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Bacteria and their derivatives (membrane vesicles, MVs) exhibit great advantages for targeting hypoxic tumor cores, strong penetration ability and activating immune responses, holding great potential as auspicious candidates for therapeutic and drug-delivery applications. However, the safety issues and low therapeutic efficiency by single administration still need to be solved. To further optimize their performance and to utilize their natural abilities, scientists have strived to modify bacteria with new moieties on their surface while preserving their advantages. The aim of this review is to give a comprehensive overview of a non-genetic engineering modification strategy that can be used to optimize the bacteria with nanomaterials and the design strategy that can be used to optimize MVs for better targeted therapy. Here, the advantages and disadvantages of these processes and their applicability for the development of bacteria-related delivery system as antitumor therapeutic agents are discussed. The prospect and the challenges of the above targeted delivery system are also proposed.

Background During the epidemic, the mental health of college students was generally poor, especially anxiety and depression, which should be treated using counseling and intervention. This study aimed to observe the influence of dialectical behavior therapy on the anxiety and depression of medical students during the normalization of the prevention and control of the COVID-19 epidemic. Methods A total of 26 medical students (experimental group) were treated with dialectical behavior therapy intervention for 4 weeks. Changes in depression, anxiety, and stress levels were assessed by the Patient Health Questionnaire (PHQ-9), the Generalized Anxiety Disorder (GAD-7) scale, the Somatic Self-rating Scale (SSS), and the Perceived Stress Scale (PSS-10). This group was compared with 26 medical students (control group) without intervention. Results The value-added scores of the PHQ-9 (t=2.543, P=0.014) and GAD-7 scales (t=3.790, P=0.000) in the experimental group were significantly higher than those in the control group, while in the SSS scale, the value-added score of the depressive symptoms subscale (t=2.234, P=0.030) in the experimental group was significantly higher than that of the control group. For the total score of the PSS-10 scale (t=2.435, P=0.018), the value-added score of the experimental group was significantly higher than that of the control group. Conclusions The intervention of dialectical behavior therapy can effectively alleviate the depression and anxiety of medical students during the normalization of epidemic prevention and control. Trial registration Chinese Clinical Trial Registry ChiCTR2100048784.

As a promising ion source, the radio frequency (RF)–driven ion source is widely equipped in the neutral beam injector of magnetic-confinement fusion devices. In order to study the characteristics o...

Nuclear fusion is one of the most effective methods to solve future energy problems. In this field, Tokamak is a machine that confines a plasma using magnetism, and the way of neutral beam injection (NBI) is considered one of the most effective auxiliary heating methods for it. The necessary numerical simulation of the NBI system will provide scientific data guidance for the safe and effective operation of the experiment. More importantly, the high-energy particles produced by the neutral beam injector could cause severe damage to the Tokamak device and injector itself. Based on the above requirements, the transmission characteristics of the neutral beam are analyzed, and a calculation mode of the beam intensity is studied in this paper. Moreover, the energy deposition of the beam power is simulated by the C++ program platform, and the beam intensity is visualized. After testing, the stability of the program is demonstrated, and the data obtained from the experiment provide the necessary support for setting the parameters in the neutral beam injector. Meanwhile, the simulations of power deposition at different locations provide indispensable references for subsequent improvements in the design of the neutral beam injector.

For the equipment protection of NBI injection process, a remote way of infra-red temperature measuring system was proposed for the monitoring of beam injection target tiles of EAST inner wall. Considering that, it’s non-intrusive and quick response, electric circuits and parts are distant away from the tokmak reaction thus immunized from radiation affection.

Neutral Beam Injection (NBI) is one of the four efficient ways of assistant heating on the Experimental Advanced Superconducting Tokamak (EAST) device. Measures have been taken to ensure more reliable monitoring of NBI components’ thermal data. Infrared thermometers, unlike surface-mounted thermocouples, have the advantage of non-contact and thus will not cause interference and get far less chance of malfunctioning [Childs et al., Rev Sci. Instruments 71, 2959–2978 (2000)]. In this paper, the remote infrared temperature measurement with optical fiber is reported to meet the requirement of the EAST-NBI diagnostic system. Some tests have been conducted on the remote infrared temperature measurement under the working condition, and an atmospheric propagation simulation was performed to estimate the atmosphere absorption. The results indicate that the detector’s response is in line with the theory, and the atmosphere absorption within a certain wavelength should not be ignored. Temperature measurement error is within one percent at temperatures above 200 °C. So, for the temperature range of 200–600 °C, the remote infrared temperature measurement by the optical fiber can fully meet its expectation.

Mentorship in science is crucial for topic choice, career decisions, and the success of mentees and mentors. Typically, researchers who study mentorship use article co-authorship and doctoral dissertation datasets. However, available datasets of this type focus on narrow selections of fields and miss out on early career and non-publication-related interactions. Here, we describe Mentorship, a crowdsourced dataset of 743176 mentorship relationships among 738989 scientists primarily in biosciences that avoids these shortcomings. Our dataset enriches the Academic Family Tree project by adding publication data from the Microsoft Academic Graph and “semantic” representations of research using deep learning content analysis. Because gender and race have become critical dimensions when analyzing mentorship and disparities in science, we also provide estimations of these factors. We perform extensive validations of the profile–publication matching, semantic content, and demographic inferences, which mostly cover neuroscience and biomedical sciences. We anticipate this dataset will spur the study of mentorship in science and deepen our understanding of its role in scientists’ career outcomes.

Even though computer science (CS) has had a historical lack of gender and race representation, its AI research affects everybody eventually. Being partially rooted in CS conferences, “AI ethics” (AIE) conferences such as FAccT and AIES have quickly become distinct venues where AI’s societal implications are discussed and solutions proposed. However, it is largely unknown if these conferences improve upon the historical representational issues of traditional CS venues. In this work, we explore AIE conferences’ evolution and compare them across demographic characteristics, publication content, and citation patterns. We find that AIE conferences have increased their internal topical diversity and impact on other CS conferences. Importantly, AIE conferences are highly differentiable, covering topics not represented in other venues. However, and perhaps contrary to the field's aspirations, white authors are more common while seniority and black researchers are represented similarly to CS venues. Our results suggest that AIE conferences could increase efforts to attract more diverse authors, especially considering their sizable roots in CS.

The neutral beam injection(NBI) is one of the most effective heating and current driven methods. The ion source is the important part of beam line, which electric parameters are important for experimental operation and troubleshooting. In order to acquiring the experimental parameters of ion source, the data acquisition system of electric parameters of ion source for NBI has been developed. Considering the galvanic isolation, the data acquisition system must contain the function of isolation transmission. The transmission rate of the system reaches 3kHz, which meets the experimental demands absolutely. Experimental results show that the data acquisition system achieves the measurement of current and voltage signals of ion source.

Neutral beam injection(NBI) is one of the most effective heating methods in fusion experiments. In the duration of injection, the unabsorbed energetic neutral particles will penetrate plasma and shot at the armor tiles, which are located at in the opposite of injection windows. The temperature of armor tiles will be increased by the shooting of unabsorbed energetic neutral particles. If the temperature rising of armor tiles is above the maximum safety temperature, they will be damaged or displaced by the thermal load. In order to ensure the process of physical experiments and the safety of armor tiles, the monitoring system of infrared thermometer has been developed. The functions of remote isolation transmission, real time monitoring, local displaying and fast protection are embed in the monitoring system.

In order to study the generation and extraction of negative ions for neutral beam injection application, a prototype radio frequency driven negative ion source and the corresponding test bench are under construction at the Institute of Plasma Physics, Chinese Academy of Sciences. A new design of infrared radiation diagnostic calorimeter for testing beam characteristics is put forward. Compared with the conventional calorimeter, the calorimeter adopts the block structure (8 × 28 tungsten hexahedron blocks) and modularization design (4 modules), so it has higher precision and good scalability. The thermal performance of the calorimeter is assessed using a finite element method. Simulation results show that the design can be achieved to operate in the stable-state mode at the maximum thermal flux 6.45 MW/m2 and meet the full requirement of beam diagnosis.

Detecting biases in artificial intelligence has become difficult because of the impenetrable nature of deep learning. The central difficulty is in relating unobservable phenomena deep inside models with observable, outside quantities that we can measure from inputs and outputs. For example, can we detect gendered perceptions of occupations (e.g., female librarian, male electrician) using questions to and answers from a word embedding-based system? Current techniques for detecting biases are often customized for a task, dataset, or method, affecting their generalization. In this work, we draw from Psychophysics in Experimental Psychology---meant to relate quantities from the real world (i.e., "Physics") into subjective measures in the mind (i.e., "Psyche")---to propose an intellectually coherent and generalizable framework to detect biases in AI. Specifically, we adapt the two-alternative forced choice task (2AFC) to estimate potential biases and the strength of those biases in black-box models. We successfully reproduce previously-known biased perceptions in word embeddings and sentiment analysis predictions. We discuss how concepts in experimental psychology can be naturally applied to understanding artificial mental phenomena, and how psychophysics can form a useful methodological foundation to study fairness in AI., Comment: FAT Conference 2020

According to the latest physics design of the China Fusion Engineering Test Reactor (CFETR), two neutral beam injectors (NBIs), which deliver a total of 40 MW in not less than 3600 s with 1 MeV D0, are demanded to support current drive and plasma rotation. To minimize the risks and time to provide the CFETR with reliable NBIs, a negative NBI test facility will be developed at the Institute of Plasma Physics, Chinese Academy of Science. Its mission is to understand the characteristics of the RF driven ion source and negative ion generation and extraction and to improve RF efficiency and beam quality. In order to achieve this goal, a set of diagnostic tools will be used in this test facility. For source diagnostics, optical emission spectroscopy, cavity ring-down spectroscopy, laser absorption spectroscopy, and electrostatic probes are planned to be used. Beam emission spectroscopy, W-wire calorimeters, 1D carbon fiber composite diagnostic calorimeters, beam dump with thermocouples, and water-flow calorimetry are used to assess the beam properties. The design of the diagnostic system is presented.

Neutral beam injection is recognized as one of the most effective methods for plasma heating. According to the requirements for physics experiments of the Experimental Advanced Superconducting Tokamak (EAST), two beamlines for neutral beam injection were built in 2014. In order to meet the diverse requirements of magnetic confinement experiments, recent attempts have been carried out for arc power control of a neutral beam injection ion source. A test system was added to the arc power control system. It provides a new method to smoothly change arc power during a discharge. According to the experimental results of controlling arc power, the fesibility of varying the arc power was verified in the duration of discharge. Meanwhile, the test system achieves the remote setting of arc power parameters.

Purpose To investigate the protective effects of miR-320 on cerebral ischemia/reperfusion (I/R) injury in mice and PC12 cells. Methods miR-320 normal control (NC), inhibitor fragment and overexpression fragments were injected into mice lateral ventricles. Thereafter, the middle cerebral artery occlusion (MCAO) for left cerebrum method was employed in order to establish a cerebral I/R injury mice model. Apoptosis in the peripheral region of cerebral infarction and the volume of cerebral infarction and brain edema were tested as well. For simulating MCAO in vitro, the PC12 cells were subjected to oxygen-glucose deprivation. The lentivirus transfection technique was used to overexpress or inhibit miR-320. Furthermore, the effects of miR-320 on the survival and apoptosis of PC12 were monitored by MTT and TUNEL detection. Results A cerebral I/R injury mice model was successfully established. MiR-320 enhanced cell apoptosis of the injury side cortical infarcted peripheral zone and increased brain infarction volume and edema volume in MCAO/R mice. In addition, Insulin growth factor-1 (IGF-1) mRNA and protein expressions in MCAO/R mice were inhibited by miR-320 as well. Moreover, the results of cell studies were consist with the animal studies. Conclusions miR-320 may be involved in the regulation of cerebral I/R for brain parenchyma injury by inhibition of IGF-1 pathway.

The extraction grid power supply (EGPS) is important for neutral beam injection of tokamak, which is used to extract the negative ions from the plasma source. A set of power supply with pulse step modulation topology at 16 kV/20 A has been designed for the negative ions extraction at the Institute of Plasma Physics, Chinese Academy of Sciences, which meets the requirements of fast dynamics, low ripple, and good output operation. The development of EGPS is presented in this paper. Two different voltage ratings and series-connected switched power supply (SPS) modules are fed from multisecondary transformer. Insulated-gate bipolar transistors are applied to the switch of SPS module. Rise time and fall time of EGPS out voltage can be set from few microseconds to milliseconds. When the overcurrent occur, the output voltage falls to zero less than $5~\mu \text{s}$ . The dynamic performance tests with dummy load of EGPS are presented. The testing results indicate that the power supply meets the demands of negative ions extraction. The design provides a foundation for the next phase of extraction experimental operation for radio frequency ion source.

An RF-driven negative-ion source development program has been started at ASIPP-Hefei with a small test equipment, Hefei utility negative ion test equipment with RF source (HUNTER). It is devoted to some crucial issues of the RF-driven negative-ion source, such as the improvement of RF efficiency, the enhancement of the extracted negative-ion current density, and the promotion of the beam qualities. In the initial stage, the HUNTER negative-ion source conservatively adopted a similar structure of the ITER prototype source developed at IPP, Garching. It consists of single or double RF driver on the back side of a plasma expansion chamber, and a negative ion accelerator which is able to extract 120 beamlets up to 60 kV for 10 s. In the first phase operation of the HUNTER-ion source, a low-pressure (0.3 Pa) plasma has been successfully achieved by coupling 46-kW RF input power and different plasma parameters have been measured by using Langmuir probes and optical emission spectroscopy. Besides the negative-ion source, the HUNTER comprises the vacuum vessel, the special cooling system, the power supply system, and the source plasma and beam diagnostic system are also ready for the next phase operation of hydrogen negative ion beam extraction.

The ion source is the critical part of Experimental Advanced Superconducting Tokamak (EAST) neutral beam injection (NBI) system. Two ion sources are equipped in one beam line. The voltage and current signals of grids are the important diagnostic data in the duration of beam extraction, especially the rising and sparking edge. In order to achieve the functions of data acquisition and isolation transmission, the first prototype of high-speed data acquisition system of ion source has been developed. The system contains the advantages of 40 MS/s sampling rate, 8-bits resolution and optical isolation transmission. Field programmable gate array (FPGA) is used as the control chip in the system. The system has been tested for the voltage of plasma grid (PG) and the beam current. The error range of system is

An important feature of the China Fusion Engineering Test Reactor (CFETR) project is the additional heating obtained from the injection of neutral beams based on accelerated negative ions. For the neutral beams based on negative ions, the most important measurements are beam uniformity, beamlet divergence, and stripping losses. According to the CFETR requirement, the maximum allowed beam divergence angle and beam nonuniformity are 6 mrads and ±10%, respectively. As one-dimensional (1-D) carbon tiles have large ratio between perpendicular conductivity and parallel conductivity and high stability, they can be used for beam uniformity and beamlet divergence measurement. This paper investigates the influence on the response of 1-D carbon tile having the thermal characteristics and features of some dedicated diagnostics. Simulations show that it will be possible to verify experimentally whether the beam meets the requirement about the maximum allowed value. This work lays a foundation for design and ap...

A large area radio frequency (RF) ion source was developed for neutral beam injector in Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). An experiment of RF source was installed in the test facility. The dimension of large area RF source is 862 mm (L) × 472 mm (W) × 420 mm (D). Six turns of coil is used to transfer RF power to the plasma. The plasma density was measured by the movable Langmuir probe in front of the plasma grid. The electron density of 6 × 1017 m−3 was achieved with RF power of 30 kW and source pressure of 0.5 Pa. The density uniformity was estimated as 95%. The heat loading on the Faraday shield and coil were also measured and acceptable for the long pulse operation with high power in the future. The details of the first tests of large area RF plasma source are presented in this paper.

Neutral beam injection heating with negative ion source is one of the important auxiliary heating system to achieve the high parameter steady- state operation goal for CFETR. A Negative ion-based Neutral Beam Verification Facility (NNBVF), a conceptual design for testing the engineering feasibility of neutral beam injection systems, is proposed for the Chinese Fusion Engineering Test Reactor (CFETR). The neutral-beam injectors used for CFETR will operate with deuterium. Inevitably, a large number of neutrons are generated between beam deuterons and deuterons implanted in the calorimeter. Neutron source is one of the important input data for radiation analysis. The neutron characterization on the calorimeter surface were explored by using a multiaperture Gaussian divergence model and the local mixing model. The total neutron intensity reach up to 1.2 × 1014 n/s for 400 keV deuteron beam. Initial results revealed that the aspect ratio of the neutron beam profile decreases with increasing beam divergence. The shape of the neutron profile on the calorimeter surface remains the same for the beam density distributions. This implies the neutron intensity emitted from the target is suitable for the beam density distribution diagnostic applications.

A high-power radio frequency (RF) beam source is a key component for Negative Neutral Beam Injector (NNBI) in ASIPP. According to the technical route planning of CRAFT-NNBI beam source project, ASIPP started the development of quarter-size RF negative source and corresponding test facility. The inner diameter of the faraday shield (FS) of RF driver is 240 mm, the outer diameter of the accelerator is 1 m, with three-layer grids extraction system, which comprises the plasma grid (PG), extraction grid (EG) and ground grid (GG). The size of PG is 512 mm × 396 mm × 9 mm, with two rows of 16 × 6 apertures made of pure molybdenum. The structure design of RF negative beam source and the manufacturing process of key components are presented, with emphasis on the manufacturing process of FS as well as grids. Furthermore, the fluid-thermal-structural analysis of PG, the mechanical analysis and material bonding strength test of the main insulation structure of beam source, as well as the preliminary layout of the latest test facility are presented.

The Comprehensive Research Facility for Fusion Technology (CRAFT) is a large scientific device that is preferentially deployed in China's "Thirteenth Five-Year Plan" for the construction of major national science and technology infrastructures. A beam source of negative neutral beam injector (NNBI) is required for the CRAFT device with the beam energy of 400 keV, neutral beam power of 2 MW, and beam duration of 100 s. The beam source is the key component of NNBI system. A radio frequency (RF) based negative beam source was designed for the CRAFT NNBI system. It contains a large plasma generator and a negative ion accelerator. The plasma generator contains a large expansion chamber and four RF drivers which arrange in a vertical column (1 × 4). The accelerator has a similar design to ITER. Consider the 400 keV beam energy, the accelerator was designed with four layers of electrodes, which are plasma grid, extraction grid, acceleration grid, and ground grid. The detailed structures of negative beam source were designed initially with the RF plasma generator and the negative ion accelerator.

A code to study beam power deposition on the internal components of the DIII-D and EAST neutral beamlines has been developed. The predictions that the code makes are found to be in good agreement with water flow calorimetry measurements for all components except the magnet region. The code is used to predict the power loading on new components being designed for a major beamline upgrade. The shortcomings of the code’s treatment of the magnet region are addressed by utilizing a particle trajectory tracing code and invoking the hypothesis that incomplete space charge neutralization is responsible for the discrepancy.

A prototype negative ion source is in development toward the giant negative ion source for the China Fusion Engineering Test Reactor neutral beam injection system at the Institute of Plasma...