The Tibetan Plateau(TP)is the youngest orogenic belt resulting from a continental collision on the Earth.It is a natural laboratory for studying continental dynamics,such as continental convergence,plate subduction,an...The Tibetan Plateau(TP)is the youngest orogenic belt resulting from a continental collision on the Earth.It is a natural laboratory for studying continental dynamics,such as continental convergence,plate subduction,and plateau uplift.Investigating the deep structure of the TP has always been a popular issue in geological research.The Moho is the boundary between the crust and the mantle and therefore plays a crucial role in the Earth’s structure.Parameters such as depth and lateral variation,as well as the fine structure of the crust-mantle interface,reveal the lithospheric dynamics in the TP.Two methods are generally employed to study the Moho surface:seismic detection and gravity inversion.Seismic detection has the characteristic of high precision,but it is limited to a few cross-sectional lines and is quite costly.It is not suitable for and cannot be carried out over a large area of the TP.The Moho depth over a large area can be obtained through gravity inversion,but this method is affected by the nature of gravity data,and the accuracy of the inversion method is lower than that of seismic detection.In this work,a high-precision gravity field model was selected.The Parker-Oldenburg interface inversion method was used,within the constraints of seismic observations,and the Bott iteration method was introduced to enhance the inversion efficiency.The Moho depth in the TP was obtained with high precision,consistent with the seismic detection results.The research results showed that the shape of the Moho in the TP is complex and the variation range is large,reaching 60−80 km.In contrast with the adjacent area,a clear zone of sharp variation appears at the edge of the plateau.In the interior of the TP,the buried depth of the Moho is characterized by two depressions and two uplifts.To the south of the Yarlung Zangbo River,the Moho inclines to the north,and to the north,the Moho depresses downward,which was interpreted as the Indian plate subducting to the north below Tibet.The Moho depression on the north side of the Qiangtang block,reaching 72 km deep,may be a result of the southward subduction of the lithosphere.The Moho uplift of the Qiangtang block has the same strike as the Bangong−Nujiang suture zone,which may indicate that the area is compensated by a low-density and low-velocity mantle.展开更多
Through vehicle-to-vehicle(V2V)communication,autonomizing a vehicle platoon can significantly reduce the distance between vehicles,thereby reducing air resistance and improving road traffic efficiency.The gradual matu...Through vehicle-to-vehicle(V2V)communication,autonomizing a vehicle platoon can significantly reduce the distance between vehicles,thereby reducing air resistance and improving road traffic efficiency.The gradual maturation of platoon control technology is enabling vehicle platoons to achieve basic driving functions,thereby permitting large-scale vehicle platoon scheduling and planning,which is essential for industrialized platoon applications and generates significant economic benefits.Scheduling and planning are required in many aspects of vehicle platoon operation;here,we outline the advantages and challenges of a number of the most important applications,including platoon formation scheduling,lane-change planning,passing traffic light scheduling,and vehicle resource allocation.This paper’s primary objective is to integrate current independent platoon scheduling and planning techniques into an integrated architecture to meet the demands of large-scale platoon applications.To this end,we first summarize the general techniques of vehicle platoon scheduling and planning,then list the primary scenarios for scheduling and planning technique application,and finally discuss current challenges and future development trends in platoon scheduling and planning.We hope that this paper can encourage related platoon researchers to conduct more systematic research and integrate multiple platoon scheduling and planning technologies and applications.展开更多
Nano-TATB was developed in microchannels by physical method and chemical method,respectively.The effects of total flow rate,number of microreactor plates,solvent/non-solvent ratio and temperature on the particle size ...Nano-TATB was developed in microchannels by physical method and chemical method,respectively.The effects of total flow rate,number of microreactor plates,solvent/non-solvent ratio and temperature on the particle size of TATB in the physical method were studied.Prepared TATB were characterized by Nano Sizer,Scanning Electron Microscopy,Specific surface aperture analyzer,X-ray diffraction,Fourier transform infrared spectroscopy and Differential Scanning Calorimetry.The results show that the TATB obtained by physical method and chemical method are spherical,with average particle size of 130.66 nm and 108.51 nm,respectively.Specific surface areas of TATB obtained by physical and chemical methods are 21.37 m^(2)/g and 21.91 m^(2)/g,respectively.Compared with the specific surface area of micro-TATB(0.0808 m^(2)/g),the specific surface area of nano-TATB is significantly increased.DSC test results show that the smaller the particle size of TATB,the lower the thermal decomposition temperature.In addition,by simulating the mixing state of fluid in microchannels and combining with the classical nucleation theory,the mechanism of preparing nano-TATB by microchannels was proposed.展开更多
It is difficult for solanum crops to grow continuously during winter in severe cold regions. Thus, a soil heating system for facility agriculture based on solar concentration technology was proposed, and a novel compo...It is difficult for solanum crops to grow continuously during winter in severe cold regions. Thus, a soil heating system for facility agriculture based on solar concentration technology was proposed, and a novel compound parabolic concentration photothermal and photoelectricity device(CTPV) equipped in the system was designed to address this problem. In accordance with the structure of the device, LightTools optical software was selected to analyze the variation trend of the light escape rate of the device with the diff erent incident angles. On the basis of the calculation results, an experimental test system was used to investigate the relationship of the air temperature of the inlet and the outlet, total output power of the solar cells, and photothermal and photoelectricity efficiency of the device with the operation time during a sunny day. Research results reveal that the light escape rate of the device is 5.36% at an incidence angle of 12°. At a velocity of 1.5 m/s, the maximum air temperature of the outlet can reach 55.6 ℃, and the total output power of the solar cells is 474.4 W. The variation of the total power of the solar cells is consistent with the simulation results. The maximum instantaneous heat collection and the maximum photothermal and photoelectricity efficiency of the device are 306 W and 60.4%, respectively, and the average efficiency is 44.9%. This study can serve as a reference for compound parabolic concentration technology applied for soil heating in facility agricultural soil heating systems.展开更多
The aim of this study was to find a way to efficiently separate neuronal cells from the cerebral cortex of adult rats,providing a reference method for rapid acquisition of neuronal cells from the adult rat brain.Fifte...The aim of this study was to find a way to efficiently separate neuronal cells from the cerebral cortex of adult rats,providing a reference method for rapid acquisition of neuronal cells from the adult rat brain.Fifteen SD rats were randomly divided into three groups,with five SD rats in each group.Then,neuron cells were isolated from the adult rat cerebral cortex by the grinding method,the trypsin method,and the collagenase II method,respectively.The expression of anti-NeuN in the neurons of each group was analyzed by flow cytometry.The acquisition rates and morphology of neurons of each group were observed by immunofluorescence staining.The grinding or collagenase II method is more suitable for rapid acquisition of neuronal cells from an adult rat’s cerebral cortex.The number of neuron cells obtained by the trypsin method were very few,so it is not convenient for later experiments.展开更多
Due to the weakness in mechanical properties of chlorite schist and the high in situ stress in Jinping II hydropower station, the rock mass surrounding the diversion tunnels located in chlorite schist was observed wit...Due to the weakness in mechanical properties of chlorite schist and the high in situ stress in Jinping II hydropower station, the rock mass surrounding the diversion tunnels located in chlorite schist was observed with extremely large deformations. This may significantly increase the risk of tunnel instability during excavation. In order to assess the stability of the diversion tunnels laboratory tests were carried out in association with the petrophysical properties, mechanical behaviors and waterlweakening properties of chlorite schist. The continuous deformation of surrounding rock mass, the destruction of the support structure and a large-scale collapse induced by the weak chlorite schist and high in situ stress were analyzed. The distributions of compressive deformation in the excavation zone with large deformations were also studied. In this regard, two reinforcement schemes for the excavation of diversion tunnel bottom section were proposed accordingly. This study could offer theoretical basis for deed tunnel construction in similar geological condition~展开更多
Generation of noise-like rectangular pulse was investigated systematically in an Er–Yb co-doped fiber laser based on an intra-cavity coupler with different coupling ratios.When the coupling ratio was 5/95,stable mode...Generation of noise-like rectangular pulse was investigated systematically in an Er–Yb co-doped fiber laser based on an intra-cavity coupler with different coupling ratios.When the coupling ratio was 5/95,stable mode-locked pulses could be obtained with the pulse packet duration tunable from 4.86 ns to 80 ns.The repetition frequency was 1.186 MHz with the output spectrum centered at 1.6μm.The average output power and single pulse energy reached a record 1.43 W and1.21μJ,respectively.Pulse characteristics under different coupling ratios(5/95,10/90,20/80,30/70,40/60)were also presented and discussed.展开更多
Populus(poplars)and Salix(willows)are sister genera in the Salicaceae family that arise from a common tetraploid ancestor.The karyotypes of these two lineages are distinguished by two major interchromosomal and some m...Populus(poplars)and Salix(willows)are sister genera in the Salicaceae family that arise from a common tetraploid ancestor.The karyotypes of these two lineages are distinguished by two major interchromosomal and some minor intrachromosomal rearrangements,but which one is evolutionarily more primitive remains debatable.In this study,we compare the selection pressure acting on the paralogous genes resulting from salicoid duplication(PGRS)within and between the genomes of the two lineages.Purifying selection was determined to act more strongly on the PGRS in willow than on those in poplar,which would cause a faster loss of paralogous duplicates in willow.Therefore,Salix species are supposed to evolve faster than Populus species,which is consistent with the observation that the former are taxonomically and morphologically more diverse than the latter.In these two lineages,different autosomes were found to have been evolving into sex chromosomes.Examining theωratio and the PGRS in the sex determination regions in willow and poplar revealed higher convergent selection pressure and a faster loss of PGRS in the sex determination regions of both lineages.At the chromosome level,the sex chromosome in poplar is characterized by the lowest gene density among all chromosome members,while this feature is not observed on the sex chromosome in willow,suggesting that Populus species may inherit the more incipient sex chromosome from their progenitor.Taken together,Salix is supposed to be the nascent lineage arising from the additional round of genome reorganization that distinguishes the karyotypes of the two sister genera.In this study,assessment ofωratios also detected a list of paralogous genes under unusual selection pressure,which could have special consequences for the adaptive evolution of Salicaceae species.In conclusion,the results of this study provide unique information for better understanding the genetic mechanism accelerating the divergence of these two closely related lineages.展开更多
This paper uses FLUENT software building the three-dimensional unsteady state model of ground source heat pump single U and double U underground pipe to study on heat exchange of underground pipe system in the conditi...This paper uses FLUENT software building the three-dimensional unsteady state model of ground source heat pump single U and double U underground pipe to study on heat exchange of underground pipe system in the condition of unsteady state long-term continuous running, analyzes the change of soil temperature filed around underground pipe and performance of underground pipe heat exchange between single U and double U pipe system. The results show that double U pipe system is better than single U system, which can improve unit depth heat exchange efficiency, reduce the number of wells and reduce the initial investment.展开更多
We demonstrate efficient supercontinuum generation extending into mid-infrared spectral range by pumping a twomode As2S3 fiber in the normal dispersion regime. The As2S3 fiber is fusion spliced to the pigtail of a nea...We demonstrate efficient supercontinuum generation extending into mid-infrared spectral range by pumping a twomode As2S3 fiber in the normal dispersion regime. The As2S3 fiber is fusion spliced to the pigtail of a near-infrared supercontinuum pump source with ultra-low splicing loss of 0.125 dB, which enables a monolithic all-fiber mid-infrared supercontinuum source. By two-mode excitation and mixed-mode cascaded stimulated Raman scattering, a supercontinuum spanning from 1.8 μm to 4.2 μm is obtained. Over 70% of the supercontinuum power is converted to wavelengths beyond2.4 μm. This is the first experimental report with respect to the multimode mid-infrared supercontinuum generation in a step-index two-mode chalcogenide fiber.展开更多
Fiber-based mid-infrared(MIR)supercontinuum(SC)sources benefit from their spectral brightness and spatial coherence that are needed for many applications,such as spectroscopy and metrology.In this paper,an SC spanning...Fiber-based mid-infrared(MIR)supercontinuum(SC)sources benefit from their spectral brightness and spatial coherence that are needed for many applications,such as spectroscopy and metrology.In this paper,an SC spanning from 2μm to 6μm is demonstrated in cascaded ZrF4-BaF2-LaF3-AlF3-NaF(ZBLAN)and As2Se3 step-index fibers.The pump source is a ZBLAN fiber-based MIR SC laser with abundant high-peak-power soliton pulses between 3000 nm and 4200 nm.By concatenating the ZBLAN fiber and the As2 Se3 fiber,efficient cascading red-shifts are obtained in the normal dispersion region of the As2 Se3 fiber.The spectral behavior of cascaded SC generation shows that the long-wavelength proportion of MIR SC generated in the ZBLAN fiber plays a critical role for further spectral extension in the As2 Se3 fiber.展开更多
OBJECTIVE: To thoroughly investigate clinical characteristics of progressive supranuclear palsy (PSP) in a Chinese population. METHODS: Computer-based online searches through China National Knowledge Infrastructur...OBJECTIVE: To thoroughly investigate clinical characteristics of progressive supranuclear palsy (PSP) in a Chinese population. METHODS: Computer-based online searches through China National Knowledge Infrastructure and Weipu Periodical Database were performed to collect case reports of PSP published between 1980 and 2009. Clinical characteristics were analyzed. RESULTS: A total of 58 studies comprising 105 patients (76 males and 29 females) were included. All cases were sporadic and free of family history. The mean age at onset was 60.6 _+ 9.1 years, and the mean course from onset of symptoms to diagnosis was 3.4 + 2.4 years. The male-to-female ratio was approximately 3: 1. Onset was characterized by akinetic-dgid features and accounted for 34.3% of all cases, followed by early postural instability (25.5%), pseudobulbar palsy (9.8%), cognitive impairment (9.8%), and vertical supranuclear ophthalmoplegia (7.8%). With disease progression, vertical supranuclear ophthalmoplegia was reported in 95.1% of cases, followed by akinetic-rigid features (83.3%), pseudobulbar palsy (82.4%), axial dystonia (75.5%), cognitive impairment (72.5%), and early postural instability (69.6%). A total of 70.5% of patients exhibited abnormal electroencephalograms, and 21.4% exhibited mild abnormalities in cerebrospinal fluid. Brain CT scanning results of 37 patients showed 37.8% with midbrain and concurrent cerebral hemisphere atrophy, and 5.4% and 24.3% with midbrain and cerebral hemisphere atrophy, respectively. Brain MRI scanning results of 55 patients revealed a total of 16.4% patients with midbrain atrophy, 23.6% with midbrain and concurrent cerebral hemisphere atrophy, 32.7% with cerebral hemisphere atrophy, and 11% with brainstem atrophy. The percentage of midbrain atrophy revealed by MRI was greater than by CT. All 11 patients subjected to Mini-Mental State Examination scored 〈 23. A total of 10 patients underwent brain electrophysiological examination, and 80% presented with abnormalities of cerebral-evoked potential. A total of 33.3% patients presented with neurogenic damage of anal sphincter electromyography. Nine cases were neuropathologically diagnosed, and all displayed tau-positive argyrophilic globous neurofibrillary tangles, tuft-shaped astrocytes, and coiled bodies. Gene diagnosis was not performed. A total of 40 patients were misdiagnosed, including 23 (58%) as Parkinson's disease and seven (18%) as Parkinsonism; 44 patients were treated by madopar, artane, or amantadine, and only seven (16%) improved in movement. No patients exhibited improved eye movement. Of 4 patients treated with madopar and dopa agonists, 2 improved in movement. In addition, movement improved in 3 patients treated with madopar and monoamine oxidase B. CONCLUSION: PSP is a sporadic disease that often strikes middle or elderly individuals. There are no significant differences in age of onset between male and female patients, although disease progression is more rapid in female patients, likely because the time from symptom onset to disease diagnosis in females is less than in male. Akinetic-rigid features and early postural instability are the most common symptoms of onset. With disease progression, the incidence of vertical supranuclear ophthalmoplegia and akinetic-rigid features increases. MRI is a common, sensitive, and noninvasive supplemental test. However, PSP is frequently misdiagnosed as Parkinson's disease or Parkinsonism during the early stage, and anti-Parkinson treatments remain ineffective.展开更多
Event-related potential (ERP) studies of cognitive function in Parkinson's disease (PD) have focused on P300 and N270. However, little is known regarding face recognition ERP in PD. The present study assessed cog...Event-related potential (ERP) studies of cognitive function in Parkinson's disease (PD) have focused on P300 and N270. However, little is known regarding face recognition ERP in PD. The present study assessed cognitive function in PD patients using neuropsychological scales and analyzed N170 of visuospatial function impairment (VFI) in PD. Results showed that Montreal cognitive assessment can be used for assessing cognitive impairment when visuospatial functioning is changed during the early stage of PD. Face recognition has clinical significance for detecting changes in visuospatial functioning. However, N170 is not sensitive for detection of VFI in PD, which implies that VFI does not appear in the stage of structure coding in face recognition. In addition, VFI affects face recognition.展开更多
BACKGROUND Tumor-to-tumor metastasis(TTM)is an uncommon condition.Only a few cases of renal cell carcinoma(RCC)as donor tumor of TTM have been reported in literature,and none of these studies have described RCC metast...BACKGROUND Tumor-to-tumor metastasis(TTM)is an uncommon condition.Only a few cases of renal cell carcinoma(RCC)as donor tumor of TTM have been reported in literature,and none of these studies have described RCC metastasizing to synchronous pheochromocytoma(PCC).CASE SUMMARY The patient was a 54-year-old woman who presented with recurrent dull abdominal pain for six months,which was further aggravated for one more month.Enhanced computed tomography revealed a tumor mass in the right kidney and another mass in the left retroperitoneum/adrenal gland.Histopathology and immunochemistry of resected specimens confirmed the diagnosis of clear cell renal cell carcinoma(CCRCC)of the right kidney,and the left retroperitoneum revealed a typical PCC with CCRCC metastasis.Whole exome sequencing revealed the presence of a c.529A>T somatic mutation of the Von Hippel Lindau(VHL)gene in the metastasized CCRCC,which was also present in the primary right kidney CCRCC,as confirmed by Sanger sequencing.No VHL mutation was detected in the PCC or in normal right kidney tissue.Fluorescence in situ hybridization revealed loss of chromosome 3p in both the primary right kidney CCRCC and CCRCC metastasized to PCC in the left kidney.CONCLUSION This is the first case showing metastasis of CCRCC to PCC,thus leading to tumorto-tumor metastasis.展开更多
An all-fiber dumbbell-shaped dual-amplifier mode-locked Er-doped laser that can function in dissipative soliton resonance(DSR)regime is demonstrated.A nonlinear optical loop mirror(NOLM)and a nonlinear amplifying loop...An all-fiber dumbbell-shaped dual-amplifier mode-locked Er-doped laser that can function in dissipative soliton resonance(DSR)regime is demonstrated.A nonlinear optical loop mirror(NOLM)and a nonlinear amplifying loop mirror(NALM)are employed to initiate the mode-locking pulses.Unlike conventional single-amplifier structure,the output peak power of which remains unchanged when pump power is varied,the proposed structure allows its output peak power to be tuned by changing the pump power of the two amplifiers while the pulse duration is directly determined by the amplifier of nonlinear amplifying loop mirror.The entire distribution maps of peak power and pulse duration clearly demonstrate that the two amplifiers are related to each other,and they supply directly a guideline for designing tunable peak power DSR fiber laser.Pulse width can change from 800 ps to 2.6 ns and peak power varies from 13 W to 27 W.To the best of our knowledge,the peak power tunable DSR pulse is observed for the first time in dumbbell-shaped Er-doped all-fiber mode-locked lasers.展开更多
[Objectives]To make pharmacognostic identification of Euphorbia maculata L.and its related species.[Methods]The classical pharmacognostic identification method was adopted.[Results]The four main medicinal materials ar...[Objectives]To make pharmacognostic identification of Euphorbia maculata L.and its related species.[Methods]The classical pharmacognostic identification method was adopted.[Results]The four main medicinal materials are very similar,the fluff can be seen in E.maculata and Euphorbia thymifolia L.,but not in Euphorbia prostrata Ait.and Euphorbia taihsiensis(Chaw et Koutnik)Oudejians;the tissue structure is basically the same;except for E.taihsiensis without non-glandular hairs,the powder has secretory cells,laticifers,cells,calcium oxalate crystals,fibers,vessels,and seed coat fragments.Through ultrasonic extraction with 80%ethanol,extraction with isobutanol,extending with chloroform∶ethyl acetate∶formic acid(5∶3∶0.3),developing color with 3%aluminum trichloride ethanol solution,under ultraviolet light(365 nm),the fluorescent spots of the same color appeared on the corresponding position of the chromatogram of the reference substance(quercetin,kaempferol).[Conclusions]It is not easy to distinguish the four medicinal materials by character identification and microscopic identification,while the thin-layer chromatography(TLC)is more reliable.展开更多
ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly understood.Our study reveals that ACBP4 serves as a positive regulator of the...ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly understood.Our study reveals that ACBP4 serves as a positive regulator of the plant hypoxia response by interacting with WRKY70,influencing its nucleocytoplasmic shuttling in Arabidopsis thaliana.Furthermore,we demonstrate the direct binding of WRKY70 to the ACBP4 promoter,resulting in its upregulation and suggesting a positive feedback loop.Additionally,we pinpointed a phosphorylation site at Ser638 of ACBP4,which enhances submergence tolerance,potentially by facilitating WRKY70's nuclear shuttling.Surprisingly,a natural variation in this phosphorylation site of ACBP4 allowed A.thaliana to adapt to humid conditions during its historical demographic expansion.We further observed that both phosphorylated ACBP4 and oleoyl-Co A can impede the interaction between ACBP4 and WRKY70,thus promoting WRKY70's nuclear translocation.Finally,we found that the overexpression of orthologous Bna C5.ACBP4and Bna A7.WRKY70 in Brassica napus increases submergence tolerance,indicating their functional similarity across genera.In summary,our research not only sheds light on the functional significance of the ACBP4 gene in hypoxia response,but also underscores its potential utility in breeding flooding-tolerant oilseed rape varieties.展开更多
Obesity-induced chronic inflammation exacerbates multiple types of tissue/organ deterioration and stem cell dysfunction;however,the effects on skeletal tissue and the underlying mechanisms are still unclear.Here,we sh...Obesity-induced chronic inflammation exacerbates multiple types of tissue/organ deterioration and stem cell dysfunction;however,the effects on skeletal tissue and the underlying mechanisms are still unclear.Here,we show that obesity triggers changes in the microRNA profile of macrophage-secreted extracellular vesicles,leading to a switch in skeletal stem/progenitor cell(SSPC)differentiation between osteoblasts and adipocytes and bone deterioration.Bone marrow macrophage(BMM)-secreted extracellular vesicles(BMM-EVs)from obese mice induced bone deterioration(decreased bone volume,bone microstructural deterioration,and increased adipocyte numbers)when administered to lean mice.Conversely,BMM-EVs from lean mice rejuvenated bone deterioration in obese recipients.We further screened the differentially expressed microRNAs in obese BMM-EVs and found that among the candidates,miR-140(with the function of promoting adipogenesis)and miR-378a(with the function of enhancing osteogenesis)coordinately determine SSPC fate of osteogenic and adipogenic differentiation by targeting the Pparα-Abca1 axis.BMM miR-140 conditional knockout mice showed resistance to obesity-induced bone deterioration,while miR-140 overexpression in SSPCs led to low bone mass and marrow adiposity in lean mice.BMM miR-378a conditional depletion in mice led to obesity-like bone deterioration.More importantly,we used an SSPC-specific targeting aptamer to precisely deliver miR-378a-3p-overloaded BMM-EVs to SSPCs via an aptamer-engineered extracellular vesicle delivery system,and this approach rescued bone deterioration in obese mice.Thus,our study reveals the critical role of BMMs in mediating obesity-induced bone deterioration by transporting selective extracellular-vesicle microRNAs into SSPCs and controlling SSPC fate.展开更多
基金the National Natural Science Foundation of China(Grant No.42192535)the Open Fund of Wuhan,Gravitation and Solid Earth Tides,National Observation and Research Station(No.WHYWZ202204)+1 种基金the Strategic Pioneer Science and Technology Special Project of the Chinese Academy of Sciences(Grant No.XDB18010304)the National Natural Science Foundation of China(Grant No.41874096).
文摘The Tibetan Plateau(TP)is the youngest orogenic belt resulting from a continental collision on the Earth.It is a natural laboratory for studying continental dynamics,such as continental convergence,plate subduction,and plateau uplift.Investigating the deep structure of the TP has always been a popular issue in geological research.The Moho is the boundary between the crust and the mantle and therefore plays a crucial role in the Earth’s structure.Parameters such as depth and lateral variation,as well as the fine structure of the crust-mantle interface,reveal the lithospheric dynamics in the TP.Two methods are generally employed to study the Moho surface:seismic detection and gravity inversion.Seismic detection has the characteristic of high precision,but it is limited to a few cross-sectional lines and is quite costly.It is not suitable for and cannot be carried out over a large area of the TP.The Moho depth over a large area can be obtained through gravity inversion,but this method is affected by the nature of gravity data,and the accuracy of the inversion method is lower than that of seismic detection.In this work,a high-precision gravity field model was selected.The Parker-Oldenburg interface inversion method was used,within the constraints of seismic observations,and the Bott iteration method was introduced to enhance the inversion efficiency.The Moho depth in the TP was obtained with high precision,consistent with the seismic detection results.The research results showed that the shape of the Moho in the TP is complex and the variation range is large,reaching 60−80 km.In contrast with the adjacent area,a clear zone of sharp variation appears at the edge of the plateau.In the interior of the TP,the buried depth of the Moho is characterized by two depressions and two uplifts.To the south of the Yarlung Zangbo River,the Moho inclines to the north,and to the north,the Moho depresses downward,which was interpreted as the Indian plate subducting to the north below Tibet.The Moho depression on the north side of the Qiangtang block,reaching 72 km deep,may be a result of the southward subduction of the lithosphere.The Moho uplift of the Qiangtang block has the same strike as the Bangong−Nujiang suture zone,which may indicate that the area is compensated by a low-density and low-velocity mantle.
基金funded by the Shanghai Municipal Science and Technology Major Project(2018SHZDZX01)of Zhang Jiang Laboratory and Shanghai Center for Brain Science and Brain-Inspired TechnologyShanghai Rising Star Program(21QC1400900)Tongji–Westwell Autonomous Vehicle Joint Lab Project。
文摘Through vehicle-to-vehicle(V2V)communication,autonomizing a vehicle platoon can significantly reduce the distance between vehicles,thereby reducing air resistance and improving road traffic efficiency.The gradual maturation of platoon control technology is enabling vehicle platoons to achieve basic driving functions,thereby permitting large-scale vehicle platoon scheduling and planning,which is essential for industrialized platoon applications and generates significant economic benefits.Scheduling and planning are required in many aspects of vehicle platoon operation;here,we outline the advantages and challenges of a number of the most important applications,including platoon formation scheduling,lane-change planning,passing traffic light scheduling,and vehicle resource allocation.This paper’s primary objective is to integrate current independent platoon scheduling and planning techniques into an integrated architecture to meet the demands of large-scale platoon applications.To this end,we first summarize the general techniques of vehicle platoon scheduling and planning,then list the primary scenarios for scheduling and planning technique application,and finally discuss current challenges and future development trends in platoon scheduling and planning.We hope that this paper can encourage related platoon researchers to conduct more systematic research and integrate multiple platoon scheduling and planning technologies and applications.
基金National Natural Science Foundation of China(No.21875109)to provide fund for conducting experiments.
文摘Nano-TATB was developed in microchannels by physical method and chemical method,respectively.The effects of total flow rate,number of microreactor plates,solvent/non-solvent ratio and temperature on the particle size of TATB in the physical method were studied.Prepared TATB were characterized by Nano Sizer,Scanning Electron Microscopy,Specific surface aperture analyzer,X-ray diffraction,Fourier transform infrared spectroscopy and Differential Scanning Calorimetry.The results show that the TATB obtained by physical method and chemical method are spherical,with average particle size of 130.66 nm and 108.51 nm,respectively.Specific surface areas of TATB obtained by physical and chemical methods are 21.37 m^(2)/g and 21.91 m^(2)/g,respectively.Compared with the specific surface area of micro-TATB(0.0808 m^(2)/g),the specific surface area of nano-TATB is significantly increased.DSC test results show that the smaller the particle size of TATB,the lower the thermal decomposition temperature.In addition,by simulating the mixing state of fluid in microchannels and combining with the classical nucleation theory,the mechanism of preparing nano-TATB by microchannels was proposed.
基金the financial support for this research provided by the National Natural Science Foundation of China (No. 51966012) ProjectProgram for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region (No. NJYT-18-A12)+2 种基金Research Program of Science and Technology at Universities of Inner Mongolia Autonomous Region (No. NJZY17491)Major science and Technology Projects in Inner Mongolia (2018)Inner Mongolia Autonomous Region Graduate Research Innovation Project (No. S20201156Z)。
文摘It is difficult for solanum crops to grow continuously during winter in severe cold regions. Thus, a soil heating system for facility agriculture based on solar concentration technology was proposed, and a novel compound parabolic concentration photothermal and photoelectricity device(CTPV) equipped in the system was designed to address this problem. In accordance with the structure of the device, LightTools optical software was selected to analyze the variation trend of the light escape rate of the device with the diff erent incident angles. On the basis of the calculation results, an experimental test system was used to investigate the relationship of the air temperature of the inlet and the outlet, total output power of the solar cells, and photothermal and photoelectricity efficiency of the device with the operation time during a sunny day. Research results reveal that the light escape rate of the device is 5.36% at an incidence angle of 12°. At a velocity of 1.5 m/s, the maximum air temperature of the outlet can reach 55.6 ℃, and the total output power of the solar cells is 474.4 W. The variation of the total power of the solar cells is consistent with the simulation results. The maximum instantaneous heat collection and the maximum photothermal and photoelectricity efficiency of the device are 306 W and 60.4%, respectively, and the average efficiency is 44.9%. This study can serve as a reference for compound parabolic concentration technology applied for soil heating in facility agricultural soil heating systems.
基金the National Natural Science Foundation of China(No.81960129)Qinghai basic Research Plan Project(No.2019-ZJ-922)Middle-aged and Youth Foundation of Qinghai university affiliated hospital(No.2018-QYY-13).
文摘The aim of this study was to find a way to efficiently separate neuronal cells from the cerebral cortex of adult rats,providing a reference method for rapid acquisition of neuronal cells from the adult rat brain.Fifteen SD rats were randomly divided into three groups,with five SD rats in each group.Then,neuron cells were isolated from the adult rat cerebral cortex by the grinding method,the trypsin method,and the collagenase II method,respectively.The expression of anti-NeuN in the neurons of each group was analyzed by flow cytometry.The acquisition rates and morphology of neurons of each group were observed by immunofluorescence staining.The grinding or collagenase II method is more suitable for rapid acquisition of neuronal cells from an adult rat’s cerebral cortex.The number of neuron cells obtained by the trypsin method were very few,so it is not convenient for later experiments.
基金financial supports from the National Natural Science Foundation of China under Grant Nos.51009132,10972221,10672167 and 41172288the National Basic Research Program of China under Grant No. 2014CB046902
文摘Due to the weakness in mechanical properties of chlorite schist and the high in situ stress in Jinping II hydropower station, the rock mass surrounding the diversion tunnels located in chlorite schist was observed with extremely large deformations. This may significantly increase the risk of tunnel instability during excavation. In order to assess the stability of the diversion tunnels laboratory tests were carried out in association with the petrophysical properties, mechanical behaviors and waterlweakening properties of chlorite schist. The continuous deformation of surrounding rock mass, the destruction of the support structure and a large-scale collapse induced by the weak chlorite schist and high in situ stress were analyzed. The distributions of compressive deformation in the excavation zone with large deformations were also studied. In this regard, two reinforcement schemes for the excavation of diversion tunnel bottom section were proposed accordingly. This study could offer theoretical basis for deed tunnel construction in similar geological condition~
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61435009,61235008,and 61405254)
文摘Generation of noise-like rectangular pulse was investigated systematically in an Er–Yb co-doped fiber laser based on an intra-cavity coupler with different coupling ratios.When the coupling ratio was 5/95,stable mode-locked pulses could be obtained with the pulse packet duration tunable from 4.86 ns to 80 ns.The repetition frequency was 1.186 MHz with the output spectrum centered at 1.6μm.The average output power and single pulse energy reached a record 1.43 W and1.21μJ,respectively.Pulse characteristics under different coupling ratios(5/95,10/90,20/80,30/70,40/60)were also presented and discussed.
基金supported by the National Key Research and Development Plan of China(2016YFD0600101)the National Natural Science Foundation of China(31500533 and 31570662).
文摘Populus(poplars)and Salix(willows)are sister genera in the Salicaceae family that arise from a common tetraploid ancestor.The karyotypes of these two lineages are distinguished by two major interchromosomal and some minor intrachromosomal rearrangements,but which one is evolutionarily more primitive remains debatable.In this study,we compare the selection pressure acting on the paralogous genes resulting from salicoid duplication(PGRS)within and between the genomes of the two lineages.Purifying selection was determined to act more strongly on the PGRS in willow than on those in poplar,which would cause a faster loss of paralogous duplicates in willow.Therefore,Salix species are supposed to evolve faster than Populus species,which is consistent with the observation that the former are taxonomically and morphologically more diverse than the latter.In these two lineages,different autosomes were found to have been evolving into sex chromosomes.Examining theωratio and the PGRS in the sex determination regions in willow and poplar revealed higher convergent selection pressure and a faster loss of PGRS in the sex determination regions of both lineages.At the chromosome level,the sex chromosome in poplar is characterized by the lowest gene density among all chromosome members,while this feature is not observed on the sex chromosome in willow,suggesting that Populus species may inherit the more incipient sex chromosome from their progenitor.Taken together,Salix is supposed to be the nascent lineage arising from the additional round of genome reorganization that distinguishes the karyotypes of the two sister genera.In this study,assessment ofωratios also detected a list of paralogous genes under unusual selection pressure,which could have special consequences for the adaptive evolution of Salicaceae species.In conclusion,the results of this study provide unique information for better understanding the genetic mechanism accelerating the divergence of these two closely related lineages.
文摘This paper uses FLUENT software building the three-dimensional unsteady state model of ground source heat pump single U and double U underground pipe to study on heat exchange of underground pipe system in the condition of unsteady state long-term continuous running, analyzes the change of soil temperature filed around underground pipe and performance of underground pipe heat exchange between single U and double U pipe system. The results show that double U pipe system is better than single U system, which can improve unit depth heat exchange efficiency, reduce the number of wells and reduce the initial investment.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61435009,61235008,and 61405254)
文摘We demonstrate efficient supercontinuum generation extending into mid-infrared spectral range by pumping a twomode As2S3 fiber in the normal dispersion regime. The As2S3 fiber is fusion spliced to the pigtail of a near-infrared supercontinuum pump source with ultra-low splicing loss of 0.125 dB, which enables a monolithic all-fiber mid-infrared supercontinuum source. By two-mode excitation and mixed-mode cascaded stimulated Raman scattering, a supercontinuum spanning from 1.8 μm to 4.2 μm is obtained. Over 70% of the supercontinuum power is converted to wavelengths beyond2.4 μm. This is the first experimental report with respect to the multimode mid-infrared supercontinuum generation in a step-index two-mode chalcogenide fiber.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61435009,61235008,and 61405254)the Fund from China Scholarship Council(Grant No.201803170210)Hunan Provincial Innovation Foundation for Postgraduate(Grant No.CX2018B008)
文摘Fiber-based mid-infrared(MIR)supercontinuum(SC)sources benefit from their spectral brightness and spatial coherence that are needed for many applications,such as spectroscopy and metrology.In this paper,an SC spanning from 2μm to 6μm is demonstrated in cascaded ZrF4-BaF2-LaF3-AlF3-NaF(ZBLAN)and As2Se3 step-index fibers.The pump source is a ZBLAN fiber-based MIR SC laser with abundant high-peak-power soliton pulses between 3000 nm and 4200 nm.By concatenating the ZBLAN fiber and the As2 Se3 fiber,efficient cascading red-shifts are obtained in the normal dispersion region of the As2 Se3 fiber.The spectral behavior of cascaded SC generation shows that the long-wavelength proportion of MIR SC generated in the ZBLAN fiber plays a critical role for further spectral extension in the As2 Se3 fiber.
文摘OBJECTIVE: To thoroughly investigate clinical characteristics of progressive supranuclear palsy (PSP) in a Chinese population. METHODS: Computer-based online searches through China National Knowledge Infrastructure and Weipu Periodical Database were performed to collect case reports of PSP published between 1980 and 2009. Clinical characteristics were analyzed. RESULTS: A total of 58 studies comprising 105 patients (76 males and 29 females) were included. All cases were sporadic and free of family history. The mean age at onset was 60.6 _+ 9.1 years, and the mean course from onset of symptoms to diagnosis was 3.4 + 2.4 years. The male-to-female ratio was approximately 3: 1. Onset was characterized by akinetic-dgid features and accounted for 34.3% of all cases, followed by early postural instability (25.5%), pseudobulbar palsy (9.8%), cognitive impairment (9.8%), and vertical supranuclear ophthalmoplegia (7.8%). With disease progression, vertical supranuclear ophthalmoplegia was reported in 95.1% of cases, followed by akinetic-rigid features (83.3%), pseudobulbar palsy (82.4%), axial dystonia (75.5%), cognitive impairment (72.5%), and early postural instability (69.6%). A total of 70.5% of patients exhibited abnormal electroencephalograms, and 21.4% exhibited mild abnormalities in cerebrospinal fluid. Brain CT scanning results of 37 patients showed 37.8% with midbrain and concurrent cerebral hemisphere atrophy, and 5.4% and 24.3% with midbrain and cerebral hemisphere atrophy, respectively. Brain MRI scanning results of 55 patients revealed a total of 16.4% patients with midbrain atrophy, 23.6% with midbrain and concurrent cerebral hemisphere atrophy, 32.7% with cerebral hemisphere atrophy, and 11% with brainstem atrophy. The percentage of midbrain atrophy revealed by MRI was greater than by CT. All 11 patients subjected to Mini-Mental State Examination scored 〈 23. A total of 10 patients underwent brain electrophysiological examination, and 80% presented with abnormalities of cerebral-evoked potential. A total of 33.3% patients presented with neurogenic damage of anal sphincter electromyography. Nine cases were neuropathologically diagnosed, and all displayed tau-positive argyrophilic globous neurofibrillary tangles, tuft-shaped astrocytes, and coiled bodies. Gene diagnosis was not performed. A total of 40 patients were misdiagnosed, including 23 (58%) as Parkinson's disease and seven (18%) as Parkinsonism; 44 patients were treated by madopar, artane, or amantadine, and only seven (16%) improved in movement. No patients exhibited improved eye movement. Of 4 patients treated with madopar and dopa agonists, 2 improved in movement. In addition, movement improved in 3 patients treated with madopar and monoamine oxidase B. CONCLUSION: PSP is a sporadic disease that often strikes middle or elderly individuals. There are no significant differences in age of onset between male and female patients, although disease progression is more rapid in female patients, likely because the time from symptom onset to disease diagnosis in females is less than in male. Akinetic-rigid features and early postural instability are the most common symptoms of onset. With disease progression, the incidence of vertical supranuclear ophthalmoplegia and akinetic-rigid features increases. MRI is a common, sensitive, and noninvasive supplemental test. However, PSP is frequently misdiagnosed as Parkinson's disease or Parkinsonism during the early stage, and anti-Parkinson treatments remain ineffective.
文摘Event-related potential (ERP) studies of cognitive function in Parkinson's disease (PD) have focused on P300 and N270. However, little is known regarding face recognition ERP in PD. The present study assessed cognitive function in PD patients using neuropsychological scales and analyzed N170 of visuospatial function impairment (VFI) in PD. Results showed that Montreal cognitive assessment can be used for assessing cognitive impairment when visuospatial functioning is changed during the early stage of PD. Face recognition has clinical significance for detecting changes in visuospatial functioning. However, N170 is not sensitive for detection of VFI in PD, which implies that VFI does not appear in the stage of structure coding in face recognition. In addition, VFI affects face recognition.
基金the National Natural Science Foundation of China,No.NSFC 81872107 and No.NSFC 81872108。
文摘BACKGROUND Tumor-to-tumor metastasis(TTM)is an uncommon condition.Only a few cases of renal cell carcinoma(RCC)as donor tumor of TTM have been reported in literature,and none of these studies have described RCC metastasizing to synchronous pheochromocytoma(PCC).CASE SUMMARY The patient was a 54-year-old woman who presented with recurrent dull abdominal pain for six months,which was further aggravated for one more month.Enhanced computed tomography revealed a tumor mass in the right kidney and another mass in the left retroperitoneum/adrenal gland.Histopathology and immunochemistry of resected specimens confirmed the diagnosis of clear cell renal cell carcinoma(CCRCC)of the right kidney,and the left retroperitoneum revealed a typical PCC with CCRCC metastasis.Whole exome sequencing revealed the presence of a c.529A>T somatic mutation of the Von Hippel Lindau(VHL)gene in the metastasized CCRCC,which was also present in the primary right kidney CCRCC,as confirmed by Sanger sequencing.No VHL mutation was detected in the PCC or in normal right kidney tissue.Fluorescence in situ hybridization revealed loss of chromosome 3p in both the primary right kidney CCRCC and CCRCC metastasized to PCC in the left kidney.CONCLUSION This is the first case showing metastasis of CCRCC to PCC,thus leading to tumorto-tumor metastasis.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61435009,61235008,and 61405254).
文摘An all-fiber dumbbell-shaped dual-amplifier mode-locked Er-doped laser that can function in dissipative soliton resonance(DSR)regime is demonstrated.A nonlinear optical loop mirror(NOLM)and a nonlinear amplifying loop mirror(NALM)are employed to initiate the mode-locking pulses.Unlike conventional single-amplifier structure,the output peak power of which remains unchanged when pump power is varied,the proposed structure allows its output peak power to be tuned by changing the pump power of the two amplifiers while the pulse duration is directly determined by the amplifier of nonlinear amplifying loop mirror.The entire distribution maps of peak power and pulse duration clearly demonstrate that the two amplifiers are related to each other,and they supply directly a guideline for designing tunable peak power DSR fiber laser.Pulse width can change from 800 ps to 2.6 ns and peak power varies from 13 W to 27 W.To the best of our knowledge,the peak power tunable DSR pulse is observed for the first time in dumbbell-shaped Er-doped all-fiber mode-locked lasers.
基金Supported by Program of Key Laboratory of Zhuang and Yao Medicine[Gui Ke Ji Zi[2014]No.32]Project of Guangxi University of Chinese Medicine(H2014015).
文摘[Objectives]To make pharmacognostic identification of Euphorbia maculata L.and its related species.[Methods]The classical pharmacognostic identification method was adopted.[Results]The four main medicinal materials are very similar,the fluff can be seen in E.maculata and Euphorbia thymifolia L.,but not in Euphorbia prostrata Ait.and Euphorbia taihsiensis(Chaw et Koutnik)Oudejians;the tissue structure is basically the same;except for E.taihsiensis without non-glandular hairs,the powder has secretory cells,laticifers,cells,calcium oxalate crystals,fibers,vessels,and seed coat fragments.Through ultrasonic extraction with 80%ethanol,extraction with isobutanol,extending with chloroform∶ethyl acetate∶formic acid(5∶3∶0.3),developing color with 3%aluminum trichloride ethanol solution,under ultraviolet light(365 nm),the fluorescent spots of the same color appeared on the corresponding position of the chromatogram of the reference substance(quercetin,kaempferol).[Conclusions]It is not easy to distinguish the four medicinal materials by character identification and microscopic identification,while the thin-layer chromatography(TLC)is more reliable.
基金the Natural Science Foundation of China(No.32270302 and No.32030006)the Fundamental Research Funds for the Central Universities(SCU2022D003)。
文摘ACYL-CoA-BINDING PROTEINs(ACBPs)play crucial regulatory roles during plant response to hypoxia,but their molecular mechanisms remain poorly understood.Our study reveals that ACBP4 serves as a positive regulator of the plant hypoxia response by interacting with WRKY70,influencing its nucleocytoplasmic shuttling in Arabidopsis thaliana.Furthermore,we demonstrate the direct binding of WRKY70 to the ACBP4 promoter,resulting in its upregulation and suggesting a positive feedback loop.Additionally,we pinpointed a phosphorylation site at Ser638 of ACBP4,which enhances submergence tolerance,potentially by facilitating WRKY70's nuclear shuttling.Surprisingly,a natural variation in this phosphorylation site of ACBP4 allowed A.thaliana to adapt to humid conditions during its historical demographic expansion.We further observed that both phosphorylated ACBP4 and oleoyl-Co A can impede the interaction between ACBP4 and WRKY70,thus promoting WRKY70's nuclear translocation.Finally,we found that the overexpression of orthologous Bna C5.ACBP4and Bna A7.WRKY70 in Brassica napus increases submergence tolerance,indicating their functional similarity across genera.In summary,our research not only sheds light on the functional significance of the ACBP4 gene in hypoxia response,but also underscores its potential utility in breeding flooding-tolerant oilseed rape varieties.
基金supported by the National Key R&D Program of China(Grant 2022YFC3601900 to G.H.L.,2022YFC3601903,and 2022YFC3601905 to C.J.L.,2019YFA0111900 to Y.J.)the National Natural Science Foundation of China(Grant Nos.82261160397,82272560,81922017 to C.J.L.)+4 种基金the Hunan Provincial Science and Technology Department(2023JJ30896 to C.J.L.,2023JJ40965 to L.L.)the Key Research and Development Program of Hunan Province(2022SK2023 to C.J.L.)Science and Technology Innovation Program of Hunan Province(2023RC1027 to C.J.L.,2022RC1009 to J.W.,and 2022RC3075 to C.Z.)The NSFC/RGC Joint Research Scheme,the Research Grants Council(UGC)of the Hong Kong Special Administrative Region and the National Natural Science Foundation of China(NSFC/RGC Project No.N_CUHK483/22 to Y.J.)the Center for Neuromusculoskeletal Restorative Medicine[CNRM at InnoHK,to Y.J.]by Innovation and Technology Commission(ITC)of Hong Kong SAR,China.
文摘Obesity-induced chronic inflammation exacerbates multiple types of tissue/organ deterioration and stem cell dysfunction;however,the effects on skeletal tissue and the underlying mechanisms are still unclear.Here,we show that obesity triggers changes in the microRNA profile of macrophage-secreted extracellular vesicles,leading to a switch in skeletal stem/progenitor cell(SSPC)differentiation between osteoblasts and adipocytes and bone deterioration.Bone marrow macrophage(BMM)-secreted extracellular vesicles(BMM-EVs)from obese mice induced bone deterioration(decreased bone volume,bone microstructural deterioration,and increased adipocyte numbers)when administered to lean mice.Conversely,BMM-EVs from lean mice rejuvenated bone deterioration in obese recipients.We further screened the differentially expressed microRNAs in obese BMM-EVs and found that among the candidates,miR-140(with the function of promoting adipogenesis)and miR-378a(with the function of enhancing osteogenesis)coordinately determine SSPC fate of osteogenic and adipogenic differentiation by targeting the Pparα-Abca1 axis.BMM miR-140 conditional knockout mice showed resistance to obesity-induced bone deterioration,while miR-140 overexpression in SSPCs led to low bone mass and marrow adiposity in lean mice.BMM miR-378a conditional depletion in mice led to obesity-like bone deterioration.More importantly,we used an SSPC-specific targeting aptamer to precisely deliver miR-378a-3p-overloaded BMM-EVs to SSPCs via an aptamer-engineered extracellular vesicle delivery system,and this approach rescued bone deterioration in obese mice.Thus,our study reveals the critical role of BMMs in mediating obesity-induced bone deterioration by transporting selective extracellular-vesicle microRNAs into SSPCs and controlling SSPC fate.