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THEORETICAL RESULTS ON THE EXISTENCE,REGULARITY AND ASYMPTOTIC STABILITY OF ENHANCED PULLBACK ATTRACTORS:APPLICATIONS TO 3D PRIMITIVE EQUATIONS
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作者 王仁海 郭柏灵 黄代文 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2493-2518,共26页
Several new concepts of enhanced pullback attractors for nonautonomous dynamical systems are introduced here by uniformly enhancing the compactness and attraction of the usual pullback attractors over an infinite forw... Several new concepts of enhanced pullback attractors for nonautonomous dynamical systems are introduced here by uniformly enhancing the compactness and attraction of the usual pullback attractors over an infinite forward time-interval under strong and weak topologies.Then we provide some theoretical results for the existence,regularity and asymptotic stability of these enhanced pullback attractors under general theoretical frameworks which can be applied to a large class of PDEs.The existence of these enhanced attractors is harder to obtain than the backward case[33],since it is difficult to uniformly control the long-time pullback behavior of the systems over the forward time-interval.As applications of our theoretical results,we consider the famous 3D primitive equations modelling the large-scale ocean and atmosphere dynamics,and prove the existence,regularity and asymptotic stability of the enhanced pullback attractors in V×V and H^(2)×H^(2) for the time-dependent forces which satisfy some weak conditions. 展开更多
关键词 3D primitive equations pullback attractors REGULARITY FATTENING stability
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Gradient descent decomposition of force-field motor primitives optogenetically elicited for motor mapping of the murine lumbosacral spinal cord
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作者 Paola Salmas Vincent C.K Cheung 《Zoological Research》 SCIE CAS CSCD 2023年第3期604-619,共16页
Generating diverse motor behaviors critical for survival is a challenge that confronts the central nervous system(CNS)of all animals.During movement execution,the CNS performs complex calculations to control a large n... Generating diverse motor behaviors critical for survival is a challenge that confronts the central nervous system(CNS)of all animals.During movement execution,the CNS performs complex calculations to control a large number of neuromusculoskeletal elements.The theory of modular motor control proposes that spinal interneurons are organized in discrete modules that can be linearly combined to generate a variety of behavioral patterns.These modules have been previously represented as stimulus-evoked force fields(FFs)comprising isometric limb-endpoint forces across workspace locations.Here,we ask whether FFs elicited by different stimulations indeed represent the most elementary units of motor control or are themselves the combination of a limited number of even more fundamental motor modules.To probe for potentially more elementary modules,we optogenetically stimulated the lumbosacral spinal cord of intact and spinalized Thy1-ChR2 transgenic mice(n=21),eliciting FFs from as many single stimulation loci as possible(20-70 loci per mouse)at minimally necessary power.We found that the resulting varieties of FFs defied simple categorization with just a few clusters.We used gradient descent to further decompose the FFs into their underlying basic force fields(BFFs),whose linear combination explained FF variability.Across mice,we identified 4-5 BFFs with partially localizable but overlapping representations along the spinal cord.The BFFs were structured and topographically distributed in such a way that a rostral-to-caudal traveling wave of activity across the lumbosacral spinal cord may generate a swing-to-stance gait cycle.These BFFs may represent more rudimentary submodules that can be flexibly merged to produce a library of motor modules for building different motor behaviors. 展开更多
关键词 Motor mapping OPTOGENETICS Spinal cord Motor primitives Traveling wave
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ON THE RIGOROUS MATHEMATICAL DERIVATION FOR THE VISCOUS PRIMITIVE EQUATIONS WITH DENSITY STRATIFICATION
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作者 蒲学科 周文利 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1081-1104,共24页
In this paper, we rigorously derive the governing equations describing the motion of a stable stratified fluid, from the mathematical point of view. In particular, we prove that the scaled Boussinesq equations strongl... In this paper, we rigorously derive the governing equations describing the motion of a stable stratified fluid, from the mathematical point of view. In particular, we prove that the scaled Boussinesq equations strongly converge to the viscous primitive equations with density stratification as the aspect ratio goes to zero, and the rate of convergence is of the same order as the aspect ratio. Moreover, in order to obtain this convergence result, we also establish the global well-posedness of strong solutions to the viscous primitive equations with density stratification. 展开更多
关键词 Boussinesq equations primitive equations density stratification hydrostatic approximation strong convergence
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Appropriate Garden Design of Primitive Ecology Based on the Indigenization of Environmental Ethics 被引量:1
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作者 章晓岗 王长富 《Journal of Landscape Research》 2010年第2期29-32,95,共5页
The accelerating urbanization process leads to aggravated environmental problems, thus garden design which is a creative activity connecting human and nature has attracted much attention, and also garden designers hav... The accelerating urbanization process leads to aggravated environmental problems, thus garden design which is a creative activity connecting human and nature has attracted much attention, and also garden designers have had to rethink about environmental ethics and morals. This study, from the perspective of environmental ethics, duly proposed the brand-new concept of 'appropriate garden of primitive ecology', proceeded from the orientation, form, value, theoretical basis, realistic significance, culture and consumption psychology of 'garden of primitive ecology', fully developed outstanding ecological wisdoms and morals in traditional Chinese garden culture, boosted garden designs to the environmental ethics level of eco-justice, to seek for the approach to 'garden of primitive ecology' with indigenous Chinese environmental ethic characteristics. 展开更多
关键词 Environmental ethics Garden of primitive ecology Appropriate design INDIGENIZATION Eco-justice
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ON THE 3D VISCOUS PRIMITIVE EQUATIONS OF THE LARGE-SCALE ATMOSPHERE 被引量:10
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作者 郭柏灵 黄代文 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期846-866,共21页
This paper is devoted to considering the three-dimensional viscous primitive equations of the large-scale atmosphere. First, we prove the global well-posedness for the primitive equations with weaker initial data than... This paper is devoted to considering the three-dimensional viscous primitive equations of the large-scale atmosphere. First, we prove the global well-posedness for the primitive equations with weaker initial data than that in [11]. Second, we obtain the existence of smooth solutions to the equations. Moreover, we obtain the compact global attractor in V for the dynamical system generated by the primitive equations of large-scale atmosphere, which improves the result of [11]. 展开更多
关键词 primitive equations Navier-Stokes equations global well-posedness smooth solutions
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Peripheral primitive neuroectodermal tumor of the kidney presenting with pulmonary tumor embolism: A case report 被引量:7
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作者 Sathya Chinnaa Chandan J Das +4 位作者 Sanjay Sharma Prabhjot Singh Amlesh Seth Suvendu Purkait Sandeep R Mathur 《World Journal of Radiology》 CAS 2014年第10期846-849,共4页
Peripheral primitive neuroectodermal tumor(PNET) of the kidney is a rare, aggressive tumor known for its recurrence and metastatic potential. Despite the frequency of venous extension to the renal veins and inferior v... Peripheral primitive neuroectodermal tumor(PNET) of the kidney is a rare, aggressive tumor known for its recurrence and metastatic potential. Despite the frequency of venous extension to the renal veins and inferior vena cava, pulmonary tumor embolism at the initial presentation is not common. We report a case of 22-year-old female with PNET of the kidney who presented with tumor embolism in the inferior vena cava(IVC) and bilateral pulmonary artery. The patient underwent surgical resection and histopathological analysis confirmed the presence of tumor within the IVC and pulmonary arteries. The patient received adjuvant chemotherapy and is currently doing well on follow-up. 展开更多
关键词 primitive neuroectodermal TUMOR PULMONARY TUMOR EMBOLISM COMPUTED tomography
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Huge peripheral primitive neuroectodermal tumor of the small bowel mesentery at nonage:A case report and review of the literature 被引量:3
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作者 Zhe Liu Yuan-Hong Xu +3 位作者 Chun-Lin Ge Jin Long Rui-Xia Du Ke-Jian Guo 《World Journal of Clinical Cases》 SCIE 2016年第9期306-309,共4页
Extraskeletal Ewing's sarcoma/peripheral primitive neuroectodermal tumor(E-EWS/pP NET) is a rare aggressive malignant small round cell tumor. In this report, we present the case of a 15-year-old boy who suffered f... Extraskeletal Ewing's sarcoma/peripheral primitive neuroectodermal tumor(E-EWS/pP NET) is a rare aggressive malignant small round cell tumor. In this report, we present the case of a 15-year-old boy who suffered from acute abdominal pain accompanied by hematemesis and melena, and was eventually diagnosed with E-EWS/p PNET. To date, there have been only five reported cases of E-EWS/pP NET of the small bowel including the patient in this report. To the best of our knowledge, this is the first documentation of a pP NET of the small bowel mesentery at nonage. All these have made this report rare and significant. 展开更多
关键词 EXTRASKELETAL Ewing’s SARCOMA Peripheral primitive neuroectodermal tumor Nonage Small BOWEL MESENTERY Spontaneous rupture
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Elimination of Computational Systematic Errors and Improvements of Weather and Climate System Models in Relation to Baroclinic Primitive Equations 被引量:2
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作者 钟青 陈家田 孙左令 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第6期1103-1112,共10页
The design of a total energy conserving semi-implicit scheme for the multiple-level baroclinic primitive equation has remained an unsolved problem for a long time. In this work, however, we follow an energy perfect co... The design of a total energy conserving semi-implicit scheme for the multiple-level baroclinic primitive equation has remained an unsolved problem for a long time. In this work, however, we follow an energy perfect conserving semi-implicit scheme of a European Centre for Medium-Range Weather Forecasts (ECMWF) type sigma-coordinate primitive equation which has recently successfully formulated. Some real-data contrast tests between the model of the new conserving scheme and that of the ECMWF-type of global spectral semi-implicit scheme show that the RMS error of the averaged forecast Height at 850 hPa can be clearly improved after the first integral week. The reduction also reaches 50 percent by the 30th day. Further contrast tests demonstrate that the RMS error of the monthly mean height in the middle and lower troposphere also be largely reduced, and some well-known systematical defects can be greatly improved. More detailed analysis reveals that part of the positive contributions comes from improvements of the extra-long wave components. This indicates that a remarkable improvement of the model climate drift level can be achieved by the actual realizing of a conserving time-difference scheme, which thereby eliminates a corresponding computational systematic error source/sink found in the currently-used traditional type of weather and climate system models in relation to the baroclinic primitive equations. 展开更多
关键词 fidelity scheme computational systematical errors baroclinic primitive equation
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A primitive mantle source for the Neoarchean mafic rocks from the Tanzania Craton 被引量:7
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作者 Y.A.Cook I.V.Sanislav +2 位作者 J.Hammerli T.G.Blenkinsop P.H.G.M.Dirks 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第6期911-926,共16页
Mafic rocks comprising tholeiitic pillow basalt, dolerite and minor gabbro form the basal stratigraphic unit in the ca. 2.8 to 2.6 Ga Geita Greenstone Belt situated in the NW Tanzania Craton. They outcrop mainly along... Mafic rocks comprising tholeiitic pillow basalt, dolerite and minor gabbro form the basal stratigraphic unit in the ca. 2.8 to 2.6 Ga Geita Greenstone Belt situated in the NW Tanzania Craton. They outcrop mainly along the southern margin of the belt, and are at least 50 million years older than the supracrustal assemblages against which they have been juxtaposed. Geochemical analyses indicate that parts of the assemblage approach high Mg-tholeiite (more than 8 wt.% MgO). This suite of samples has a restricted compositional range suggesting derivation from a chemically homogenous reservoir. Trace element modeling suggests that the mafic rocks were derived by partial melting within the spinel peridotite field from a source rock with a primitive mantle composition. That is, trace elements maintain primitive mantle ratios (Zr/Hf = 32-35, Ti/Zr - 107-147), producing flat REE and HFSE profles [(La/Yb)pm = 0.9 -1.3], with abundances of 3-10 times primitive mantle and with minor negative anomalies of Nb [(Nb/ La)pm - 0.6-0.8] and Th [(Th/La)pm = 0.6-0.9]. Initial isotope compositions (εNd) range from 1.6 to 2.9 at 2.8 Ga and plot below the depleted mantle line suggesting derivation from a more enriched source compared to present day MORB mantle. The trace element composition and Nd isotopic ratios are similar to the mafic rocks outcropping -50 km south. The mafic rocks outcropping in the Geita area were erupted through oceanic crust over a short time period, between -2830 and-2820 Ma; are compositionally homogenous, contain little to no associated terrigenous sediments, and their trace element composition and short emplacement time resemble oceanic plateau basalts. They have been interpreted to be derived from a plume head with a primitive mantle composition. 展开更多
关键词 Mafic rocks Archean Tanzania Craton primitive mantle MORB Oceanic plateau
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Long-term survival of a patient with a large adrenal primitive neuroectodermal tumor: A case report 被引量:1
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作者 Jun Dai Hong-Chao He +3 位作者 Xin Huang Fu-Kang Sun Yu Zhu Dan-Feng Xu 《World Journal of Clinical Cases》 SCIE 2019年第3期340-346,共7页
BACKGROUND Adrenal primitive neuroectodermal tumor(PNET) is an extremely rare malignant tumor with poor prognosis and of neural crest origin. Herein, we report a case of adrenal PNET and summarized its clinical and pa... BACKGROUND Adrenal primitive neuroectodermal tumor(PNET) is an extremely rare malignant tumor with poor prognosis and of neural crest origin. Herein, we report a case of adrenal PNET and summarized its clinical and pathological characteristics on the basis of 16 patients reported recently.CASE SUMMARY A female patient aged 25 years presented with right lumbago for 12 mo, and preoperative computed tomography showed a huge right adrenal mass. She received tumorectomy, and post-operative pathological examination showed adrenal PNET. After surgery, she underwent adjuvant chemotherapy and was followed up 31 mo after surgery. She received brachytherapy for right paracolic and hepatic metastases. She was alive and followed up for 60 mo. In available studies, only 57.14%(4/7) and 44.44%(4/9) were positive for the expression of neuron-specific enolase and synaptophysin, respectively, although CD99 expression was found in all the patients(100%; 10/10).CONCLUSION It is concluded that adrenal PNET is very rare and highly malignant, and histology is a golden standard in its diagnosis. Surgery and adjuvant therapy is the main treatment. 展开更多
关键词 primitive neuroectodermal TUMOR ADRENAL GLAND Case report
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Non-Acceleration Theorem in a Primitive Equation System: I. Acceleration of Zonal Mean Flow 被引量:10
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作者 吴国雄 陈彪 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第1期1-20,共20页
Non-acceleration theorem in a primitive equation system is developed to investigate the influences of waves on the mean flow variation against external forcing. Numerical results show that mechanical forcing overwhelm... Non-acceleration theorem in a primitive equation system is developed to investigate the influences of waves on the mean flow variation against external forcing. Numerical results show that mechanical forcing overwhelms thermal forcing in maintaining the mean flow in which the internal mechanical forcing associated with horizontal eddy flux of momentum plays the most important roles. Both internal forcing and external forcing are shown to be active and at the first place for the mean flow variations, whereas the forcing-induced mean meridional circulation is passive and secondary. It is also shown that the effects on mean flow of external mechanical forcing are concentrated in the lower troposphere, whereas those due to wave-mean flow interaction are more important in the upper troposphere. These act together and result in the vertically easterly shear in low latitudes and westerly shear in mid-latitudes. This vertical shear of mean flow is to some extent weakened by thermal forcing. 展开更多
关键词 Non-Acceleration Theorem in a primitive Equation System Acceleration of Zonal Mean Flow Mean
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Evolution from Primitive Life to Homo sapiens Based on Visible Genome Structures: The Amino Acid World 被引量:3
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作者 Kenji Sorimachi 《Natural Science》 2009年第2期107-119,共13页
It is not too much to say that molecular biology, including genome research, has progressed based on the determination of nucleotide or amino acid sequences. However, these ap-proaches are limited to the analysis of r... It is not too much to say that molecular biology, including genome research, has progressed based on the determination of nucleotide or amino acid sequences. However, these ap-proaches are limited to the analysis of relatively small numbers of the same genes among spe-cies. On the other hand, by graphical presenta-tion of the ratios of the numbers of amino acids present to the total numbers of amino acids presumed from the target gene(s) or genome or those of the numbers of nucleotides present to the total numbers of nucleotides calculated from the target gene(s) or genome, we can readily draw conclusions from extraordinarily huge data sets integrated by human intelli-gence. 1) Assuming polymerization of amino acids or nucleotides in a simulation analysis based on a random choice, proteins were formed by simple amino acid polymerization, while nucleotide polymerization to form nucleic acids encoding specific proteins needed certain specific control. These results proposed that protein formation chronologically preceded codon formation during the establishment of primitive life forms. In the prebiotic phase, amino acid composition was a dominant factor that determined protein characteristics;the “Amino Acid World”. 2) The genome is constructed homogeneou- sly from putative small units displaying similar codon usages and coding for similar amino acid compositions;the unit is a gene assembly en-coding 3,000 - 7,000 amino acid residues and this unit size is independent not only of genome size, but also of species. 3) In codon evolution, all nucleotide alterna-tions are correlated, not only in coding regions, but also in non-coding regions;the correlations can be expressed by linear formulas;y = ax + b, where “y” and “x” represent nucleotide con-tents, and “a” and “b” are constant. 4) The basic pattern of cellular amino acid compositions obtained from whole cell lysates is conserved from bacteria to Homo sapiens, and resembles that calculated from complete genomes. This basic pattern is characterized by a “star-shape” that changes slightly among species, and changes in amino acid composi-tion seem to reflect biological evolution. 5) Organisms can essentially be classified according to two codon patterns. Biological evolution due to nucleotide sub-stitutions can be expressed by simple linear formulas based on mathematical principles, while natural selection must affect species pre- servation after nucleotide alternations. There-fore, although Darwin’s natural selection is not directly involved in nucleotide alternations, it contributes obviously to the selection of nu-cleotide alternations. Thus, Darwin’s natural selection is doubtless an important factor in biological evolution. 展开更多
关键词 EVOLUTION primitive LIFE Form Genome NUCLEOTIDE Content Chargaff’s PARITY Rules CODON Amino Acids Linear Formula Classification
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Huge primitive neuroectodermal tumor of the pancreas:Report of a case and review of the literature 被引量:3
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作者 Thilo Welsch Gunhild Mechtersheimer +4 位作者 Sebastian Aulmann Sascha A Mueller Markus W Buechler Jan Schmidt Peter Kienle 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第37期6070-6073,共4页
Primitive neuroectodermal tumor (PNET) of the pancreas is an extremely rare tumor that usually occurs in children or young adults. We report a case of a 33-year-old male patient with an 18 cm × 18 cm × 16 cm... Primitive neuroectodermal tumor (PNET) of the pancreas is an extremely rare tumor that usually occurs in children or young adults. We report a case of a 33-year-old male patient with an 18 cm × 18 cm × 16 cm mass arising from the pancreatic body and tail with a one- day history of abdominal pain. Initial CT scan showed no signs of metastatic tumor spread. The tumor caused intrabdominal bleeding and the patient underwent primary tumor resection including partial gastrectomy, left pancreatic resection and splenectomy. Diagnosis of PNET was confi rmed by histology, immunohistochemistry and FISH analysis. All neoplastic cells were stained positive for MIC2-protein (CD99). Approximately one month after surgery, several liver metastases were observed and the patient underwent chemotherapy according to the Euro- Ewing protocol. Subsequent relaparotomy excluded any residual hepatic or extrahepatic abdominal metastases. Although PNET in the pancreas is an extremely rare entity, it should be considered in the diffential diagnosis of pancreatic masses, especially in young patients. This alarming case particularly illustrates that PNET in the pancreas although in an advanced stage can present with only a short history of mild symptoms. 展开更多
关键词 primitive neuroectodermal tumor PANCREAS MIC2-protein Ewing sarcoma Abdominal mass
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Characterization of Giardia cell nucleus:Its implication on the nature and origin of the primitive cell nucleus 被引量:3
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作者 LI JINGYAN (Department of Evolutionary Cell Biology, Laboratory of Cellular and Molecular Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.) 《Cell Research》 SCIE CAS CSCD 1995年第1期115-124,共10页
关键词 Origin of cell nucleus nucleus of Giardia primitive cell nucleus archezoa
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Genomic Instability in Cancer I: DNA-Repair Triggering Primitive Hereditary 4n-Skewed, Amitotic Division-System, the Culprit in EMT/MET/Metaplasia Cancer-Concepts 被引量:3
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作者 Kirsten H. Walen 《Journal of Cancer Therapy》 2018年第12期974-997,共24页
The objective was to gain proof of genome damage-repair induced mitotic slippage process (MSP) to 4n-diplochromosome skewed division-system, earlier suggested to have “cancer-deciding” consequences. Our damage-model... The objective was to gain proof of genome damage-repair induced mitotic slippage process (MSP) to 4n-diplochromosome skewed division-system, earlier suggested to have “cancer-deciding” consequences. Our damage-model showed two succeeding phases: molecular mutations for initiation of fitness-gained cells, and large chromosomal changes to aneuploidy from inherited DNA-breakage-repair inaccuracies. The mutations were gained while DNA-repair and DNA-replication, co-existed in the route to tetraploidy, a phenomenon also expressed for some existing unicellular organisms. These organisms also showed genome reductive, amitotic, meioticlike division, and was the origin of human genome conserved, self-inflicted 90° reorientation of the 4n nucleus relative to the cytoskeleton axis. In the in vitro DNA-damage model, this remarkable 4n-event deciding “flat-upright” cell-growth characteristics showed several consequences, for example, cancer-important, E-cadherin-β-catenin cell-to-cell adherence destruction, which gave diploid progeny cells, mobility freedom from cell contact inhibition, likely in renewal tissues. This 4n-skewed division-system with inheritance in progeny cells for repeat occurrences as mentioned for flat-up-right growth patterns is similar to claimed concepts of metaplasia-EMT/MET embryogenesis events in cancer evolution. A scrutiny of this literature, proof-wise invalidated this embryological concept by tetraploid 8C cells occurring in MET events and, was noted for small cell occurrence, i.e., diploidy from 4n-8C reductive division, an also event for tumor relapse cells, derived from genome damaging therapy agents. Pre-cancer hyperplasia reported MSP, cadherincatenin destruction and 90° perpendicularity to basal cell membrane. The DNA-damage-repair model can weed-out therapy-agents triggering 4n-skewed division. Cancer-control, beginning-information, is likely from mutational identity of the 4n derived fitness-gained cells. 展开更多
关键词 CANCER Evolution DNA-Damage-Repair Mitotic Slippage HEREDITARY primitive Tetraploidy 90° Amitotic Skewed DIVISION Fitness-Gain Embryogenesis-Type EMT/MET Human Cell Conservation
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Coordinating control of multiple rigid bodies based on motion primitives 被引量:1
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作者 Fan Wu Zhi-Yong Geng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期482-489,共8页
This paper studies the problem of coordinated motion generation for a group of rigid bodies. Two classes of coordinated motion primitives, relative equilibria and ma- neuvers, are given as building blocks for generati... This paper studies the problem of coordinated motion generation for a group of rigid bodies. Two classes of coordinated motion primitives, relative equilibria and ma- neuvers, are given as building blocks for generating coordi- nated motions. In a motion-primitive based planning frame- work, a control method is proposed for the robust execution of a coordinated motion plan in the presence of perturba- tions. The control method combines the relative equilibria stabilization with maneuver design, and results in a close- loop motion planning framework. The performance of the control method has been illustrated through a numerical sim- ulation. 展开更多
关键词 Coordinating control Motion plan execution Motion primitive. Relative equilibrium. Maneuver
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Extraction of Robot Primitive Control Rules from Natural Language Instructions 被引量:1
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作者 Guang-Hong Wang Ping Jiang Zu-Ren Feng 《International Journal of Automation and computing》 EI 2006年第3期282-290,共9页
A support vector rule based method is investigated for the construction of motion controllers via natural language training. It is a two-phase process including motion control information collection from natural langu... A support vector rule based method is investigated for the construction of motion controllers via natural language training. It is a two-phase process including motion control information collection from natural language instructions, and motion information condensation with the aid of support vector machine (SVM) theory. Self-organizing fuzzy neural networks are utilized for the collection of control rules, from which support vector rules are extracted to form a final controller to achieve any given control accuracy. In this way, the number of control rules is reduced, and the structure of the controller tidied, making a controller constructed using natural language training more appropriate in practice, and providing a fundamental rule base for high-level robot behavior control. Simulations and experiments on a wheeled robot are carried out to illustrate the effectiveness of the method. 展开更多
关键词 Support vector machines (SVMs) fuzzy neural networks motion primitives motion controller language instruction based training natural language programming.
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Total pelvic exenteration and a new model of diversion for giant primitive neuroectodermal tumor of prostate: A case report and review of the literature 被引量:1
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作者 Lichen Teng Liangjun Wei +5 位作者 Li Li Yongpeng Xu Yongsheng Chen Yan Cao Wentao Wang Changfu Li 《Asian Journal of Urology》 CSCD 2020年第2期181-185,共5页
The present study reports a rare primitive neuroectodermal tumor (PNET) of prostate.A 27-year-old male was admitted to Harbin Medical University Cancer Hospital (Harbin,China) for dysuria and dyschezia. Magnetic reson... The present study reports a rare primitive neuroectodermal tumor (PNET) of prostate.A 27-year-old male was admitted to Harbin Medical University Cancer Hospital (Harbin,China) for dysuria and dyschezia. Magnetic resonance imaging (MRI) revealed a large mass thatmay involve the bladder and rectum next to the prostate. Histopathological analysis of biopsyof prostate indicated mesenchymal origin tumor, and immunohistochemistric stainingconfirmed diagnosis of PNET of prostate. En bloc total pelvic exenteration and double barrelsigmoidostomy were performed. Double stomas in the skin incision were used for fecal andurinary diversion, respectively. Short-term outcome is satisfactory, while long-term efficacyremains to be poor. Clinical features of PNET of prostate should be paid much more attentionand radical surgery and adjuvant chemotherapy should be recommended. 展开更多
关键词 PROSTATE primitive neuroectodermal tumor Total pelvic exenteration Double barrel sigmoidostomy
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2-Competition Index of Primitive Digraphs Using Graph Theory 被引量:3
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作者 方炜 高玉斌 李忠善 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期320-324,共5页
Recently,scrambling index and competition index are widely applied to stochastic matrices and food webs. By analyzing the relationship of scrambling index and 2-competition index,n-「d/2」+ 1 was proved to be an upper... Recently,scrambling index and competition index are widely applied to stochastic matrices and food webs. By analyzing the relationship of scrambling index and 2-competition index,n-「d/2」+ 1 was proved to be an upper bound of the 2-competition2 index of a primitive digraph with exact d loops in this article.Moreover,the maximum index problem and the index set problem for the 2-competition index of primitive digraphs with minimally strong digraphs were settled. 展开更多
关键词 2-competition index primitive digraphs minimally strong digraphs
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Flag-transitive point-primitive 2-(v,k,4) symmetric designs and two dimensional classical groups 被引量:5
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作者 ZHOU Sheng-lin TIAN De-lu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期334-341,共8页
Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and ... Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and Xx = PGL2(3) where x is a point of D. 展开更多
关键词 Symmetric design FLAG-TRANSITIVE point-primitive two dimensional classical group.
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