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CD3-engaging bispecific antibodies (BsAbs) have emerged as powerful therapeutic approaches by their ability to redirect T cells to eliminate tumor cells in a major histocompatibility complex–independent manner. However, how we can potentiate the efficacy of BsAbs remains largely unknown. To address this question, we investigated immunological mechanisms of action of a BsAb cotargeting CD3 and B-cell maturation antigen (BCMA) in syngeneic preclinical myeloma models. Treatment with the CD3/BCMA BsAb stimulated multiple CD3-expressing T-cell subsets and natural killer (NK) cells in the myeloma bone marrow (BM), highlighting its broad immunostimulatory effect. Notably, the BsAb-mediated immunostimulatory and antitumor effects were abrogated in mice lacking invariant NKT (iNKT) cells. Mechanistically, activation of iNKT cells and interleukin-12 production from dendritic cells (DCs) were crucial upstream events for triggering effective antitumor immunity by the BsAb. Myeloma progression was associated with a reduced number of BM iNKT cells. Importantly, the therapeutic efficacy of a single dose of CD3/BCMA BsAb was remarkably augmented by restoring iNKT cell activity, using adoptive transfer of α-galactosylceramide-loaded DCs. Together, these results reveal iNKT cells as critical players in the antitumor activity of CD3 engaging BsAbs and have important translational implications.

Due to the discrete nature of the saddle coils for the active feedback control of the plasma instabilities, the emergence of the sideband modes is inevitable. In the Keda Torus eXperiment (KTX), the edge Mirnov coils are unevenly distributed on the inner surface of the vacuum vessel to suppress the sideband modes. These arrays of the Mirnov coils are used for the feedback control system of KTX. They are also used for the magnetohydrodynamics (MHD) mode identification, which is a fundamental and significant method to distinguish and describe the plasma instabilities. A set of suitable MHD mode analysis methods has been utilized to complete the mode detection, including the spatial discrete Fourier transform (SDFT) method, the singular value decomposition (SVD) method and the Lomb periodogram method. These methods can obtain comprehensive mode information of the plasma instabilities and their results can be used as the feedback of the feedback control system. These methods have been successfully applied to detect and characterize an impulsive mode of ( $m = 1$ , $n = 0$ ) and rotating modes of ( $m = 2$ , 3, 4, $n = 1$ ) in the tokamak plasma of KTX, while the matrix decomposition technique is not applicable for KTX.

Solar wind classification is conducive to understand the physical processes ongoing at the Sun and solar wind evolution in the interplanetary space, and furthermore, it is helpful for early warning of space weather events. With rapid developments in the field of artificial intelligence, machine learning approaches are increasingly being used for pattern recognition. In this study, an approach from machine learning perspectives is developed to automatically classify the solar wind at 1 AU into four types: coronal-hole-origin, streamer-belt-origin, sector-reversal-region-origin, and ejecta. By exhaustive enumeration, an eight-dimensional scheme ($B_T$, $N_P$, $T_P$, $V_P$, $N_{\alpha p}$, $T_{exp}/T_P$, $S_p$, and $M_f$) is found to perform the best among 8191 combinations of 13 solar wind parameters. 10 popular supervised machine learning models, namely $k$ Nearest Neighbors (KNN), Support Vector Machines with linear and Radial Basic Function kernels, Decision Tree, Random Forest, Adaptive Boosting, Neural Network, Gaussian Naive Bayes, Quadratic Discriminant Analysis, and Extreme Gradient Boosting, are applied to the labeled solar wind data sets. Among them, KNN classifier obtains the highest overall classification accuracy, 92.8%. It significantly improves the accuracy by 9.6% over existing manual schemes. No solar wind composition measurements are needed, permitting our classification scheme to be applied to most solar wind spacecraft data. Besides, two application examples indicate that solar wind classification is helpful for the risk evaluation of predicted magnetic storms and surface charging of geosynchronous spacecrafts.

Uranus is mainly composed of elements heavier than hydrogen and helium, such as C, S, even though very little information about these elements has been detected. Methane is one of the most important component of the atmosphere of Uranus. Analysis of the full-disk spectra of Uranus, as observed by the Xinglong 2.16m telescope with BFOSC (Beijing-Faint Object Spectrograph and Camera) on August 26 2016, was performed. A simple empirical model was used to fit the several years of spectrum albedo data to determine the variations of the CH4/H2 ratio in the atmosphere of Uranus. These data include: spectra observed by the 1.52m telescope (1994 and 1995) on La Silla, Chile; spectra observed by the HST-STIS (2002 and 2003); and spectra observed by the Xinglong 2.16m telescope (2016). The interannual change of the CH4/H2 ratio can be derived by comparing the fit results of various spectral albedos. The comparative results indicate that the CH4/H2 ratio in the atmosphere of Uranus declined from 1994 until 2002, and then began to rise thereafter. From the results, we speculate that the variation period of CH4/H2 ratio in the atmosphere of Uranus is longer than twenty years. We were unable to confirm whether the period is 84 or 42 years.

The conductive shell in reversed field pinch devices plays an important role in controlling plasma and in suppressing MHD instabilities. The shell in the Keda torus experiment reversed field pinch (KTX-RFP) device includes a 6-mm stainless steel vacuum chamber and a 1.5-mm stabilizing copper shell. This stabilizing shell has both poloidal and toroidal gaps to allow a coupling of electromagnetic energy to the plasma. Nevertheless, any gaps in this shell generate error fields. A 3D electromagnetic field model has been used to study effects of the gap on the shell. Using off-center current filaments instead of the distributed plasma current density, numerical analyses render the induced current distribution on the stabilizing shell and the resultant error field distribution at a specific frequency. From the analyses and comparisons of different configurations for the stabilizing shell, a suitable shell design is chosen consisting of three sections: one primary shell, two poloidal shield shells, and two toroidal shield shells. Moreover, the time evolution of the magnetic field inside and outside the stabilizing shell was obtained for this design and the dependence of the magnetic field penetration time on mode number and location has been investigated.

A poloidal and toroidal magnetic field coupling circuit model is developed to simulate discharge waveforms of the Keda Torus eXperiment (KTX) reversed field pinch (RFP) to ensure that the design of the power supply systems is able to achieve the typical discharge parameters. The radial profiles of plasma current density and magnetic field used in the coupling model are characterized by modified Bessel function model (MBFM) derived from the well-known Taylor's theory. The power balance in the energy conservation of poloidal and toroidal fields is used to establish the connection between these two fields. The numerical solutions of the coupling show that the KTX power supply system is capable of achieving the designed discharge parameters, such as field reversal parameter ( F ), pinch parameter (Θ), magnetic field, plasma current and loop voltage. Furthermore, the delay of magnetic field penetration due to the effect of vacuum vessel is also considered in the model.

Directly tracking an interplanetary coronal mass ejection (ICME) by widely separated spacecrafts is a great challenge. However, such an event could provide us a good opportunity to study the evolution of embedded Alfv\'enic fluctuations (AFs) inside ICME and their contributions to local plasma heating directly. In this study, an ICME observed by Wind at 1.0 au on March 4-6 1998 is tracked to the location of Ulysess at 5.4 au. AFs are commonly found inside the ICME at 1.0 au, with an occurrence rate of 21.7% and at broadband frequencies from 4$\times 10^{-4}$ to 5$\times 10^{-2}$ Hz. When the ICME propagates to 5.4 au, the Aflv\'enicity decreases significantly, and AFs are rare and only found at few localized frequencies with the occurrence rate decreasing to 3.0%. At the same time, the magnetic field intensity at the AF-rich region has an extra magnetic dissipation except ICME expansion effect. The energetics of the ICME at different radial distance is also investigated here. Under similar magnetic field intensity situations at 1.0 au, the turbulence cascade rate at the AF-rich region is much larger than the value at the AF-lack region. Moreover, it can maintain as the decrease of magnetic field intensity if there is lack of AFs. However, when there exists many AFs, it reduces significantly as the AFs disappear. The turbulence cascade dissipation rate within the ICME is inferred to be 1622.3 $J\cdot kg^{-1}\cdot s^{-1}$, which satisfies the requirement of local ICME plasma heating rate, 1653.2 $J\cdot kg^{-1}\cdot s^{-1}$. We suggest that AF dissipation is responsible for extra magnetic dissipation and local plasma heating inside ICME., Comment: 15 pages, 3 figures, 1 table

The Keda Torus eXperiment (KTX) is a new reversed field pinch (RFP) device at the University of Science and Technology of China. The construction and assembly of KTX, including the vacuum chamber, conducting shell, magnetic field windings, power supply system, active control coils, vacuum pump and data acquisition system, have been completed on August 1, 2015. Immediately following that, the first plasma was obtained on August 15, 2015. Intensive conditioning of the machine is underway to ramp up the plasma current toward its full operation. An active feedback mode control system has been built and has been implemented to control the error field around the vertical gaps of the conducting shell. The pulsed power supply systems of ohmic heating field and toroidal field (TF), using thyristor and energy storage capacitors, have been tested and commissioned. The TF power supply has flexibility in being able to operate with a reversed TF configuration and stable TF configuration. The fundamental diagnostic tools are developed for early KTX operation. Currently, the plasma current is up to 205 kA and the maximum discharge length is 21 ms, approaching to the conducting shell penetration time. Furthermore, typical RFP discharges are being produced with RFP state lasting 2 ms. These initial operation results for KTX are described in detail.

In a reversed field pinch device, the conductive shell is placed as close as possible to the plasma so as to balance the plasma during discharge. Plasma instabilities such as the resistive wall mode and certain tearing modes, which restrain the plasma high parameter operation, respond closely with conditions in the wall, in essence the eddy current present. Also, the effect of eddy currents induced by the external coils cannot be ignored when active control is applied to control instabilities. One diagnostic tool, an eddy current probe array, detects the eddy current in the composite shell. Magnetic probes measuring differences between the inner and outer magnetic fields enable estimates of the amplitude and angle of these eddy currents. Along with measurements of currents through the copper bolts connecting the poloidal shield copper shells, we can obtain the eddy currents over the entire shell. Magnetic field and eddy current resolutions approach 2 G and 6 A, respectively. Additionally, the vortex electric field can be obtained by eddy current probes. As the conductivity of the composite shell is high, the eddy current probe array is very sensitive to the electric field and has a resolution of 0.2 mV/cm. In a bench test experiment using a 1/4 vacuum vessel, measurements of the induced eddy currents are compared with simulation results based on a 3D electromagnetic model. The preliminary data of the eddy currents have been detected during discharges in a Keda Torus eXperiment device. The typical value of toroidal and poloidal eddy currents across the magnetic probe coverage rectangular area could reach 3.0 kA and 1.3 kA, respectively.

Studies on Sun-climate connection have been carried out for several decades, and almost all of them focused on the effects of solar total irradiation energy. As the second major terrestrial energy source from outer space, the solar wind energy flux exhibits more significant long-term variations. However, its link to the global climate change is rarely concerned and remains a mystery. As a fundamental and important aspect of the Earth's weather and climate system, tropical cyclone activity has been causing more and more attentions. Here we investigate the possible modulation of the total energy flux input from the solar wind into the Earth's magnetosphere on the global tropical cyclone activity during 1963–2012. From a global perspective, the accumulated cyclone energy increases gradually since 1963 and starts to decrease after 1994. Compare to the previously frequently used parameters, e.g., the sunspot number, the total solar irradiation, the solar F10.7 irradiation, the tropical sea surface temperature, and the south oscillation index, the total solar wind energy flux input exhibits a better correlation with the global tropical cyclone activity. Furthermore, the tropical cyclones seem to be stronger with more intense geomagnetic activities. A plausible modulation mechanism is thus proposed to link the terrestrial weather phenomenon to the seemingly-unrelated solar wind energy input.

The Keda Torus eXperiment (KTX) is still operated in the commissioning phase, and preparation for the operation capability of the KTX phase II upgrade is underway. The diagnostics in the KTX have been greatly developed: (1) the terahertz interferometer has been upgraded to seven chords for electron density profile inversion; (2) a Thomson scattering system with a 5 Joule laser has been installed and commissioning is in progress; (3) a 3D movable probe system has been developed for the electromagnetic turbulence measurement; (4) double-foil soft x-ray imaging diagnostics have been set up and a bench test has been completed; (5) an edge capacitive probe has been installed for the radial electrical field measurement; (6) a multi-channel spectrograph system has been built for detecting impurities of carbon and oxygen. In addition, the design of a new compact torus injection system has been completed for feeding and momentum driving. Pilot research, such as the 3D reversed field pinch physics and electromagnetic turbulence, etc, have been conducted in the discharge status of the KTX. The 3D spectra characters of electromagnetic turbulence are firstly measured using a classical two-point technique by Langmuir probe arrays set on the 3D movable probe system and edge magnetic sensors. The forward scattering is collected by the interferometer system, which shows the potential for turbulence research. The electromagnetic turbulence is tentatively investigated in the KTX. The formation of a quasi-single-helicity state in the KTX regime is also preliminarily explored in simulation.

The design of the poloidal field (PF) system includes the ohmic heating field system and the equilibrium (EQ) field system, and is the basis for the design of a magnetic confinement fusion device. A coupling between the poloidal and plasma currents, especially the eddy current in the stabilizing shell, yields design difficulties. The effects of the eddy current in the stabilizing shell on the poloidal magnetic field also cannot be ignored. A new PF system design is thus proposed. By using a low-μ material (μ = 0.001, e = 1) instead of a conductive shell, an electromagnetic model is established that can provide a continuous eddy current distribution on the conductive shell. In this model, a 3D time-domain problem with shells translates into a 2D magnetostatic problem, and the accuracy of the calculation is improved. Based on these current distributions, we design the PF system and analyze how the EQ coils and conductive shell affect the plasma EQ when the plasma ramps up. To meet the mainframe design requirements and achieve an efficient power-supply design, the position and connection of the poloidal coils are optimized further.

The first imaging observation experiment of the atmospheric gravity waves in the mesopause region with the all-sky OH* Meinel band airglow CCD imager is made during 02:00 to 06:00 on January 5, 2009, at Hancun (39.4°N, 116.6°E), Langfang, Hebei in China. Quasi-monochromatic gravity waves (QMGWs) are found clearly in the observation data. Case studies show that their horizontal wavelengths, horizontal phase velocities, azimuth angles of horizontal propagation directions and periods of three QMGW examples are about 12.3 km, 41 m/s, 327°, 5 min; 25 km, 35 m/s, 68°, 12 min; and 10 km, 48 m/s, 341°, 3.5 min respectively.

Mesospheric gravity waves play important roles in atmospheric circulation and variability. It is meaningful to obtain the features of the mesospheric gravity waves on a global scale, such as the distribution and the sources. However, limited by the field of view, the ground-based instrument can only access some local information. We developed a space-borne imager to observe the global gravity waves by collecting the O2 airglow with TDI (Time Delayed and Integration) method. The function of the imager was testified in our laboratory with a led screen, where the gravity waves were simulated and shown. On a satellite orbit with the altitude of 700 km and inclination of 73 degree, the imager can obtain the gravity waves with horizontal wavelength more than 10 km, even taking the effect induced by the earth rotation into account.

The measurement of plasma displacement is one of the most basic diagnostic tools in the study of plasma equilibrium and control in a toroidal magnetic confinement configuration. During pulse discharge, the eddy current induced in the vacuum vessel and shell will produce an additional magnetic field at the plasma boundary, which will have a significant impact on the measurement of plasma displacement using magnetic probes. In the newly built Keda Torus eXperiment (KTX) reversed field pinch device, the eddy current in the composite shell can be obtained at a high spatial resolution. This device offers a new way to determine the plasma displacement for KTX through the multipole moment expansion of the eddy current, which can be obtained by unique probe arrays installed on the inner and outer surfaces of the composite shell. In an ideal conductor shell approximation, the method of multipole moment expansion of the poloidal eddy current for measuring the plasma displacement in toroidal coordinates, is more acc...

A system for electromagnetic measurements was designed and installed on the Keda Torus eXperiment (KTX) reversed field pinch device last year. Although the unique double-C structure of the KTX, which allows the machine to be opened easily without disassembling the poloidal field windings, makes the convenient replacement and modification of the internal inductive coils possible, it can present difficulties in the design of flux coils and magnetic probes at the two vertical gaps. Moreover, the KTX has a composite shell consisting of a 6 mm stainless steel vacuum chamber and a 1.5 mm copper shell, which results in limited space for the installation of saddle sensors. Therefore, the double-C structure and composite shell should be considered, especially during the design and installation of the electromagnetic diagnostic system (EDS). The inner surface of the vacuum vessel includes two types of probes. One type is for the measurement of the global plasma parameters, and the other type is for studying the local behavior of the plasma and operating the new saddle coils. In addition, the probes on the outer surface of the composite shell are used for measurements of eddy currents. Finally, saddle sensors for radial field measurements for feedback control were installed between the conducting shell and the vacuum vessel. The entire system includes approximately 1100 magnetic probes, 14 flux coils, 4×26×2 saddle sensors, and 16 Rogowski coils. Considering the large number of probes and limited space available in the vacuum vessel, the miniaturization of the probes and optimization of the probe distribution are necessary. In addition, accurate calibration and careful mounting of the probes are also required. The frequency response of the designed magnetic probes is up to 200 kHz, and the resolution is 1 G. The EDS, being spherical and of high precision, is one of the most basic and effective diagnostic tools of the KTX and meets the demands imposed by requirements on basic machine operating information and future studies.

Nonlinear cascade of low-frequency Alfvenic fluctuations (AFs) is regarded as one of the candidate energy sources that heat plasma during the non-adiabatic expansion of interplanetary coronal mass ejections (ICMEs). However, AFs inside ICMEs were seldom reported in the literature. In this study, we investigate AFs inside ICMEs using observations from Voyager 2 between 1 and 6 au. It has been found that AFs with a high degree of Alfvenicity frequently occurred inside ICMEs for almost all of the identified ICMEs (30 out of 33 ICMEs) and for 12.6% of the ICME time interval. As ICMEs expand and move outward, the percentage of AF duration decays linearly in general. The occurrence rate of AFs inside ICMEs is much less than that in ambient solar wind, especially within 4.75 au. AFs inside ICMEs are more frequently presented in the center and at the boundaries of ICMEs. In addition, the proton temperature inside ICME has a similar "W"-shaped distribution. These findings suggest significant contribution of AFs on local plasma heating inside ICMEs.

Evolution of volatile components during litchi (Litchi chinensis Sonn.) winemaking was monitored, and aroma profiles of litchi wines bottle aged for 5 months at ambient temperature (25-28 °C) and low temperature (8-10 °C) were compared via headspace solid phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The majority of terpenoids deriving from litchi juice decreased, even disappeared along with alcoholic fermentation, while terpenol oxides, ethers, and acetates came into being and increased. Ethyl octanote, isoamyl acetate, ethyl hexanoate, ethyl butanoate, cis-rose oxide, and trans-rose oxide had the highest odor activity values (OAVs) in young litchi wines. Six aromatic series were obtained by grouping OAVs of odor-active compounds with similar odor descriptions to establish the aroma profile for young litchi wines, and floral and fruity attributes were two major aroma series. Compared to ambient temperature when bottle aging, lower temperature benefited key aroma retention and expectantly extended the shelf life of young litchi wines.

The CSSAR airglow imager is developed to investigate the atmospheric gravity waves near the mesopause region. The CSSAR imager consists of a fisheye with a focal length of 10.5 mm and an F number of 2.8, three pieces of lenses for collimation, two filters, an imaging lens and a scientific CCD camera with 1024x1024 array, 24x24 micros pixels. Two filters for measuring the OH Meinel band (750-850nm) airglow layer peaking at 87 km and the O2 (865nm) airglow layer peaking at 90 km are used in the imager. Preliminary observation of the all-sky OH Meinel band airglow has been done during 02:00 to 06:00 on Jan. 5th, 2009, at Hancun (39.4°N, 116.6°E), Langfang, Hebei, which is the first time to image gravity wave in China. Case study shows that one quasi-monochromatic gravity wave has the horizontal wavelength of ~19 km, observed horizontal phase velocity of ~18 m/s, horizontal propagating azimuth direction of ~269° and observed period of ~18 min.

The Keda Torus eXperiment (KTX) is a medium-sized reversed field pinch (RFP) device under construction at the University of Science and Technology of China. The KTX has a major radius of 1.4 m and a minor radius of 0.4 m with an Ohmic discharge current up to 1 MA. The expected electron density and temperature are, respectively, 2 × 1019 m−3 and 800 eV. A combination of a stainless steel vacuum chamber and a thin copper shell (with a penetration time of 20 ms) surrounding the plasma provides an opportunity for studying resistive wall mode instabilities. The unique double-C design of the KTX vacuum vessel allows access to the interior of the KTX for easy first-wall modifications and investigations of power and particle handling, a largely unexplored territory in RFP research leading to demonstration of the fusion potential of the RFP concept. An active feedback mode control system is designed and will be implemented in the second phase of the KTX program. The recent progress of this program will be presented, including the design of the vacuum vessel, magnet systems and power supplies.