The Wufeng–Longmaxi Formation derives its name from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation,found in sequence in the Sichuan Basin.This formation hosts rich shale gas reservoir...The Wufeng–Longmaxi Formation derives its name from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation,found in sequence in the Sichuan Basin.This formation hosts rich shale gas reservoirs,and its shale gas enrichment patterns are examined in this study using data from 1197 shale samples collected from 14 wells.Five basic and three key parameters,eight in all,are assessed for each sample.The five basic parameters include burial depth and the contents of four mineral types—quartz,clay,carbonate,and other minerals;the three key parameters,representing shale gas enrichment,are total organic carbon(TOC)content,porosity,and gas content.The SHapley Additive exPlanations(SHAP)analysis originated in game theory is used here in an interpretable machine learning framework,to address issues of heterogeneous data structure,noisy relationships,and multi-objective optimization.An evaluation of the ranking,contribution values,and conditions of changes for these parameters offers new quantitative insights into shale gas enrichment patterns.A quantitative analysis of the relationship between data-sets identifies the primary factors controlling TOC,porosity,and gas content of shale gas reservoirs.The results show that TOC and porosity jointly influence gas content;mineral content has a significant impact on both,TOC and porosity;and the burial depth governs porosity which,in turn,affects the conditions under which shale gas is preserved.Input parameter thresholds are also determined and provide a basis for the establishment of quantitative criteria to evaluate shale gas enrichment.The predictive accuracy of the model used in this study is significantly improved by the step-wise addition of two input parameters,namely TOC and porosity,separately and together.Thus,the game theory method in big data-driven analysis uses a combination of TOC and porosity to evaluate the gas content with encouraging results—suggesting that these are the key parameters that indicate source rock and reservoir properties.展开更多
Kinesins are a superfamily of proteins widely present in eukaryotes,playing crucial roles in plant cell wall assembly,cell elongation regulation,gravity sensing,and fertility control.In this study,bioinformatics analy...Kinesins are a superfamily of proteins widely present in eukaryotes,playing crucial roles in plant cell wall assembly,cell elongation regulation,gravity sensing,and fertility control.In this study,bioinformatics analysis of the OsKMP2 gene(LOC_Os02g28850)was performed using online tools such as ExPASy-ProtParam,ProtScale,CD-search,and DNAMAN software.Additionally,qRT-PCR was employed to analyze the tissue expression pattern of OsKMP2.The results showed that the molecular weight of the OsKMP2 is 118.39728 kDa,and it is a hydrophilic and unstable acidic protein.Secondary structure prediction revealed that it primarily consists ofα-helices(69.45%),random coils(25.19%),and extended strands(5.36%).The gene was expressed in various rice tissues,with the highest expression level observed in leaves.These results indicate that the OsKMP2 gene exhibits high evolutionary conservation and functional diversity in rice.展开更多
The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examinin...The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examining their phylogenetic relationships,conserved motifs,gene structures,and syntenic relationships.The analysis identified 54 Ah PR10 genes,which were classified into eight groups based on phylogenetic relationships,supported by gene structure and conserved motif characterization.Analysis of chromosomal distribution and synteny demonstrated that segmental duplications played a crucial role in the expansion of the Ah PR10 gene family.The identified Ah PR10 genes exhibited both constitutive and inducible expression patterns.Significantly,Ah PR10-7,Ah PR10-33,and Ah PR10-41 demonstrated potential importance in peanut resistance to Aspergillus flavus.In vitro fungistatic experiments demonstrated that recombinant Ah PR10-33 effectively inhibited A.flavus mycelial growth.These findings provide valuable insights for future investigations into Ah PR10 functions in protecting peanut from A.flavus infection.展开更多
Existing studies on the Regional Comprehensive Economic Partnership(RCEP)mainly focused on institutional features,macro-economic impacts,and trade-network structures,while its geographic attributes and their implicati...Existing studies on the Regional Comprehensive Economic Partnership(RCEP)mainly focused on institutional features,macro-economic impacts,and trade-network structures,while its geographic attributes and their implications remain underexplored.Taking the RCEP as a case,this paper examines how the FTA reshapes China’s trade geography and validates these effects with an enhanced GTAP model,providing an empirical basis for advancing trade-geography theory.Key findings include:(1)RCEP significantly reduces regional trade costs.After full implementation of the agreement,the average tariffs among member countries will decrease to 40.5%of the pre-implementation level,while import and export trade facilitation levels improve by 34.3%and 29.6%,respectively.However,these improvements exhibit marked regional disparities.(2)RCEP asymmetrically promotes China’s foreign trade growth,with stronger import stimulation than export expansion,alongside significant product-specific variations.(3)The agreement reshapes China’s trade geography,driving a 7.66%increase in intra-RCEP trade while reducing extra-RCEP trade by 0.80%.(4)The restructuring of China’s trade patterns under RCEP emerges from the complex interplay of trade creation,diversion,and crowding-out effects.Accordingly,China should further harmonize regional tariff schedules,enhance trade-facilitation mechanisms,strengthen industrial competitiveness and expand multilateral partnerships.展开更多
In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purpos...In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purposes by applying three methods： the support vector machine （SVM） model, the radial basis function neural network （RBFNN） model and the multinomial logit （MNL） model. The effect of explanatory factors on trip chaining behaviors and their contribution to model performace were investigated by sensitivity analysis. Results show that the SVM model has a better performance than the RBFNN model and the MNL model due to its higher overall and partial accuracy, indicating its recognition advantage under a smai sample size scenario. It is also proved that the SVM model is capable of estimating the effect of multi-category factors on trip chaining behaviors more accurately. The different contribution of explanatory, factors to trip chaining pattern recognition reflects the importance of refining trip chaining patterns ad exploring factors that are specific to each pattern. It is shown that the SVM technology in travel demand forecast modeling and analysis of explanatory variable effects is practical.展开更多
Based on the land use status map of Shihezi City,the land use landscape map of Shihezi City was made with the support of GIS then many landscape indices were selected to quantitatively analyze the landscape pattern ch...Based on the land use status map of Shihezi City,the land use landscape map of Shihezi City was made with the support of GIS then many landscape indices were selected to quantitatively analyze the landscape pattern characteristics of Shihezi Oasis from three aspects of landscape diversity index,landscape space configuration index and plaque characteristics index. The results showed that the main plaque types of the landscape in Shihezi reclamation area are arable land and water areas,which totally account for 58% of the total area; farmland,gardens,woodland,urban sites,industrial and mining land use were embedded in this oasis landscape in the form of mosaics,and their fractal index was high due to the strong impact of human activities; arable land and mining land distribution was scattered,but marshes and other uncultivated land were relatively concentrated. The dominance degree of the landscape was low because there was no advantageous type in this landscape and all patches distributed equably which was easily to be disturbed so that the whole landscape was unstable. Comprehensively speaking,the landscape in Shihezi region was rather complicate,and its diversity index,fragmentation degree and heterogeneity were high.展开更多
Under the background of the 'Southwardly Development' of Guangzhou City,this paper chooses Panyu District as the research object and uses the 2005 land use data to quantitatively analyze the landscape layout a...Under the background of the 'Southwardly Development' of Guangzhou City,this paper chooses Panyu District as the research object and uses the 2005 land use data to quantitatively analyze the landscape layout and its change in the study area based on the support of GIS and Fragstats through combining landscape index and gradient analysis.The results show that it is feasible to show urbanization and the change of the spatial pattern of urban landscape through utilizing gradient analysis and landscape index.Over the course of 'Southwardly Development',the urbanization level of Panyu District has been enhanced unceasingly.And the landscape spatial patterns of different land uses and their variation characteristics are obviously different.展开更多
The seismic capacity curves of three types of buildings including frame,frame-shear wall and shear wall ob- tained by pushover analysis under different lateral load patterns are compared with those from nonlinear time...The seismic capacity curves of three types of buildings including frame,frame-shear wall and shear wall ob- tained by pushover analysis under different lateral load patterns are compared with those from nonlinear time history analy- sis.Based on the numerical results obtained a two-phase load pattern:an inverted triangle(first mode)load pattern until the base shear force reaches β times its maximum value,V_(max)followed by a(x/H)~α form,here β and α being some coeffi- cients depending on the type of the structures considered,is proposed in the paper,which can provide excellent approxima- tion of the seismic capacity curve for low-to-mid-rise shear type buildings.Furthermore,it is shown both the two-phase load pattern proposed and the invariant uniform pattern can be used for low-to-mid-rise shear-bending type and low-rise bending type of buildings.No suitable load patterns have been found for high-rise buildings.展开更多
The mechanism of the effects of anisotropic permeability on well patterns and reservoir development are investigated by coordinate transformation, fluid flow analysis, and reservoir development concepts. Anisotropy of...The mechanism of the effects of anisotropic permeability on well patterns and reservoir development are investigated by coordinate transformation, fluid flow analysis, and reservoir development concepts. Anisotropy of permeability has reconstructive effects on well patterns. The originally designed flooding units are broken up, and new pattern units are made up of the wells that belong to different original units. The behavior possesses strong randomness, and leads to a complicated relationship among the injection and production wells, and unpredictable productivity of the formations. To prevent the break-up of well patterns, well lines should be either parallel or perpendicular to the maximum principal direction of the anisotropic permeability （i.e. the fracture direction）. To optimize the development effects ofanisotropic formations, the latitudinal and longitudinal well spacing of the well network are calculated from the principal values of the anisotropic permeability.展开更多
Multivariate pattern analysis（MVPA） is a recently-developed approach for functional magnetic resonance imaging（fMRI） data analyses.Compared with the traditional univariate methods,MVPA is more sensitive to subtle ...Multivariate pattern analysis（MVPA） is a recently-developed approach for functional magnetic resonance imaging（fMRI） data analyses.Compared with the traditional univariate methods,MVPA is more sensitive to subtle changes in multivariate patterns in fMRI data.In this review,we introduce several significant advances in MVPA applications and summarize various combinations of algorithms and parameters in different problem settings.The limitations of MVPA and some critical questions that need to be addressed in future research are also discussed.展开更多
Gas–liquid multiphase flow is a significant phenomenon in chemical processes. The rising behaviors of single bubbles in the quiescent liquids have been investigated but the internal flow patterns and deformation rule...Gas–liquid multiphase flow is a significant phenomenon in chemical processes. The rising behaviors of single bubbles in the quiescent liquids have been investigated but the internal flow patterns and deformation rules of bubbles, which influence the mass transfer efficiency to a large extent, have received much less attention. In this paper, the volume of fluid method was used to calculate the bubble shapes, pressure, velocity distributions,and the flow patterns inside the bubbles. The rising behavior of the bubbles with four different initial diameters,i.e., 3 mm, 5 mm, 7 mm and 9 mm was investigated in four various liquids including water, 61.23% glycerol,86.73% glycerol and 100% glycerol. The results show that the liquid properties and bubble initial diameters have great impacts on bubble shapes. Moreover, flow patterns inside the bubbles with different initial diameters were analyzed and classified into three types under the condition of different bubble shapes. Three correlations for predicting the maximum internal circulation inside the bubbles in 86.73% glycerol were presented and the R-square values were all bigger than 0.98. Through analyzing the pressure and velocity distributions around the bubbles, four rules of bubble deformation were also obtained to explain and predict the shapes.展开更多
BACKGROUND Pancreatic cancer,as the one of most fatal malignancies,remains a critical issue in the global burden of disease.AIM To estimate trends in pancreatic cancer incidence and mortality worldwide in the last thr...BACKGROUND Pancreatic cancer,as the one of most fatal malignancies,remains a critical issue in the global burden of disease.AIM To estimate trends in pancreatic cancer incidence and mortality worldwide in the last three decades.METHODS A descriptive epidemiological study was done.Pancreatic cancer incidence and mortality data were obtained from the database of the World Health Organization.Analysis of pancreatic cancer incidence and mortality during 2020 was performed.The age-standardized rates(ASRs,expressed per 100000)were presented.To estimate trends of incidence and mortality of pancreatic cancer,joinpoint regression analysis was used:the average annual percent change(AAPC)with the corresponding 95%confidence interval(95%CI)was calculated.Additionally,analysis was performed by sex and age.In this paper,the trend analysis included only countries with high and medium data quality.RESULTS A total of 495773(262865 male and 232908 female)new cases and 466003(246840 male and 219163 female)deaths from pancreatic cancer were reported worldwide in 2020.In both sexes,most of the new cases(191348;38.6%of the total)and deaths(182074;39.1%of the total)occurred in the Western Pacific Region.In both sexes,the highest ASRs were found in the European Region,while the lowest rates were reported in the South-East Asia Region.The general pattern of rising pancreatic cancer incidence and mortality was seen across countries worldwide in observed period.Out of all countries with an increase in pancreatic cancer incidence,females in France and India showed the most marked rise in incidence rates(AAPC=+3.9%and AAPC=+3.7%,respectively).Decreasing incidence trends for pancreatic cancer were observed in some countries,but without significance.Out of all countries with an increase in pancreatic cancer mortality rates,Turkmenistan showed the most marked rise both in males(AAPC=+10.0%,95%CI:7.4–12.5)and females(AAPC=+6.4%,95%CI:3.5–9.5).The mortality trends of pancreatic cancer were decreasing in both sexes only in Canada and Mexico.CONCLUSION Further research is needed to explain the cause of large international differences in incidence and mortality trends of pancreatic cancer in last three decades.展开更多
With the wide use of high-resolution remotely sensed imagery, the object-oriented remotely sensed informa- tion classification pattern has been intensively studied. Starting with the definition of object-oriented remo...With the wide use of high-resolution remotely sensed imagery, the object-oriented remotely sensed informa- tion classification pattern has been intensively studied. Starting with the definition of object-oriented remotely sensed information classification pattern and a literature review of related research progress, this paper sums up 4 developing phases of object-oriented classification pattern during the past 20 years. Then, we discuss the three aspects of method- ology in detail, namely remotely sensed imagery segmentation, feature analysis and feature selection, and classification rule generation, through comparing them with remotely sensed information classification method based on per-pixel. At last, this paper presents several points that need to be paid attention to in the future studies on object-oriented RS in- formation classification pattern: 1) developing robust and highly effective image segmentation algorithm for multi-spectral RS imagery; 2) improving the feature-set including edge, spatial-adjacent and temporal characteristics; 3) discussing the classification rule generation classifier based on the decision tree; 4) presenting evaluation methods for classification result by object-oriented classification pattern.展开更多
Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for ope...Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) algorithm.The methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%.展开更多
Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patte...Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patterns of fish species were examined using the C-score under fixed-fixed null model for fish communities in spring and autumn over different years in the Haizhou Bay,China.The results showed that fish assemblages in the whole bay had non-random patterns in spring and autumn over different years.However,the fish co-occurrence patterns were different for the northern and southern fish assemblages in spring and autumn.The northern fish assemblage showed structured pattern,whereas the southern assemblage were randomly assembled in spring.The co-occurrence patterns of fish communities were relatively stable over different years,and the number of significant species pairs in northern assemblage was more than that in the southern assemblage.Environmental heterogeneity played an important role in determining the distributions of fish species that formed significant species pairs,which might affect the co-occurrence patterns of northern and southern assemblages further in the Haizhou Bay.展开更多
Landscape structure is often regarded as an important factor that governs the distribution and abundance of species. Therefore it is critical to understand the landscapes and their dynamics. Patterns of landscape elem...Landscape structure is often regarded as an important factor that governs the distribution and abundance of species. Therefore it is critical to understand the landscapes and their dynamics. Patterns of landscape elements strongly influence the ecological characteristics. This study was designed to document and map the current status of the tropi-cal dry deciduous forest of the Tadoba-Andhari Tiger Reserve （TATR）, Central India, （using IRS P6 LISS IV data） and to describe its landscape structure at three levels of organization viz. landscape, class, and patch. The study area was classified into 10 land cover classes that include 6 vegetation classes. The landscape structure was analyzed using FRAG-STATS using 12 set of indices. The TATR landscapes have a total of 2,307 patches with a mean patch size of 25.67 ha and patch density of 1.7 patches per km2. Amongst all land cover classes, mixed bamboo forest is dominant-it occupied maximum area （77.99%）-while riparian forest is least represented （0.32%）. Mixed forest has maximum number of patches among all vegetation classes. Results have shown that despite being dominant in the area, mixed bamboo forest has low patch density （0.25/100 ha）. Dominance of mixed bamboo forest is attributed to large patch sizes and not to the number of patches. This study has focussed on the approach of integrating satellite forest classification and forest inven-tory data for studying forest landscape patterns.展开更多
Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using...Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using a 1 ha permanent sample plot data for Q.aquifolioides on Sejila Mountain,Tibet Autonomous Region(Tibet),China,we analyzed the population structure of Q.aquifolioides by combining data for diameter class,static life table and survival curve.Simultaneously,the spatial distribution of Q.aquifolioides was studied using Ripley’s L Function in point pattern analysis.The results showed:(1) Individuals in Q.aquifolioides populations were mainly aggregated in the youngest age classes,that accounted for94.3% of the individuals; the older age classes had much smaller populations.Although the youngest age classes(ClassesⅠ and Ⅱ) had fewer individuals than Class Ⅲ,the total number of individuals in classes Ⅰ and Ⅱ was also greater than in classes Ⅳ to Ⅸ.In terms of tree height,fewsaplings,more medium-sized saplings and few large-sized trees were found.The diameter class structure of Q.aquifolioides populations formed an atypical ‘pyramid’type; the population was expanding,but growth was limited,tending toward a stable population.(2) Mortality of Q.aquifolioides increased continuously with age; life expectancy decreased over time,and the survivorship curve was close to a Deevey I curve.(3) The spatial distribution pattern of Q.aquifolioides varied widely across different developmental stages.Saplings and medium-sized tree showed aggregated distributions at the scales of 0–33 m and 0–29 m,respectively.The aggregation intensities of saplings and medium-sized trees at small scales were significantly stronger than that of large-sized trees.However,large-sized trees showed a random distribution at most scales.(4) No correlation was observed among saplings,medium-and large-sized trees at small scales,while a significant and negative association was observed as the scale increased.Strong competition was found among saplings,medium-and large-sized trees,while no significant association was observed between medium-and largesized trees at all scales.Biotic interactions and local ecological characteristics influenced the spatial distribution pattern of Q.aquifolioides populations most strongly.展开更多
Aim Cluster analysis was conducted on data from 5,169 United States （U.S.） Arizona children, age＇s 5-59-months with the goal of delineating patterns of caries in the primary dentition of pre-school children without...Aim Cluster analysis was conducted on data from 5,169 United States （U.S.） Arizona children, age＇s 5-59-months with the goal of delineating patterns of caries in the primary dentition of pre-school children without a priori pattern definitions. Methodology Cluster analyses were conducted using all data for children ages 0-4 years in aggregate： 1） for all subjects, and 2） for subjects without crowned restored teeth. Each of these two sets of analyses consisted of 8 differently specified cluster analyses as a validation procedure. Results The caries patterns identified from the clustering analysis are： 1） smooth surfaces （other than the maxillary incisor）, 2） maxillary incisor, 3） occlusal surfaces of first molars, and 4） pit and fissure surfaces of second molars. Conclusion The cluster analysis findings were consistent with results produced by multidimensional scaling. These cross-validated patterns may represent resulting disease conditions from different risks or the timing of various risk factor exposures. As such, the patterns may be useful case definitions for caries risk factor investigations in children under 60 months of age.展开更多
Auxin plays important roles in various aspects of plant growth and development （Zhao, 2010）. In Arabidopsis, a number of YUCCA （YUC） genes, which are involved in auxin biosyn- thesis, have been identified （Zhao e...Auxin plays important roles in various aspects of plant growth and development （Zhao, 2010）. In Arabidopsis, a number of YUCCA （YUC） genes, which are involved in auxin biosyn- thesis, have been identified （Zhao et al., 2001; Woodward et al., 2005; Cheng et al., 2006, 2007; Kim et al., 2007; Chen et al., 2014）. YUC genes encode flavin monooxygenases （FMOs） that convert indole-3-pyruvate （IPA） to indole-3-acetic acid （IAA） （Zhao, 2012）. The Arabidopsis YUC family is comprised of 11 members （Zhao et al., 2001;展开更多
Plant photosynthetic rate is affected by stomatal status and internal CO2 carboxylation. Understanding which process determines photosynthetic rate is essential for developing strategies for breeding crops with high p...Plant photosynthetic rate is affected by stomatal status and internal CO2 carboxylation. Understanding which process determines photosynthetic rate is essential for developing strategies for breeding crops with high photosynthetic efficiency. In this study, we identified different physiological patterns of photosynthetic rate in two different rice populations. Photosynthetic gas exchange parameters were measured during the flowering stage in two rice populations. Clustering and correlation analyses were performed on the resulting data. Five or six groups were defined by K-means clustering according to differences in net photosynthetic rates(Pn). According to differences in stomatal conductance(gs) and carboxylation efficiency(CE), each group was clustered into three subgroups characterized by physiological patterns stomatal pattern, carboxylation pattern, and intermediate pattern. Pn was significantly correlated with gs(r = 0.810) and CE(r = 0.531). Pn was also significantly correlated with gs and CE in the three physiological patterns. The correlation coefficients were highest in the stomatal pattern(0.905 and 0.957) and lowest in the carboxylation pattern(0.825 and 0.859). Higher correlation coefficients between Pn and gs or CE in the three physiological patterns indicate that clustering is very important for understanding factors limiting rice photosynthesis. ? 2013 Production and hosting by Elsevier B.V. on behalf of Crop Science Society of展开更多
基金funded by the Technical Development(Entrusted)Project of Science and Department of SINOPEC(Grant No.P23240-4)the National Natural Science Foundation of China(Grant Nos.42172165,42272143 and 2025ZD1403901-05)。
文摘The Wufeng–Longmaxi Formation derives its name from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation,found in sequence in the Sichuan Basin.This formation hosts rich shale gas reservoirs,and its shale gas enrichment patterns are examined in this study using data from 1197 shale samples collected from 14 wells.Five basic and three key parameters,eight in all,are assessed for each sample.The five basic parameters include burial depth and the contents of four mineral types—quartz,clay,carbonate,and other minerals;the three key parameters,representing shale gas enrichment,are total organic carbon(TOC)content,porosity,and gas content.The SHapley Additive exPlanations(SHAP)analysis originated in game theory is used here in an interpretable machine learning framework,to address issues of heterogeneous data structure,noisy relationships,and multi-objective optimization.An evaluation of the ranking,contribution values,and conditions of changes for these parameters offers new quantitative insights into shale gas enrichment patterns.A quantitative analysis of the relationship between data-sets identifies the primary factors controlling TOC,porosity,and gas content of shale gas reservoirs.The results show that TOC and porosity jointly influence gas content;mineral content has a significant impact on both,TOC and porosity;and the burial depth governs porosity which,in turn,affects the conditions under which shale gas is preserved.Input parameter thresholds are also determined and provide a basis for the establishment of quantitative criteria to evaluate shale gas enrichment.The predictive accuracy of the model used in this study is significantly improved by the step-wise addition of two input parameters,namely TOC and porosity,separately and together.Thus,the game theory method in big data-driven analysis uses a combination of TOC and porosity to evaluate the gas content with encouraging results—suggesting that these are the key parameters that indicate source rock and reservoir properties.
基金Supported by College Student Innovation and Entrepreneurship Training Program(S202210553003)Hunan Provincial Education Department Outstanding Youth Research Project(23B0820).
文摘Kinesins are a superfamily of proteins widely present in eukaryotes,playing crucial roles in plant cell wall assembly,cell elongation regulation,gravity sensing,and fertility control.In this study,bioinformatics analysis of the OsKMP2 gene(LOC_Os02g28850)was performed using online tools such as ExPASy-ProtParam,ProtScale,CD-search,and DNAMAN software.Additionally,qRT-PCR was employed to analyze the tissue expression pattern of OsKMP2.The results showed that the molecular weight of the OsKMP2 is 118.39728 kDa,and it is a hydrophilic and unstable acidic protein.Secondary structure prediction revealed that it primarily consists ofα-helices(69.45%),random coils(25.19%),and extended strands(5.36%).The gene was expressed in various rice tissues,with the highest expression level observed in leaves.These results indicate that the OsKMP2 gene exhibits high evolutionary conservation and functional diversity in rice.
基金supported by the National Key R&D Program of China(2022YFD1200400)the National Natural Science Foundation of China(32301851)。
文摘The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examining their phylogenetic relationships,conserved motifs,gene structures,and syntenic relationships.The analysis identified 54 Ah PR10 genes,which were classified into eight groups based on phylogenetic relationships,supported by gene structure and conserved motif characterization.Analysis of chromosomal distribution and synteny demonstrated that segmental duplications played a crucial role in the expansion of the Ah PR10 gene family.The identified Ah PR10 genes exhibited both constitutive and inducible expression patterns.Significantly,Ah PR10-7,Ah PR10-33,and Ah PR10-41 demonstrated potential importance in peanut resistance to Aspergillus flavus.In vitro fungistatic experiments demonstrated that recombinant Ah PR10-33 effectively inhibited A.flavus mycelial growth.These findings provide valuable insights for future investigations into Ah PR10 functions in protecting peanut from A.flavus infection.
基金National Natural Science Foundation of China,No.42471202,No.72441005。
文摘Existing studies on the Regional Comprehensive Economic Partnership(RCEP)mainly focused on institutional features,macro-economic impacts,and trade-network structures,while its geographic attributes and their implications remain underexplored.Taking the RCEP as a case,this paper examines how the FTA reshapes China’s trade geography and validates these effects with an enhanced GTAP model,providing an empirical basis for advancing trade-geography theory.Key findings include:(1)RCEP significantly reduces regional trade costs.After full implementation of the agreement,the average tariffs among member countries will decrease to 40.5%of the pre-implementation level,while import and export trade facilitation levels improve by 34.3%and 29.6%,respectively.However,these improvements exhibit marked regional disparities.(2)RCEP asymmetrically promotes China’s foreign trade growth,with stronger import stimulation than export expansion,alongside significant product-specific variations.(3)The agreement reshapes China’s trade geography,driving a 7.66%increase in intra-RCEP trade while reducing extra-RCEP trade by 0.80%.(4)The restructuring of China’s trade patterns under RCEP emerges from the complex interplay of trade creation,diversion,and crowding-out effects.Accordingly,China should further harmonize regional tariff schedules,enhance trade-facilitation mechanisms,strengthen industrial competitiveness and expand multilateral partnerships.
基金The Fundamental Research Funds for the Central Universities,the Scientific Innovation Research of College Graduates in Jiangsu Province(No.KYLX_0177)
文摘In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purposes by applying three methods： the support vector machine （SVM） model, the radial basis function neural network （RBFNN） model and the multinomial logit （MNL） model. The effect of explanatory factors on trip chaining behaviors and their contribution to model performace were investigated by sensitivity analysis. Results show that the SVM model has a better performance than the RBFNN model and the MNL model due to its higher overall and partial accuracy, indicating its recognition advantage under a smai sample size scenario. It is also proved that the SVM model is capable of estimating the effect of multi-category factors on trip chaining behaviors more accurately. The different contribution of explanatory, factors to trip chaining pattern recognition reflects the importance of refining trip chaining patterns ad exploring factors that are specific to each pattern. It is shown that the SVM technology in travel demand forecast modeling and analysis of explanatory variable effects is practical.
基金Supported by Foundation Projects of Philosophical Social Sciences Research and Planning in Xinjiang Uygur Autonomous Region(07JYB027)~~
文摘Based on the land use status map of Shihezi City,the land use landscape map of Shihezi City was made with the support of GIS then many landscape indices were selected to quantitatively analyze the landscape pattern characteristics of Shihezi Oasis from three aspects of landscape diversity index,landscape space configuration index and plaque characteristics index. The results showed that the main plaque types of the landscape in Shihezi reclamation area are arable land and water areas,which totally account for 58% of the total area; farmland,gardens,woodland,urban sites,industrial and mining land use were embedded in this oasis landscape in the form of mosaics,and their fractal index was high due to the strong impact of human activities; arable land and mining land distribution was scattered,but marshes and other uncultivated land were relatively concentrated. The dominance degree of the landscape was low because there was no advantageous type in this landscape and all patches distributed equably which was easily to be disturbed so that the whole landscape was unstable. Comprehensively speaking,the landscape in Shihezi region was rather complicate,and its diversity index,fragmentation degree and heterogeneity were high.
文摘Under the background of the 'Southwardly Development' of Guangzhou City,this paper chooses Panyu District as the research object and uses the 2005 land use data to quantitatively analyze the landscape layout and its change in the study area based on the support of GIS and Fragstats through combining landscape index and gradient analysis.The results show that it is feasible to show urbanization and the change of the spatial pattern of urban landscape through utilizing gradient analysis and landscape index.Over the course of 'Southwardly Development',the urbanization level of Panyu District has been enhanced unceasingly.And the landscape spatial patterns of different land uses and their variation characteristics are obviously different.
文摘The seismic capacity curves of three types of buildings including frame,frame-shear wall and shear wall ob- tained by pushover analysis under different lateral load patterns are compared with those from nonlinear time history analy- sis.Based on the numerical results obtained a two-phase load pattern:an inverted triangle(first mode)load pattern until the base shear force reaches β times its maximum value,V_(max)followed by a(x/H)~α form,here β and α being some coeffi- cients depending on the type of the structures considered,is proposed in the paper,which can provide excellent approxima- tion of the seismic capacity curve for low-to-mid-rise shear type buildings.Furthermore,it is shown both the two-phase load pattern proposed and the invariant uniform pattern can be used for low-to-mid-rise shear-bending type and low-rise bending type of buildings.No suitable load patterns have been found for high-rise buildings.
文摘The mechanism of the effects of anisotropic permeability on well patterns and reservoir development are investigated by coordinate transformation, fluid flow analysis, and reservoir development concepts. Anisotropy of permeability has reconstructive effects on well patterns. The originally designed flooding units are broken up, and new pattern units are made up of the wells that belong to different original units. The behavior possesses strong randomness, and leads to a complicated relationship among the injection and production wells, and unpredictable productivity of the formations. To prevent the break-up of well patterns, well lines should be either parallel or perpendicular to the maximum principal direction of the anisotropic permeability （i.e. the fracture direction）. To optimize the development effects ofanisotropic formations, the latitudinal and longitudinal well spacing of the well network are calculated from the principal values of the anisotropic permeability.
基金supported by grants from the National Natural Science Foundation of China (30900366,31070905)
文摘Multivariate pattern analysis（MVPA） is a recently-developed approach for functional magnetic resonance imaging（fMRI） data analyses.Compared with the traditional univariate methods,MVPA is more sensitive to subtle changes in multivariate patterns in fMRI data.In this review,we introduce several significant advances in MVPA applications and summarize various combinations of algorithms and parameters in different problem settings.The limitations of MVPA and some critical questions that need to be addressed in future research are also discussed.
基金Supported by the National Natural Science Foundation of China(21276132)the Transformation Project of Scientific and Technological Achievements of Qingdao(16-6-2-50-nsh)
文摘Gas–liquid multiphase flow is a significant phenomenon in chemical processes. The rising behaviors of single bubbles in the quiescent liquids have been investigated but the internal flow patterns and deformation rules of bubbles, which influence the mass transfer efficiency to a large extent, have received much less attention. In this paper, the volume of fluid method was used to calculate the bubble shapes, pressure, velocity distributions,and the flow patterns inside the bubbles. The rising behavior of the bubbles with four different initial diameters,i.e., 3 mm, 5 mm, 7 mm and 9 mm was investigated in four various liquids including water, 61.23% glycerol,86.73% glycerol and 100% glycerol. The results show that the liquid properties and bubble initial diameters have great impacts on bubble shapes. Moreover, flow patterns inside the bubbles with different initial diameters were analyzed and classified into three types under the condition of different bubble shapes. Three correlations for predicting the maximum internal circulation inside the bubbles in 86.73% glycerol were presented and the R-square values were all bigger than 0.98. Through analyzing the pressure and velocity distributions around the bubbles, four rules of bubble deformation were also obtained to explain and predict the shapes.
基金Supported by Ministry of Education,Science and Technological development,Republic of Serbia,2011-2020,No.175042.
文摘BACKGROUND Pancreatic cancer,as the one of most fatal malignancies,remains a critical issue in the global burden of disease.AIM To estimate trends in pancreatic cancer incidence and mortality worldwide in the last three decades.METHODS A descriptive epidemiological study was done.Pancreatic cancer incidence and mortality data were obtained from the database of the World Health Organization.Analysis of pancreatic cancer incidence and mortality during 2020 was performed.The age-standardized rates(ASRs,expressed per 100000)were presented.To estimate trends of incidence and mortality of pancreatic cancer,joinpoint regression analysis was used:the average annual percent change(AAPC)with the corresponding 95%confidence interval(95%CI)was calculated.Additionally,analysis was performed by sex and age.In this paper,the trend analysis included only countries with high and medium data quality.RESULTS A total of 495773(262865 male and 232908 female)new cases and 466003(246840 male and 219163 female)deaths from pancreatic cancer were reported worldwide in 2020.In both sexes,most of the new cases(191348;38.6%of the total)and deaths(182074;39.1%of the total)occurred in the Western Pacific Region.In both sexes,the highest ASRs were found in the European Region,while the lowest rates were reported in the South-East Asia Region.The general pattern of rising pancreatic cancer incidence and mortality was seen across countries worldwide in observed period.Out of all countries with an increase in pancreatic cancer incidence,females in France and India showed the most marked rise in incidence rates(AAPC=+3.9%and AAPC=+3.7%,respectively).Decreasing incidence trends for pancreatic cancer were observed in some countries,but without significance.Out of all countries with an increase in pancreatic cancer mortality rates,Turkmenistan showed the most marked rise both in males(AAPC=+10.0%,95%CI:7.4–12.5)and females(AAPC=+6.4%,95%CI:3.5–9.5).The mortality trends of pancreatic cancer were decreasing in both sexes only in Canada and Mexico.CONCLUSION Further research is needed to explain the cause of large international differences in incidence and mortality trends of pancreatic cancer in last three decades.
基金Under the auspices of the National Natural Science Foundation of China (No. 40301038), Talents Recruitment Foun-dation of Nanjing University
文摘With the wide use of high-resolution remotely sensed imagery, the object-oriented remotely sensed informa- tion classification pattern has been intensively studied. Starting with the definition of object-oriented remotely sensed information classification pattern and a literature review of related research progress, this paper sums up 4 developing phases of object-oriented classification pattern during the past 20 years. Then, we discuss the three aspects of method- ology in detail, namely remotely sensed imagery segmentation, feature analysis and feature selection, and classification rule generation, through comparing them with remotely sensed information classification method based on per-pixel. At last, this paper presents several points that need to be paid attention to in the future studies on object-oriented RS in- formation classification pattern: 1) developing robust and highly effective image segmentation algorithm for multi-spectral RS imagery; 2) improving the feature-set including edge, spatial-adjacent and temporal characteristics; 3) discussing the classification rule generation classifier based on the decision tree; 4) presenting evaluation methods for classification result by object-oriented classification pattern.
基金supported by the Centro de Investigación para el Desarrollo y la Innovación (CIDI) from Universidad Pontificia Bolivariana (No. 636B-06/16–57)。
文摘Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) algorithm.The methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%.
基金funded by the National Natural Science Foundation of China (No. 31772852)the Fundamental Research Funds for the Central Universities (Nos. 2015 62030, 201612004)the Public Science and Technology Research Funds Projects of Ocean (No. 201305030)
文摘Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patterns of fish species were examined using the C-score under fixed-fixed null model for fish communities in spring and autumn over different years in the Haizhou Bay,China.The results showed that fish assemblages in the whole bay had non-random patterns in spring and autumn over different years.However,the fish co-occurrence patterns were different for the northern and southern fish assemblages in spring and autumn.The northern fish assemblage showed structured pattern,whereas the southern assemblage were randomly assembled in spring.The co-occurrence patterns of fish communities were relatively stable over different years,and the number of significant species pairs in northern assemblage was more than that in the southern assemblage.Environmental heterogeneity played an important role in determining the distributions of fish species that formed significant species pairs,which might affect the co-occurrence patterns of northern and southern assemblages further in the Haizhou Bay.
基金National Natural Resource Management System(NNRMS)and Ministry of Environment and Forests(MoEF),Government of India for funding the project"Mapping of National Parks and Wildlife Sanctuaries"
文摘Landscape structure is often regarded as an important factor that governs the distribution and abundance of species. Therefore it is critical to understand the landscapes and their dynamics. Patterns of landscape elements strongly influence the ecological characteristics. This study was designed to document and map the current status of the tropi-cal dry deciduous forest of the Tadoba-Andhari Tiger Reserve （TATR）, Central India, （using IRS P6 LISS IV data） and to describe its landscape structure at three levels of organization viz. landscape, class, and patch. The study area was classified into 10 land cover classes that include 6 vegetation classes. The landscape structure was analyzed using FRAG-STATS using 12 set of indices. The TATR landscapes have a total of 2,307 patches with a mean patch size of 25.67 ha and patch density of 1.7 patches per km2. Amongst all land cover classes, mixed bamboo forest is dominant-it occupied maximum area （77.99%）-while riparian forest is least represented （0.32%）. Mixed forest has maximum number of patches among all vegetation classes. Results have shown that despite being dominant in the area, mixed bamboo forest has low patch density （0.25/100 ha）. Dominance of mixed bamboo forest is attributed to large patch sizes and not to the number of patches. This study has focussed on the approach of integrating satellite forest classification and forest inven-tory data for studying forest landscape patterns.
基金financially supported by the National Key Technology Support Program(Grant No.2013BAC04B01)the National Natural Science Foundation of China(Grant No.31460200)
文摘Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using a 1 ha permanent sample plot data for Q.aquifolioides on Sejila Mountain,Tibet Autonomous Region(Tibet),China,we analyzed the population structure of Q.aquifolioides by combining data for diameter class,static life table and survival curve.Simultaneously,the spatial distribution of Q.aquifolioides was studied using Ripley’s L Function in point pattern analysis.The results showed:(1) Individuals in Q.aquifolioides populations were mainly aggregated in the youngest age classes,that accounted for94.3% of the individuals; the older age classes had much smaller populations.Although the youngest age classes(ClassesⅠ and Ⅱ) had fewer individuals than Class Ⅲ,the total number of individuals in classes Ⅰ and Ⅱ was also greater than in classes Ⅳ to Ⅸ.In terms of tree height,fewsaplings,more medium-sized saplings and few large-sized trees were found.The diameter class structure of Q.aquifolioides populations formed an atypical ‘pyramid’type; the population was expanding,but growth was limited,tending toward a stable population.(2) Mortality of Q.aquifolioides increased continuously with age; life expectancy decreased over time,and the survivorship curve was close to a Deevey I curve.(3) The spatial distribution pattern of Q.aquifolioides varied widely across different developmental stages.Saplings and medium-sized tree showed aggregated distributions at the scales of 0–33 m and 0–29 m,respectively.The aggregation intensities of saplings and medium-sized trees at small scales were significantly stronger than that of large-sized trees.However,large-sized trees showed a random distribution at most scales.(4) No correlation was observed among saplings,medium-and large-sized trees at small scales,while a significant and negative association was observed as the scale increased.Strong competition was found among saplings,medium-and large-sized trees,while no significant association was observed between medium-and largesized trees at all scales.Biotic interactions and local ecological characteristics influenced the spatial distribution pattern of Q.aquifolioides populations most strongly.
基金Support for this work was through NIH NIDCR NRSA #T32-DE07255
文摘Aim Cluster analysis was conducted on data from 5,169 United States （U.S.） Arizona children, age＇s 5-59-months with the goal of delineating patterns of caries in the primary dentition of pre-school children without a priori pattern definitions. Methodology Cluster analyses were conducted using all data for children ages 0-4 years in aggregate： 1） for all subjects, and 2） for subjects without crowned restored teeth. Each of these two sets of analyses consisted of 8 differently specified cluster analyses as a validation procedure. Results The caries patterns identified from the clustering analysis are： 1） smooth surfaces （other than the maxillary incisor）, 2） maxillary incisor, 3） occlusal surfaces of first molars, and 4） pit and fissure surfaces of second molars. Conclusion The cluster analysis findings were consistent with results produced by multidimensional scaling. These cross-validated patterns may represent resulting disease conditions from different risks or the timing of various risk factor exposures. As such, the patterns may be useful case definitions for caries risk factor investigations in children under 60 months of age.
基金financially supported by the grant from the National Plant Transgenic Program(No.2013ZX08003-003)from Ministry of Agriculture of the People’s Republic of China
文摘Auxin plays important roles in various aspects of plant growth and development （Zhao, 2010）. In Arabidopsis, a number of YUCCA （YUC） genes, which are involved in auxin biosyn- thesis, have been identified （Zhao et al., 2001; Woodward et al., 2005; Cheng et al., 2006, 2007; Kim et al., 2007; Chen et al., 2014）. YUC genes encode flavin monooxygenases （FMOs） that convert indole-3-pyruvate （IPA） to indole-3-acetic acid （IAA） （Zhao, 2012）. The Arabidopsis YUC family is comprised of 11 members （Zhao et al., 2001;
基金funded by the National Basic Research Program of China (2009CB118605)the National Natural Science Fund of China (30370853)
文摘Plant photosynthetic rate is affected by stomatal status and internal CO2 carboxylation. Understanding which process determines photosynthetic rate is essential for developing strategies for breeding crops with high photosynthetic efficiency. In this study, we identified different physiological patterns of photosynthetic rate in two different rice populations. Photosynthetic gas exchange parameters were measured during the flowering stage in two rice populations. Clustering and correlation analyses were performed on the resulting data. Five or six groups were defined by K-means clustering according to differences in net photosynthetic rates(Pn). According to differences in stomatal conductance(gs) and carboxylation efficiency(CE), each group was clustered into three subgroups characterized by physiological patterns stomatal pattern, carboxylation pattern, and intermediate pattern. Pn was significantly correlated with gs(r = 0.810) and CE(r = 0.531). Pn was also significantly correlated with gs and CE in the three physiological patterns. The correlation coefficients were highest in the stomatal pattern(0.905 and 0.957) and lowest in the carboxylation pattern(0.825 and 0.859). Higher correlation coefficients between Pn and gs or CE in the three physiological patterns indicate that clustering is very important for understanding factors limiting rice photosynthesis. ? 2013 Production and hosting by Elsevier B.V. on behalf of Crop Science Society of
