With the successful hosting of the Beijing Olympic Games in 2008 and the World Exposition Shanghai China 2010,English,next to our mother tongue,has become the most important language in China.Therefore,learning Englis...With the successful hosting of the Beijing Olympic Games in 2008 and the World Exposition Shanghai China 2010,English,next to our mother tongue,has become the most important language in China.Therefore,learning English well is very important for most Chinese people.However,learning a foreign language well is not easy.We have to master several learning strategies and methods to learn it successfully.This paper will help all the foreign language learners to find the effective way in learning the second foreign languge.The paper mainly talks about two aspects:improving the abilities in listening,speaking and reading in order to communicate well;developing the ability of writing in English and perfecting the function of social communication.It gives out the concrete methods in listening,speaking,reading,writing,and translating.The authors hope that the paper would be helpful in assisting the foreign language learners to learn and master the second foreign language.展开更多
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
In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test ...In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test on the actual production capacity of land and the forecasted production capacity of land in 2007 and 2008, and then conduct comprehensive forecast of the land production potential in Guizhou Province in 2020. On this basis, considering the nutritional standards needed by three kinds of life type (dressing warmly and eating one's fill, well-off life, relatively affluent life), we evaluate the land production potential in Guizhou Province under the project of returning farmland to forest. Based on the evaluation results, we put forth the relevant recommendations for achieving sustainable land use in the context of returning farmland to forest in Guizhou Province.展开更多
The Naga Hills Ophiolite(NHO)belt in the Indo-Myanmar range(IMR)represents a segment of Tethyan oceanic crust and upper mantle that was involved in an eastward convergence and collision of the Indian Plate with the Bu...The Naga Hills Ophiolite(NHO)belt in the Indo-Myanmar range(IMR)represents a segment of Tethyan oceanic crust and upper mantle that was involved in an eastward convergence and collision of the Indian Plate with the Burmese Plate during the Late Cretaceous-Eocene.Here,we present a detailed petrological and geochemical account for the mantle and crustal sections of NHO,northeastern India to address(i)the mantle processes and tectonic regimes involved in their genesis and(ii)their coherence in terms of the thermo-tectonic evolution of Tethyan oceanic crust and upper mantle.The NHO suite comprises well preserved crustal and mantle sections discretely exposed at Moki,Ziphu,Molen,Washelo and Lacham areas.The ultramafic-mafic lithologies of NHO are mineralogically composed of variable proportions of olivine,orthopyroxene,clinopyroxene and plagioclase.The primary igneous textures for the mantle peridotites have been overprinted by extensive serpentinisation whereas the crustal section rocks reflect crystal cumulation in a magma chamber.Chondrite normalised REE profiles for the cumulate peridotite-olivine gabbro-gabbro assemblage constituting the crustal section of NHO show flat to depleted LREE patterns consistent with their generation from depleted MORB-type precursor melt in an extensional tectonic setting,while the mantle peridotites depict U-shaped REE patterns marked by relative enrichment of LREE and HREE over MREE.These features collectively imply a dual role of depleted MORB-type and enriched arc-type mantle components for their genesis with imprints of melt-rock and fluid-rock interactions.Tectonically,studied lithologies from NHO correspond to a boninitic to slab-proximal Island Arc Tholeiite affinity thereby conforming to an intraoceanic supra subduction zone(SSZ)fore-arc regime coherent with the subduction initiation process.The geochemical attributes for the crustal and mantle sections of NHO as mirrored by Zr/Hf,Zr/Sm,Nb/Ta,Zr/Nb,Nb/U,Ba/Nb,Ba/Th,Ba/La and Nd/Hf ratios propound a two-stage petrogenetic process:(i)a depleted fore arc basalt(FAB)type tholeiitic melt parental to the crustal lithologies was extracted from the upwelling asthenospheric mantle at SSZ fore-arc extensional regime thereby rendering a refractory residual upper mantle;(ii)the crust and upper mantle of the SSZ fore arc were progressively refertilised by boninitic melts generated in response to subduction initiation and slab-dehydration.The vestiges of Tethyan oceanic lithosphere preserved in NHO represent an accreted intra-oceanic fore arc crust and upper mantle section which records a transitional geodynamic evolution in a SSZ regime marked by subduction initiation,fore arc extension and arc-continent accretion.展开更多
Objective： To screen and identify key genes differentially displayed in mouse fore stomach carcinoma, in order to elucidate the molecular mechanism underlying carcinogenesis. Methods： The animal models complied wit...Objective： To screen and identify key genes differentially displayed in mouse fore stomach carcinoma, in order to elucidate the molecular mechanism underlying carcinogenesis. Methods： The animal models complied with each period of NIH mouse fore stomach carcinoma induced by N-Nitrososarcosineethylester （NSEE） were used in this study. The mice were euthanized on days 14, 28, 56, 77 and 84, respectively, after NSEE-piped treatment, and classified according to their pathologies. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique and screened by using Reverse Northern blot. Bioinformatics were employed to analyze the results observed. After identification, ten fragments were cloned and matched with GENEBANK database through homologous analysis. Results： One gene was found identical to splicing factor 3b subunit 1 （Sf3bl）, while seven fragments hold the homology of known cDNA clones. In contrast, other two fragments had extremely low identity to any genes registered in GENBANK databases. Conclusion： It is the first time to demonstrate in this study that splicing factor3b, subunitl （Sf3bl） is related to mouse fore stomach carcinoma. Furthermore, ESC-3 and ESC-4 are suggested to contribute to the development of mouse fore stomach carcinoma, thus may be candidates of new targets of oncogenes.展开更多
This paper investigates characteristics of ironless permanent magnet linear synchronous motor(PMLSM)based on Halbach array used for medium-speed(200km/h)maglev train.Long primary ironless coil is laid in the middle of...This paper investigates characteristics of ironless permanent magnet linear synchronous motor(PMLSM)based on Halbach array used for medium-speed(200km/h)maglev train.Long primary ironless coil is laid in the middle of track and the Halbach permanent magnet array is attached to the bottom of each bogie as a source of traction,U-shape electromagnets at the both sides of the train for levitation.Two dimensional analytical model of single-sided ironless PMLSM based on Halbach array is established,using linear overlay method,the no-load air gap magnetic field is calculated firstly,winding current density distribution is obtained for calculating the characteristics of thrust and normal force against power angle,including force characteristics with equal and unequal pole pitch,the influence of steel sleeper,etc.Besides,the mathematical model for this type motor is built by 3D finite element method,the traction characteristics of medium-speed maglev under maximum speed 200km/h are calculated.The characteristics of this type motor are satisfactory owing to there is no detent force in the motor and thrust force reach maximum meanwhile normal force can be eliminated.Calculation method is verified by comparing finite element results,experimental result on a 200kW type motor further validates the accuracy of calculation and some important conclusions are obtained.展开更多
The significance and status of the teachers'professional development make the education system and the society pay more and more attentions.The article elaborates the internal contact of curriculum discourse and t...The significance and status of the teachers'professional development make the education system and the society pay more and more attentions.The article elaborates the internal contact of curriculum discourse and teachers'professional development from a few respects such as the rationality of curriculum discourse,the long-term nature of the teachers'professional development and many factors affecting the teachers'professional development.The article also analyzes the external and internal factors influencing Tibet foreign language teachers'professional development,and puts forward the corresponding countermeasures in the light of these problems.展开更多
Objective： To find out the relationship of the expressions of proliferating cell nuclear antigen （proliferating cell nuclear antigen, PCNA）, alkaline phosphotase （alkaline phosphotase, AKP） and acid phosphotase ...Objective： To find out the relationship of the expressions of proliferating cell nuclear antigen （proliferating cell nuclear antigen, PCNA）, alkaline phosphotase （alkaline phosphotase, AKP） and acid phosphotase （acid phosphotase, ACP） with the development of mouse fore stomach cancerization. Methods： The animal models, including the various stages during the development of NIH mouse fore stomach carcinoma, were made by N-Nitrososarcosineethylester （N-Nitrososarcosineethylester, NSEE）. The mice were sacrificed on the 14th, 28th, 42nd, 56th, 70th and 84th days respectively after mice were irrigated with NSEE. The fore stomach was taken out and dissected. The methods of histopathology, immunohistochemistry and isoenzyme electrophoresis were adopted to study the dynamic changes of cell shape and expression of PCNA, AKP and ACP. Results： On the 42nd and 56th days after NSEE treatment, the expression of PCNA increased gradually along with the cancerization. Comparing with the control, there were significant differences （P〈0.05）. On the 70th and 84th days, the expression of PCNA increased further （compared with the control P〈0.01）. The activity of AKP increased gradually along with the cancerization. On the 14th, 28th, 42nd and 56th days, there were significant differences （P〈0.05）; on the 70th and 84th days, the activity of AKP increased further （P〈0.01）. The activity of ACP also increased on the 14th, 28th, 42nd and 56th days, and there were significant differences on the 70th days （P〈0.05） and on the 84th days （P〈0.01） compared with the control. Conclusion： During the carcinogenesis of NIH mouse fore stomach, the expressions of PCNA, AKP and ACP increased gradually and were consisted with the changes of cell shapes.展开更多
In the paper, a solution of one dimensional fore region pressure build up is put forward. The performance of spring supported thrust bearing is carried out with 3 dimensional thermo elasto hydrodynamic (TEHD) lub...In the paper, a solution of one dimensional fore region pressure build up is put forward. The performance of spring supported thrust bearing is carried out with 3 dimensional thermo elasto hydrodynamic (TEHD) lubrication theory inclusive of inlet pressure build up, thermal elastic distortion of pad and thermal effect. The effects of fore region pressure build up and the variation of some operating conditions on the performance of the pad are studied.展开更多
AFM is used for forming silicon dioxide as a layer (mask) on the silicon wafer surface (100) during the cutting process in ambient atmosphere. The silicon dioxide is made through reaction of silicon and oxygen in the ...AFM is used for forming silicon dioxide as a layer (mask) on the silicon wafer surface (100) during the cutting process in ambient atmosphere. The silicon dioxide is made through reaction of silicon and oxygen in the atmosphere. As a result of the anisotropic behavior of single crystalline silicon, the etching rates in alkaline solution depend greatly on the various crystal orientations. The anisotropic etching behaviors in KOH solution and reasons of crystalline silicon are described. Effect of etching conditions such as etching temperature and KOH concentration of the alkaline solution on height of the micro-protuberances has been described.展开更多
Background The respiratory system changes with age and a better understanding of the changes contribute to detect and prevent respiratory dysfunctions in old population. The purpose of this study was to observe age-as...Background The respiratory system changes with age and a better understanding of the changes contribute to detect and prevent respiratory dysfunctions in old population. The purpose of this study was to observe age-associated changes of pulmonary function parameters in healthy young adults and the elderly. Methods A cross-sectional study was conducted among 600 male and female subjects aged 19 to 92 years. The subjects were divided into three groups by age： young adult （19-39 years）, middle-aged adult （40-59 years）, and the elderly （〉60 years）. The pulmonary function was measured with routine examination methods and 13 parameters including vital capacity （VC）, residual volume （RV）, functional residual capacity （FRC）, total lung capacity （TLC）, RV/TLC, forced vital capacity （FVC）, forced expiratory volume in one second （FEV1）, FEV1/FVC, peak expiratory flow （PEF）, forced expiratory flow at 25% of FVC exhaled （FEF25）, forced expiratory flow at 50% of FVC exhaled （FEF50）, diffusion capacity of the lung for carbon monoxide （DLCO）, and specific diffusion capacity of CO （KCO） were collected and analyzed. Changes in pulmonary function parameters among the influence on FEVJFVC and RV were studied further. Results Ten pulmonary function parameters including VC, FVC, pre-elderly and elderly subjects, especially the aging FEV1, FEV1/FVC, PEF, FEF25, FEF50, TLC, DLCO and KCO decreased significantly with age in both male and female subjects （P 〈0.01）. RV and RV/TLC were increased with age （P 〈0.01）. FRC remained stable during aging. Except FRC, the linear relationship was significant between age and other pulmonary function parameters. In the pre-elderly and elderly subjects, RV had a non-significantly increasing tendency with age （P 〉0.05）, and FEV1/FVC did not change significantly with age （P 〉0.05）. Conclusion Total pulmonary function was declined tendency of RV and decreasing tendency of FEV1/FVC with advancing age, but FRC was stable, and the increasing obviously slowed down in the pre-elderly and elderly subjects.展开更多
Object detection is the most fundamental but challenging issues in the field of computer vision.Object detection identifies the presence of various individual objects in an image.Great success is attained for object ...Object detection is the most fundamental but challenging issues in the field of computer vision.Object detection identifies the presence of various individual objects in an image.Great success is attained for object detection/recognition problems in the controlled environment,but still,the problem remains unsolved in the uncontrolled places,particularly,when the objects are placed in arbitrary poses in an occluded and cluttered environment.In the last few years,a lots of efforts are made by researchers to resolve this issue,because of its wide range of applications in computer vision tasks,like content-enabled image retrieval,event or activity recognition,scene understanding,and so on.This review provides a detailed survey of 50 research papers presenting the object detection techniques,like machine learning-based techniques,gradient-based techniques,Fast Region-based Convolutional Neural Network(Fast R-CNN)detector,and the foreground-based techniques.Here,the machine learning-based approaches are classified into deep learning-based approaches,random forest,Support Vector Machine(SVM),and so on.Moreover,the challenges faced by the existing techniques are explained in the gaps and issues section.The analysis based on the classification,toolset,datasets utilized,published year,and the performance metrics are discussed.The future dimension of the research is based on the gaps and issues identified from the existing research works.展开更多
People love mountains and waters, taking delight in talking about landscape. Some draw landscape paintings because they like mountains and waters, placing love on forests and springs.However, drawing mountains-and-wat...People love mountains and waters, taking delight in talking about landscape. Some draw landscape paintings because they like mountains and waters, placing love on forests and springs.However, drawing mountains-and-waters paintings is no easy job, just like climbing mountains, which requires painters to learn from ancient prominent personage and walk a thousand li without any falsity and trickery.展开更多
文摘With the successful hosting of the Beijing Olympic Games in 2008 and the World Exposition Shanghai China 2010,English,next to our mother tongue,has become the most important language in China.Therefore,learning English well is very important for most Chinese people.However,learning a foreign language well is not easy.We have to master several learning strategies and methods to learn it successfully.This paper will help all the foreign language learners to find the effective way in learning the second foreign languge.The paper mainly talks about two aspects:improving the abilities in listening,speaking and reading in order to communicate well;developing the ability of writing in English and perfecting the function of social communication.It gives out the concrete methods in listening,speaking,reading,writing,and translating.The authors hope that the paper would be helpful in assisting the foreign language learners to learn and master the second foreign language.
基金This paper was supported by Chinese Program for High Technology Research and Development (2003AA209030) Scien-tific Research Foundation for doctoral supervising laboratory State Education Ministry (20030284044) and National Natural Sc
文摘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.
基金Supported by 2009 Youth Project of Social Science Planning in Guizhou Province (09GHQNHQ04)Agricultural Scientific and Technological Project in Guizhou Province (20103014)
文摘In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test on the actual production capacity of land and the forecasted production capacity of land in 2007 and 2008, and then conduct comprehensive forecast of the land production potential in Guizhou Province in 2020. On this basis, considering the nutritional standards needed by three kinds of life type (dressing warmly and eating one's fill, well-off life, relatively affluent life), we evaluate the land production potential in Guizhou Province under the project of returning farmland to forest. Based on the evaluation results, we put forth the relevant recommendations for achieving sustainable land use in the context of returning farmland to forest in Guizhou Province.
基金the funds from Department of Science and Technology,Govt.of India under ECR/2018/000309 project。
文摘The Naga Hills Ophiolite(NHO)belt in the Indo-Myanmar range(IMR)represents a segment of Tethyan oceanic crust and upper mantle that was involved in an eastward convergence and collision of the Indian Plate with the Burmese Plate during the Late Cretaceous-Eocene.Here,we present a detailed petrological and geochemical account for the mantle and crustal sections of NHO,northeastern India to address(i)the mantle processes and tectonic regimes involved in their genesis and(ii)their coherence in terms of the thermo-tectonic evolution of Tethyan oceanic crust and upper mantle.The NHO suite comprises well preserved crustal and mantle sections discretely exposed at Moki,Ziphu,Molen,Washelo and Lacham areas.The ultramafic-mafic lithologies of NHO are mineralogically composed of variable proportions of olivine,orthopyroxene,clinopyroxene and plagioclase.The primary igneous textures for the mantle peridotites have been overprinted by extensive serpentinisation whereas the crustal section rocks reflect crystal cumulation in a magma chamber.Chondrite normalised REE profiles for the cumulate peridotite-olivine gabbro-gabbro assemblage constituting the crustal section of NHO show flat to depleted LREE patterns consistent with their generation from depleted MORB-type precursor melt in an extensional tectonic setting,while the mantle peridotites depict U-shaped REE patterns marked by relative enrichment of LREE and HREE over MREE.These features collectively imply a dual role of depleted MORB-type and enriched arc-type mantle components for their genesis with imprints of melt-rock and fluid-rock interactions.Tectonically,studied lithologies from NHO correspond to a boninitic to slab-proximal Island Arc Tholeiite affinity thereby conforming to an intraoceanic supra subduction zone(SSZ)fore-arc regime coherent with the subduction initiation process.The geochemical attributes for the crustal and mantle sections of NHO as mirrored by Zr/Hf,Zr/Sm,Nb/Ta,Zr/Nb,Nb/U,Ba/Nb,Ba/Th,Ba/La and Nd/Hf ratios propound a two-stage petrogenetic process:(i)a depleted fore arc basalt(FAB)type tholeiitic melt parental to the crustal lithologies was extracted from the upwelling asthenospheric mantle at SSZ fore-arc extensional regime thereby rendering a refractory residual upper mantle;(ii)the crust and upper mantle of the SSZ fore arc were progressively refertilised by boninitic melts generated in response to subduction initiation and slab-dehydration.The vestiges of Tethyan oceanic lithosphere preserved in NHO represent an accreted intra-oceanic fore arc crust and upper mantle section which records a transitional geodynamic evolution in a SSZ regime marked by subduction initiation,fore arc extension and arc-continent accretion.
基金supported by the Zoology Key Subject of Henan Province.
文摘Objective： To screen and identify key genes differentially displayed in mouse fore stomach carcinoma, in order to elucidate the molecular mechanism underlying carcinogenesis. Methods： The animal models complied with each period of NIH mouse fore stomach carcinoma induced by N-Nitrososarcosineethylester （NSEE） were used in this study. The mice were euthanized on days 14, 28, 56, 77 and 84, respectively, after NSEE-piped treatment, and classified according to their pathologies. The differentially expressed genes were isolated from both normal and morbid tissues by mRNA differential display technique and screened by using Reverse Northern blot. Bioinformatics were employed to analyze the results observed. After identification, ten fragments were cloned and matched with GENEBANK database through homologous analysis. Results： One gene was found identical to splicing factor 3b subunit 1 （Sf3bl）, while seven fragments hold the homology of known cDNA clones. In contrast, other two fragments had extremely low identity to any genes registered in GENBANK databases. Conclusion： It is the first time to demonstrate in this study that splicing factor3b, subunitl （Sf3bl） is related to mouse fore stomach carcinoma. Furthermore, ESC-3 and ESC-4 are suggested to contribute to the development of mouse fore stomach carcinoma, thus may be candidates of new targets of oncogenes.
基金This work was supported in part by the National Key R&D Program of China under Grant 2017YFB1201003.
文摘This paper investigates characteristics of ironless permanent magnet linear synchronous motor(PMLSM)based on Halbach array used for medium-speed(200km/h)maglev train.Long primary ironless coil is laid in the middle of track and the Halbach permanent magnet array is attached to the bottom of each bogie as a source of traction,U-shape electromagnets at the both sides of the train for levitation.Two dimensional analytical model of single-sided ironless PMLSM based on Halbach array is established,using linear overlay method,the no-load air gap magnetic field is calculated firstly,winding current density distribution is obtained for calculating the characteristics of thrust and normal force against power angle,including force characteristics with equal and unequal pole pitch,the influence of steel sleeper,etc.Besides,the mathematical model for this type motor is built by 3D finite element method,the traction characteristics of medium-speed maglev under maximum speed 200km/h are calculated.The characteristics of this type motor are satisfactory owing to there is no detent force in the motor and thrust force reach maximum meanwhile normal force can be eliminated.Calculation method is verified by comparing finite element results,experimental result on a 200kW type motor further validates the accuracy of calculation and some important conclusions are obtained.
文摘The significance and status of the teachers'professional development make the education system and the society pay more and more attentions.The article elaborates the internal contact of curriculum discourse and teachers'professional development from a few respects such as the rationality of curriculum discourse,the long-term nature of the teachers'professional development and many factors affecting the teachers'professional development.The article also analyzes the external and internal factors influencing Tibet foreign language teachers'professional development,and puts forward the corresponding countermeasures in the light of these problems.
基金This work was supported by Henan Technologies R & D Project (No. 0424420043) and Henan Zoology Key Subject.
文摘Objective： To find out the relationship of the expressions of proliferating cell nuclear antigen （proliferating cell nuclear antigen, PCNA）, alkaline phosphotase （alkaline phosphotase, AKP） and acid phosphotase （acid phosphotase, ACP） with the development of mouse fore stomach cancerization. Methods： The animal models, including the various stages during the development of NIH mouse fore stomach carcinoma, were made by N-Nitrososarcosineethylester （N-Nitrososarcosineethylester, NSEE）. The mice were sacrificed on the 14th, 28th, 42nd, 56th, 70th and 84th days respectively after mice were irrigated with NSEE. The fore stomach was taken out and dissected. The methods of histopathology, immunohistochemistry and isoenzyme electrophoresis were adopted to study the dynamic changes of cell shape and expression of PCNA, AKP and ACP. Results： On the 42nd and 56th days after NSEE treatment, the expression of PCNA increased gradually along with the cancerization. Comparing with the control, there were significant differences （P〈0.05）. On the 70th and 84th days, the expression of PCNA increased further （compared with the control P〈0.01）. The activity of AKP increased gradually along with the cancerization. On the 14th, 28th, 42nd and 56th days, there were significant differences （P〈0.05）; on the 70th and 84th days, the activity of AKP increased further （P〈0.01）. The activity of ACP also increased on the 14th, 28th, 42nd and 56th days, and there were significant differences on the 70th days （P〈0.05） and on the 84th days （P〈0.01） compared with the control. Conclusion： During the carcinogenesis of NIH mouse fore stomach, the expressions of PCNA, AKP and ACP increased gradually and were consisted with the changes of cell shapes.
文摘In the paper, a solution of one dimensional fore region pressure build up is put forward. The performance of spring supported thrust bearing is carried out with 3 dimensional thermo elasto hydrodynamic (TEHD) lubrication theory inclusive of inlet pressure build up, thermal elastic distortion of pad and thermal effect. The effects of fore region pressure build up and the variation of some operating conditions on the performance of the pad are studied.
基金Sponsored by the Natural Science Foundation of China (Grant No.20271019), the Natural Science Foundation of Heilongjiang Province (Grant No.B200504) and the Education Department Foundation of Heilongjiang Province (Grant No.11511270).
文摘AFM is used for forming silicon dioxide as a layer (mask) on the silicon wafer surface (100) during the cutting process in ambient atmosphere. The silicon dioxide is made through reaction of silicon and oxygen in the atmosphere. As a result of the anisotropic behavior of single crystalline silicon, the etching rates in alkaline solution depend greatly on the various crystal orientations. The anisotropic etching behaviors in KOH solution and reasons of crystalline silicon are described. Effect of etching conditions such as etching temperature and KOH concentration of the alkaline solution on height of the micro-protuberances has been described.
文摘Background The respiratory system changes with age and a better understanding of the changes contribute to detect and prevent respiratory dysfunctions in old population. The purpose of this study was to observe age-associated changes of pulmonary function parameters in healthy young adults and the elderly. Methods A cross-sectional study was conducted among 600 male and female subjects aged 19 to 92 years. The subjects were divided into three groups by age： young adult （19-39 years）, middle-aged adult （40-59 years）, and the elderly （〉60 years）. The pulmonary function was measured with routine examination methods and 13 parameters including vital capacity （VC）, residual volume （RV）, functional residual capacity （FRC）, total lung capacity （TLC）, RV/TLC, forced vital capacity （FVC）, forced expiratory volume in one second （FEV1）, FEV1/FVC, peak expiratory flow （PEF）, forced expiratory flow at 25% of FVC exhaled （FEF25）, forced expiratory flow at 50% of FVC exhaled （FEF50）, diffusion capacity of the lung for carbon monoxide （DLCO）, and specific diffusion capacity of CO （KCO） were collected and analyzed. Changes in pulmonary function parameters among the influence on FEVJFVC and RV were studied further. Results Ten pulmonary function parameters including VC, FVC, pre-elderly and elderly subjects, especially the aging FEV1, FEV1/FVC, PEF, FEF25, FEF50, TLC, DLCO and KCO decreased significantly with age in both male and female subjects （P 〈0.01）. RV and RV/TLC were increased with age （P 〈0.01）. FRC remained stable during aging. Except FRC, the linear relationship was significant between age and other pulmonary function parameters. In the pre-elderly and elderly subjects, RV had a non-significantly increasing tendency with age （P 〉0.05）, and FEV1/FVC did not change significantly with age （P 〉0.05）. Conclusion Total pulmonary function was declined tendency of RV and decreasing tendency of FEV1/FVC with advancing age, but FRC was stable, and the increasing obviously slowed down in the pre-elderly and elderly subjects.
文摘Object detection is the most fundamental but challenging issues in the field of computer vision.Object detection identifies the presence of various individual objects in an image.Great success is attained for object detection/recognition problems in the controlled environment,but still,the problem remains unsolved in the uncontrolled places,particularly,when the objects are placed in arbitrary poses in an occluded and cluttered environment.In the last few years,a lots of efforts are made by researchers to resolve this issue,because of its wide range of applications in computer vision tasks,like content-enabled image retrieval,event or activity recognition,scene understanding,and so on.This review provides a detailed survey of 50 research papers presenting the object detection techniques,like machine learning-based techniques,gradient-based techniques,Fast Region-based Convolutional Neural Network(Fast R-CNN)detector,and the foreground-based techniques.Here,the machine learning-based approaches are classified into deep learning-based approaches,random forest,Support Vector Machine(SVM),and so on.Moreover,the challenges faced by the existing techniques are explained in the gaps and issues section.The analysis based on the classification,toolset,datasets utilized,published year,and the performance metrics are discussed.The future dimension of the research is based on the gaps and issues identified from the existing research works.
文摘People love mountains and waters, taking delight in talking about landscape. Some draw landscape paintings because they like mountains and waters, placing love on forests and springs.However, drawing mountains-and-waters paintings is no easy job, just like climbing mountains, which requires painters to learn from ancient prominent personage and walk a thousand li without any falsity and trickery.
