Optical design of a novel near-infrared phase contrast imaging(NI-PCI)diagnostic on the HL-2A tokamak

The optical design of near-infrared phase contrast imaging(NI-PCI)diagnosis on HL-2A is introduced in this paper.This scheme benefits from the great progress of near-infrared laser technology and is a broadening of traditional phase contrast technology.This diagnostic can work as a keen tool to measure plasma wavenumber spectra by inferring string-integrated plasma density fluctuations.Design of both the front optical path which is the path before the laser transmitting into the tokamak plasma and the rear optics which is the path after the laser passing through the plasma is detailed.The 1550 nm laser is chosen as the probe beam and highprecision optical components are designed to fit the laser beam,in which a phase plate with a 194-nm-deep silver groove is the key.Compared with the conventional 10.6μm laser-based PCI system on HL-2A,NI-PCI significantly overcomes the unwanted phase scintillation effect and promotes the measurement capability of high-wavenumber turbulence with an increased maximal measurable wavenumber from 15 cm^(-1)to 32.6 cm^(-1).

聚四氟乙烯微粉表面改性对氢化丁腈橡胶性能影响

采用甲基丙烯酸锌对聚四氟乙烯(PTFE)微粉进行改性,研究了改性后聚四氟乙烯对氢化丁腈橡胶力学性能、耐磨性能及与织物粘合性能的影响。结果表明,通过红外光谱仪和扫描电子显微镜发现PTFE颗粒表面包覆了一层甲基丙烯酸锌;随着甲基丙烯酸锌用量的增加,硫化胶的拉伸强度、撕裂强度和硬度增加;磨耗体积从71 mm^(3)降为28 mm^(3),胶料耐磨性得以改善;硫化胶与尼龙弹力布的剥离强度从1.8 N/mm提升到3.1 N/mm。综上所述,采用甲基丙烯酸锌改性PTFE能提高胶料的力学性能以及与织物之间的粘合强度,达到了改善聚四氟乙烯与橡胶之间粘合性能的目的。

Species composition and influencing factors of understory woody species in Robinia pseudoacacia plantations on the Loess Plateau

Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tablelands was significantly lower than in the gully stands.Regenerated black locust(19.76%)and Rubus corchorifolius L.f.(64.85%)were the most abundant understory tree and shrub species,respectively,in the tableland stands;Broussonetia papyrifera(L.)L’Hér.ex Vent.(6.77%)and Acanthopanax senticosus(Rupr.Maxim.)Harms.(37.22%)were most abundant in the gully stands.Species richness(S),Shannon diversity(H),and evenness index(J)of the understory plants were significantly lower in the tableland stands than in the gully stands.More diverse understory species and community structures occurred in the gully stands.Differences in species diversity among landform positions may be attributed to differences in soil moisture.In addition,77.57%of the variation in understory species composition was explained,among which shrub and herb coverage,stand age,leaf area index,slope and total soil phosphorus in the 10-20 cm layer were the main factors.Soil organic carbon and total potassium significantly impacted S,H and J.Considering the environmental conditions and the biological characteristics of the plants investigated,R.corchorifolius should be given priority in the development of tableland stands,while B.papyrifera and Celtis sinensis Pers.should form mixed forests with black locust in gully stands.This management could promote biodiversity and stability of the existing black locust plantations but also optimize regional landscape patterns.

Response of understory plant species richness and tree regeneration to thinning in Pinus tabuliformis plantations in northern China

Background:Chinese pine(Pinus tabuliformis Carr.)is one of the major afforestation species in northern China and plays a key role in restoring forest ecosystems and preserving soil and water.However,most Chinese pine plantations are experiencing ecological problems such as the low diversity of understory plants and difficulty in natural regeneration.Thinning has been widely used to maintain and improve a variety of forest ecosystem services from plantations.To date,however,few studies have been conducted to systematically determine the effects of thinning on understory plant diversity and the regeneration of Chinese pine in plantations.Methods:We conducted a literature search,and selected 22 publications covering a total of 83 treatments related to thinning effects on the species richness of understory plants and 15 publications covering a total of 43 treatments related to thinning effects on the regeneration of Chinese pine,in tree plantations of northern China.The data from the literature were synthesized and evaluated with meta-analysis approach to determine the treatment effects.Results:Compared with the control stands,thinning increased the species richness of shrubs and herbs by an average of 25.3%and 26.5%,respectively.While the varying thinning intensities all had significantly positive effects on the species richness of understory plants,only moderate thinning(30%–50%)had a positive effect on the density of regenerating seedlings and saplings of Chinese pine(60.2%).The species richness of understory plants was greatest after 14 years of thinning with an increase of 36.3%,whereas the density of regenerating Chinese pine seedlings and saplings reached a maximum after≥11 years of thinning with an increase of 76.5%,compared to that of the unthinned stands.Thinning in the half-mature plantations had the greatest effects on the understory shrub richness(44.1%)and the density of regenerating Chinese pine seedlings and saplings(86.5%).Both single and multiple thinning were found to significantly promote the species richness of understory plants and the density of regenerating Chinese pine seedlings and saplings,and the positive effects of thinning were greater in areas with a humidity index(HI)<30 than in areas with an HI≥30.In general,age group,planting density and recovery time were prominent factors affecting the species richness of understory plants,whereas the slope,HI and recovery time were the dominant controls of the density of regenerating Chinese pine seedlings and saplings,indicating differential effects of thinning on the species richness of understory plants and the regeneration capacity of Chinese pine in plantations.Conclusion:Thinning appears to be a feasible management measure to improve the understory plant diversity and regeneration capacity of Chinese pine in plantations.We postulate that moderate thinning in half-mature forest stands with an HI<30 can help effectively promote the species diversity of understory plants and the natural regeneration of Chinese pine,thereby maintaining a more resilient stand structure and the development of Chinese pine plantations.

Effect of ideal internal MHD instabilities on NBI fast ion redistribution in ITER 15 MA scenario

Transport of fast ions is a crucial issue during the operation of ITER.Redistribution of neutral beam injection(NBI)fast ions by the ideal internal magnetohydrodynamic(MHD)instabilities in ITER is studied utilizing the guiding-center code ORBIT(White R B and Chance M S 1984Phys.Fluids 272455).Effects of the perturbation amplitude A of the internal kink,the perturbation frequency f of the fishbone instability,and the toroidal mode number n of the internal kink are investigated,respectively,in this work.The n=1 internal kink mode can cause NBI fast ions transporting in real space from regions of 0<s≤0.32 to 0.32<s≤0.53,where s labels the normalized plasma radial coordinate.The transport of fast ions is greater as the perturbation amplitude increases.The maximum relative change of the number of fast ions approaches 5%when the perturbation amplitude rises to 500 G.A strong transport is generated between the regions of 0<s≤0.05 and 0.05<s≤0.12 in the presence of the fishbone instability.Higher frequency results in greater transport,and the number of fast ions in 0<s≤0.05 is reduced by 30%at the fishbone frequency of 100 k Hz.Perturbations with higher n will lead to the excursion of fast ion transport regions outward along the radial direction.The loss of fast ions,however,is not affected by the internal MHD perturbation.Strong transport from 0<s≤0.05 to 0.05<s≤0.12 does not influence the plasma heating power of ITER,since the NBI fast ions are still located in the plasma core.On the other hand,the influence of fast ion transport from 0<s≤0.32 to 0.32<s≤0.53 needs further study.

Summary of the 10th Conference on Magnetically Confined Fusion Theory and Simulation(CMCFTS)

This paper gives a summary of the organization and the presentations delivered at the 10th Conference on Magnetically Confined Fusion Theory and Simulation(CMCFTS)held in Zhuhai,China,from 28th to 31st October 2022.The conference focused on the latest progress in the research of the magnetic confined fusion plasma theory and simulations,as well as the largescale numerical simulation techniques developed in recent years.This conference is held both online and offline,with about 110 domestic participants from 18 institutes participating in the live conference,and the statistical data from the live broadcast platform indicated that the online conference attracted over 20000 views per day.A summary of the conference is given,and the history of the CMCFTS is presented.A brief introduction to the poster section is also included in this paper.

Liquid-liquid two-phase flow in a wire-embedded concentric microchannel: Flow pattern and mass transfer performance

In this work, flow pattern and mass transfer of liquid-liquid two-phase flow in a wire-embedded concentric microchannel are studied using toluene-water system. Droplet flow, slug flow, oval flow and annular flow are observed in the wire-embedded concentric microchannel. The effects of embedded wires and physical properties on flow patterns are investigated. The embedded wire insert is conducive to the formation of annular flow. The flow pattern distribution regions are distinguished by the Caaq(capillary number)±We_(org)(Weber number) flow pattern map. When Weorg<0.001, slug flow is the main flow pattern, and when Weorg>0.1, annular flow is the main flow pattern. Oval flow and droplet flow are between We_(org)= 0.001-0.1, and oval flow is transformed into droplet flow with the increase of Caaq. The effect of flow rate, phase ratio, initial acetic acid concentration, insert shape and flow patterns on mass transfers are studied. Mass transfer process is enhanced under annular flow conditions, the volumetric mass transfer coefficient is up to 0.36 s^(-1) because of the high interfacial area and interface renewal rate of annular flow.

Preparation of a beam emission spectroscopy diagnostic based on a Lyman-alpha line to diagnose core and edge-plasma density fluctuation on the HL-2A tokamak

In this article,the design of a Lyman-alpha-based beam emission spectroscopy(LAB)diagnostic on the HL-2A tokamak has been proposed for the first time.The purpose of this novel diagnostic is to measure density fluctuations of tokamak plasma.The light-collection system of LAB,which consists of the first mirror and two groups of coaxial double-mirror telescopes,can realize a twosegmented viewing field ofρ=0–0.2 andρ=0.75–1,which is optimized to measure plasma density fluctuation,not only in the edge transport barrier region but also in the internal transport barrier region,to investigate the underlying physics of turbulence in tokamaks.Spectrometers are developed to separate out the Doppler-shifted target line(122.03 and 122.17 nm)from the background Lyman-alpha line(121.53 nm).Here,30 Core-LAB channels and 30 Edge-LAB channels are under development on the HL-2A tokamak.It has high radial spatial resolutions of about 2.7 mm and 3.3 mm for the core and edge channels,respectively.Taking the high light intensity of this Lyman-alpha line into account,temporal resolution of 200 k Hz can be ensured by broad bandwidth amplifiers.This high spatio-temporal resolution makes LAB a potential keen tool to experimentally investigate tokamak plasma physics.

Conceptual design of the three-dimensional magnetic field configuration relevant to the magnetopause reconnection in the SPERF

A new ground-based expenmental device,the Space Plasma Environment Research Facility（SPERF）,is being designed at Harbin Institute of Technology in China,with Asymmetric REconnection eXperiment-3 Dimensional（AREX-3D） as one of the experimental components to study the asymmetric reconnection dynamics relevant to the interaction between the interplanetary and magnetospheric plasmas.The asymmetry in the designed magnetic reconnection process not only refers to the distinct plasma parameters designed for the two upstream regions across the current sheet,but also refers to the inhomogeneity in the direction along the current sheet resulting from the designed 3D magnetic field geometry.These two asymmetries are fundamental features of the reconnection process at the Earth＇s magnetopause.In experiment,the reconnection process is driven by a set of flux cores through coil-currentramp-up from the ＇magnetosheath-side＇ to interact with a dipole magnetic field generated by the Dipole Research Experiment（DREX） coil on the ＇magnetosphere-side＇.The AREX-3D will be able to investigate a range of important reconnection issues in 3D magnetic field geometry that is relevant to the Earth＇s magnetopause.A wide range of plasma parameters can be achieved through inductive plasma generation with flux cores on the ＇magnetosheath-side＇ and electron cyclotron resonance（ECR） with microwave sources on the ＇magnetosphere-side＇,e.g.high（low）plasma density at experimental magnetosheath（dipole） side.Different reconnection regimes and geometries can be produced by adjusting plasma parameters and coil setups as well as coil current waveforms.The three-dimensional magnetic field configurations in the SPERF relevant to the dayside magnetopause reconnection are discussed in detail.

Nonlinear evolution and secondary island formation of the double tearing mode in a hybrid simulation

Double tearing modes(DTMs),induced by double current sheet configurations or two neighboring rational surfaces with the same safety factor in tokamaks,are widely observed in solar,space,and fusion plasmas.In this paper,the evolution of DTMs without a guide field is investigated numerically using a hybrid model(electron fluid+ion PIC).The overall evolution processes of DTMs are qualitatively consistent with previous works using other models.The particle dynamics during the evolution of DTMs is analyzed in detail.Behaviors of ions and electrons present different characteristics around the reconnection region which gives rise to Hall effects producing the out-of-plane quadrupole magnetic field.In the explosive reconnection process with interactions between two DTMs islands,the asymmetric drive and the thin current layer feature lead to the emergence of secondary magnetic islands which develop with the late evolution of the DTMs.

Conceptual design of Dipole Research Experiment(DREX)

A new terrella-like device for laboratory simulation of inner magnetosphere plasmas,Dipole Research Experiment,is scheduled to be built at the Harbin Institute of Technology（HIT）,China,as a major state scientific research facility for space physics studies.It is designed to provide a ground experimental platform to reproduce the inner magnetosphere to simulate the processes of trapping,acceleration,and transport of energetic charged particles restrained in a dipole magnetic field configuration.The scaling relation of hydromagnetism between the laboratory plasma of the device and the geomagnetosphere plasma is applied to resemble geospace processes in the Dipole Research Experiment plasma.Multiple plasma sources,different kinds of coils with specific functions,and advanced diagnostics are designed to be equipped in the facility for multi-functions.The motivation,design criteria for the Dipole Research Experiment experiments and the means applied to generate the plasma of desired parameters in the laboratory are also described.

Integrated data analysis on the electron temperature profile of HL-2A with the Bayesian probability inference method

Data analysis on tokamak plasmas is mainly based on various diagnostic systems,which are usually modularized and independent of each other.This leads to a large amount of data not being fully and effectively exploited so that it is not conducive to revealing the deep physical mechanism.In this work,Bayesian probability inference with machine learning methods have been applied to the electron cyclotron emission and Thomson scattering diagnostic systems on HL-2A/2M,and the effects of integrated data analysis(IDA)on the electron temperature of HL-2A with Bayesian probability inference are demonstrated.A program is developed to infer the whole electron temperature profile with a confidence interval,and the program can be applied in online analysis.The IDA results show that the full profile of the electron temperature can be obtained and the diagnostic information is more comprehensive and abundant with IDA.The inference models for electron temperature analysis are established and the developed programs will serve as an experimental data analysis tool for HL-2A/2M in the near future.

TALEN-Mediated FLAG-Tagging of Endogenous Histone Methyltransferase DOT1L

Histone modification including H3 lysine 79 methylation (H3K79me) plays a key role during gene transcription and DNA damage repair. DOT1L, the sole methyltransferase for three states of H3K79me, is implicated in leukemia, colorectal cancer, and dilated cardiomyopathy. However, understanding of DOT1L and H3K79me in these pathways and disease pathogenesis has been limited due to the difficulty of working with DOT1L protein. For instance, locus-specific or genome-wide binding sites of DOT1L revealed by chromatin immunoprecipitation (ChIP)-based methods are necessary for inferring its functions, but high-quality ChIP-grade antibodies are currently not available. Herein we have developed a knock-in approach to tag endogenous DOT1L with 3 × Flag at its C-terminal domain to follow functional analyses. The knock-in was facilitated by using TALENs to induce a targeted double-strand break at the endogenous DOTIL to stimulate local homologous recombination at that site. The single cell colonies with successful knock-in were isolated and verified by different methods. We also demonstrated that tagged DOT1L maintains its normal function in terms of methylation and that the engineered cells would be very useful for further studies.

Yangtze River Delta Aerosol liquid water in PM_(2.5)and its roles in secondary aerosol formation at a regional site of Yangtze River Delta

Aerosol liquid water content(ALWC)plays an important role in secondary aerosol formation.In this study,a whole year field campaign was conducted at Shanxi in north Zhejiang Province during 2021.ALWC estimated by ISORROPIA-Ⅱ was then investigated to explore its characteristics and relationship with secondary aerosols.ALWC exhibited a highest value in spring(66.38μg/m^(3)),followed by winter(45.08μg/m^(3)),summer(41.64μg/m^(3)),and autumn(35.01μg/m^(3)),respectively.It was supposed that the secondary inorganic aerosols(SIA)were facilitated under higher ALWC conditions(RH>80%),while the secondary organic species tended to form under lower ALWC levels.Higher RH(>80%)promoted the NO_(3)^(-)formation via gas-particle partitioning,while SO_(4)^(2-)was generated at a relative lower RH(>50%).The ALWC was more sensitive to NO_(3)^(-)(R=0.94)than SO_(4)^(2-)(R=0.90).Thus,the self-amplifying processes between the ALWC and SIA enhanced the particle mass growth.The sensitivity of ALWC and OX(NO_(2)+O_(3))to secondary organic carbon(SOC)varied in different seasons at Shanxi,more sensitive to aqueous-phase reactions(daytime R=0.84;nighttime R=0.54)than photochemical oxidation(daytime R=0.23;nighttime R=0.41)in wintertime with a high level of OX(daytime:130-140μg/m^(3);nighttime:100-140μg/m^(3)).The self-amplifying process of ALWC and SIA and the aqueous-phase formation of SOC will enhance aerosol formation,contributing to air pollution and reduction of visibility.

Clinical antitumor application and pharmacological mechanisms of Dahuang Zhechong Pill

Cancer still has elevated morbidity and mortality,which undoubtedly impacts the life quality of affected individuals.Remarkable advances have been made in cancer therapy,although the toxicities of traditional therapies remain an obvious challenge.Dahuang Zhechong Pill(DHZCP),developed by Zhongjing Zhang in the Synopsis of the Golden Chamber,represents an effective anticancer traditional Chinese medicine(TCM).In this review,it was found that DHZCP is therapeutically utilized in liver,lung,gastric,pancreatic and other cancers in clinic.Pharmacological evidence showed that its anti-tumor mechanisms mainly involve induced cell cycle arrest,apoptosis and autophagy,as well as suppressed tumor cell proliferation,obstructed angiogenesis and metastasis,enhanced immunity,and reversal of multidrug resistance.The present review provides a solid basis for the clinical application of DHZCP and may promote the wide use of TCM in clinical antitumor application.

Thermocapillary flow-induced core release from double-emulsion droplets in microchannels

The use of double emulsions(DEs),which represent colloidal structures composed of droplets nested within droplets,can provide for unparallel droplet manipulation in droplet-based microfluidic technology due to their unique core–shell structures.The controlled release of cores in DEs is of particular interest.However,this process remains poorly explored.In this work,the thermocapillary flow induced by a temperature gradient is used as a driving force to control the core release and the impacts of different linear temperature gradients,core diameters,shell diameter,and core/shell diameter ratios on the thermocapillary flow and core release characteristics of DE droplets consisting of a water-in-n-hexadecane-in-water system within a cylindrical microchannel are investigated.Most of the core and shell diameter conditions considered result in a double-core release process,where the inner droplet volume is partially ejected before the remaining core is rewrapped by the outer droplet,and the remaining inner droplet volume is ejected later during a second core release event.However,relatively small core diameters of 50 and 75μm produce conditions where the full inner droplet volume is ejected during a singlecore release process.In addition,we provide empirical relationships for accurately determining the time at which core release initially occurs under given DE parameters as well as for precisely determining whether the applied conditions will lead to single-or double-core release processes.Therefore,the results of this study provide insights enabling the development of accurate inner droplet release technologies under thermocapillary migration.

Alterations of Audiovisual Integration in Alzheimer’s Disease

Audiovisual integration is a vital information process involved in cognition and is closely correlated with aging and Alzheimer’s disease(AD).In this review,we evaluated the altered audiovisual integrative behavioral symptoms in AD.We further analyzed the relationships between AD pathologies and audiovisual integration alterations bidirectionally and suggested the possible mechanisms of audiovisual integration alterations underlying AD,including the imbalance between energy demand and supply,activity-dependent degeneration,disrupted brain networks,and cognitive resource overloading.Then,based on the clinical characteristics including electrophysiological and imaging data related to audiovisual integration,we emphasized the value of audiovisual integration alterations as potential biomarkers for the early diagnosis and progression of AD.We also highlighted that treatments targeted audiovisual integration contributed to widespread pathological improvements in AD animal models and cognitive improvements in AD patients.Moreover,investigation into audiovisual integration alterations in AD also provided new insights and comprehension about sensory information processes.

滇杨种群遗传多样性与遗传结构

滇杨(Populus yunnanensis)是我国西南地区的特有树种,具有速生、易无性繁殖、适应性强等优良特性,是典型的南方型杨属树种。研究滇杨遗传多样性及种群结构对其种质资源的收集、保存和利用具有重要的意义。本研究从我国滇杨主要分布区云南和四川共采集了6个种群,包括云南的昭通(ZT)、会泽(HZ)、嵩明(SM)、洱源(EY)、拉市海(LS)以及四川的美姑(MG),共64个个体,利用34对SSR分子标记和3对cp DNA叶绿体标记开展遗传多样性与遗传结构研究。SSR引物共检测到154个等位基因,平均等位基因数为4.529,观测杂合度(Ho)与期望杂合度(He)分别为0.552和0.472,遗传分化系数(Fst)平均值为0.238,多态性信息含量指数(PIC)平均值为0.421,基因流(Nm)为0.806。滇杨的遗传结构分析(DAPC)与遗传距离的主坐标分析(PCo A)、UPGMA聚类分析均将6个种群划分为3个亚类:第?亚类包括昭通种群、会泽种群和嵩明种群的4个个体,第??亚类包括嵩明种群的6个个体以及洱源种群和拉市海种群,第III亚类为美姑种群;嵩明种群包含第?和第??两个亚类的混合遗传成分。3个cp DNA联合序列中共检测到35个变异位点,分为13个单倍型,其中单倍型H5在种群中分布最为广泛,其余的单倍型均为种群特有的单倍型。分子方差分析(AMOVA)表明种群内的遗传变异大于种群间变异。研究表明滇杨不同种群的遗传分化具有地域性,可选择就地保护;昭通种群遗传多样性最高,且包含7种叶绿体单倍型,单倍型类型最多,应优先保护。

Lactate metabolism in human health and disease

The current understanding of lactate extends from its origins as a byproduct of glycolysis to its role in tumor metabolism,as identified by studies on the Warburg effect.The lactate shuttle hypothesis suggests that lactate plays an important role as a bridging signaling molecule that coordinates signaling among different cells,organs and tissues.Lactylation is a posttranslational modification initially reported by Professor Yingming Zhao’s research group in 2019.Subsequent studies confirmed that lactylation is a vital component of lactate function and is involved in tumor proliferation,neural excitation,inflammation and other biological processes.An indispensable substance for various physiological cellular functions,lactate plays a regulatory role in different aspects of energy metabolism and signal transduction.Therefore,a comprehensive review and summary of lactate is presented to clarify the role of lactate in disease and to provide a reference and direction for future research.This review offers a systematic overview of lactate homeostasis and its roles in physiological and pathological processes,as well as a comprehensive overview of the effects of lactylation in various diseases,particularly inflammation and cancer.

Utility of susceptibility-weighted imaging in Parkinson’s disease and atypical Parkinsonian disorders

In the clinic,the diagnosis of Parkinson’s disease(PD)largely depends on clinicians’experience.When the diagnosis is made,approximately 80%of dopaminergic cells in the substantia nigra(SN)have been lost.Additionally,it is rather challenging to differentiate PD from atypical parkinsonian disorders(APD).Clinially-available 3T conventional MRI contributes little to solve these problems.The pathologic alterations of parkinsonism show abnormal brain iron deposition,and therefore susceptibility-weighted imaging(SWI),which is sensitive to iron concentration,has been applied to find iron-related lesions for the diagnosis and differentiation of PD in recent decades.Until now,the majority of research has revealed that in SWI the signal intensity changes in deep brain nuclei,such as the SN,the putamen(PUT),the globus pallidus(GP),the thalamus(TH),the red nucleus(RN)and the caudate nucleus(CN),thereby raising the possibility of early diagnosis and differentiation.Furthermore,the signal changes in SN,PUT and TH sub-regions may settle the issues with higher accuracy.In this article,we review the brain iron deposition of PD,MSA-P and PSP in SWI in the hope of exhibiting a profile of SWI features in PD,MSA and PSP and its clinical values.