Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANIC...Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANICLE 1(OP1),a gain-of-function allele of LIGULELESS 1(LG1),controlling the spread-panicle phenotype.This allele results from a 48-bp deletion in the LG1 upstream region and promotes pulvinus development at the base of the primary branch.Increased OP1 expression and altered panicle phenotype in chimeric transgenic plants and upstream-region knockout mutants indicated that the deletion regulates spread-panicle architecture in the mutant spread panicle 1(sp1).Knocking out BRASSINOSTEROID UPREGULATED1(BU1)gene in the background of OP1 complementary plants resulted in compact panicles,suggesting OP1 may regulate inflorescence architecture via the brassinosteroid signaling pathway.We regard that manipulating the upstream regulatory region of OP1 or genes involved in BR signal pathway could be an efficient way to improve rice inflorescence architecture.展开更多
Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual impairment.Increasing evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress o...Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual impairment.Increasing evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress of AMD,and the function of anti-oxidant capacity of PRE plays a fundamental physiological role.Nuclear factor erythroid 2 related factor 2(Nrf2)is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative genes.Its functions of protecting RPE cells against oxidative stress(OS)and ensuing physiological changes,including inflammation,mitochondrial damage and autophagy dysregulation,have already been elucidated.Understanding the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD pathogenesis.For the first time,this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis,including proteins and miRNAs,and their underlying molecular mechanisms,which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.展开更多
By building a composite index for measuring national digital economy development and sectoral digital intensities,this paper derives metrics of industry-level digital economy penetration under the framework of special...By building a composite index for measuring national digital economy development and sectoral digital intensities,this paper derives metrics of industry-level digital economy penetration under the framework of specialization within global value chains(GVCs),systematically analyzes the mechanisms through which digital economy development affects GVCs upstreamness,and examines the moderating effect of institutional quality.The study shows that different dimensions of digital economy development significantly boost GVCs upstreamness,a conclusion that holds even after accounting for endogeneity through dynamic panel models with instrumental variables based on past data.Further research shows that technological innovation capabilities and resource allocation efficiency have gradually become important channels for digital economy development to boost GVCs upstreamness.Adding indicators on institutional quality reveals that greater institutional quality not only directly promotes GVCs upstreamness but also reinforces the impact of digital economy development on higher GVCs positioning.展开更多
Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Wes...Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Western Iraq as an example,a new reservoir classification and discrimination method is established by using the K-means clustering method and the Bayesian discrimination method.These methods are applied to non-cored wells to calculate the discrimination accuracy of the reservoir type,and thus the main reasons for low accuracy of reservoir discrimination are clarified.The results show that the discrimination accuracy of reservoir type based on K-means clustering and Bayesian stepwise discrimination is strongly related to the accuracy of the core data.The discrimination accuracy rate of TypeⅠ,TypeⅡ,and TypeⅤreservoirs is found to be significantly higher than that of TypeⅢand TypeⅣreservoirs using the method of combining K-means clustering and Bayesian theory based on logging data.Although the recognition accuracy of the new methodology for the TypeⅣreservoir is low,with average accuracy the new method has reached more than 82%in the entire study area,which lays a good foundation for rapid and accurate discrimination of reservoir types and the fine evaluation of a reservoir.展开更多
An integrated geological-petrophysical analysis of the rudist-bearing sequence of the Cretaceous Sarvak Formation is given one giant oilfield,and provides an improved understanding of this main reservoir in the Abadan...An integrated geological-petrophysical analysis of the rudist-bearing sequence of the Cretaceous Sarvak Formation is given one giant oilfield,and provides an improved understanding of this main reservoir in the Abadan Plain,in the Zagros Basin,SW Iran.The main objective of this study is to evaluate reservoir potential of the Sarvak Formation,and then to utilize the calibrated well log signature to correlate reservoir potential in un-cored wells.Eight main facies are recognized and categorized in five facies groups:lagoon,shoal,rudist-biostrome,slope,and shallow open marine,deposited on a shelf carbonate platform.Given the distribution of diagenetic products and their effects on pore systems,three diagenetic facies namely,(DF-1)low dissolution and cementation;(DF-2);high dissolution;and(DF-3)high cementation are differentiated.The initial sedimentary characteristics in combination with distribution of diagenetic products play an important role in reservoir quality heterogeneity.The effect of diagenetic processes related to disconformities mainly depends on the facies nature below these surfaces.Grain-dominated facies of shoal and rudist debris,observed below the Cenomanian–Turonian disconformity,are mostly characterized by high dissolution and interconnected pore systems.Finally,depositional and diagenetic facies in the studied wells are correlated by petrophysical well log data,leading to distribution of the reservoir zones.Data obtained can be utilized for efficient reservoir characterization of the Sarvak Formation and its equivalent units in the Arabian Plate.展开更多
The bedrock weathered crust in front of the Altun Mountains in the Qaidam Basin,western China,is different from others because this is a salt-lake basin,where saline water fluid infiltrates and is deposited in the ove...The bedrock weathered crust in front of the Altun Mountains in the Qaidam Basin,western China,is different from others because this is a salt-lake basin,where saline water fluid infiltrates and is deposited in the overlying strata.A large amount of gypsum infills the bedrock weathered crust,and this has changed the pore structure.Using core observation,polarized light microscopy,electron probe,physical property analysis and field emission scanning electron microscopy experiments,the characteristics of the weathered bedrock have been studied.There are cracks and a small number of dissolved pores in the interior of the weathered crust.Matrix micropores are widely developed,especially the various matrix cracks formed by tectonics and weathering,as well as the stress characteristics of small dissolved pores,and physical properties such as porosity and permeability.This‘dual structure’developed in the bedrock is important for guiding the exploration of the lake basin bedrock for natural gas.展开更多
Unsteady wash waves generated by a ship with constant speed moving across an uneven bottom topography are investigated by numerical simulations based on a Mixed Euler–Lagrange(MEL) method. The transition is accomplis...Unsteady wash waves generated by a ship with constant speed moving across an uneven bottom topography are investigated by numerical simulations based on a Mixed Euler–Lagrange(MEL) method. The transition is accomplished by the ship traveling from the depth h1 into the depth h2 via a step bottom. A small tsunami would be created after this transition. However, the unsteady wave-making resistance induced by this new phenomenon has not been well documented by literature. Therefore, the main purpose of the present study is to quantify the effects of an uneven bottom on the unsteady wash waves and wave-making resistance acting on the ship. An upwind differential scheme is commonly used in the Euler method to deal with the convection terms under free-surface condition to prevent waves in the upstream. Evidently, it cannot be applied to the present problem due to upstream waves generated by the ship would be dampened by the upwind scheme. The central differential scheme provides more accurate results,but it is not unconditionally stable. An MEL method is therefore employed to investigate the upstream wave generated by the ship moving over the uneven bottom. Simulation results show that the hydrodynamic interaction between the ship and the uneven bottom could initiate an upstream tsunami, as well as unsteady wave-making resistance on ships.The unsteady wave-making resistance oscillates periodically, and the amplitude and period of the oscillations are highly dependent on speed and water depth.展开更多
We use the Wind Farm Parameterization(WFP) scheme coupled with the Weather Research and Forecasting model under multiple resolution regimes to simulate turbulent wake dynamics generated by a real onshore wind farm and...We use the Wind Farm Parameterization(WFP) scheme coupled with the Weather Research and Forecasting model under multiple resolution regimes to simulate turbulent wake dynamics generated by a real onshore wind farm and their influence at the local meteorological scale. The model outputs are compared with earlier modeling and observation studies. It is found that higher vertical and horizontal resolutions have great impacts on the simulated wake flow dynamics. The corresponding wind speed deficit and turbulent kinetic energy results match well with previous studies. In addition, the effect of horizontal resolution on near-surface meteorology is significantly higher than that of vertical resolution. The wake flow field extends from the start of the wind farm to downstream within 10 km, where the wind speed deficit may exceed 4%. For a height of 150 m or at a distance of about 25 km downstream, the wind speed deficit is around 2%. This indicates that, at a distance of more than 25 km downstream, the impact of the wind turbines can be ignored. Analysis of near-surface meteorology indicates a night and early morning warming near the surface, and increase in near-surface water vapor mixing ratio with decreasing surface sensible and latent heat fluxes. During daytime, a slight cooling near the surface and decrease in the near-surface water vapor mixing ratio with increasing surface sensible and latent heat fluxes is noticed over the wind farm area.展开更多
This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,00...This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,000 scale digital map, six factors including slope angle, rainstorm days, buffer of river channels, maximum runoff discharge of standard area, debris flow distribution density and flood disaster history were analyzed and superimposed to create the torrent risk evaluation map. Population density, farmland percentage, house property, and GDP as indexes accounting for torrent hazards were analyzed in terms of vulnerability mapping. Torrent risk zonation by means of GIS was overlaid on the two data layers of hazard and vulnerability. Then each grid unit with a resolution of 500 m- 500 m was divided into four categories of the risk: extremely high, high, moderate and low. Finally the same level risk was combined into a confirmed zone, which represents torrent risk of the study area. The risk evaluation result in the upper Red River Basin shows that the extremely high risk area of 13,150 km^2 takes up 17.9% of the total inundated area, the high risk area of 33,783 km^2 is 45.9%, the moderate risk area of 18,563 km^2 is 25.2% and the low risk area of 8115 km^2 is 11.0%.展开更多
We present in this paper some new evidence for the change during the Quaternary in kinematics of faults cutting the eastern margin of the Tibetan Plateau. It shows that significant shortening deformation occurred duri...We present in this paper some new evidence for the change during the Quaternary in kinematics of faults cutting the eastern margin of the Tibetan Plateau. It shows that significant shortening deformation occurred during the Early Pleistocene, evidenced by eastward thrusting of Mesozoic carbonates on the Pliocene lacustrine deposits along the Minjiang upstream fault zone and by development of the transpressional ridges of basement rocks along the Anninghe river valley. The Middle Pleistocene seems to be a relaxant stage with local development of the intra-mountain basins particularly prominent along the Minjiang Upstream and along the southern segment of the Anninghe River Valley. This relaxation may have been duo to a local collapse of the thickened crust attained during the late Neogene to early Pleistocene across this marginal zone. Fault kinematics has been changed since the late Pleistocene, and was predominated by reverse sinistral strike-slip along the Minshan Uplift, reverse dextral strike-slip on the Longmenshan fault zone and pure sinistral strike-slip on the Anninghe fault. This change in fault kinematics during the Quaternary allows a better understanding of the mechanism by which the marginal ranges of the plateau has been built through episodic activities.展开更多
The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regen...The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regeneration.Our previous study observed the dynamic changes of genes in L4–6 dorsal root ganglion after rat sciatic nerve crush using transcriptome sequencing.Our current study focused on upstream growth factors and found that a total of 19 upstream growth factors were dysregulated in dorsal root ganglions at 3,9 hours,1,4,or 7 days after nerve crush,compared with the 0 hour control.Thirty-six rat models of sciatic nerve crush injury were prepared as described previously.Then,they were divided into six groups to measure the expression changes of representative genes at 0,3,9 hours,1,4 or 7 days post crush.Our current study measured the expression levels of representative upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin genes,and explored critical signaling pathways and biological process through bioinformatic analysis.Our data revealed that many of these dysregulated upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin,participated in tissue remodeling and axon growth-related biological processes Therefore,the experiment described the expression pattern of upstream growth factors in the dorsal root ganglia after peripheral nerve injury.Bioinformatic analysis revealed growth factors that may promote repair and regeneration of damaged peripheral nerves.All animal surgery procedures were performed in accordance with Institutional Animal Care Guidelines of Nantong University and ethically approved by the Administration Committee of Experimental Animals,China(approval No.20170302-017)on March 2,2017.展开更多
Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator o...Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator of leaf and flower senescence,but the molecular mechanism of ethylene-induced ovule senescence has not yet been elucidated.In this study,we found that blockage of fertilization caused ovule abortion in the pear cultivar‘1913’.According to transcriptome and phytohormone content data,ethylene biosynthesis was activated by pollination.At the same time,ethylene overaccumulated in ovules,where cells were sensitive to ethylene signals in the absence of fertilization.We identified a transcription factor in the ethylene signal response,ethylene-insensitive 3-like(EIL1),as a likely participant in ovule senescence.Overexpression of PbEIL1 in tomato caused precocious onset of ovule senescence.We further found that EIL1 could directly bind to the promoter of the SENESCENCE-ASSOCIATED CYSTEINE PROTEINASE 1(PbCysp1)gene and act upstream of senescence.Yeast one-hybrid and dual-luciferase assays revealed the interaction of the transcription factor and the promoter DNA sequence and demonstrated that PbEIL1 enhanced the action of PbCysp1.Collectively,our results provide new insights into how ethylene promotes the progression of unfertilized ovule senescence.展开更多
In fleshy fruits,organic acids are the main source of fruit acidity and play an important role in regulating osmotic pressure,pH homeostasis,stress resistance,and fruit quality.The transport of organic acids from the ...In fleshy fruits,organic acids are the main source of fruit acidity and play an important role in regulating osmotic pressure,pH homeostasis,stress resistance,and fruit quality.The transport of organic acids from the cytosol to the vacuole and their storage are complex processes.A large number of transporters carry organic acids from the cytosol to the vacuole with the assistance of various proton pumps and enzymes.However,much remains to be explored regarding the vacuolar transport mechanism of organic acids as well as the substances involved and their association.In this review,recent advances in the vacuolar transport mechanism of organic acids in plants are summarized from the perspectives of transporters,channels,proton pumps,and upstream regulators to better understand the complex regulatory networks involved in fruit acid formation.展开更多
The Explicit Upstream FEM (EU-FEM) proposed in this paper not only possesses the advantages of saving memory and CPU time for FDM, but also fits boundary easily, arranges nodal points flexibly and makes local grids fi...The Explicit Upstream FEM (EU-FEM) proposed in this paper not only possesses the advantages of saving memory and CPU time for FDM, but also fits boundary easily, arranges nodal points flexibly and makes local grids fine down conveniently. The software package, which consists of EU-FEM models and pre/post-processing skills, has been widely used to estuary, near-shore, bay, lake and complex waters with many islands and channels. In addition to flow field, this model can be used to calculate the distribution fields of pollutants, temperature, salinity, sediment, and oil spill, and can be used to case study of estuary regulation projects. Some practical applications are presented and some problems discussed.展开更多
Oil and gas exploration and production is the most important and key segment in the whole business chain of the petroleum industry.Therefore,oil companies always put much emphasis on making scientific and reasonable d...Oil and gas exploration and production is the most important and key segment in the whole business chain of the petroleum industry.Therefore,oil companies always put much emphasis on making scientific and reasonable decisions about investment scale and structure in the upstream sector,so that they can minimise business risks and obtain high returns.According to the system dynamics theories and methods and based on the actual results from an oil company's practice in China,a system dynamics model is built in this paper for analyzing and forecasting the upstream investment scale and structure for an oil company.This model was used to analyze the investment effect of a large oil company in China, and the results showed that the total upstream investment scale will decline slowly in a short period and the investment proportion of different parts should be adjusted if some influencing factors are taken into account.This application practice was compared with the actual data and indicated that the system dynamics(SD) model presented in this paper is a useful tool for analyzing and forecasting of upstream investment scale and structure of oil companies in their investment decisions.展开更多
Relaxation of control over the upstream business of the petroleum industry in China is discussed. The authors suggest that a basic institutional preparation should be made before relaxing control over the upstream bus...Relaxation of control over the upstream business of the petroleum industry in China is discussed. The authors suggest that a basic institutional preparation should be made before relaxing control over the upstream business, and that the institutional preparation includes at least four parts: 1) setting up the admission standards, 2) perfecting the management system of mining rights, 3) reforming the royalty and taxation system for oil and gas resources, and 4) improving the supervision and management system. Stressing the institutional preparation before relaxation of control does not mean that China could not relax control over the upstream business until the management systems are perfected, but the authors suggest that China could establish a necessary system for relaxation of control and to improve it with future practice.展开更多
With the implementation of the production tests in permafrost and offshore regions in Canada,US,Japan,and China,the study of natural gas hydrate has progressed into the stage of technology development for industrial e...With the implementation of the production tests in permafrost and offshore regions in Canada,US,Japan,and China,the study of natural gas hydrate has progressed into the stage of technology development for industrial exploitation.The depressurization method is considered as a better strategy to produce gas from hydrate reservoirs based on production tests and laboratory experiments.Multi-well production is proposed to improve gas production efficiency,to meet the requirement for industrial production.For evaluating the applicability of multi-well production to hydrate exploitation,a 2D model is established,with numerical simulations of the performance of the multi-well pattern carried out.To understand the dissociation behavior of gas hydrate,the pressure and temperature distributions in the hydrate reservoir are specified,and the change in permeability of reservoir sediments is investigated.The results obtained indicate that multi-well production can improve the well connectivity,accelerate hydrate dissociation,enhance gas production rate and reduce water production as compared with single-well production.展开更多
All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three lar...All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three large river systems from east to west, the Shiyang, Heihe and Shule river basins. These rivers are supplied by precipitation, snowmelt and ice-melt runoff from the Qilian Mountain area. Therefore, changes of precipitation and temperature in the upstream watersheds of these rivers have an important effect on changes of mountainous runoff and reasonable utilization of water resources in this region. For this reason, the Qilian Mountain area, upstream watersheds and runoff forming areas of these rivers are chosen as the study area. The change characteristics and variation trend of temperature and precipitation in this area under the backdrop of global warming axe analyzed based on observa- tional data of relational weather and hydrologic stations in the area. Results show that temperatures in the upriver mountain areas of these three large river basins have been increasing, although the increasing degree is differentially affected by global warming. The rising extent of annual and seasonal temperatures in the upstream mountain area of the Shule river basin located in the west- em Qilian Mountains, were all largest over the past 50 years. Precipitation in the upstream mountain areas of Hexi region' three river basins located respectively in the western, middle and eastern Qilian Mountains have been presenting an increasing trend to varying degrees as a whole for more than 50 years. This means that climate in the upstream mountain areas of Hexi region' three river basins are becoming increasingly warmer and moister over the past 50 years, which will be very good for the ecological en- vironment and agricultural production in the region.展开更多
基金supported by the National Natural Science Foundation of China(31925029,31471457)the National Key Research and Development Project of China(2021YFD120010105)Guangdong Key Laboratory of New Technology in Rice Breeding(2020B1212060047)。
文摘Panicle architecture is an agronomic determinant of crop yield and a target for cereal crop improvement.To investigate its molecular mechanisms in rice,we performed map-based cloning and characterization of OPEN PANICLE 1(OP1),a gain-of-function allele of LIGULELESS 1(LG1),controlling the spread-panicle phenotype.This allele results from a 48-bp deletion in the LG1 upstream region and promotes pulvinus development at the base of the primary branch.Increased OP1 expression and altered panicle phenotype in chimeric transgenic plants and upstream-region knockout mutants indicated that the deletion regulates spread-panicle architecture in the mutant spread panicle 1(sp1).Knocking out BRASSINOSTEROID UPREGULATED1(BU1)gene in the background of OP1 complementary plants resulted in compact panicles,suggesting OP1 may regulate inflorescence architecture via the brassinosteroid signaling pathway.We regard that manipulating the upstream regulatory region of OP1 or genes involved in BR signal pathway could be an efficient way to improve rice inflorescence architecture.
基金Supported by Capital Medical University Scientific Research Grant for Undergraduate Students(No.XSKY2023026).
文摘Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual impairment.Increasing evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress of AMD,and the function of anti-oxidant capacity of PRE plays a fundamental physiological role.Nuclear factor erythroid 2 related factor 2(Nrf2)is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative genes.Its functions of protecting RPE cells against oxidative stress(OS)and ensuing physiological changes,including inflammation,mitochondrial damage and autophagy dysregulation,have already been elucidated.Understanding the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD pathogenesis.For the first time,this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis,including proteins and miRNAs,and their underlying molecular mechanisms,which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.
基金This study is supported by the National Social Science Foundation(NSSF)Project“Impact of Services Liberalization in High-quality Development Stage on Chinese Industry Upgrading(No.18AJY012).”
文摘By building a composite index for measuring national digital economy development and sectoral digital intensities,this paper derives metrics of industry-level digital economy penetration under the framework of specialization within global value chains(GVCs),systematically analyzes the mechanisms through which digital economy development affects GVCs upstreamness,and examines the moderating effect of institutional quality.The study shows that different dimensions of digital economy development significantly boost GVCs upstreamness,a conclusion that holds even after accounting for endogeneity through dynamic panel models with instrumental variables based on past data.Further research shows that technological innovation capabilities and resource allocation efficiency have gradually become important channels for digital economy development to boost GVCs upstreamness.Adding indicators on institutional quality reveals that greater institutional quality not only directly promotes GVCs upstreamness but also reinforces the impact of digital economy development on higher GVCs positioning.
基金funded by the National Key Research and Development Program(Grant No.2018YFC0807804-2)。
文摘Reservoir classification is a key link in reservoir evaluation.However,traditional manual means are inefficient,subjective,and classification standards are not uniform.Therefore,taking the Mishrif Formation of the Western Iraq as an example,a new reservoir classification and discrimination method is established by using the K-means clustering method and the Bayesian discrimination method.These methods are applied to non-cored wells to calculate the discrimination accuracy of the reservoir type,and thus the main reasons for low accuracy of reservoir discrimination are clarified.The results show that the discrimination accuracy of reservoir type based on K-means clustering and Bayesian stepwise discrimination is strongly related to the accuracy of the core data.The discrimination accuracy rate of TypeⅠ,TypeⅡ,and TypeⅤreservoirs is found to be significantly higher than that of TypeⅢand TypeⅣreservoirs using the method of combining K-means clustering and Bayesian theory based on logging data.Although the recognition accuracy of the new methodology for the TypeⅣreservoir is low,with average accuracy the new method has reached more than 82%in the entire study area,which lays a good foundation for rapid and accurate discrimination of reservoir types and the fine evaluation of a reservoir.
文摘An integrated geological-petrophysical analysis of the rudist-bearing sequence of the Cretaceous Sarvak Formation is given one giant oilfield,and provides an improved understanding of this main reservoir in the Abadan Plain,in the Zagros Basin,SW Iran.The main objective of this study is to evaluate reservoir potential of the Sarvak Formation,and then to utilize the calibrated well log signature to correlate reservoir potential in un-cored wells.Eight main facies are recognized and categorized in five facies groups:lagoon,shoal,rudist-biostrome,slope,and shallow open marine,deposited on a shelf carbonate platform.Given the distribution of diagenetic products and their effects on pore systems,three diagenetic facies namely,(DF-1)low dissolution and cementation;(DF-2);high dissolution;and(DF-3)high cementation are differentiated.The initial sedimentary characteristics in combination with distribution of diagenetic products play an important role in reservoir quality heterogeneity.The effect of diagenetic processes related to disconformities mainly depends on the facies nature below these surfaces.Grain-dominated facies of shoal and rudist debris,observed below the Cenomanian–Turonian disconformity,are mostly characterized by high dissolution and interconnected pore systems.Finally,depositional and diagenetic facies in the studied wells are correlated by petrophysical well log data,leading to distribution of the reservoir zones.Data obtained can be utilized for efficient reservoir characterization of the Sarvak Formation and its equivalent units in the Arabian Plate.
基金the National Major Project of Science and Technology in developing great oil&gas field and coal bed gas(Grant No.2016ZX05007-006)the Study on water-cut control and production stabilization in the old gasfields and efficient development in new gasfields in Qaidam Basin(Grant No.2016E-0106GF)。
文摘The bedrock weathered crust in front of the Altun Mountains in the Qaidam Basin,western China,is different from others because this is a salt-lake basin,where saline water fluid infiltrates and is deposited in the overlying strata.A large amount of gypsum infills the bedrock weathered crust,and this has changed the pore structure.Using core observation,polarized light microscopy,electron probe,physical property analysis and field emission scanning electron microscopy experiments,the characteristics of the weathered bedrock have been studied.There are cracks and a small number of dissolved pores in the interior of the weathered crust.Matrix micropores are widely developed,especially the various matrix cracks formed by tectonics and weathering,as well as the stress characteristics of small dissolved pores,and physical properties such as porosity and permeability.This‘dual structure’developed in the bedrock is important for guiding the exploration of the lake basin bedrock for natural gas.
基金financially supported by Natural Scienceof University of Jiangsu Province (Grant No.22KJB580004)the Key R&D Projects in Guangdong Province (Grant No.2020B1111500001)the Jiangsu Province“Six Talents Peak”High-Level Talents Support Project (Grant No.2018-KTHY-033)。
文摘Unsteady wash waves generated by a ship with constant speed moving across an uneven bottom topography are investigated by numerical simulations based on a Mixed Euler–Lagrange(MEL) method. The transition is accomplished by the ship traveling from the depth h1 into the depth h2 via a step bottom. A small tsunami would be created after this transition. However, the unsteady wave-making resistance induced by this new phenomenon has not been well documented by literature. Therefore, the main purpose of the present study is to quantify the effects of an uneven bottom on the unsteady wash waves and wave-making resistance acting on the ship. An upwind differential scheme is commonly used in the Euler method to deal with the convection terms under free-surface condition to prevent waves in the upstream. Evidently, it cannot be applied to the present problem due to upstream waves generated by the ship would be dampened by the upwind scheme. The central differential scheme provides more accurate results,but it is not unconditionally stable. An MEL method is therefore employed to investigate the upstream wave generated by the ship moving over the uneven bottom. Simulation results show that the hydrodynamic interaction between the ship and the uneven bottom could initiate an upstream tsunami, as well as unsteady wave-making resistance on ships.The unsteady wave-making resistance oscillates periodically, and the amplitude and period of the oscillations are highly dependent on speed and water depth.
基金the National Key Research and Development Program of China (Grant No.2017YFA0604501)the National Natural Science Foundation of China (Grant No.41475013) for the funding support
文摘We use the Wind Farm Parameterization(WFP) scheme coupled with the Weather Research and Forecasting model under multiple resolution regimes to simulate turbulent wake dynamics generated by a real onshore wind farm and their influence at the local meteorological scale. The model outputs are compared with earlier modeling and observation studies. It is found that higher vertical and horizontal resolutions have great impacts on the simulated wake flow dynamics. The corresponding wind speed deficit and turbulent kinetic energy results match well with previous studies. In addition, the effect of horizontal resolution on near-surface meteorology is significantly higher than that of vertical resolution. The wake flow field extends from the start of the wind farm to downstream within 10 km, where the wind speed deficit may exceed 4%. For a height of 150 m or at a distance of about 25 km downstream, the wind speed deficit is around 2%. This indicates that, at a distance of more than 25 km downstream, the impact of the wind turbines can be ignored. Analysis of near-surface meteorology indicates a night and early morning warming near the surface, and increase in near-surface water vapor mixing ratio with decreasing surface sensible and latent heat fluxes. During daytime, a slight cooling near the surface and decrease in the near-surface water vapor mixing ratio with increasing surface sensible and latent heat fluxes is noticed over the wind farm area.
基金National Natural Science Foundation of China, No.40371018
文摘This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,000 scale digital map, six factors including slope angle, rainstorm days, buffer of river channels, maximum runoff discharge of standard area, debris flow distribution density and flood disaster history were analyzed and superimposed to create the torrent risk evaluation map. Population density, farmland percentage, house property, and GDP as indexes accounting for torrent hazards were analyzed in terms of vulnerability mapping. Torrent risk zonation by means of GIS was overlaid on the two data layers of hazard and vulnerability. Then each grid unit with a resolution of 500 m- 500 m was divided into four categories of the risk: extremely high, high, moderate and low. Finally the same level risk was combined into a confirmed zone, which represents torrent risk of the study area. The risk evaluation result in the upper Red River Basin shows that the extremely high risk area of 13,150 km^2 takes up 17.9% of the total inundated area, the high risk area of 33,783 km^2 is 45.9%, the moderate risk area of 18,563 km^2 is 25.2% and the low risk area of 8115 km^2 is 11.0%.
基金supported jointly by the China Geological Survey project(grant number:1212011120167,12120114002201)China National Natural Science Foundation(grant number 41472178)
文摘We present in this paper some new evidence for the change during the Quaternary in kinematics of faults cutting the eastern margin of the Tibetan Plateau. It shows that significant shortening deformation occurred during the Early Pleistocene, evidenced by eastward thrusting of Mesozoic carbonates on the Pliocene lacustrine deposits along the Minjiang upstream fault zone and by development of the transpressional ridges of basement rocks along the Anninghe river valley. The Middle Pleistocene seems to be a relaxant stage with local development of the intra-mountain basins particularly prominent along the Minjiang Upstream and along the southern segment of the Anninghe River Valley. This relaxation may have been duo to a local collapse of the thickened crust attained during the late Neogene to early Pleistocene across this marginal zone. Fault kinematics has been changed since the late Pleistocene, and was predominated by reverse sinistral strike-slip along the Minshan Uplift, reverse dextral strike-slip on the Longmenshan fault zone and pure sinistral strike-slip on the Anninghe fault. This change in fault kinematics during the Quaternary allows a better understanding of the mechanism by which the marginal ranges of the plateau has been built through episodic activities.
基金supported by the Natural Science Foundation of Jiangsu Higher Education Institutions of China(Major Program),No.16KJA310005(to SYL)the Natural Science Foundation of Nantong City of China,No.JC2018058(to TMQ)the Priority Academic Program Development of Jiangsu Higher Education Institutions of China
文摘The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regeneration.Our previous study observed the dynamic changes of genes in L4–6 dorsal root ganglion after rat sciatic nerve crush using transcriptome sequencing.Our current study focused on upstream growth factors and found that a total of 19 upstream growth factors were dysregulated in dorsal root ganglions at 3,9 hours,1,4,or 7 days after nerve crush,compared with the 0 hour control.Thirty-six rat models of sciatic nerve crush injury were prepared as described previously.Then,they were divided into six groups to measure the expression changes of representative genes at 0,3,9 hours,1,4 or 7 days post crush.Our current study measured the expression levels of representative upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin genes,and explored critical signaling pathways and biological process through bioinformatic analysis.Our data revealed that many of these dysregulated upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin,participated in tissue remodeling and axon growth-related biological processes Therefore,the experiment described the expression pattern of upstream growth factors in the dorsal root ganglia after peripheral nerve injury.Bioinformatic analysis revealed growth factors that may promote repair and regeneration of damaged peripheral nerves.All animal surgery procedures were performed in accordance with Institutional Animal Care Guidelines of Nantong University and ethically approved by the Administration Committee of Experimental Animals,China(approval No.20170302-017)on March 2,2017.
基金the National Key R&D Program of China(2019YFD1001400)the China Agriculture Research System(CARS 28-45).
文摘Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator of leaf and flower senescence,but the molecular mechanism of ethylene-induced ovule senescence has not yet been elucidated.In this study,we found that blockage of fertilization caused ovule abortion in the pear cultivar‘1913’.According to transcriptome and phytohormone content data,ethylene biosynthesis was activated by pollination.At the same time,ethylene overaccumulated in ovules,where cells were sensitive to ethylene signals in the absence of fertilization.We identified a transcription factor in the ethylene signal response,ethylene-insensitive 3-like(EIL1),as a likely participant in ovule senescence.Overexpression of PbEIL1 in tomato caused precocious onset of ovule senescence.We further found that EIL1 could directly bind to the promoter of the SENESCENCE-ASSOCIATED CYSTEINE PROTEINASE 1(PbCysp1)gene and act upstream of senescence.Yeast one-hybrid and dual-luciferase assays revealed the interaction of the transcription factor and the promoter DNA sequence and demonstrated that PbEIL1 enhanced the action of PbCysp1.Collectively,our results provide new insights into how ethylene promotes the progression of unfertilized ovule senescence.
基金This project was supported by grants from the National Key Research and Development Program of China(2018YFD1000200)the National Natural Science Foundation of China(32122080,31972375,31902049)Shandong Province(ZR2020YQ25).
文摘In fleshy fruits,organic acids are the main source of fruit acidity and play an important role in regulating osmotic pressure,pH homeostasis,stress resistance,and fruit quality.The transport of organic acids from the cytosol to the vacuole and their storage are complex processes.A large number of transporters carry organic acids from the cytosol to the vacuole with the assistance of various proton pumps and enzymes.However,much remains to be explored regarding the vacuolar transport mechanism of organic acids as well as the substances involved and their association.In this review,recent advances in the vacuolar transport mechanism of organic acids in plants are summarized from the perspectives of transporters,channels,proton pumps,and upstream regulators to better understand the complex regulatory networks involved in fruit acid formation.
文摘The Explicit Upstream FEM (EU-FEM) proposed in this paper not only possesses the advantages of saving memory and CPU time for FDM, but also fits boundary easily, arranges nodal points flexibly and makes local grids fine down conveniently. The software package, which consists of EU-FEM models and pre/post-processing skills, has been widely used to estuary, near-shore, bay, lake and complex waters with many islands and channels. In addition to flow field, this model can be used to calculate the distribution fields of pollutants, temperature, salinity, sediment, and oil spill, and can be used to case study of estuary regulation projects. Some practical applications are presented and some problems discussed.
文摘Oil and gas exploration and production is the most important and key segment in the whole business chain of the petroleum industry.Therefore,oil companies always put much emphasis on making scientific and reasonable decisions about investment scale and structure in the upstream sector,so that they can minimise business risks and obtain high returns.According to the system dynamics theories and methods and based on the actual results from an oil company's practice in China,a system dynamics model is built in this paper for analyzing and forecasting the upstream investment scale and structure for an oil company.This model was used to analyze the investment effect of a large oil company in China, and the results showed that the total upstream investment scale will decline slowly in a short period and the investment proportion of different parts should be adjusted if some influencing factors are taken into account.This application practice was compared with the actual data and indicated that the system dynamics(SD) model presented in this paper is a useful tool for analyzing and forecasting of upstream investment scale and structure of oil companies in their investment decisions.
文摘Relaxation of control over the upstream business of the petroleum industry in China is discussed. The authors suggest that a basic institutional preparation should be made before relaxing control over the upstream business, and that the institutional preparation includes at least four parts: 1) setting up the admission standards, 2) perfecting the management system of mining rights, 3) reforming the royalty and taxation system for oil and gas resources, and 4) improving the supervision and management system. Stressing the institutional preparation before relaxation of control does not mean that China could not relax control over the upstream business until the management systems are perfected, but the authors suggest that China could establish a necessary system for relaxation of control and to improve it with future practice.
基金This work is funded by the Ministry of Science and Technology of the People's Republic of China(Grant No.2017YFC0307603)the China Geological Survey(Grant No.DD20190234 and HD-JJHT-20).
文摘With the implementation of the production tests in permafrost and offshore regions in Canada,US,Japan,and China,the study of natural gas hydrate has progressed into the stage of technology development for industrial exploitation.The depressurization method is considered as a better strategy to produce gas from hydrate reservoirs based on production tests and laboratory experiments.Multi-well production is proposed to improve gas production efficiency,to meet the requirement for industrial production.For evaluating the applicability of multi-well production to hydrate exploitation,a 2D model is established,with numerical simulations of the performance of the multi-well pattern carried out.To understand the dissociation behavior of gas hydrate,the pressure and temperature distributions in the hydrate reservoir are specified,and the change in permeability of reservoir sediments is investigated.The results obtained indicate that multi-well production can improve the well connectivity,accelerate hydrate dissociation,enhance gas production rate and reduce water production as compared with single-well production.
基金supported by the Open Foundation of Key Laboratory of Ecohydrology in Inland River Basin, Chinese Academy of Sciences and National Nature Science Foundation of China (No. 9112502)The Coupling and Modeling of Eco-hydrological Processes in the Upper Reaches of Heihe River (No. 91225302)+1 种基金Research of Eco-hydrological Response Units in Heihe River Basin Based on the Method of Concept Lattice (No. 41240002)System Behaviors and Regulation of Ecohydrological Processes in the Middle and Lower Heihe River Basin (91225301)
文摘All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three large river systems from east to west, the Shiyang, Heihe and Shule river basins. These rivers are supplied by precipitation, snowmelt and ice-melt runoff from the Qilian Mountain area. Therefore, changes of precipitation and temperature in the upstream watersheds of these rivers have an important effect on changes of mountainous runoff and reasonable utilization of water resources in this region. For this reason, the Qilian Mountain area, upstream watersheds and runoff forming areas of these rivers are chosen as the study area. The change characteristics and variation trend of temperature and precipitation in this area under the backdrop of global warming axe analyzed based on observa- tional data of relational weather and hydrologic stations in the area. Results show that temperatures in the upriver mountain areas of these three large river basins have been increasing, although the increasing degree is differentially affected by global warming. The rising extent of annual and seasonal temperatures in the upstream mountain area of the Shule river basin located in the west- em Qilian Mountains, were all largest over the past 50 years. Precipitation in the upstream mountain areas of Hexi region' three river basins located respectively in the western, middle and eastern Qilian Mountains have been presenting an increasing trend to varying degrees as a whole for more than 50 years. This means that climate in the upstream mountain areas of Hexi region' three river basins are becoming increasingly warmer and moister over the past 50 years, which will be very good for the ecological en- vironment and agricultural production in the region.