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Frontogenesis and Frontolysis of a Cold Filament Driven by the Cross-Filament Wind and Wave Fields Simulated by a Large Eddy Simulation 被引量:1
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作者 Guojing LI Dongxiao WANG +3 位作者 Changming DONG Jiayi PAN Yeqiang SHU Zhenqiu ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期509-528,共20页
The variations of the frontogenetic trend of a cold filament induced by the cross-filament wind and wave fields are studied by a non-hydrostatic large eddy simulation. Five cases with different strengths of wind and w... The variations of the frontogenetic trend of a cold filament induced by the cross-filament wind and wave fields are studied by a non-hydrostatic large eddy simulation. Five cases with different strengths of wind and wave fields are studied.The results show that the intense wind and wave fields further break the symmetries of submesoscale flow fields and suppress the levels of filament frontogenesis. The changes of secondary circulation directions—that is, the conversion between the convergence and divergence of the surface cross-filament currents with the downwelling and upwelling jets in the filament center—are associated with the inertial oscillation. The filament frontogenesis and frontolysis caused by the changes of secondary circulation directions may periodically sharpen and smooth the gradient of submesoscale flow fields.The lifecycle of the cold filament may include multiple stages of filament frontogenesis and frontolysis. 展开更多
关键词 cold filament FRONTOGENESIS FRONTOLYSIS large eddy simulation
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Cold filament frontogenesis and frontolysis induced by thermal convection turbulence using large eddy simulation
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作者 Zewen Wu Guojing Li +1 位作者 Yunkai He Jintuan Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期26-34,共9页
The frontogenetic processes of a submesoscale cold filament driven by the thermal convection turbulence are studied by a non-hydrostatic large eddy simulation.The results show that the periodic changes in the directio... The frontogenetic processes of a submesoscale cold filament driven by the thermal convection turbulence are studied by a non-hydrostatic large eddy simulation.The results show that the periodic changes in the direction of the cross-filament secondary circulations are induced by the inertial oscillation.The change in the direction of the secondary circulations induces the enhancement and reduction of the horizontal temperature gradient during the former and later inertial period,which indicates that the frontogenetical processes of the cold filament include both of frontogenesis and frontolysis.The structure of the cold filament may be broken and restored by frontogenesis and frontolysis,respectively.The magnitude of the down-filament currents has a periodic variation,while its direction is unchanged with time.The coupling effect of the turbulent mixing and the frontogenesis and frontolysis gradually weakens the temperature gradient of the cold filament with time,which reduces frontogenetical intensity and enlarges the width of cold filament. 展开更多
关键词 cold filament FRONTOGENESIS FRONTOLYSIS thermal convection turbulence large eddy simulation
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Simple procedure for assessing diffuse subarachnoid hemorrhage successfully created using filament perforation method in mice
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作者 Tatsushi Mutoh Ryota Tochinai +3 位作者 Hiroaki Aono Masayoshi Kuwahara Yasuyuki Taki Tatsuya Ishikawa 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期77-81,共5页
The murine model of subarachnoid hemorrhage(SAH)is a valuable experimental tool for investigating molecular and cellular mechanisms,and the endovascular filament perforation technique can be used to simulate prominent... The murine model of subarachnoid hemorrhage(SAH)is a valuable experimental tool for investigating molecular and cellular mechanisms,and the endovascular filament perforation technique can be used to simulate prominent pathophysiological features observed after human SAH;however,current validation methods for assessing an appropriate SAH model are limited.Here,we introduce a simple procedure for se-lecting a mouse model of diffuse SAH.SAH was induced in 24 mice using a standard filament perforation method.After confirming survival at 24 h,SAH was scored 0-1 based on T2*-weighted images on whole-brain magnetic resonance imaging(MRI)and visual surveillance of the cisterna magna(CM)through the dura mater.The CM-based SAH grading correlated well with a reference parameter defined by extracted brain(r^(2)=0.53,p<0.0001).The receiver operating characteristic curve revealed a sensi-tivity of 85%and a specificity of 91%for detecting diffuse SAH,with a similar area under the curve(0.89±0.06[standard error of the mean])as the MRI-based grading(0.72±0.10,p=0.12).Our data suggest that confirming an SAH clot in the CM is a valuable way to select a clinically relevant diffuse SAH model that can be used in future experimental studies. 展开更多
关键词 cisterna magna clot distribution filament perforation mouse model subarachnoid hemorrhage
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Identification of Stability Domains for Flow Parameters in Fused Filament Fabrication Using Acoustic Emission
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作者 Zhen Li Lei Fu +2 位作者 Xinfeng Zou Baoshan Huang Fengshou Gu 《Journal of Dynamics, Monitoring and Diagnostics》 2024年第3期225-235,共11页
In Fused Filament Fabrication(FFF),the state of material flow significantly influences printing outcomes.However,online monitoring of these micro-physical processes within the extruder remains challenging.The flow sta... In Fused Filament Fabrication(FFF),the state of material flow significantly influences printing outcomes.However,online monitoring of these micro-physical processes within the extruder remains challenging.The flow state is affected by multiple parameters,with temperature and volumetric flow rate(VFR)being the most critical.The study explores the stable extrusion of flow with a highly sensitive acoustic emission(AE)sensor so that AE signals generated by the friction in the annular region can reflect the flow state more effectively.Nevertheless,the large volume and broad frequency range of the data present processing challenges.This study proposes a method that initially selects short impact signals and then uses the Fast Kurtogram(FK)to identify the frequency with the highest kurtosis for signal filtration.The results indicate that this approach significantly enhances processing speed and improves feature extraction capabilities.By correlating AE characteristics under various parameters with the quality of extruded raster beads,AE can monitor the real-time state of material flow.This study offers a concise and efficient method for monitoring the state of raster beads and demonstrates the potential of online monitoring of the flow states. 展开更多
关键词 acoustic emission center frequency fast kurtogram fused filament fabrication stability domains
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Diversity of filamentous fungi in organic layers of two forests in Zijin Mountain 被引量:3
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作者 宋福强 田兴军 +4 位作者 李重琦 杨昌林 陈斌 郝杰杰 朱静 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期273-279,共7页
A study was conducted to evaluate the cultivable filamentous fungal diversity in organic layers (L, F, and H layers) and A1 layer of two main forest types, Pinus massoniana and Liguidambar formasana mixed forest and Q... A study was conducted to evaluate the cultivable filamentous fungal diversity in organic layers (L, F, and H layers) and A1 layer of two main forest types, Pinus massoniana and Liguidambar formasana mixed forest and Quercus variabilis forest, in Zijin Mountain(325?N, 11848?E), Nanjing, China. A total of 67 taxa comprising 56 Deuteromycetes, 3 Zygomycetes, 5 Asco-mycetes and 3 unidentified fungi were recognized from samples from the forest floor of the two forest types. The most abundant group was Deuteromycetes. The dominant genera in both forests were Alternaria sp., Aspergillus sp., Cladosporium sp., Mucor sp., Penicillium sp., Rhizopus sp., Gliocladium sp. and Trichoderma spp. The fungal diversity was higher in the mixed forest than that in Q. variabilis forest. For both forest types, the maximum fungal diversity was found in layer F and there existed significantly different in fungal diversity between layer F and layer L. In the mixed forest, richness of fungi isolated from needle litter (P. massoniana) was lower than that from leaf litter (L. formasana). The richness of fungi from needle litter increased with the in-crease of forest floor depth, but for leaf litter, the fungal diversity decreased with the depth of forest floor. The co-species of fungi from the two forest types, as well as from two kinds of litters in mixed forest, increased with the depth of the forest floor. The succession of fungi along with the process of decomposition was discussed here. The results also showed that litter quality was a critical factor affecting fungal diversity. 展开更多
关键词 Zijin Mountain Forest type filamentous fungi DIVERSITY LITTER Quercus variabilis forest Pinus massoniana and Liguidambar formasana mixed fores
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GENETIC OPTIMIZATION OF HOT FILAMENT PARAMETERS IN HFCVD SYSTEM
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作者 宋胜利 左敦稳 +3 位作者 王珉 相炳坤 卢文壮 黎向锋 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期42-46,共5页
In HFCVD system the substrate temperature is a key factor which deeply affects the quality of diamond films. Th e magnitude and the variation of the substrate temperature must be limited in a suitable range to depo... In HFCVD system the substrate temperature is a key factor which deeply affects the quality of diamond films. Th e magnitude and the variation of the substrate temperature must be limited in a suitable range to deposit diamond films of uniform thickness over large areas. In this paper, the hot filament parameters are investigated on the basi s of GAs to realize a good substrate temperature profile. Computer simulations d emonstrate that on parameters optimized by GAs a uniform substrate temperatur e field can be formed over a relatively large circle area with R s=10 cm. 展开更多
关键词 hot filament chemical vapor deposition temperature field genetic algorithms optimization diamond fi lm
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Study on Limited Filamentous Sludge Bulking Test in A/O Activated Sludge Process
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作者 万玉山 孙凌峰 +2 位作者 贾春霞 李娜 雷春生 《Agricultural Science & Technology》 CAS 2014年第9期1620-1623,共4页
[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen (DO) on sludge bulking were explor... [Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen (DO) on sludge bulking were explored by changing the DO con- centration in the aerobiotic pool of NO system from the low load (0.25 kg COD/(kg MLSS.d)) and the medium to high load (0.55 kgCOD/(kg MLSSod)). [Result] In the NO activated sludge system, when the sludge load was 0.25 kg COD/(kg MLSS.d), DO=1.5 mg/L, the sludge index was at around 250, while when the sludge load- ing was 0.55 kg COD/(kg MLSS.d), DO=1.5 mg/L, the sludge index was close to 300, occurring the limited filamentous bulking. The bulked sludge still showed high removal rates to COD, SS, nitrogen and phosphorus. [Conclusion] It could improve the oxygen transfer rate and reduce the aeration rate at low DO conditions to achieve energy-saving. 展开更多
关键词 A/O process Limited filamentous sludge bulking Sludge load Energy saving
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Preliminary Investigation on a Sheet Plasma Produced by a Single Hot-Filament Cathode Discharge
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作者 冯哲 郭志刚 +1 位作者 蒲以康 张小章 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第3期304-309,共6页
A sheet plasma is generated by a mesh anode and a single hot-filament cathode with a DC power supply, and its characteristics are experimentally investigated. The sheet plasma is observed to locate around the anode. B... A sheet plasma is generated by a mesh anode and a single hot-filament cathode with a DC power supply, and its characteristics are experimentally investigated. The sheet plasma is observed to locate around the anode. Both electron density and electron temperature derived from the average energy of the energetic electrons in nitrogen are estimated to be 10s cm^-3 and 20- 40 eV, respectively, using the optical emission spectroscopy (OES) method based on a kinetic model of low-pressure nitrogen discharge. The electron density, electron temperature and their spatial distributions are found to be affected by the supplying voltage on the anode(70 V to 300 V), filament temperature (600℃ to 780℃) and gas pressure (2 Pa to 20 Pa). By adjusting these parameters the discharge status can be easily controlled. 展开更多
关键词 hot-filament cathode anode voltage filament temperature PRESSURE electron density electron temperature
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Study of Blended Antistatic PET Filament
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作者 仲蕾兰 何小军 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期46-49,共4页
From the effects of the composition of the three kinds ofblended systems, the antistatic agent content and theblending methods on the spinnability, the antistatic prop-erty, and the wash fastness of PET filament, it i... From the effects of the composition of the three kinds ofblended systems, the antistatic agent content and theblending methods on the spinnability, the antistatic prop-erty, and the wash fastness of PET filament, it is foundthat the antistatic behavior of the (PET) - (PEG) -(SDBS) - stearate quaternary system is improved greatlydue to the synergefic effect of the combined antistaticagents and the volume resistivity of the fiber made.Thereof reaches 10~8 ~ 10~9Ω·cm after being washed 20 tines in saponaceous water at 40℃. Its spinnability anddrawing behavior are good. The effect of the antistaticagent content on the mechanical property of PET fila-ment is also studied. 展开更多
关键词 ANTISTATIC electricity POLYESTER filamentS mechanical property ANTISTATIC PET filament ANTISTATIC agent synergetic effect volume RESISTIVITY
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Nuclear lamina-like filaments and nuclear matrix in Allium cepa as revealed by scanning electron microscopy
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作者 HAO SHUI, ALIN HU, DEZHANG JIN, MINGDA JIAO AND BAIQU HUANGInstitute of Genetics & Cytology, Northeast Normal University, Changchun 130024, China 《Cell Research》 SCIE CAS CSCD 1992年第2期153-163,共11页
In this study, freeze - fractured specimens of Allium cepa root tip meristems were examined under the scanning electron microscope (SEM). This technique permitted the visualization of the outer membrane of the nuclear... In this study, freeze - fractured specimens of Allium cepa root tip meristems were examined under the scanning electron microscope (SEM). This technique permitted the visualization of the outer membrane of the nuclear envelope with nuclear pore complexes and polyribosomes. Some of the cell nuclei prepared with this procedure had fissures of various widths on their nuclear envelopes through which the nuclear lamina-like filaments (LLF) underneath the nucleoplasmic side of the envelopes were clearly visible. The diameters of these filaments varied between 25 and 125 nm. Many of the LLFs showed granular thickenings at places, and were attached to the inner surface of nuclear envelope in some regions. Similar LLFs were also seen at the peripheries of the freeze -fractured faces of nuclei. Meanwhile,the spatial relation between the nuclear matrix filaments (NMF) and other nuclear structures (nucleoli, chromatin and peripheral lamina - like filaments) was revealed in these fractured preparations. In addition, the methods and techniques in studying the nuclear lamina morphology and the roles played by NMFs in activities of various nuclear structures were discussed in brief. 展开更多
关键词 nuclear lamina -like filaments nuclear matrix filaments Allium cepa freeze - fracture.
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基于“丝智活动”(Filamentality)的教育技术公共课教学设计应用实践
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作者 黄冠 《软件导刊.教育技术》 2010年第4期74-75,共2页
目前教育技术公共课已被国内广大教师接受且应用于教学活动中,基于简单易学的Filamentality进行教育技术公共课教学设计使教师将精力集中于对教学的设计。介绍如何应用Filamentality进行教育技术公共课教学设计,以提高教学效果。
关键词 丝智活动(filamentality) 教育技术公共课 教学设计 认知负荷
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Granulation of filamentous microorganisms in a sequencing batch reactor with saline wastewater 被引量:11
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作者 Zhihua Li Ting Zhang +1 位作者 Na Li Xiaochang Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期62-67,共6页
Proliferation of filamentous microorganisms frequently leads to operational failure for activate sludge systems. In this study, it was found that filamentous microorganisms could grow in compact granular structure wit... Proliferation of filamentous microorganisms frequently leads to operational failure for activate sludge systems. In this study, it was found that filamentous microorganisms could grow in compact granular structure with 5% sodium chloride in the substrate. In the early period of experiment, coccoid and rode-like bacteria predominated in the yellowish-brown granules, and later the white and the black granules were developed by filamentous microorganisms. The filamentous granules exhibited low porosity and fast settling velocity, and were more compact even than bacteria granules. It was hypothesized that the elevated pH in the later period might be a possible reason for the compact growth of filamentous granules. However, the bacteria granules showed the high bioactivity in terms of specific oxygen utilizing rate, and comprised of a wider diversity of compounds based on the thermogravimetric evaluation. The findings in this study demonstrated that filamentous microbes could form compact granular structure, which may encourage the utilization of filamentous microorganisms rather than the inhibition of their growth, as the latter is frequently used for sludge bulking control. 展开更多
关键词 aerobic granule sludge bulking filamentous microorganisms thermogravimetric analysis
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Approaches to functional genomics in filamentous fungi 被引量:19
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作者 Richard J Weld Kim M Plummer +1 位作者 Margaret A Carpenter Hayley J Ridgway 《Cell Research》 SCIE CAS CSCD 2006年第1期31-44,共14页
The study of gene function in filamentous fungi is a field of research that has made great advances in very recent years. A number of transformation and gene manipulation strategies have been developed and applied to ... The study of gene function in filamentous fungi is a field of research that has made great advances in very recent years. A number of transformation and gene manipulation strategies have been developed and applied to a diverse and rapidly expanding list of economically important filamentous fungi and oomycetes. With the significant number of fungal genomes now sequenced or being sequenced, functional genomics promises to uncover a great deal of new information in coming years. This review discusses recent advances that have been made in examining gene function in filamentous fungi and describes the advantages and limitations of the different approaches. 展开更多
关键词 functional genomics gene replacement filamentous fungi homologous recombination RNAI gene silencing OOMYCETES
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A New Giant Compsognathid Dinosaur with Long Filamentous Integuments from Lower Cretaceous of Northeastern China 被引量:7
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作者 JI Shu' an JI Qiang +1 位作者 LU Junchang YUAN Chongxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第1期8-15,共8页
A new compsognathid dinosaur, Sinocalliopteryx gigas gen. et sp. nov., is erected based on a complete skeleton from the Early Cretaceous Yixian Formation of western Liaoning, northeastern China. It shares the features... A new compsognathid dinosaur, Sinocalliopteryx gigas gen. et sp. nov., is erected based on a complete skeleton from the Early Cretaceous Yixian Formation of western Liaoning, northeastern China. It shares the features with Huaxiagnathus orientalis in having a manus as long as the humerus plus radius, very large and subequally long manual claws I and H, and reduced olecranon process on the ulna. But it differs from Huaxiagnathus orientalis in having the much large size, a very long maxillary process of premaxilla not extending the vertical level of the maxillary antorbital fossa, and the proportionally longer ulna and so on. Sinocalliopteryx gigas gen. et sp. nov. represents the largest species among the known compsognathid dinosaurs, suggesting the tendency of the body enlargement in compsognathids to some extent. The long filamentous integuments are attached to the whole body of this compsognathid, confirming that such integuments evolved firstly in the basal coelurosaurs. This new giant compsognathid was a fierce carnivorous theropod, as shown further by an incomplete dromaeosaurid leg inside its abdominal cavity. 展开更多
关键词 Compsognathidae SinocaUiopteryx gen. nov. giant skeleton filamentous integuments Yixian Formation Early Cretaceous western Liaoning
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Femtosecond filamentation induced fluorescence technique for atmospheric sensing 被引量:4
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作者 袁帅 陈瑞良 曾和平 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期43-51,共9页
Recent progress in filament-induced atmospheric sensing is reviewed. Self-guided propagation of ultrashort laser pulses in air induces laser filamentation. All molecules in the path of a filament can be dissociated in... Recent progress in filament-induced atmospheric sensing is reviewed. Self-guided propagation of ultrashort laser pulses in air induces laser filamentation. All molecules in the path of a filament can be dissociated into highly excited fragments, resulting in emission of characteristic fluorescence spectra. The fluorescence spectra provide information about the various molecules in the filaments. By using a filament-induced "fingerprinting" fluorescence technique, molecules in the atmosphere can be identified. 展开更多
关键词 femtosecond laser filamentATION remote sensing
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Stk2,a Mitogen-Activated Protein Kinase from Setosphaeria turcica,Specifically Complements the Functions of the Fus3 and Kss1 of Saccharomyces cerevisiae in Filamentation,Invasive Growth,and Mating Behavior 被引量:3
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作者 GU Shou-qin YANG Yang +10 位作者 LI Po ZHANG Chang-zhi FAN Yu ZHANG Xiao-yu TIAN Lan HAO Zhi-min CAO Zhi-yan GONG Xiao-dong FAN Yong-shan HAN Jian-min DONG Jin-gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2209-2216,共8页
Setosphaeria turcica,an essential phytopathogenic fungus,is the primary cause of serious yield losses in corn; however,its pathogenic mechanism is poorly understood.We cloned STK2,a newly discovered mitogen-activated ... Setosphaeria turcica,an essential phytopathogenic fungus,is the primary cause of serious yield losses in corn; however,its pathogenic mechanism is poorly understood.We cloned STK2,a newly discovered mitogen-activated protein kinase gene with a deduced amino acid sequence that is 96% identical to MAK2 from Phaeosphaeria nodorum,56% identical to KSS1 and 57% identical to FUS3 from Saccharomyces cerevisiae.To deduce Stk2 function in S.turcica and to identify the genetic relationship between STK2 and KSS1/FUS3 from S.cerevisiae,a restructured vector containing the open reading frame of STK2 was transformed into a fus3/kss1 double deletion mutant of S.cerevisiae.The results show that the STK2 complementary strain clearly formed pseudohyphae and ascospores,and the strain grew on the surface of the medium after rinsing with sterile water and the characteristics of the complementary strain was the same as the wild-type strain.Moreover,STK2 complemented the function of KSS1 in filamentation and invasive growth,as well as the mating behavior of FUS3 in S.cerevisiae,however,its exact functions in S.turcica will be studied in the future research. 展开更多
关键词 Setosphaeria turcica MAPK filamentATION invasive growth mating behavior
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Laminin-coated multifilament entubulation, combined with Schwann cells and glial cell line-derived neurotrophic factor, promotes unidirectional axonal regeneration in a rat model of thoracic spinal cord hemisection 被引量:5
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作者 Ling-Xiao Deng Nai-Kui Liu +3 位作者 Ryan Ning Wen Shuang-Ni Yang Xuejun Wen Xiao-Ming Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第1期186-191,共6页
Biomaterial bridging provides physical substrates to guide axonal growth across the lesion.To achieve efficient directional guidance,combinatory strategies using permissive matrix,cells and trophic factors are necessa... Biomaterial bridging provides physical substrates to guide axonal growth across the lesion.To achieve efficient directional guidance,combinatory strategies using permissive matrix,cells and trophic factors are necessary.In the present study,we evaluated permissive effect of poly(acrylonitrile-co-vinyl chloride)guidance channels filled by different densities of laminin-precoated unidirectional polypropylene filaments combined with Schwann cells,and glial cell line-derived neurotrophic factor for axonal regeneration through a T10 hemisected spinal cord gap in adult rats.We found that channels with filaments significantly reduced the lesion cavity,astrocytic gliosis,and inflammatory responses at the graft-host boundaries.The laminin coated low density filament provided the most favorable directional guidance for axonal regeneration which was enhanced by co-grafting of Schwann cells and glial cell line-derived neurotrophic factor.These results demonstrate that the combinatorial strategy of filament-filled guiding scaffold,adhesive molecular laminin,Schwann cells,and glial cell line-derived neurotrophic factor,provides optimal topographical cues in stimulating directional axonal regeneration following spinal cord injury.This study was approved by Indiana University Institutional Animal Care and Use Committees(IACUC#:11011)on October 29,2015. 展开更多
关键词 axonal regeneration extracellular molecule filament density HEMISECTION LAMININ neurotrophic factor Schwann cell spinal cord injury THORACIC transplantation
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Alreration of nuclear matrix-intermediate filament system and differential expression of nuclear matrix proteins during human hepatocarcinoma cell differentiation 被引量:4
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作者 Jian Tang Jing-Wen Niu +3 位作者 Dong-Hui Xu Zhi-Xing Li Qi-Fu Li Jin-An Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第20期2791-2797,共7页
AIM: To investigate the association between the configurational and compositional changes of nuclear matrix and the differentiation of carcinoma cells. METHODS: Cells cultured with or without 5 × 10^-3 mmol/L o... AIM: To investigate the association between the configurational and compositional changes of nuclear matrix and the differentiation of carcinoma cells. METHODS: Cells cultured with or without 5 × 10^-3 mmol/L of hexamethylene bisacetamide (HMBA) on Nickel grids were treated by selective extraction and prepared for whole mount observation under electron microscopy. The samples were examined under transmission electron microscope. Nuclear matrix proteins were selectively extracted and subjected to subcellular proteomics study. The protein expression patterns were analyzed by PDQuest software. Spots of differentially expressed nuclear matrix proteins were excised and subjected to in situ digestion with trypsin. The peptides were analyzed by matrix-assisted laser- desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Data were submitted for database searching using Mascot tool (www.matrixscience.com). RESULTS: The nuclear matrix (NM) and intermediate filament (IF) in SMMC-7721 hepatocarcinoma cells were found relatively sparse and arranged irregularly. The nuclear lamina was non-uniform, and two kinds of filaments were not tightly connected. After induction for differentiation by HMBA, the NM-IF filaments were concentrated and distributed uniformly. The heterogeneous population of filaments, including highly branched utrathin filaments could also be seen in the regular meshwork. The connection between the two kinds of filaments and the relatively thin, condensed and sharply demarcated lamina composed of intermediate- sized filaments was relatively fastened. Meanwhile, 21 NM proteins changed remarkably during SMMC-7721 cell differentiation. Four proteins, i.e. mutant Pystl, hypothetical protein, nucleophosminl, and LBP were downregulated, whereas four other proteins, eIF6, p44 subunit, 13-tubulin, and SIN3B were upregulated with the last one, SR2/ASF found only in the differentiated SMMC-7721 cells. CONCLUSION: The induced differentiation of SMMC-7721 cells by HMBA is accompanied by the configurational changes of nuclear matrix-intermediate filament (NM-IF) system and the compositional changes of nuclear matrix protein expression. These changes may be important morphological or functional indications of the cancer cell reversion. 展开更多
关键词 Nuclear matix-intermediate filament system Nuclear matrix protein Hexamethylamine bisacetamide SMMC-7721 cells Cell differentiation
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0.35%THz pulse conversion efficiency achieved by Ti:sapphire femtosecond laser filamentation in argon at 1 kHz repetition rate 被引量:5
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作者 Zhiqiang Yu Nan Zhang +5 位作者 Jianxin Wang Zijie Dai Cheng Gong Lie Lin Lanjun Guo Weiwei Liu 《Opto-Electronic Advances》 SCIE EI CAS 2022年第9期26-33,共8页
In this study,an optical setup for generating terahertz(THz)pulses through a two-color femtosecond laser filament was carefully designed to achieve a precise overlap of two-color laser pulses in space and time.β-bari... In this study,an optical setup for generating terahertz(THz)pulses through a two-color femtosecond laser filament was carefully designed to achieve a precise overlap of two-color laser pulses in space and time.β-barium borate(BBO),α-BBO,and a dual-wavelength plate were used to compensate the phase delay of the two-color lasers.Tilting ofα-BBO could further realize the precise spatial overlap of the two beams by counteracting the walk-off effect.The maximum out-put THz pulse energy reached 21μJ in argon gas when using a commercial Ti:sapphire laser with a pulse energy of 6 mJ at a 1 kHz repetition rate.The corresponding conversion efficiency exceeded 0.35%. 展开更多
关键词 femtosecond laser filaments walk-off effect conversion efficiency
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Construction and Virulence of Filamentous Hemagglutinin Protein B1 Mutant of Pasteurella multocida in Chickens 被引量:2
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作者 GUO Dong-chun SUN Yan +7 位作者 ZHANG Ai-qin LIU Jia-sen LU Yan LIU Pei-xin YUAN Dong-wei JIANG Qian SI Chang-de QU Lian-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2268-2275,共8页
Pasteurella multocida, a Gram-negative nonmotile coccobacillus, is the causative agent of fowl cholera, bovine hemorrhagic septicemia, enzoonotic pneumonia and swine atropic rhinitis. Two filamentous hemagglutinin gen... Pasteurella multocida, a Gram-negative nonmotile coccobacillus, is the causative agent of fowl cholera, bovine hemorrhagic septicemia, enzoonotic pneumonia and swine atropic rhinitis. Two filamentous hemagglutinin genes, fhaB1 and JhaB2, are the potential virulence factors. In this study, an inactivationfhaB1 mutant ofP. multocida in avian strain C48-102 was constructed by a kanamycin-resistance cassette. The virulence of thefhaB1 mutant and the wild type strain was assessed in chickens by intranasal and intramuscular challenge. The inactivation offhaB1 resulted in a high degree of attenuation when the chickens were challenged intranasally and a lesser degree when challenged intramuscularly. ThefhaB1 mutant and the wild type strain were investigated their sensitivity to the antibody-dependent classical complement-mediated killing pathway in 90% convalescent chicken serum. ThefhaB1 mutant was serum sensitive as the viability has reduced between untreated serum and heat inactivated chicken serum (P〈0.007). These results confirmed that FhaB1 played the critical roles in the bacterial pathogenesis and further studies were needed to investigate the mechanism which caused reduced virulence of the fhaB1 mutant. 展开更多
关键词 Pasteurella multocida filamentous hemagglutinin B 1 PATHOGENICITY VIRULENCE
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