The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding...The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages.展开更多
Spike development directly affects the yield and quality of rice. We describe an algorithm for automatically identifying multiple developmental stages of rice spikes(AI-MDSRS) that transforms the automatic identificat...Spike development directly affects the yield and quality of rice. We describe an algorithm for automatically identifying multiple developmental stages of rice spikes(AI-MDSRS) that transforms the automatic identification of multiple developmental stages of rice spikes into the detection of rice spikes of diverse maturity levels. The scales vary greatly in different growth and development stages because rice spikes are dense and small, posing challenges for their effective and accurate detection. We describe a rice spike detection model based on an improved faster regions with convolutional neural network(Faster R-CNN).The model incorporates the following optimization strategies: first, Inception_Res Net-v2 replaces VGG16 as a feature extraction network;second, a feature pyramid network(FPN) replaces single-scale feature maps to fuse with region proposal network(RPN);third, region of interest(Ro I) alignment replaces Ro I pooling, and distance-intersection over union(DIo U) is used as a standard for non-maximum suppression(NMS). The performance of the proposed model was compared with that of the original Faster R-CNN and YOLOv4 models. The mean average precision(m AP) of the rice spike detection model was92.47%, a substantial improvement on the original Faster R-CNN model(with 40.96% m AP) and 3.4%higher than that of the YOLOv4 model, experimentally indicating that the model is more accurate and reliable. The identification results of the model for the heading–flowering, milky maturity, and full maturity stages were within two days of the results of manual observation, fully meeting the needs of agricultural activities.展开更多
The purpose of this article is twofold.First,it explores the order of the development of nominal and verbal gender of Amharic,which is one of the Ethio-Semitic languages.Second,it provides empirical evidence for the t...The purpose of this article is twofold.First,it explores the order of the development of nominal and verbal gender of Amharic,which is one of the Ethio-Semitic languages.Second,it provides empirical evidence for the typological plausibility of processability theory(PT).In fact,PT has been tested in typologically different languages(e.g.,English,Italian,and Japan);however,it does not have any validation from Ethiopian languages in general and Ethio-Semitic languages in particular yet.Relevant data was collected from sixteen respondents via picture description tasks,short storytelling,interviews,story re-telling,and spot the difference tasks.Distributional analysis was conducted for the analysis,and the point of emergence of target structures was determined using the emergence criteria.Accordingly,the result shows that the development of gender assignment is compatible with processability theory’s predictions in that lexical procedure precedes phrasal procedure,which is followed by S-procedure.Moreover,the masculine gender emerged earlier than its feminine counterpart at all developmental stages.However,subject agreement markers in pro-drop context emerged at stage two preceding subject verb agreement.This finding is against processability theory’s claim that suggests subject agreement markers only emerge at stage four of the processability hierarchy disregarding their stages of development in pro-drop context in particular.展开更多
The continuous growth of recoverable reserves in a waterflooding oilfield has a significant impact on the patterns of production evolution. A new production evolution model is established by improving the Weng Cycle m...The continuous growth of recoverable reserves in a waterflooding oilfield has a significant impact on the patterns of production evolution. A new production evolution model is established by improving the Weng Cycle model. With the new model, the statistical correspondence between the production decline stage and the reserve-production imbalance is clarified,and the correlation of water cut with the recovery percent of recoverable reserves is discussed, providing quantitative basis of reservoir engineering for dividing development stages of oilfield and defining mature oilfields. According to the statistics of oilfields in eastern China, the time point corresponding to the reserve-production balance coefficient dropping to less than 1dramatically is well correlated the beginning point of production decline, thus the time when the reserve-production balance coefficient drops dramatically can be taken as the initiation point of production decline stage. The research results show that the water cut and the recovery percent of recoverable reserves have a good statistical match in the high water cut stage, and it is more rational to take both the start point of production decline stage and the water cut of 90%(or the recovery percent of recoverable reserves of 80%) as the critical criteria for defining a mature oilfield. Five production evolution patterns can be summarized as follows: growth–peak plateau–stepped decline, growth–stepped stabilizing–stepped decline, growth–stepped stabilizing–rapid decline, growth–peak plateau–rapid decline, and growth–continuous decline.展开更多
Methanotrophs,organisms that obtain oxygen by oxidizing methane,are recognized as the only known biological sink for atmospheric CH_4,and forest soil methanotrophs play crucial roles in mitigating global warming.The s...Methanotrophs,organisms that obtain oxygen by oxidizing methane,are recognized as the only known biological sink for atmospheric CH_4,and forest soil methanotrophs play crucial roles in mitigating global warming.The succession patterns of methanotrophic communities and functions in Wudalianchi volcano forest soils could provide a basis for the study of evolutionary mechanisms between soil microorganisms,the environment,and carbon cycling of temperate forest ecosystems under climate change.In this study,the characteristics and drivers of methanotrophic community structure and function of two volcanic soils at different stages of development are analyzed,including an old volcano and a new volcano,which most recently erupted 300 years and 17-19×10^(5)years ago,respectively,and a non-volcano hills as control,based on space for time substitution and Miseq sequencing and bioinformation technology.The results showed that CH_(4) fluxes were significantly higher in old-stage volcano forest soils than new-stage forest soils and non-volcano forest soils.There were significant differences in the community composition and diversity of soil methanotrophs from different volcano forest soils.Methylococcus was the dominant genus in all soil samples.Additionally,the relative abundance of Methylococcus,along with Clonothrix,Methyloglobulus,Methylomagum,Methylomonas and Methylosarcina,were the important genera responsible for the differences in methanotrophic community structure in different volcano forest soils.The relative abundance of methanotroph belonging toγ-proteobacteria was significantly higher than that belonging toα-proteobacteria(P<0.05).Chao1,Shannon and Simpson indices of soil methanotrophic community were significantly lower in new-stage volcanos and were significantly affected by bulk density,total porosity,p H,nitrate,dissolved organic carbon and dissolved organic nitrogen.There were significant differences in community structure between new-stage and old-stage volcanoes.Bulk density and p H are important soil properties contributing to the divergence of methanotrophs community structure,and changes in soil properties due to soil development time are important factors driving differences in methanotrophs communities in Wudalianchi volcanic soils.展开更多
Xianning City of Hubei Province is one of the five major traditional osmanthus producing areas in the world and the hometown of osmanthus in China. Xianning is constructing China Osmanthus City in the whole city. This...Xianning City of Hubei Province is one of the five major traditional osmanthus producing areas in the world and the hometown of osmanthus in China. Xianning is constructing China Osmanthus City in the whole city. This paper first introduces the main characteristics of the osmanthus industry in Xianning City, and analyzes the characteristics of traditional knowledge, biological genetic resources, new plant varieties, patents, geographical indications, and trademarks. Then, it studies the intellectual property resources of the osmanthus industry, and analyzes the main problems existing in the construction of China Osmanthus City and intellectual property right protection. Finally, it comes up with constructive recommendations including applying for China and Globally Important Agricultural Heritage Systems, developing colored-leaf osmanthus varieties, creating a regional public brand of osmanthus specialty products, and building a new development pattern of osmanthus industry.展开更多
Agriculture is a basic industry related to national economy and people’s livelihood,and is also the cornerstone of national economic development. European Union(EU) is the second largest exporter of agricultural prod...Agriculture is a basic industry related to national economy and people’s livelihood,and is also the cornerstone of national economic development. European Union(EU) is the second largest exporter of agricultural products in the world,and its agricultural production change has international influence. In this paper,starting from two angles of EU agricultural development scale and target,development stage of its agricultural production is explored,and development and evolution causes of EU agriculture are analyzed: efficiency and benefit targets cause change of EU agricultural management model; change of agricultural product supply-demand pattern leads the evolution of EU agricultural development idea; the reflection of agricultural development target impels the transformation of EU agricultural development. On this basis,the below conclusions are obtained: agricultural development could evolve according to the changes of economic and social conditions; it is a necessary requirement of promoting internal market stability and international market harmony to actively use agricultural support policies adapting to agricultural development at each stage; it is an important measurement of impelling agricultural modernization process to promote innovation of agricultural management model and development of market integration; it is an inevitable road of realizing sustainable development of agriculture to develop ecological agriculture and emphasize equal development of agriculture and countryside. On this basis,it could provide the reference for agricultural development of China based on EU agricultural development experience.展开更多
This paper constructs the index system of the regional division of the development stage of China's wind power resources,including the index of energy,the index of wind energy endowments and other indices.Based on...This paper constructs the index system of the regional division of the development stage of China's wind power resources,including the index of energy,the index of wind energy endowments and other indices.Based on principal component analysis and layered clustering analysis of these indices,and combined with the conceptual function of the development and utilization stage of the wind power,this paper divides the development and utilization stage of the wind power into four stages taking province as the basic yardstick:optimization growth stage,the rapid growth stage,the slow growth stage and the initial growth stage.In addition,this paper briefly discusses the basic strategy that should be adopted in each development stage of wind power resources.展开更多
BACKGROUND: Under the normal circumstance, there exist some synapses with inactive functions in central nervous system (CNS), but these functions are activated following nerve injury. At the early stage of brain injur...BACKGROUND: Under the normal circumstance, there exist some synapses with inactive functions in central nervous system (CNS), but these functions are activated following nerve injury. At the early stage of brain injury, the abnormal functions of brain are varied, and they have very strong plasticity and are corrected easily. OBJECTIVE: To observe the changes of neuronal morphology in hippocampal CA1 region and memory function in newborn rats with hypoxic-ischemic encephalopathy(HIE) from ischemia 6 hours to adult. DESIGN: Completely randomized grouping, controlled experiment. SETTING: Taian Health Center for Women and Children; Taishan Medical College. MATERIALS: Altogether 120 seven-day-old Wistar rats, of clean grade, were provided by the Experimental Animal Center, Shandong University of Traditional Chinese Medicine. Synaptophysin (SYN) polyclonal antibody was provided by Maixin Biological Company, Fuzhou. METHODS: This experiment was carried out in the Laboratory of Morphology, Taishan Medical College between October 2000 and December 2003. ① The newborn rats were randomly divided into 2 groups: model group and control group, 60 rats in each group. Five rats were chosen from each group at postoperative 6 hours, 24 hours, 72 hours, 7 days, 2 weeks and 3 weeks separately for immunohistochemical staining. Fifteen newborn rats were chosen from each group at postoperative 4 weeks and 2 months separately for testing memory ability (After test, 5 rats from each group were sacrificed and used for immunohistochemical staining)② The right common carotid artery of newborn rats of model group was ligated under the anesthetized status. After two hours of incubation, the rats were placed for 2 hours in a container filled with nitrogen oxygen atmosphere containing 0.08 volume fraction of oxygen, thus, HIE models were created; As for the newborn rats in the control group, only blood vessels were isolated, and they were not ligated and hypoxia-treated. ③ Thalamencephal tissue sections of newborn rats of two groups were performed DAB developing and haematoxylin slight staining. Cells with normal nucleous in 250 μm-long granular layer which started from hippocampal CA1 region were counted with image analysis system under high-fold optical microscope (×600), and the thickness of granular layer was measured. The absorbance (A) of positive reactant of SYN in immunohistochemically-stained CA1 region was measured. Learning and memory ability were measured with step through test 3 times successively. ④ t test and paired t test were used for comparing intergroup and intragroup difference of measurement data respectively, and Chi-square for comparing the difference of enumeration data. MAIN OUTCOME MEASURES: Comparison of cytological changes in hippocampal CA1 region and memory ability at different postoperative time points between two groups. RESULTS: Totally 120 newborn rats were involved in the result analysis. ① Cell morphological changes in hippocampal CA1 region: In the control group, with aging, perikaryon, nucleus and nucleolus in cortex of parietal lobe were significantly increased, Nissl body was compacted, the amount of neurons was declined, but the A of SYN positive reactant was relatively increased. In the model group, at postoperative each time point, neurons were seriously shrunk and dark-stained, nucleus was contracted, chromatin was condensed, nucleolus was unclear, even cells disappeared, especially the cells in 6 hours and 24 hours groups. The amount of neurons with normal morphology in hippocampal CA1 region and granular layer thickness in the model group at postoperative each time point were significantly less or smaller than those in the control group at postoperative 6 hours respectively (t =3.002-1.254, P < 0.01). The A value of SYN positive reactant at postoperative 2, 3 and 4 weeks was significantly higher than that at previous time point (t =2.011-2.716,P < 0.05-0.01). ② Test results of learning and memory ability: In the first test, there was no significant difference in the ratio of rats which kept memory ability between two groups (P > 0.05); In the third test, the ratio of rats which kept memory ability in the model group was significantly lower than that in the control group at postoperative 4 weeks and 2 months[53%(8/15),100%(15/15);60%(9/15),93%(14/15),χ 2=2.863,2.901,P < 0.01]. CONCLUSION: The destroyed hippocampal structure induces the decrease of learning and memory ability of developmental rats. Early interference can increase the quality of neurons and also promote functional development of the nervous system.展开更多
the pursuit of the liberation of all mankind and the comprehensive development of human freedom is the theme of all marxist theories.Marx in the criticism of classical political economics“abstract”,to the whole hist...the pursuit of the liberation of all mankind and the comprehensive development of human freedom is the theme of all marxist theories.Marx in the criticism of classical political economics“abstract”,to the whole history of the definition of“general”,found the abstract“general”of the people behind the objective existence and state of development,so as to clearly indicate the relationship between man and nature of human development has experienced on the basis of the nature of the dependence on one stage,gradually from natural objects depends on the stage and with the natural fusion of freedom comprehensive stage,and the concrete connotation of man’s free overall and implementation path.展开更多
As China entered into a new era of development, the primary contradiction facing Chinese society has also evolved. It is important for both scholars and policymakers to review the characteristics of China's econom...As China entered into a new era of development, the primary contradiction facing Chinese society has also evolved. It is important for both scholars and policymakers to review the characteristics of China's economy in its present stage in accordance with economic principles-principles that reflect every aspect of economic and social life and macroeconomic regulation. In this paper, we attempt to unravel the characteristics of China's new era from three perspectives-historical materialism, dialectic materialism and epistemology, and in light of economic principles at the three levels of resource factors, modes of production and regulation of resource allocation. Based on these perspectives, this paper further identifies the characteristics of China's new era from nine aspects, including globalization, modernization, the primary stage of socialism, new development concepts, supply-side reforms, the guideline of seeking steady progress, the mentality of scope, bottomline mindset and strategic composure. From the three different levels, this paper summarizes and applies economic principles to propose solutions to the problems and challenges facing China in the new era. The findings of the paper are also relevant to implementation of the guidelines CPC Central Committee General Secretary Xi Jinping noted in his report to the 19 th CPC National Congress.展开更多
The economic and technological development zones (ETDZ) in China began their 11th year in 1995. Since 1984 the State Council has approved 32 ETDZs. In the past few years the ETDZs have gained remarkable achievements i...The economic and technological development zones (ETDZ) in China began their 11th year in 1995. Since 1984 the State Council has approved 32 ETDZs. In the past few years the ETDZs have gained remarkable achievements in improving the investment climate, raising the management and service level and attracting foreign funds. The economic benefits have had a simultaneous develonment in the first 14 ETDZs in展开更多
1. Review of railway work in 1996 The year 1996 was an important year for China’s railways in facing a historic turning point—— committing itself to a programme of structural re-
As a major developing country,China has attracted significant attention as to whichpathitshouldfol owfortechnologicalprogress.Accordingtotheauthorofthispaper,Chinashouldcontinueto pursue the international division of ...As a major developing country,China has attracted significant attention as to whichpathitshouldfol owfortechnologicalprogress.Accordingtotheauthorofthispaper,Chinashouldcontinueto pursue the international division of labor and competition strategy based on comparative advantages.Meanwhile,China should,through reform and adjustment,build a national innovation system capable ofplaying an e ective role in the future.However,laying too much emphasis on proprietary innovation atthe present stage wil bring about undesirable consequences.The timing for China to embark on a path oftechnologicaldevelopmentthroughproprietaryinnovationissubjecttothechangesbothintradeconditionsandin income distribution e ects arising from proprietary innovation.展开更多
The system planning of the Northwest China 330 kV Power System from present to the year 2000 is introduced in this paper. Some technical problems arising from the system planning, such as network configuration, system...The system planning of the Northwest China 330 kV Power System from present to the year 2000 is introduced in this paper. Some technical problems arising from the system planning, such as network configuration, system stability and reactive power compensation etc. are also briefly summarized.展开更多
This paper systematically reviews the trend of carbon dioxide capture,utilization and storage(CCUS)industry in the world and China,presents the CCUS projects,clusters,technologies and strategies/policies,and analyzes ...This paper systematically reviews the trend of carbon dioxide capture,utilization and storage(CCUS)industry in the world and China,presents the CCUS projects,clusters,technologies and strategies/policies,and analyzes the CCUS challenges and countermeasures in China based on the comparison of CCUS industrial development at home and abroad.The global CCUS development has experienced three stages:exploration stage,policy driven stage,and dual-drive stage.Currently,the active large-scale CCUS projects around the world focus on enhanced oil recovery(EOR)and are expanding into storage in saline aquifers.The CCUS industry of China has evolved in three stages:exploration,pilot test,and industrialization.In the current critical period of transition from field test to industrialization,China’s CCUS projects are EOR-dominated.By comparing the industrial development of CCUS in China and abroad,it is found that the scale-up and industrialization of CCUS in China face challenges in technology,facilities and policies.Finally,future solutions to CCUS development in China are proposed as follows:strengthening the top-level design and planning of CCUS;developing high-efficiency and low-cost CCUS technologies throughout the whole industrial chain;deploying CCUS oil and gas+new energy clusters;improving the policy support system of CCUS;and strengthening discipline construction and personnel training,etc.展开更多
Soil microbial biomass carbon (MBC), β-glucosidase, acid phosphatase and fluorescein diacetate (FDA) activities and bacterial community structure were assessed in a long-term (26 years) experiment, at physiological s...Soil microbial biomass carbon (MBC), β-glucosidase, acid phosphatase and fluorescein diacetate (FDA) activities and bacterial community structure were assessed in a long-term (26 years) experiment, at physiological stages of sorghum growth, comparing different management methods for organic (manure, straw residues) and inorganic (urea) amendments at the INERA field station in Saria (Burkina Faso). Annual application of manure led to the highest soil microbial biomass and enzyme activities. Investigations indicated that only microbial biomass and β-glucosidase activities were affected during the cropping season. Phosphatase and FDA enzyme activities did not depend on the crop development stages. The application of N fertilizer modified phosphatase and FDA enzyme activities, the activities being higher in soils amended with N fertilizer. The bacterial community structure was analyzed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the eubacterial 16S rRNA gene. Cluster analysis of PCR-DGGE patterns showed two major clusters, the first containing the mineral fertilization and straw treatments and the second, the straw + urea, manure and manure + urea treatments. Sorghum grain yields were the highest for manure treatments. In this long-term experiment, applying straw did not produce a better grain yield than that obtained in the un-amended plot.展开更多
Objective The Guanzhong Plain of Shaanxi Province is a severely afflicted hemorrhagic fever with renal syndrome(HFRS)epidemic area,while HFRS prevalence has decreased in most epidemic areas in China.Little information...Objective The Guanzhong Plain of Shaanxi Province is a severely afflicted hemorrhagic fever with renal syndrome(HFRS)epidemic area,while HFRS prevalence has decreased in most epidemic areas in China.Little information is available regarding the leading fine-scale influencing factors in this highly HFRSconcentrated area and the roles of natural environmental and socioeconomic factors.To investigate this,two regions in the Guanzhong Plain,that is,the Chang’an District and Hu County,with similar geographical environments,different levels of economic development,and high epidemic prevalence,were chosen as representative areas of the HFRS epidemic.Methods Maximum entropy models were constructed based on HFRS cases and fine-scale influencing factors,including meteorological,natural environmental,and socioeconomic factors,from 2014 to 2016.Results More than 95% of the HFRS cases in the study area were located in the northern plains,which has an altitude of less than 800 m,with topography contributed 84.1% of the impact on the spatial differentiation of the HFRS epidemic.In the northern plains,precipitation and population density jointly affected the spatial differentiation of the HFRS epidemic,with contribution rates of 60.7% and 28.0%,respectively.By comparing the influencing factors of the northern plains of Chang’an District and Hu County,we found that precipitation and the normalized difference vegetation index(NDVI)dominated the HFRS epidemic in the relatively developed Chang’an District,while land-use type,temperature,precipitation and population density dominated the HFRS epidemic in the relatively undeveloped Hu County.Conclusion Topography was the primary key factor for HFRS prevalence in the Chang’an District and Hu County,and the spatial differentiation of HFRS was dominated by precipitation and population density in the northern plains.Compared with the influencing factors of the relatively developed Chang’an District,the developing Hu County was more affected by socioeconomic factors.When formulating targeted HFRS epidemic prevention and control strategies in the targeted areas,it is crucial to consider the local economic development state and combine natural environmental factors,including the meteorological environment and vegetation coverage.展开更多
基金supported by the National Natural Science Foundation of China(31790410,32160781)。
文摘The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages.
基金supported by the Key-Area Research and Development Program of Guangdong Province (2019B020214005)Agricultural Research Project and Agricultural Technology Promotion Project of Guangdong (2021KJ383)。
文摘Spike development directly affects the yield and quality of rice. We describe an algorithm for automatically identifying multiple developmental stages of rice spikes(AI-MDSRS) that transforms the automatic identification of multiple developmental stages of rice spikes into the detection of rice spikes of diverse maturity levels. The scales vary greatly in different growth and development stages because rice spikes are dense and small, posing challenges for their effective and accurate detection. We describe a rice spike detection model based on an improved faster regions with convolutional neural network(Faster R-CNN).The model incorporates the following optimization strategies: first, Inception_Res Net-v2 replaces VGG16 as a feature extraction network;second, a feature pyramid network(FPN) replaces single-scale feature maps to fuse with region proposal network(RPN);third, region of interest(Ro I) alignment replaces Ro I pooling, and distance-intersection over union(DIo U) is used as a standard for non-maximum suppression(NMS). The performance of the proposed model was compared with that of the original Faster R-CNN and YOLOv4 models. The mean average precision(m AP) of the rice spike detection model was92.47%, a substantial improvement on the original Faster R-CNN model(with 40.96% m AP) and 3.4%higher than that of the YOLOv4 model, experimentally indicating that the model is more accurate and reliable. The identification results of the model for the heading–flowering, milky maturity, and full maturity stages were within two days of the results of manual observation, fully meeting the needs of agricultural activities.
文摘The purpose of this article is twofold.First,it explores the order of the development of nominal and verbal gender of Amharic,which is one of the Ethio-Semitic languages.Second,it provides empirical evidence for the typological plausibility of processability theory(PT).In fact,PT has been tested in typologically different languages(e.g.,English,Italian,and Japan);however,it does not have any validation from Ethiopian languages in general and Ethio-Semitic languages in particular yet.Relevant data was collected from sixteen respondents via picture description tasks,short storytelling,interviews,story re-telling,and spot the difference tasks.Distributional analysis was conducted for the analysis,and the point of emergence of target structures was determined using the emergence criteria.Accordingly,the result shows that the development of gender assignment is compatible with processability theory’s predictions in that lexical procedure precedes phrasal procedure,which is followed by S-procedure.Moreover,the masculine gender emerged earlier than its feminine counterpart at all developmental stages.However,subject agreement markers in pro-drop context emerged at stage two preceding subject verb agreement.This finding is against processability theory’s claim that suggests subject agreement markers only emerge at stage four of the processability hierarchy disregarding their stages of development in pro-drop context in particular.
基金Supported by the National Natural Science Foundation of China (72088101)。
文摘The continuous growth of recoverable reserves in a waterflooding oilfield has a significant impact on the patterns of production evolution. A new production evolution model is established by improving the Weng Cycle model. With the new model, the statistical correspondence between the production decline stage and the reserve-production imbalance is clarified,and the correlation of water cut with the recovery percent of recoverable reserves is discussed, providing quantitative basis of reservoir engineering for dividing development stages of oilfield and defining mature oilfields. According to the statistics of oilfields in eastern China, the time point corresponding to the reserve-production balance coefficient dropping to less than 1dramatically is well correlated the beginning point of production decline, thus the time when the reserve-production balance coefficient drops dramatically can be taken as the initiation point of production decline stage. The research results show that the water cut and the recovery percent of recoverable reserves have a good statistical match in the high water cut stage, and it is more rational to take both the start point of production decline stage and the water cut of 90%(or the recovery percent of recoverable reserves of 80%) as the critical criteria for defining a mature oilfield. Five production evolution patterns can be summarized as follows: growth–peak plateau–stepped decline, growth–stepped stabilizing–stepped decline, growth–stepped stabilizing–rapid decline, growth–peak plateau–rapid decline, and growth–continuous decline.
基金the Special Projects for the Central Government to guide the development of local science and technology(ZY20B15)the Key Research&Development Program funding project of Heilongjiang Province(GA21C030)the Research Funds of Provincial Research Institutes of Heilongjiang Province(ZNBZ2022ZR07)。
文摘Methanotrophs,organisms that obtain oxygen by oxidizing methane,are recognized as the only known biological sink for atmospheric CH_4,and forest soil methanotrophs play crucial roles in mitigating global warming.The succession patterns of methanotrophic communities and functions in Wudalianchi volcano forest soils could provide a basis for the study of evolutionary mechanisms between soil microorganisms,the environment,and carbon cycling of temperate forest ecosystems under climate change.In this study,the characteristics and drivers of methanotrophic community structure and function of two volcanic soils at different stages of development are analyzed,including an old volcano and a new volcano,which most recently erupted 300 years and 17-19×10^(5)years ago,respectively,and a non-volcano hills as control,based on space for time substitution and Miseq sequencing and bioinformation technology.The results showed that CH_(4) fluxes were significantly higher in old-stage volcano forest soils than new-stage forest soils and non-volcano forest soils.There were significant differences in the community composition and diversity of soil methanotrophs from different volcano forest soils.Methylococcus was the dominant genus in all soil samples.Additionally,the relative abundance of Methylococcus,along with Clonothrix,Methyloglobulus,Methylomagum,Methylomonas and Methylosarcina,were the important genera responsible for the differences in methanotrophic community structure in different volcano forest soils.The relative abundance of methanotroph belonging toγ-proteobacteria was significantly higher than that belonging toα-proteobacteria(P<0.05).Chao1,Shannon and Simpson indices of soil methanotrophic community were significantly lower in new-stage volcanos and were significantly affected by bulk density,total porosity,p H,nitrate,dissolved organic carbon and dissolved organic nitrogen.There were significant differences in community structure between new-stage and old-stage volcanoes.Bulk density and p H are important soil properties contributing to the divergence of methanotrophs community structure,and changes in soil properties due to soil development time are important factors driving differences in methanotrophs communities in Wudalianchi volcanic soils.
基金Supported by Special Soft Science Research Project for Hubei Province Science and Technology Innovation Talents and Services (2022EDA060)。
文摘Xianning City of Hubei Province is one of the five major traditional osmanthus producing areas in the world and the hometown of osmanthus in China. Xianning is constructing China Osmanthus City in the whole city. This paper first introduces the main characteristics of the osmanthus industry in Xianning City, and analyzes the characteristics of traditional knowledge, biological genetic resources, new plant varieties, patents, geographical indications, and trademarks. Then, it studies the intellectual property resources of the osmanthus industry, and analyzes the main problems existing in the construction of China Osmanthus City and intellectual property right protection. Finally, it comes up with constructive recommendations including applying for China and Globally Important Agricultural Heritage Systems, developing colored-leaf osmanthus varieties, creating a regional public brand of osmanthus specialty products, and building a new development pattern of osmanthus industry.
文摘Agriculture is a basic industry related to national economy and people’s livelihood,and is also the cornerstone of national economic development. European Union(EU) is the second largest exporter of agricultural products in the world,and its agricultural production change has international influence. In this paper,starting from two angles of EU agricultural development scale and target,development stage of its agricultural production is explored,and development and evolution causes of EU agriculture are analyzed: efficiency and benefit targets cause change of EU agricultural management model; change of agricultural product supply-demand pattern leads the evolution of EU agricultural development idea; the reflection of agricultural development target impels the transformation of EU agricultural development. On this basis,the below conclusions are obtained: agricultural development could evolve according to the changes of economic and social conditions; it is a necessary requirement of promoting internal market stability and international market harmony to actively use agricultural support policies adapting to agricultural development at each stage; it is an important measurement of impelling agricultural modernization process to promote innovation of agricultural management model and development of market integration; it is an inevitable road of realizing sustainable development of agriculture to develop ecological agriculture and emphasize equal development of agriculture and countryside. On this basis,it could provide the reference for agricultural development of China based on EU agricultural development experience.
基金National Basic Research and Development Program(973)(Grant no.2007CB210306)
文摘This paper constructs the index system of the regional division of the development stage of China's wind power resources,including the index of energy,the index of wind energy endowments and other indices.Based on principal component analysis and layered clustering analysis of these indices,and combined with the conceptual function of the development and utilization stage of the wind power,this paper divides the development and utilization stage of the wind power into four stages taking province as the basic yardstick:optimization growth stage,the rapid growth stage,the slow growth stage and the initial growth stage.In addition,this paper briefly discusses the basic strategy that should be adopted in each development stage of wind power resources.
基金the Grant from Family Planning Commission of Shandong Province,No.97-15
文摘BACKGROUND: Under the normal circumstance, there exist some synapses with inactive functions in central nervous system (CNS), but these functions are activated following nerve injury. At the early stage of brain injury, the abnormal functions of brain are varied, and they have very strong plasticity and are corrected easily. OBJECTIVE: To observe the changes of neuronal morphology in hippocampal CA1 region and memory function in newborn rats with hypoxic-ischemic encephalopathy(HIE) from ischemia 6 hours to adult. DESIGN: Completely randomized grouping, controlled experiment. SETTING: Taian Health Center for Women and Children; Taishan Medical College. MATERIALS: Altogether 120 seven-day-old Wistar rats, of clean grade, were provided by the Experimental Animal Center, Shandong University of Traditional Chinese Medicine. Synaptophysin (SYN) polyclonal antibody was provided by Maixin Biological Company, Fuzhou. METHODS: This experiment was carried out in the Laboratory of Morphology, Taishan Medical College between October 2000 and December 2003. ① The newborn rats were randomly divided into 2 groups: model group and control group, 60 rats in each group. Five rats were chosen from each group at postoperative 6 hours, 24 hours, 72 hours, 7 days, 2 weeks and 3 weeks separately for immunohistochemical staining. Fifteen newborn rats were chosen from each group at postoperative 4 weeks and 2 months separately for testing memory ability (After test, 5 rats from each group were sacrificed and used for immunohistochemical staining)② The right common carotid artery of newborn rats of model group was ligated under the anesthetized status. After two hours of incubation, the rats were placed for 2 hours in a container filled with nitrogen oxygen atmosphere containing 0.08 volume fraction of oxygen, thus, HIE models were created; As for the newborn rats in the control group, only blood vessels were isolated, and they were not ligated and hypoxia-treated. ③ Thalamencephal tissue sections of newborn rats of two groups were performed DAB developing and haematoxylin slight staining. Cells with normal nucleous in 250 μm-long granular layer which started from hippocampal CA1 region were counted with image analysis system under high-fold optical microscope (×600), and the thickness of granular layer was measured. The absorbance (A) of positive reactant of SYN in immunohistochemically-stained CA1 region was measured. Learning and memory ability were measured with step through test 3 times successively. ④ t test and paired t test were used for comparing intergroup and intragroup difference of measurement data respectively, and Chi-square for comparing the difference of enumeration data. MAIN OUTCOME MEASURES: Comparison of cytological changes in hippocampal CA1 region and memory ability at different postoperative time points between two groups. RESULTS: Totally 120 newborn rats were involved in the result analysis. ① Cell morphological changes in hippocampal CA1 region: In the control group, with aging, perikaryon, nucleus and nucleolus in cortex of parietal lobe were significantly increased, Nissl body was compacted, the amount of neurons was declined, but the A of SYN positive reactant was relatively increased. In the model group, at postoperative each time point, neurons were seriously shrunk and dark-stained, nucleus was contracted, chromatin was condensed, nucleolus was unclear, even cells disappeared, especially the cells in 6 hours and 24 hours groups. The amount of neurons with normal morphology in hippocampal CA1 region and granular layer thickness in the model group at postoperative each time point were significantly less or smaller than those in the control group at postoperative 6 hours respectively (t =3.002-1.254, P < 0.01). The A value of SYN positive reactant at postoperative 2, 3 and 4 weeks was significantly higher than that at previous time point (t =2.011-2.716,P < 0.05-0.01). ② Test results of learning and memory ability: In the first test, there was no significant difference in the ratio of rats which kept memory ability between two groups (P > 0.05); In the third test, the ratio of rats which kept memory ability in the model group was significantly lower than that in the control group at postoperative 4 weeks and 2 months[53%(8/15),100%(15/15);60%(9/15),93%(14/15),χ 2=2.863,2.901,P < 0.01]. CONCLUSION: The destroyed hippocampal structure induces the decrease of learning and memory ability of developmental rats. Early interference can increase the quality of neurons and also promote functional development of the nervous system.
文摘the pursuit of the liberation of all mankind and the comprehensive development of human freedom is the theme of all marxist theories.Marx in the criticism of classical political economics“abstract”,to the whole history of the definition of“general”,found the abstract“general”of the people behind the objective existence and state of development,so as to clearly indicate the relationship between man and nature of human development has experienced on the basis of the nature of the dependence on one stage,gradually from natural objects depends on the stage and with the natural fusion of freedom comprehensive stage,and the concrete connotation of man’s free overall and implementation path.
文摘As China entered into a new era of development, the primary contradiction facing Chinese society has also evolved. It is important for both scholars and policymakers to review the characteristics of China's economy in its present stage in accordance with economic principles-principles that reflect every aspect of economic and social life and macroeconomic regulation. In this paper, we attempt to unravel the characteristics of China's new era from three perspectives-historical materialism, dialectic materialism and epistemology, and in light of economic principles at the three levels of resource factors, modes of production and regulation of resource allocation. Based on these perspectives, this paper further identifies the characteristics of China's new era from nine aspects, including globalization, modernization, the primary stage of socialism, new development concepts, supply-side reforms, the guideline of seeking steady progress, the mentality of scope, bottomline mindset and strategic composure. From the three different levels, this paper summarizes and applies economic principles to propose solutions to the problems and challenges facing China in the new era. The findings of the paper are also relevant to implementation of the guidelines CPC Central Committee General Secretary Xi Jinping noted in his report to the 19 th CPC National Congress.
文摘The economic and technological development zones (ETDZ) in China began their 11th year in 1995. Since 1984 the State Council has approved 32 ETDZs. In the past few years the ETDZs have gained remarkable achievements in improving the investment climate, raising the management and service level and attracting foreign funds. The economic benefits have had a simultaneous develonment in the first 14 ETDZs in
文摘1. Review of railway work in 1996 The year 1996 was an important year for China’s railways in facing a historic turning point—— committing itself to a programme of structural re-
文摘As a major developing country,China has attracted significant attention as to whichpathitshouldfol owfortechnologicalprogress.Accordingtotheauthorofthispaper,Chinashouldcontinueto pursue the international division of labor and competition strategy based on comparative advantages.Meanwhile,China should,through reform and adjustment,build a national innovation system capable ofplaying an e ective role in the future.However,laying too much emphasis on proprietary innovation atthe present stage wil bring about undesirable consequences.The timing for China to embark on a path oftechnologicaldevelopmentthroughproprietaryinnovationissubjecttothechangesbothintradeconditionsandin income distribution e ects arising from proprietary innovation.
文摘The system planning of the Northwest China 330 kV Power System from present to the year 2000 is introduced in this paper. Some technical problems arising from the system planning, such as network configuration, system stability and reactive power compensation etc. are also briefly summarized.
基金Supported by the Petrochina Science and Technology Project(2021ZZ01).
文摘This paper systematically reviews the trend of carbon dioxide capture,utilization and storage(CCUS)industry in the world and China,presents the CCUS projects,clusters,technologies and strategies/policies,and analyzes the CCUS challenges and countermeasures in China based on the comparison of CCUS industrial development at home and abroad.The global CCUS development has experienced three stages:exploration stage,policy driven stage,and dual-drive stage.Currently,the active large-scale CCUS projects around the world focus on enhanced oil recovery(EOR)and are expanding into storage in saline aquifers.The CCUS industry of China has evolved in three stages:exploration,pilot test,and industrialization.In the current critical period of transition from field test to industrialization,China’s CCUS projects are EOR-dominated.By comparing the industrial development of CCUS in China and abroad,it is found that the scale-up and industrialization of CCUS in China face challenges in technology,facilities and policies.Finally,future solutions to CCUS development in China are proposed as follows:strengthening the top-level design and planning of CCUS;developing high-efficiency and low-cost CCUS technologies throughout the whole industrial chain;deploying CCUS oil and gas+new energy clusters;improving the policy support system of CCUS;and strengthening discipline construction and personnel training,etc.
文摘Soil microbial biomass carbon (MBC), β-glucosidase, acid phosphatase and fluorescein diacetate (FDA) activities and bacterial community structure were assessed in a long-term (26 years) experiment, at physiological stages of sorghum growth, comparing different management methods for organic (manure, straw residues) and inorganic (urea) amendments at the INERA field station in Saria (Burkina Faso). Annual application of manure led to the highest soil microbial biomass and enzyme activities. Investigations indicated that only microbial biomass and β-glucosidase activities were affected during the cropping season. Phosphatase and FDA enzyme activities did not depend on the crop development stages. The application of N fertilizer modified phosphatase and FDA enzyme activities, the activities being higher in soils amended with N fertilizer. The bacterial community structure was analyzed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the eubacterial 16S rRNA gene. Cluster analysis of PCR-DGGE patterns showed two major clusters, the first containing the mineral fertilization and straw treatments and the second, the straw + urea, manure and manure + urea treatments. Sorghum grain yields were the highest for manure treatments. In this long-term experiment, applying straw did not produce a better grain yield than that obtained in the un-amended plot.
基金funded by the National Natural Science Foundation of China[grant number 41901337 and 42071136]。
文摘Objective The Guanzhong Plain of Shaanxi Province is a severely afflicted hemorrhagic fever with renal syndrome(HFRS)epidemic area,while HFRS prevalence has decreased in most epidemic areas in China.Little information is available regarding the leading fine-scale influencing factors in this highly HFRSconcentrated area and the roles of natural environmental and socioeconomic factors.To investigate this,two regions in the Guanzhong Plain,that is,the Chang’an District and Hu County,with similar geographical environments,different levels of economic development,and high epidemic prevalence,were chosen as representative areas of the HFRS epidemic.Methods Maximum entropy models were constructed based on HFRS cases and fine-scale influencing factors,including meteorological,natural environmental,and socioeconomic factors,from 2014 to 2016.Results More than 95% of the HFRS cases in the study area were located in the northern plains,which has an altitude of less than 800 m,with topography contributed 84.1% of the impact on the spatial differentiation of the HFRS epidemic.In the northern plains,precipitation and population density jointly affected the spatial differentiation of the HFRS epidemic,with contribution rates of 60.7% and 28.0%,respectively.By comparing the influencing factors of the northern plains of Chang’an District and Hu County,we found that precipitation and the normalized difference vegetation index(NDVI)dominated the HFRS epidemic in the relatively developed Chang’an District,while land-use type,temperature,precipitation and population density dominated the HFRS epidemic in the relatively undeveloped Hu County.Conclusion Topography was the primary key factor for HFRS prevalence in the Chang’an District and Hu County,and the spatial differentiation of HFRS was dominated by precipitation and population density in the northern plains.Compared with the influencing factors of the relatively developed Chang’an District,the developing Hu County was more affected by socioeconomic factors.When formulating targeted HFRS epidemic prevention and control strategies in the targeted areas,it is crucial to consider the local economic development state and combine natural environmental factors,including the meteorological environment and vegetation coverage.
