Spatially resolved transcriptomic profiling of placental development in dairy cow

The placenta plays a crucial role in successful mammalian reproduction.Ruminant animals possess a semi-invasive placenta characterized by a highly vascularized structure formed by maternal endometrial caruncles and fetal placental cotyledons,essential for full-term fetal development.The cow placenta harbors at least two trophoblast cell populations:uninucleate(UNC)and binucleate(BNC)cells.However,the limited capacity to elucidate the transcriptomic dynamics of the placental natural environment has resulted in a poor understanding of both the molecular and cellular interactions between trophoblast cells and niches,and the molecular mechanisms governing trophoblast differentiation and functionalization.To fill this knowledge gap,we employed Stereo-seq to map spatial gene expression patterns at near single-cell resolution in the cow placenta at 90 and 130 days of gestation,attaining high-resolution,spatially resolved gene expression profiles.Based on clustering and cell marker gene expression analyses,key transcription factors,including YBX1 and NPAS2,were shown to regulate the heterogeneity of trophoblast cell subpopulations.Cell communication and trajectory analysis provided a framework for understanding cell-cell interactions and the differentiation of trophoblasts into BNCs in the placental microenvironment.Differential analysis of cell trajectories identified a set of genes involved in regulation of trophoblast differentiation.Additionally,spatial modules and co-variant genes that help shape specific tissue structures were identified.Together,these findings provide foundational insights into important biological pathways critical to the placental development and function in cows.

离心透平转子的动力学分析与试验

针对某离心式透平膨胀机转子,采用MADYN2000进行动力学建模,对高速轴进行了无阻尼临界转速分析与临界转速图谱分析,选定了轴承刚度范围。确定轴承结构后校验了轴承的动态特性,该轴系的阻尼临界转速满足API617设计要求,并用不平衡响应计算为叶顶密封间隙设计提供了依据。在机组试验过程中,可重复观察到显著的跨临界现象,并对试验期间出现的油膜涡动情况进行了剖析。达到额定转速后的轴承振动趋于良好,经停机拆解未发现叶顶密封有磨损痕迹。试验结果表明,离心透平转子的临界转速和轴承温度计算与试验结果基本吻合,转子动力学分析在新机组的开发过程中具有良好的指导意义。

Intracellular accumulation of tau inhibits autophagosome formation by activating TIA1-amino acid-mTORC1 signaling

Background:Autophagy dysfunction plays a crucial role in tau accumulation and neurodegeneration in Alzheimer’s disease(AD).This study aimed to investigate whether and how the accumulating tau may in turn affect autophagy.Methods:The primary hippocampal neurons,N2a and HEK293T cells with tau overexpression were respectively starved and treated with vinblastine to study the effects of tau on the initiating steps of autophagy,which was analysed by Student’s two-tailed t-test.The rapamycin and concanamycin A were employed to inhibit the mammalian target of rapamycin kinase complex 1(mTORC1)activity and the vacuolar H+-ATPase(v-ATPase)activity,respectively,which were analysed by One-way ANOVA with post hoc tests.The Western blotting,co-immunoprecipitation and immunofuorescence staining were conducted to gain insight into the mechanisms underlying the tau effects of mTORC1 signaling alterations,as analysed by Student’s two-tailed t-test or One-way ANOVA with post hoc tests.The autophagosome formation was detected by immunofuorescence staining and transmission electron microscopy.The amino acids(AA)levels were detected by high performance liquid chromatography(HPLC).Results:We observed that overexpressing human full-length wild-type tau to mimic AD-like tau accumulation induced autophagy deficits.Further studies revealed that the increased tau could bind to the prion-related domain of T cell intracellular antigen 1(PRD-TIA1)and this association significantly increased the intercellular level of amino acids(Leucine,P=0.0038;Glutamic acid,P=0.0348;Alanine,P=0.0037;Glycine,P=0.0104),with concordant upregulation of mTORC1 activity[phosphorylated eukaryotic translation initiation factor 4E-binding protein 1(p-4EBP1),P<0.0001;phosphorylated 70 kD ribosomal protein S6 kinase 1(p-p70S6K1),P=0.0001,phosphorylated unc-51-like autophagyactivating kinase 1(p-ULK1),P=0.0015]and inhibition of autophagosome formation[microtubuleassociated protein light chain 3 II(LC3 II),P=0.0073;LC3 puncta,P<0.0001].As expected,this tau-induced deficit of autophagosome formation in turn aggravated tau accumulation.Importantly,we also found that blocking TIA1 and tau interaction by overexpressing PRD-TIA1,downregulating the endogenous TIA1 expression by shRNA,or downregulating tau protein level by a small proteolysis targeting chimera(PROTAC)could remarkably attenuate tau-induced autophagy impairment.Conclusions:Our findings reveal that AD-like tau accumulation inhibits autophagosome formation and induces autophagy deficits by activating the TIA1/amino acid/mTORC1 pathway,and thus this work reveals new insight into tau-associated neurodegeneration and provides evidence supporting the use of new therapeutic targets for AD treat-ment and that of related tauopathies.

The Lyman-alpha Solar Telescope(LST) for the ASO-S mission——Ⅱ. design of LST

As one of the three payloads for the Advanced Space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SDI)and a full-disk White-light Solar Telescope(WST).When working in-orbit,LST will simultaneously perform high-resolution imaging observations of all regions from the solar disk to the inner corona up to 2.5 R⊙(R⊙stands for the mean solar radius)with a spatial resolution of 4.8′′and 1.2′′for coronal and disk observations,respectively,and a temporal resolution of 30–120 s and 1–120 s for coronal and disk observations,respectively.The maximum exposure time can be up to20 s due to precise pointing and image stabilization function.Among the three telescopes of LST,SCI is a dual-waveband coronagraph simultaneously and independently observing the inner corona in the HI Lyα(121.6±10 nm)line and white light(WL)(700±40 nm)wavebands by using a narrowband Lyαbeam splitter and has a field of view(FOV)from 1.1 to 2.5 R⊙.The stray-light suppression level can attain<10^-6 B⊙(B⊙is the mean brightness of the solar disk)at 1.1 R⊙and≤5×10^-8 B⊙at 2.5 R⊙.SDI and WST are solar disk imagers working in the Lyαline and 360.0 nm wavebands,respectively,which adopt an off-axis two-mirror reflective structure with an FOV up to 1.2 R⊙,covering the inner coronal edge area and relating to coronal imaging.We present the up-to-date design for the LST payload.

Development and calibration of the Moon-based EUV camera for Chang'e-3

The process of development and calibration for the first Moon-based ex- treme ultraviolet （EUV） camera to observe Earth＇s plasmasphere is introduced and the design, test and calibration results are presented. The EUV camera is composed of a multilayer film mirror, a thin film filter, a photon-counting imaging detector, a mech- anism that can adjust the direction in two dimensions, a protective cover, an electronic unit and a thermal control unit. The center wavelength of the EUV camera is 30.2 nm with a bandwidth of 4.6nm. The field of view is 14.7° with an angular resolution of 0.08°, and the sensitivity of the camera is 0.11 count s-1 Rayleigh-1. The geomet- ric calibration, the absolute photometric calibration and the relative photometric cal- ibration are carried out under different temperatures before launch to obtain a matrix that can correct geometric distortion and a matrix for relative photometric correction, which are used for in-orbit correction of the images to ensure their accuracy.

PTC: Full and Drift Particle Orbit Tracing Code for α Particles in Tokamak Plasmas

Fusion born α particle confinement is one of the most important issues in burning plasmas,such as ITER and CFETR.However,it is extremely complex due to the nonequilibrium characteristics,and multiple temporal and spatial scales coupling with background plasma.A numerical code using particle orbit tracing method(PTC)has been developed to study energetic particle confinement in tokamak plasmas.Both full orbit and drift orbit solvers are implemented to analyze the Larmor radius effects on α particle confinement.The elastic collisions between alpha particles and thermal plasma are calculated by a Monte Carlo method.A triangle mesh in poloidal section is generated for electromagnetic fields expression.Benchmark between PTC and ORBIT has been accomplished for verification.For CFETR burning plasmas,PTC code is used for α particle source and slowing down process calculation in 2D equilibrium.In future work,3D field like toroidal field ripples,Alfven and magnetohydrodynamics instabilities perturbation inducing α particle transport will be analyzed.

Research progress of renal interstitial fibrosis

Renal interstitial fibrosis （RIF） is a common pathological process of chronic kidney disease that progresses toend-stage renal failure. The degree of RIF is closely related to renal function. The study of the pathogenesis of renalinterstitial fibrosis, exploration of effective prevention measures to delay the progress of end stage renal disease andprolong the life of patients is significant. The pathology of RIF has complicated extracellular and intercellularmechanisms, involving many cells and cytokines, resulting in an incomplete mechanistic understanding of thedisease. Finding effective herbs or herbal extracts for prevention and treatment of RIF is crucial because currentmedical approaches do not reliably slow or reverse RIF. The research progress of RIF in recent years issummarized as follows.

Wide-field auroral imager onboard the Fengyun satellite

The newly launched Fengyun-3D(FY-3D)satellite carried a wide-field auroral imager(WAI)that was developed by Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences(CIOMP),which will provide a large field of view(FOV),high spatial resolution,and broadband ultraviolet images of the aurora and the ionosphere by imaging the N2 LBH bands of emissions.The WAI consists of two identical cameras,each with an FOV of 68°in the along-track direction and 10°in the cross-track direction.The two cameras are tilted relative to each other to cover a fan-shaped field of size 130°×10°.Each camera consists of an unobstructed four-mirror anastigmatic optical system,a BaF2 filter,and a photon-counting imaging detector.The spatial resolution of WAI is ~10 km at the nadir point at a reference height of 110 km above the Earth’s surface.The sensitivity is>0.01 counts s^(−1) Rayleigh^(−1) pixel^(−1)(140-180 nm)for both cameras,which is sufficient for mapping the boundaries and the fine structures of the auroral oval during storms/substorms.Based on the tests and calibrations that were conducted prior to launch,the data processing algorithm includes photon signal decoding,geometric distortion correction,photometric correction,flatfield correction,line-of-sight projection and correction,and normalization between the two cameras.Preliminarily processed images are compared with DMSP SSUSI images.The agreement between the images that were captured by two instruments demonstrates that the WAI and the data processing algorithm operate normally and can provide high-quality scientific data for future studies on auroral dynamics.

Catalytic transfer hydrogenation of biomass-derived furfural to furfuryl alcohol with formic acid as hydrogen donor over CuCs-MCM catalyst

Catalytic transfer hydroge nation(CTH)of furfural(FF)to furfu ryl alcohol(FFA)has received great intere st in recent years.He rein,Cu-Cs bimetallic supported catalyst,CuCs(2)-MCM,was developed for the CTH of FF to FFA using formic as hydrogen donor.CuCs(2)-MCM achieved a 99.6%FFA yield at an optimized reaction conditions of 170℃,1 h.Cu species in CuCs(2)-MCM had dual functions in catalytically decomposing formic acid to generate hydrogen and hydrogenating FF to FFA.The doping of Cs made the size of Cu particles smaller and improved the dispersion of the Cu active sites.Impo rtantly,the Cs species played a favorable role in enhancing the hydrogenation activity as a promoter by adjusting the surface acidity of Cu species to an appropriate level.Correlation analysis showed that surface acidity is the primary factor to affect the catalytic activity of CuCs(2)-MCM.

Effects of the geometrical parameters of the injection nozzle on ethylene-air continuous rotating detonation

Compared with traditional isobaric combustion,continuous rotating detonation(CRD)has been theoretically proved to be a more efficient combustion mode with higher thermal cycle efficiency.However,the realization and stable operating of liquid kerosene detonation is still a challenge.As a major component of kerosene pyrolysis products after regenerative cooling,ethylene is a transitional hydrocarbon fuel from kerosene to hydrogen and it is worth studying.In this paper,a series of 2 D numerical simulations are conducted to investigate the effects of the injection nozzle on the ethylene-air CRD.Three geometrical parameters of the nozzle are thoroughly tested including the distance between two neighboring nozzle centers,the nozzle exit width,and the slant angle of the nozzle.The results show that an ethylene-air detonation wave is realized and it propagates stably.A small distance between two neighboring nozzle centers is conducive to improving the strength of the CRD wave and leads to greater feedback pressure into the plenum.As the nozzle exit width increases,the strength of the CRD wave and the feedback pressure into the plenum both increase.The CRD wave propagation velocity is greatly improved and the feedback pressure into the plenum is significantly reduced when the slant angle of the nozzle is positive.By contrast,a sizeable reduction in velocity is found when the angle is negative.The co-rotating two-wave propagation mode is observed when the angle is 30°,and the highest CRD propagation velocity and the lowest feedback pressure are both obtained when the angle is 60°.

Numerical study on ethylene-air continuous rotating detonation in annular combustors with different widths

To investigate the impact of combustor width on continuous rotating detonation(CRD)fueled by ethylene and air,a series of 3 D simulations are conducted by changing the inner cylinder radius of an annular combustor while retaining the same outer cylinder radius.The results show that the CRD wave propagates more steadily and faster as the combustor width increases.The high-temperature zone at the backward-facing step preheats the propellants and contributes to the steady propagation of the CRD wave in 25-and 30-mm wide combustors.The highest and the lowest velocities are obtained in the30-and 15-mm wide combustors at,respectively,1880.27 and 1681.01 m/s.On the other hand,the average thrust decreases as the combustor width increases.The highest thrust is obtained in the 15-mm wide combustor while the lowest is in the 30-mm wide combustor,at 758.06 and 525.93 N,respectively.Nevertheless,the thrust is much more stable in the 25-and 30-mm wide combustors than in the 15-and 20-mm wide combustors.

Solar X-ray and EUV imager on board the FY-3E satellite

The solar X-ray and Extreme Ultraviolet Imager(X-EUVI),developed by the Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences(CIOMP),is the first space-based solar X-ray and Extreme ultraviolet(EUV)imager of China loaded on the Fengyun-3E(FY-3E)satellite supported by the China Meteorological Administration(CMA)for solar observation.Since started work on July 11,2021,X-EUVI has obtained many solar images.The instrument employs an innovative dual-band design to monitor a much larger temperature range on the Sun,which covers 0.6-8.0 nm in the X-ray region with six channels and 19.5 nm in the EUV region.X-EUVI has a field of view of 42′,an angular resolution of 2.5″per pixel in the EUV band and an angular resolution of 4.1″per pixel in the X-ray band.The instrument also includes an X-ray and EUV irradiance sensor(X-EUVS)with the same bands as its imaging optics,which measures the solar irradiance and regularly calibrates the solar images.The radiometric calibration of X-EUVS on the ground has been completed,with a calibration accuracy of 12%.X-EUVI is loaded on the FY-3E satellite and rotates relative to the Sun at a uniform rate.Flat-field calibration is conducted by utilizing successive rotation solar images.The agreement between preliminarily processed X-EUVI images and SDO/AIA and Hinode/XRT images indicates that X-EUVI and the data processing algorithm operate properly and that the data from X-EUVI can be applied to the space weather forecast system of CMA and scientific investigations on solar activity.

Erratum to: Effects of the geometrical parameters of the injection nozzle on ethylene-air continuous rotating detonation

The original version of this article unfortunately contained a mistake.