Inversion techniques to obtain local rotation velocity and ion temperature profiles for the x-ray crystal spectrometer on EAST

Inversion techniques are conducted based on the tangential x-ray crystal spectroscopy(TXCS)geometry on EAST to obtain the local profiles of ion temperature(Ti)and toroidal rotation velocity(vt).Firstly,local emissivity profiles of the impurity argon are obtained using the asymmetrical Abel inversion.Then,the local vt and Ti profiles are calculated by considering the local emissivity profiles and the TXCS detailed geometry.In addition,how the changes in the vt profiles affect the accuracy in the Ti profiles is discussed in detail.It is also found that the lineintegrated Ti profiles are becoming less accurate with the increase in the radial gradient in the local vt profiles.Nonetheless,accurate Ti radial profiles are reconstructed after considering the effects of the emissivity and velocity,which are verified by comparing the inverted vt and Ti profiles with those local profile measurements from the Charge eXchange Recombination Spectroscopy(CXRS)on EAST.

Development of an upgraded motional Stark effect diagnostic system on EAST tokamak

A new multi-channel motional Stark effect(MSE)diagnostic system has been developed on the upgraded EAST tokamak,which was installed on the port C to observe a tangential neutral beam.A telecentric imaging lens was deployed to ensure uniform illumination from the core to the boundary.A square fiber head which contained 23 fiber bundles was mounted to this imaging lens;each fiber bundle contained 19 fibers and two of them were assigned to CXRS and BES spectrometer,respectively.The angle tuning method was used for matching the Doppler shift of theσcomponent’s wavelength which was caused by the beam voltage.At the present stage,the MSE system only contains ten channels that would be extended to 23 channels in the future,covering a measurement range from R=1.8 to R=2.27 m with a temporal resolution of 10 ms and a spatial resolution of3 cm.The polarization angle-constrained q profiles and current density profiles were reconstructed with EFIT equilibrium reconstructions.In the sawtooth discharges,the q=1 surface position was validated by the ECE signals,which further verified the rationality of the MSE measurement.

Adrenal pheochromocytoma impacts three main pathways: cysteine-methionine, pyrimidine, and tyrosine metabolism

Pheochromocytomas and paragangliomas(PPGLs)cause symptoms by altering the circulation levels of catecholamines and peptide hormones.Currently,the diagnosis of PPGLs relies on diagnostic imaging and the detection of catecholamines.In this study,we used ultra-performance liquid chromatography(UPLC)/quadrupole time-of-flight mass spectrometry(Q-TOF MS)analysis to identify and measure the perioperative differential metabolites in the plasma of adrenal pheochromocytoma patients.We identified differentially expressed genes by comparing the transcriptomic data of pheochromocytoma with the normal adrenal medulla.Through conducting two steps of metabolomics analysis,we identified 111 differential metabolites between the healthy group and the patient group,among which 53 metabolites were validated.By integrating the information of differential metabolites and differentially expressed genes,we inferred that the cysteine-methionine,pyrimidine,and tyrosine metabolism pathways were the three main metabolic pathways altered by the neoplasm.The analysis of transcription levels revealed that the tyrosine and cysteine-methionine metabolism pathways were downregulated in pheochromocytoma,whereas the pyrimidine pathway showed no significant difference.Finally,we developed an optimized diagnostic model of two metabolites,L-dihydroorotic acid and vanylglycol.Our results for these metabolites suggest that they may serve as potential clinical biomarkers and can be used to supplement and improve the diagnosis of pheochromocytoma.

Geology and mineralization of the Songpan-Ganze-West Kunlun pegmatite-type rare-metal metallogenic belt in China:An overview and synthesis

The Songpan-Ganze orogenic belt on the northeastern margin of the Tibetan Plateau extends westward from the Songpan-Ganze terrain in western Sichuan to the Tianshuihai region in West Kunlun,Xinjiang.It hosts numerous giant spodumene pegmatite deposits and ore fields,including Jiajika and Ke’eryin in western Sichuan Province,Zhawulong on the border between the Sichuan and Qinghai Provinces,and Dahongliutan in Xinjiang Region.These form the Songpan-Ganze-West Kunlun(SP-GZ-WK) pegmatite-type rare-metal metallogenic belt.The pegmatite type rare-metal deposits in this belt are hosted in the metamorphic thermal domes in the metamorphosed flysh of the Triassic Xikang and Bayankalashan Groups.The mineralized pegmatites are intimately related to the Li-and volatile-rich two-mica granites that are peraluminous and have high(Li+Na+K)/(Mn+Fe+Mg+Ca+Ti) ratios.Pegmatites and granites in individual ore field throughout the belt typically form a cogenetic granite-pegmatite system,in which pegmatite dikes commonly surround granites.Spodumene is the predominant ore mineral in most pegmatites with limited hydrothermal alteration.In the granite-pegmatite systems,granitic magmas were emplaced under P-T conditions of 800–850°C and ~550 MPa,while spodumene crystallized in an alkaline environment.The granite-pegmatite systems share similar Sr-Nd-Hf-Li isotopic compositions to the metasediments of the Xikang and Bayankalashan Groups.The δ7Li values tend to increase from the granites to the Li-poor pegmatites,whereas the reverse is observed between the Li-poor and Li-rich pegmatites.These geochronological data suggest that the granite-pegmatite systems formed in the Late Triassic and tend to be progressively younger from the outer to the inner zones of the metallogenic belt.These characteristics show that the granitic-pegmatitic melts were derived from the anatexis of the Xikang and Bayankalashan Groups during the Paleo-Tethyan orogeny in the Late Triassic.The separation of pegmatitic melts from granitic magmas can be best explained using the Jiajika-style “melt-melt immiscibility” or the Ke’eryin-style “fractional crystallization+melt-melt immiscibility” model.High-maturity terrestrial sediments are of key importance for the anatexis that results in the granitepegmatite melts.The bidirectional tectonic stresses in the Songpan-Ganze orogenic belt may have caused the mineralization difference between the Jiajika deposit and the Ke’eryin ore field.These features indicate the controls of the combination of orogenic deformation,metapelites anatexis,and magmatic differentiation on the rare-metal mineralization of pegmatites.We suggest that pegmatites,pegmatite–parental granite,and their protoliths are important indicators for rare-metal mineralization in the SP-GZ-WK pegmatite type rare-metal metallogenic belt.Based on the widespread presence of fertile metasediments and well development of metamorphic thermal dome,highly differentiated granites,and regional zonation of pegmatites,the Zhawulong ore field is the most prospective area for rare metals and thus should be the priority for future exploration.

Determination of ifenprodil by LC–MS/MS and its application to a pharmacokinetic study in healthy Chinese volunteers

This paper reports the development and validation of an assay for ifenprodil based on liquid chromatography–tandem mass spectrometry(LC–MS/MS)and its application to a pharmacokinetic study involving single and multiple intravenous infusions to healthy Chinese volunteers.After sample preparation of plasma by liquid–liquid extraction with ethyl acetate,the analyte and internal standard,urapidil,were separated by reversed phase chromatography in a run time of 4 min and detected by positive ion electrospray ionization followed by multiple reaction monitoring of the precursor-to-product ion transitions at m/z 326.2-308.1 for ifenprodil and m/z 388.4-205.3 for IS.The assay was linear in the concentration range 0.2–50.0 ng/mL with recovery 476.4%.In the pharmacokinetic study of single intravenous infusions of 5,10 and 15 mg ifenprodil,peak plasma concentrations and areas under the plasma concentration–time curve were both linearly related to dose.In the pharmacokinetic study of multiple once daily intravenous infusions of 10 mg ifenprodil for 7 days,pharmacokinetic parameters were similar to those after the single dose showing that ifenprodil does not accumulate on repeated administration.

地外文明技术印迹射电搜寻进展

基于哥白尼原理、德雷克公式以及大量系外行星的发现,大多科学家相信地球之外一定存在着生命尤其是高级智慧生命(或文明).射电技术由于其优势而成为地外文明搜寻的最佳手段之一.“中国天眼”(FAST)是全世界最大的单天线射电望远镜,地外文明搜寻(search for extraterrestrial intelligence,SETI)是其五大科学目标之一,它在低频射电L波段上极高的灵敏度对SETI有着重要意义.基于FAST专门用于SETI观测的后端设备和正式申请的观测时间,我们开展了SETI后端共时巡天观测和系外行星目标观测.与加利福尼亚大学伯克利分校的在家地外文明搜寻(SETI@home)和突破聆听(Breakthrough Listen)团队合作,我们发展了SETI目标观测多波束匹配模式以及使地外文明(extraterrestrial intelligence,ETI)信号鉴别过程更加科学完备的偏振和频率漂移判据,实施了观测和数据处理来筛选ETI候选目标.本文主要介绍国际上的SETI观测历史,尤其是FAST进行SETI的研究现状和最新进展以及未来展望.

A single-cell atlas of mouse olfactory bulb chromatin accessibility

Olfaction,the sense of smell,is a fundamental trait crucial to many species.The olfactory bulb(OB)plays pivotal roles in processing and transmitting odor information from the environment to the brain.The cellular heterogeneity of the mouse OB has been studied using single-cell RNA sequencing.However,the epigenetic landscape of the m OB remains mostly unexplored.Herein,we apply single-cell assay for transposaseaccessible chromatin sequencing to profile the genome-wide chromatin accessibility of 9,549 single cells from the m OB.Based on single-cell epigenetic signatures,m OB cells are classified into 21 clusters corresponding to 11 cell types.We identify distinct sets of putative regulatory elements specific to each cell cluster from which putative target genes and enriched potential functions are inferred.In addition,the transcription factor motifs enriched in each cell cluster are determined to indicate the developmental fate of each cell lineage.Our study provides a valuable epigenetic data set for the m OB at single-cell resolution,and the results can enhance our understanding of regulatory circuits and the therapeutic capacity of the OB at the single-cell level.

中国铌钽矿成矿规律

铌、钽是世界新兴产业发展的关键性金属资源.世界上的铌钽资源主要为内生来源,可分为过铝质岩浆系统的花岗伟晶岩型和花岗岩型铌钽矿床、碱性岩-碳酸岩岩浆系统的碳酸岩及其风化壳型和碱性岩型铌钽资源.我国的铌钽资源主要为花岗岩型、花岗伟晶岩型、碱性岩型和碳酸岩型,但资源品位较低,碳酸岩型铌钽资源较少,尚未发现碳酸岩风化壳型资源.我国过铝性岩浆系统的铌钽矿床主要分布在阿尔泰、松潘-甘孜、江南古陆、南岭和滇西-藏南等铌钽成矿带,成矿作用集中在加里东期、印支期和燕山期,并有少量发生在喜山期;碱性系统的铌钽成矿带主要为塔里木-华北北缘、秦岭和扬子西缘成矿带,成矿主要发生在海西-印支期,并有元古宙的成矿作用,两种类型成矿系统的时空分离交替成矿的特征主要归因于二者具有不同的成矿构造背景.前者主要发生在具有巨厚复理石沉积建造的造山带,造山过程中发生铌钽成矿作用;后者主要发生在深大断裂带或裂谷区,成矿物质具有深部来源特征.在今后的找矿工作中,我国应该在松潘-甘孜、阿尔泰、江南古陆、藏南等巨厚复理石沉积建造区,加大寻找高品位花岗伟晶岩型铌钽资源的力度;在塔里木-华北陆块北缘和秦岭等深大断裂发育区,寻找碳酸岩型铌资源;重视南岭、滇西和秦岭地区钨锡矿床中共(伴)生的铌钽资源,加强综合利用研究.

Single-cell brain atlas of Parkinson's disease mouse model

Parkinson's disease(PD)is a neurodegenerative disease,leading to the impairment of movement execution.PD pathogenesis has been largely investigated,either limited to bulk transcriptomic levels or at certain cell types,which failed to capture the cellular heterogeneity and intrinsic interplays among distinct cell types.Here,we report the application of single-nucleus RNA-seq on midbrain,striatum,and cerebellum of theα-syn-A53 T mouse,a well-established PD mouse model,and matched controls,generating the first single cell transcriptomic atlas for the PD model mouse brain composed of 46,174 individual cells.Additionally,we comprehensively depicte the dysfunctions in PD pathology,covering the elevation of NF-k B activity,the alteration of ion channel components,the perturbation of protein homeostasis network,and the dysregulation of glutamatergic signaling.Notably,we identify a variety of cell types closely associated with PD risk genes.Taken together,our study provides valuable resources to systematically dissect the molecular mechanism of PD pathogenesis at the single-cell resolution,which facilitates the development of novel approaches for diagnosis and therapies against PD.

家猪大脑皮层和下丘脑单细胞转录组图谱

家猪(Sus scrofa domesticus)的大脑由于与人的相似性而备受关注.但是,家猪脑组织细胞的组成尚不明确.该研究构建了家猪脑组织5个脑区(额叶、顶叶、颞叶、枕叶和下丘脑)的单细胞转录组图谱,并鉴定了21个细胞类群.通过家猪和小鼠下丘脑的跨物种比较,揭示了在单细胞分辨率下家猪和小鼠2个物种间保守的和特异的基因表达模式.此外,该研究还鉴定了与神经系统疾病密切相关的细胞类型和分子途径,弥补了基因突变和发病机制之间的空缺.该研究绘制了首个家猪大脑皮层和下丘脑的单细胞转录组图谱,并结合跨物种比较,为神经科学、演化发育生物学和再生医学的研究提供了宝贵的资源.