fields of laser-plasma physics and laser technology in recent years. Recently, a broadband second harmonic laser facility named “Kunwu” has provided a reliable experimental research platform for the LPI process driven by broadband lasers. Aiming at the strong stimulated Brillouin scattering (SBS) and stimulated Raman scattering (SRS) in the LPI process of large-scale low-density plasma, forward scattering experiment and near-forward scattering experiment on C<sub>8</sub>H<sub>8</sub> planar film targets driven by broadband laser and narrowband laser under the same conditions are carried out. Based on the “Kunwu” laser facility, two sets of measurement systems are designed, one is centered around fiber-heads and spectrometer, and the other around phototubes and oscilloscope. These systems enable multi-directional precise measurements of scattered lightand a comprehensive analysis of LPI. The main focus is on the comparison of the components and spectral information of the scattering beams between broadband laser and narrowband laser, and it is found that the LPI processes driven by broadband laser and narrowband laser are greatly different. Additionally, preliminary results indicate that broadband laser exhibits a stronger penetration capability than narrowband laser. The time to ablation the target and penetrate the plasma are both nearly 1 ns ahead, with the transmitted energy increased by nearly an order of magnitude. And after penetrating the plasma, there is a smaller spatial divergence angle. These results provide good reference value for better understanding the effect of broadband laser on LPI.

A dataset of dryland ground temperature in typical small watersheds in the hilly areas of Central Sichuan Basin (1997-2021)

The underlying surface temperature (i.e. land surface temperature) and soil temperature at different depths are collectively referred to as ground temperature. The variations and variation rules of ground temperature comprehensively depict the exchange of energy and materials between the atmosphere and the land surface. Hence ground temperature is an important parameter for assessing soil thermal conditions. Located in the agro-ecological zone of subtropical Sichuan Basin, Sichuan Yanting Agro-ecosystem Research Station in Chinese National Ecosystem Research Network (also referred to as Yanting Station, code YGA) serves as an experimental observation and research platform of Agro-Ecosystem set by the Chinese Ecosystem Research Network (CERN) and the National Science and Technology Infrastructure Platform in this ecological region. This dataset is based on the long-term automatic station observation data and manual observation data of the comprehensive meteorological observation field of Yanting Station. It consists of four data files, namely, hourly ground temperature data from the automatic observation stations on a daily basis (1997-2021), daily ground temperature statistical data from the automatic observation stations (2004-2021), monthly statistical data of ground temperature from the automatic observation stations (2004-2021) and daily and monthly surface temperature data form the manual observation stations (2004-2021). The data volume is about 8.85 MB. Ground temperature is the networked observation index of field stations. Observation instruments, data acquisition procedures, and data quality control adhere to standardized norms and protocols, ensuring the utmost reliability and comparability of ground temperature data. The accumulation of long time series and multi-level geothermal data can provide scientific data support for the energy and material exchange of ecosystem, the response to environmental change, and the application research of cultivated land quality assessment and food security in the main agricultural areas of the basin.

A fully automated normothermic machine perfusion system for kidney grafts supporting physiological motivated flow profiles

Abstract Research showed that the normothermic machine perfusion of kidneys can enable prolonged storage and improve conditions compared to traditional cold storage. For research in this area, there is a demand for a long-term in vitro perfusion setup. In this work, we present a fully automated normothermic machine perfusion (NMP) system as an experimental research platform. The perfusion system is intended as a tool for researching the effects of different perfusion strategies on the kidney. To enable the automation, the NMP system consists of a blood pressure control, a circulation volume level control and a pH-regulation component. The setup is realized as a medical cyber-physical system consisting of networked embedded microcontroller nodes.

Terracotta: A tool for conducting experimental research on student learning.

For researchers seeking to improve education, a common goal is to identify teaching practices that have causal benefits in classroom settings. To test whether an instructional practice exerts a causal influence on an outcome measure, the most straightforward and compelling method is to conduct an experiment. While experimentation is common in laboratory studies of learning, experimentation is increasingly rare in classroom settings, and to date, researchers have argued it is prohibitively expensive and difficult to conduct experiments on education in situ. To address this challenge, we present Terracotta (Tool for Education Research with RAndomized COnTrolled TriAls), an open-source web application that integrates with a learning management system to provide a comprehensive experimental research platform within an online class site. Terracotta automates randomization, informed consent, experimental manipulation of different versions of learning activities, and export of de-identified research data. Here we describe these features, and the results of a live classroom demonstration study using Terracotta, a preregistered replication of McDaniel et al. (Journal of Applied Research in Memory and Cognition, 1(1), 18-26,2012). Using Terracotta, we experimentally manipulated online review assignments so that consenting students alternated, on a weekly basis, between taking multiple-choice quizzes (retrieval practice) and reading answers to these quizzes (restudy). Students' performance on subsequent exams was significantly improved for items that had been in retrieval practice review assignments. This successful replication demonstrates that Terracotta can be used to experimentally manipulate consequential aspects of students' experiences in education settings.

Exploring the Influencing Factors of Cooperative Behavior Based on Social Value Orientation and Reward Approach Perspective

This study deploys a public goods game experiment using oTree's online behavioural experimental research platform to investigate the effects of introducing different types of rewards on the cooperative behaviour of two types of groups. There are four types of experimental categories. In the public goods game experiment, subjects were first required to perform a triple response matrix to determine the social attributes of individuals, and then to conduct four different types of investment decision experiments in turn. The results of the experiment showed that subjects with different social attributes showed different investment decision behaviours in teamwork, and different types of rewards also influenced the subjects' performance in cooperative behaviour, but the interaction between individual social attributes and reward types did not find significant evidence of an effect on cooperative behaviour at present. After further regression analysis, the present study found that material rewards had a more significant effect on changing subjects' behaviour than mental rewards and that both continuous and fixed interval material rewards had a significant positive effect on subjects' cooperative behaviour. The results in this study suggest different reward methods and the response of team members to the reward methods, and how to establish a positive link between reward incentives and cooperation to facilitate the achievement of cooperative goals.

Reaction-Diffusion Modeling of E. coli Colony Growth Based on Nutrient Distribution and Agar Dehydration.

The bacterial colony is a powerful experimental platform for broad biological research, and reaction-diffusion models are widely used to study the mechanisms of its formation process. However, there are still some crucial factors that drastically affect the colony growth but are not considered in the current models, such as the non-homogeneously distributed nutrient within the colony and the substantially decreasing expansion rate caused by agar dehydration. In our study, we propose two plausible reaction-diffusion models (the VN and MVN models) based on the above two factors and validate them against experimental data. Both models provide a plausible description of the non-homogeneously distributed nutrient within the colony and outperform the classical Fisher-Kolmogorov equation and its variation in better describing experimental data. Moreover, by accounting for agar dehydration, the MVN model captures how a colony's expansion slows down and the change of a colony's height profile over time. Furthermore, we demonstrate the existence of a traveling wave solution for the VN model.

Development of an Instantaneous Loading Impact Test System for Containment of a Nuclear Power Plant during Aircraft Impact on Steel Bar Joints.

As major projects such as nuclear power plants continuously increase, it is inevitable that loopholes will arise in safety precautions. Airplane anchoring structures, comprising steel joints and acting as a key component of such a major project, directly affect the safety of the project due to their resistance to the instant impact of an airplane. Existing impact testing machines have the limitations of being unable to balance impact velocity and impact force, as well as having inadequate control of impact velocity; they cannot meet the requirements of impact testing for steel mechanical connections in nuclear power plants. This paper discusses the hydraulic-based principle of the impact test system, adopts the hydraulic control mode, and uses the accumulator as the power source to develop an instant loading test system suitable for the entire series of steel joints and small-scale cable impact tests. The system is equipped with a 2000 kN static-pressure-supported high-speed servo linear actuator, a 2 × 22 kW oil pump motor group, a 2.2 kW high-pressure oil pump motor group, and a 9000 L/min nitrogen-charging accumulator group, which can test the impact of large-tonnage instant tensile loading. The maximum impact force of the system is 2000 kN, and the maximum impact rate is 1.5 m/s. Through the impact testing of mechanical connecting components using the developed impact test system, it was found that the strain rate of the specimen before failure was not less than 1 s-1, meeting the requirements of the technical specifications for nuclear power plants. By adjusting the working pressure of the accumulator group, the impact rate could be controlled effectively, thus providing a strong experimental platform for research in the field of engineering for preventing emergencies.

Beyond mobile phone displays: Flat panel display technology for biomedical applications

Organ-on-Chips (OoCs) have emerged as a human-specific experimental platform for preclinical research and therapeutics testing that will reduce the cost of pre-clinical drug development, provide better physiological relevance and replace animal testing. Yet, the lack of standardization and cost-effective fabrication technologies can hamper wide-spread adoption of OoCs. In this work we validate the use of flat panel display (FPD) technology as an enabling and cost-effective technology platform for biomedical applications by demonstrating facile integration of key OoC modules like microfluidics and micro electrode arrays (MEAs) in the standardized 96-well plate format. Individual and integrated modules were tested for their biological applicability in OoCs. For microelectrode arrays we demonstrate 90–95% confluency, 3 days after cell seeding and >70% of the initial mitochondrial cell activity for microfluidic devices. Thus highlighting the biocompatibility of these modules fabricated using FPD technology. Furthermore, we provide two examples of monolithically integrated microfluidics and microelectronics, i.e. integrated electronic valves and integrated MEAs, that showcase the strength of FPD technology applied to biomedical device fabrication. Finally, the merits and opportunities provided by FPD technology are discussed through examples of advanced structures and functionalities that are unique to this enabling platform.

Data optimization for the knowledge bases in the oil and gas Monitoring-While-Drilling (MWD) Systems

The ability of a knowledge-oriented system to learn requires the selection and organization of data. The article is devoted to the disclosure of the stages of data preparation for the application of case-based procedures to support decision-making by the operator of the technological process in the field of oil and gas wells drilling. The presented concept allows concentrating expert experience in the subject area and satisfies the criteria of the main sources of knowledge required for the functioning of case-based considerations. The main potential of artificial intelligence to learn is based on semantic dictionaries of the subject area, case databases in the form of knowledge bases, metrics of similarity, adaptation and configuration containers, which are identified as the sources of knowledge. The effectiveness of using computer simulators as a platform for experimental research of new models of complex technological processes is estimated.

Robotic Park: Multi-Agent Platform for Teaching Control and Robotics

Multi-agent system research is a hot topic in different application domains. In robotics, multi-agent robot systems (MRS) can realize complex tasks even if the behavior of each individual agent seems simple thanks to the cooperation between them. Although many control algorithms for MRS are proposed, few experimental results are validated on real data, being essential to building new testbeds to conduct MRS research and teaching. Moreover, most existing platforms for experimentation do not offer an overall solution allowing software and hardware design tools. This paper describes the design and operation of Robotic Park, a new indoor experimental platform for research in multi-agent systems. The heterogeneity and flexibility of its configuration are two of its main features. It supports control strategies design and validation of MRS algorithms. Experiences can be carried out in a virtual environment, in a physical environment, or under a hybrid scheme, as digital twins have been developed in Gazebo and Webots. Currently, two types of aerial vehicles, the Crazyflie 2.X and the DJI Tello, are available. It also includes two types of differential mobile robots, the Turtlebot3 and the Khepera IV. Both internal and external positioning systems using different technologies such as Motion Capture or Ultra-WideBand are also available for experiences. All components are connected through ROS2 (Robot Operating System 2) which enables experiences under a centralized, distributed, or hybrid scheme, and different communication strategies can be implemented. A mixed reality experience that addresses the problem of formation control using event-based control illustrates the platform usage.

Active Stirling Thermocompressor: Modelling and effects of controlled displacer motion profile on work output

Recent work suggests that Stirling device performance can be improved using a decoupled, actively controlled displacer piston to directly shape the device’s thermodynamic behavior. In this paper, the authors validate the controlled displacer concept using a low-frequency thermocompressor platform whose displacer and power output mechanisms are not kinematically coupled. As a little-known class of Stirling devices whose work output is pneumatic rather than mechanical, the thermocompressor presents new challenges for modeling and experimental validation because few devices have actually been built and tested. The device presented here is currently the highest pressure experimental research platform of a Stirling thermocompressor known to the authors. A third-order dynamic model is derived using first principles and is validated against experimental results. The model contains parameters that are known and/or measurable and as such is not a “fitted” model. This first-principles model is used to explore the influence of different displacer motion profiles on the output of the thermocompressor. The model is able to incorporate an arbitrarily-specifiable displacer motion profile. Using a controlled displacer piston profile, we experimentally demonstrate 1.45X higher peak cycle power and 3.6X higher work output, compared to a traditional sinusoidal displacer motion. This model is appropriate for optimizing the control of the displacer motion with respect to desired thermocompressor power, efficiency, or other performance metrics for any general Stirling thermocompressor.

Effects of aspect ratio and inlet wind velocity on thermal characteristics of Trombe wall channel under different ventilation strategies: An indoor experiment

Due to the air flow channel's “C”-shaped structure with asymmetric thermal boundary conditions, the structural and operating parameters have unique intrinsic impacts on overall performance of Trombe wall. In order to match the engineering practice well, under laboratory conditions, an experimental research platform with adjustable channel width and fans was established to reveal the effects of aspect ratio and inlet wind velocity on thermal characteristics of air flow channel under different ventilation strategies. The results show that under natural ventilation strategy, the air flow channel's thermal performance has an extremum when the aspect ratio is about 0.05. Under forced ventilation strategy, with the growth of inlet wind velocity, the comprehensive average convective heat transfer coefficient rises while thermal efficiency shows different trends under various heat fluxes and reaches the maximum when heat flux is greater than 360 W/m2 and inlet wind velocity is 0.6 m/s. A larger aspect ratio leads to a lower comprehensive convective heat transfer coefficient and a smaller thermal efficiency. Compared with the natural ventilation strategy, except for the air temperature rise, the air flow channel's thermal performance is improved to a certain extent under forced ventilation strategy. The improvement of thermal efficiency is particularly significant when the heat flux is small, indicating that forced ventilation strategy has high application potential in areas with low solar radiation intensity. Finally, the Nusselt number correlations reflecting comprehensive average convective heat transfer performance of Trombe wall channel under two ventilation strategies were obtained for engineering design and performance evaluation of Trombe wall.

Ultrafast visualization of an electric field under the Lorentz transformation

In special relativity, four-vectors, such as space–time, energy–momentum and electromagnetic potential vectors, follow the Lorentz transformation. The transformations of space–time and energy–momentum vectors have been tested by time dilation and rest mass energy experiments, respectively. However, the Lorentz transformation of electromagnetic potentials has never been directly demonstrated in experiments due to the limitations of the diagnostics. Here we show the spatiotemporal electric-field profiles around a highly energetic electron beam with a subpicosecond temporal resolution obtained by a terahertz technique based on electro-optic sampling. We observe the Coulomb field contraction in the propagation direction of the beam under the Lorentz transformation. After passing the beam through a metallic plate, we investigate the birth of the Coulomb field around it and follow the spatiotemporal evolution of the spherical wavefront, which is derived by the Liénard–Wiechert potentials. The measured electric-field profile in the far propagation distance is experimentally confirmed to coincide with the calculation of the Liénard–Wiechert potentials and the Lorentz transformation. Our ultrafast measurement of a spatiotemporal relativistic electric field provides both additional experimental evidence of special relativity and a platform for detailed experimental research of energetic charged particle beams and electromagnetic radiation physics.

Towards Integrated Digital-Twins: An Application Framework for Autonomous Maritime Surface Vessel Development

The use of digital twins for the development of Autonomous Maritime Surface Vessels (AMSVs) has enormous potential to resolve the increasing need for water-based navigation and safety at the sea. Aiming at the problem of lack of broad and integrated digital twin implementations with live data along with the absence of a digital twin-driven framework for AMSV design and development, an application framework for the development of a fully autonomous vessel using an integrated digital twin in a 3D simulation environment has been presented. Our framework has 4 layers which ensure that simulation and real-world vessel and the environment are as close as possible. Åboat, an in-house, experimental research platform for maritime automation and autonomous surface vessel applications, equipped with two trolling electric motors, cameras, LiDARs, IMU and GPS has been used as the case study to provide a proof of concept. Åboat, its sensors, and the environment have been replicated in a commercial, 3D simulation environment, AILiveSim. Using the proposed application framework, we develop obstacle detection and path planning systems based on machine learning which leverage live data from a 3D simulation environment to mirror the complex dynamics of the real world. Exploiting the proposed application framework, the rewards across training episodes of a Deep Reinforcement Learning model are evaluated for live simulated data in AILiveSim.

Development and Initial Experimental Results of a Terahertz Pulsed Field Gyrotron in the WHMFC

We report the design and initial experimental results of an 800-GHz second harmonic gyrotron prototype, in which a 15-T pulsed magnet is applied. This gyrotron prototype is developed at the Wuhan National High Magnetic Field Center (WHMFC). An in-house software for analyzing and designing terahertz gyrotrons and an experimental research platform are developed. In addition, alignment adjustments, eddy current effects, and radiation tests are discussed. The initial experimental results show that the prototype gyrotron can irradiate ~40 W at fundamental harmonic 383.7-GHz (TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1,4</sub> ) waves at 14.14 T and a few milliwatts at second harmonic 0.8-THz (TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8,5</sub> ) waves at 14.86 T.