Through analysis of four aspects,including the distribution and production of global oil and gas fields,the distribution and changes of remaining recoverable reserves,the differences in oil and gas production between ...Through analysis of four aspects,including the distribution and production of global oil and gas fields,the distribution and changes of remaining recoverable reserves,the differences in oil and gas production between regions/countries,and the development potential of oil and gas fields with production capacity not built and to be built,this paper presents the situation and trends of global oil and gas development in 2022.It is found that,in 2022,oil and gas fields are widely distributed worldwide,and upstream production activities continue to recover;the oil and gas reserves decrease slightly year on year,and the oil and gas reserves in sea areas increase significantly;the oil and gas production increases continuously,and the key resource countries make a significant contribution in oil and gas production growth;the oil and gas fields with production capacity not built and to be built hold abundant reserves,and their development potential will be gradually released with the economic benefits increase.Further analysis is conducted from the perspectives of global oil and gas resources continuity,geopolitical risks,potential of international cooperation,and upgrade of unconventional oil and gas technology.Finally,in view of core business domains and strategies under the new situation,the Chinese oil companies are recommended to:(1)keep a foothold in onshore conventional oil and gas development by virtue of their comparative advantages and learning from other’s experience in cooperation;(2)carry out pilot tests on development adjustment,and deepen the international cooperation in enhanced oil/gas recovery;(3)improve the oil and gas operation capabilities in sea areas to transform from follower as minority shareholder to joint venture and then to independent operations;and(4)seek appropriate ways for shale oil/gas development to reduce the dependence on foreign oil and gas.展开更多
[Objective] The aim was to make analysis on natural condition,present situation,and potential of rice production development in Angola.[Method] Conclusion and analysis of rice development in Angola were conducted from...[Objective] The aim was to make analysis on natural condition,present situation,and potential of rice production development in Angola.[Method] Conclusion and analysis of rice development in Angola were conducted from natural condition,production status,present problem and development potential.[Result] In Angola,about 30 million hectares agricultural lands enjoy fresh water,temperature,and light resources which are requirement for rice development.Presently,however,some disadvantages have harassed the nation,such as outdated production mode and technology,small cultivated area and low level of per unit yield.In addition,about 98% of consumed rice was imported from other countries.The government has attached high importance to food production,and rice production was a priority of national investment.Per unit rice yield would achieve 7 500 kg/hm2 if Angola introduces hybrid rice species and high-yield cultivation techniques from China.[Conclusion] The research provided technical reference for enterprises or individuals ready to invest in rice development in Angola.展开更多
Based on the characteristics of agricultural resources and social resources in Shandong Province, the approaches of developing farming system potential were discussed, which provide important references for sustainabl...Based on the characteristics of agricultural resources and social resources in Shandong Province, the approaches of developing farming system potential were discussed, which provide important references for sustainable development of modern farming system.展开更多
The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 (PZM-3) and North Carolina State University-23 (NCSU-23) media was investigated. After in vitro maturation oocytes were elect...The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 (PZM-3) and North Carolina State University-23 (NCSU-23) media was investigated. After in vitro maturation oocytes were electro-activated, and the subsequent developmental competence, rates of apoptotic, fragmented and arrested embryos from the two media were evaluated. Also, the ratio of mRNA expression of Bcl-2 and Bax gene was determined. Results demonstrated that cleavage, blastocyst, hatched blastocyst rates, and blastocyst cell numbers were significantly higher in PZM-3 than in NCSU-23. The rate of fragmented embryos in PZM-3 was lower than in NCSU-23 on d 1 and 3 (P〈0.05) while the percentage of arrested embryo was lower in PZM-3 than in NCSU-23 on d 4 and 5 (P〈0.05). TUNEL positive signals were higher in NCSU-23 than in PZM-3 from d 3 to 7 (P〈0.05). The ratios of Bcl-2 and Bax mRNA expression in embryos were higher on d 5 than on d 3 and 1 in PZM-3 (P〈0.05). In contrast, the ratios of Bcl-2 and Bax mRNA expression in embryos on d 1 were higher than on d 3 and 5 in NCSU-23 (P〈0.05). Additionally, the ratios of Bcl-2 and Bax mRNA expression in embryos in PZM-3 were higher than in NCSU-23 on d 3 and 5 (P〈0.05). In conclusion, lower apoptotic embryo rates and down-regulating Bax together with up-regulating expression of Bcl-2 transcripts may be responsible for the better developmental competence of porcine parthenotes in PZM-3.展开更多
With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy re...With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy resources as alternatives to conventional sources to support this energy transition.In this regard,analyzing the“location,”“quantity,”and“quality”of global solar energy resources will not only assist an individual country to efficiently utilize these resources but also promote the realization of large-scale intercontinental resource utilization and complementation.This study established the basic database,model methods,and platform tools for global solar energy assessment,Then,a global solar energy resource assessment was conducted,which included the theoretical reserves(TRs),technical installed potential capacity(TPIC),and average development cost(ADC).A comparative analysis of the assessment results for all continents was also performed.After that,based on big data analysis and geographic information system(GIS)calculations,the distribution characteristics of the global solar power TPIC were calculated with the two core indicators,namely the capacity factor and ADC.Furthermore,a data-driven quantitative evaluation of the refined development potential of solar energy resources was performed.Finally,the reasonableness and coincidence analysis of the resource assessment results were verified using data from global and specifically Chinese photovoltaic(PV)bases.展开更多
By analyzing the distribution of global oil and gas fields and the reasons why some oil and gas fields are not in production, the distribution characteristics of oil and gas remaining recoverable reserves and their ye...By analyzing the distribution of global oil and gas fields and the reasons why some oil and gas fields are not in production, the distribution characteristics of oil and gas remaining recoverable reserves and their year-on-year changes, the distribution characteristics of oil and gas production and their year-on-year changes, and the development potential of oil and gas to be tapped in 2021, this paper sorts out systematically the current status and characteristics of global oil and gas development, summaries the major trends of global oil and gas development, puts forward enlightenment for international oil and gas cooperation. In 2021, oil and gas fields were widely distributed, the number of non-producing oil and gas fields was large;the whole oil and gas remaining recoverable reserves declined slightly, unconventional oil and gas remaining recoverable reserves dropped significantly;the overall oil and gas production continuously increased, the outputs of key resource-host countries kept year-on-year growth;undeveloped oilfields had abundant reserves and great development potential. Combined with global oil and gas geopolitics, oil and gas industry development trends, oil and gas investment intensity, and the tracking and judgment of hotspot fields, the major trends of global oil and gas development in 2021 are summarized. On this basis, the four aspects of enlightenment and suggestions for international oil and gas cooperation and development strategies are put forward: attach great importance to the obligation of marine abandonment to ensure high-quality and long-term benefit development of offshore oil and gas;adhere to the principle of not going to dangerous and chaotic places, strengthen the concentration of oil and gas assets, and establish multi stable supply bases;based on the multi-scenario demand of natural gas, realize the transformation from integrated collaboration to full oil and gas industry chain development;increase the acquisition of high-quality large-scale assets, and pay attention to the continuous optimization of the shareholding ratio of projects at different stages.展开更多
With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digi...With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digital divide and narrow the regional gap,providing continuous impetus to further promote economic development. Here, we considered 31 provincial-level administrative units in China(not including Hong Kong, Macao, and Taiwan of China due to data unavailable) and established comprehensive evaluation indicators for the development potential of NIC. Afterward, we used the entropy-weight TOPSIS model to determine the development potential of NIC and analyze its spatio-temporal evolution characteristics. Furthermore, the GeoDetector model was applied to explore the driving mechanism of the NIC development potential. The conclusions were as follows: (1) The Chinese NIC development potential is generally low. The eastern China was the region with the highest development potential year by year, while the development potential in the central China was found to be in an accelerating phase. (2) The evolution of the Chinese NIC development potential’s spatial pattern has been characterized by an inland extension and coastal agglomeration. Moreover, we identified a superior development zone, a rising development zone, an inferior development zone, and a declining development zone. (3) The scope of Chinese NIC development potential agglomeration areas has gradually expanded and its degree has gradually deepened. The range of high-value agglomeration in eastern area gradually expanded and its degree gradually deepened. (4) Investment in innovative talents appears as the core factor affecting the Chinese NIC development potential. Whether acting alone or synergistically with other factors, its promoting effect on Chinese NIC development potential is the strongest.展开更多
To investigate the relationship between the ATP content in human oocytes and the deve-lopmental potential of human oocytes, unfertilized oocytes from clinical IVF and immature oocytes unsuitable for ICSI were collecte...To investigate the relationship between the ATP content in human oocytes and the deve-lopmental potential of human oocytes, unfertilized oocytes from clinical IVF and immature oocytes unsuitable for ICSI were collected. The ATP content of these unfertilized and in vitro matured eggs were determined quantitatively by measuring the luminescence using an ATP-dependent bioluminescence assay. The result showed that the ATP content of unfertilized oocytes was higher than in vitro matured ones (2.20±0.67 pmol vs 1.72±0.49 pmol, P<0.05 ). In unfertilized oocytes, the ATP content of those whose fertilization rates (FR) was higher than 50 % was 2.43±0.60 pmol, which was significantly different from those whose FR was less than 50 % (1.72±0.56 pmol), while in in vitro matured oocytes, the ATP content of those whose FR more than 50 % was 1.8±0.44 pmol, slightly higher than those less than 50 % (1.55±0.40 pmol), without statistical significance. There was a tendency that the ATP content of oocytes of pregnant patients was higher than those of controls, but the sample number was too small to show any significance in statistics. Briefly, there was positive correlation between the ATP content in oocytes and developmental potential of oocytes.展开更多
Microorganisms, regardless of whether pathogenic or not, may cause enormous economic losses due to adverse effects on human and animal health, or by damaging the quality of the agricultural and food products. Based on...Microorganisms, regardless of whether pathogenic or not, may cause enormous economic losses due to adverse effects on human and animal health, or by damaging the quality of the agricultural and food products. Based on these effects, the development of prompt molecular methods and their involvement in the practical pathogen diagnostic diagnostics is more than actual. This paper is focused on the evaluation of easy-to-perform and highly budget-friendly, PCR-related DNA purification protocols for diagnostic purposes especially in water or similar simple matrices. The slight modifications of earlier described DNA isolation methods, which rely on chelate exchange resin and/or ethanol-sodium-based heat lysis, we reevaluated in comparison with a widely used commercial kit. The efficiency of DNA purification techniques was assessed from Gramnegative as well as Gram-positive bacteria and yeast using quantitative PCR. The effectivity of different methods tested may vary depending on the bacterial or yeast species in question. Nevertheless, in our hands, the chelate exchange resin-based methods were found to be the most robust and/or satisfying at least by an acceptable reproducibility rate. Our presented results support the potential of low-cost but still sensitive molecular microbe detection procedures consisting of only a few pipetting steps resulting in good reproducibility and the least possible environmental burden, serving as a good starting point for developments of matrix-specific processes and methods.展开更多
With the objectives to acquire the fundamental dat a of the territorial resource, understand the impacts of human activit ies on the land use and cover patterns and evaluate the potential of the future exploitation, a...With the objectives to acquire the fundamental dat a of the territorial resource, understand the impacts of human activit ies on the land use and cover patterns and evaluate the potential of the future exploitation, an intensive land cover classification with an accuracy of 93% has been completed for North Ningxia by remote sen sing technique based on the adoption of a combination method composed o f texture training, maximum likelihood classification and post-processing such as re-allocation and aggregation. This classification result was incorporated with the contemporaneous socio-economic and meteorological d ata for cross-sectional regression modelling to reveal the spatial dete rminants of the land cover patterns and understand the human-environmen tal relationships. A tentative evaluation on the potential of soil exp loitation in the near future was carried out in combination with our land use and cover change detection results aiming at supplying some useful references for the central and local governments in their sustainable l and use planning.展开更多
The containerized traffic has come into being for over forty years and has become the most important mode of sea transportation. Although containerized traffic trade has been developed in port cities of Dalian, Yingko...The containerized traffic has come into being for over forty years and has become the most important mode of sea transportation. Although containerized traffic trade has been developed in port cities of Dalian, Yingkou, Dandong and Jinzhou in Liaoning Province, yet their development sped are obviously slower than the entire national development pace. In the article, the authors make a systematic study on the current situation and the potential developmental possibility of containerized traffic in Liaoning Province. It is held that the relative low proportion of the supply of goods in hinterland is relative low which will restrict directly the development potentiality of the container harbors in Liaoning. Three countermeasures of the containerized traffic development were given accordingly.展开更多
This paper describes the significance of irrigation on economy development and the status of irrigation development in Tanzania, analyzing the potential and advantages of irrigation development in this country, combin...This paper describes the significance of irrigation on economy development and the status of irrigation development in Tanzania, analyzing the potential and advantages of irrigation development in this country, combined with the major initiatives and experiences which can learn from in the recent 30 years of rural water conservancy in China. Then it discusses the next investment focus on irrigation development for Tanzanian.展开更多
Rural revitalization strategy is an important strategic layout of rural development in the new era of the CPC Central Committee,and scientific and reasonable determination of village types is an important measure to p...Rural revitalization strategy is an important strategic layout of rural development in the new era of the CPC Central Committee,and scientific and reasonable determination of village types is an important measure to promote rural revitalization by classification.The villages of Wan’an County were selected as the research object.Firstly,the factors that have a key impact on the development of the villages were extracted and qualitatively analyzed to preliminarily screen and judge their types.Secondly,the evaluation index system of development potential of the villages was constructed to quantitatively evaluate and reasonably classify the villages.Finally,the spatial distribution characteristics and quantity of different villages were revealed,and differentiated development strategies were proposed.展开更多
Yuan Longping proposed that smash-ridging technology could be extend-ed widely nationwide. ln the research, smash-ridging technology reconstruct cultiva-tion layers with loose soils in agricultural fields, creating "...Yuan Longping proposed that smash-ridging technology could be extend-ed widely nationwide. ln the research, smash-ridging technology reconstruct cultiva-tion layers with loose soils in agricultural fields, creating "4453" effects, as fol ows: "Four increases" include to increase loosen soil quantity in cultivation layers, soil nutri-ents use, "water pool" in soils, and "oxygen pool" in soils. Four reductions are to reduce soil erosion, carbon emission, salt content and heavy metal in soils. Five resistances refer to improve crop resistance capacity in terms of drought, high tem-perature, lower temperature, disease and lodging. Three improvements indicate to enhance photosynthetic efficiency over 10%, yield in 10%-30% and quality over 5%. lt is researched that without additional chemical fertilizer, yield could increase by 10% by labor force, animal, tractor or smash-ridging machine. What’s more, by smash-ridging cultivation, the depth can be 20 times or higher compared with tractor cultivation, with looser soils. lt is estimated that if smash-ridging cultivation is applied once in agricultural lands in China, present soil layers can be twice as deep as present. Specifical y, the thickness of loose soil-layers could be extended from 10-18 cm at present to 25-35 cm, and natural rainfal would increase by 40 bil ion cm3. After vitalization of soil nutrients, chemical fertilizer would decrease by 7 bil ion kg, and the increased c rops would feed more than 300 mil ion population as per yield at 7 50 kg/hm2.展开更多
The research reviewed biological characters and nutritional value of Chenopodium quinoa and concluded status quo of domestic cultivation and problems at promotion, as wel as application prospect in order to provide re...The research reviewed biological characters and nutritional value of Chenopodium quinoa and concluded status quo of domestic cultivation and problems at promotion, as wel as application prospect in order to provide references for re-search and development of Chenopodium quinoa.展开更多
Traditional music is an important component of cultural heritage.However,studies have scarcely explored the tourism development potential and the obstacle factors of traditional music.This study takes Xiangxi as the r...Traditional music is an important component of cultural heritage.However,studies have scarcely explored the tourism development potential and the obstacle factors of traditional music.This study takes Xiangxi as the research site,constructs an evaluation index system,and utilizes survey and geographical methods.The major research results are as follows:First,the average potential of resource endowment,tourism industry development,and socio-economic conditions are 0.28,0.36,and 0.24,respectively.The potential of resource endowment is higher in the west and lower in the east,that of tourism industry development is higher in the north and south and lower in the center,and that of socio-economic conditions is higher in the south and lower in the north.Second,the comprehensive potential is 0.29,which is higher in the northwest and southwest regions.Coordination in most administrative units is at a medium level,and most regions have obvious advantages in resource endowment.Third,the primary obstacle factor is socio-economic conditions(39.21%),followed by resource endowment(30.73%)and tourism industry development(30.06%).The administrative units can be classified into four groups:socio-economic condition obstacle,resource endowment and tourism industry development obstacles,resource endowment and socio-economic condition obstacles,and tourism industry development and socio-economic condition obstacles.The highest priority goals for Xiangxi involve economic development and the integration of modern technologies to stimulate passenger flow.For reg traditional music items(eastern area of Xiangxi),tourism development should be restrained and other resources with stronger inherent advantages should be exploited.This study explored the quantification of traditional music tourism potential,representing a novel breakthrough in this field of research.The indicator system and research methods used in this study can provide guidance and methodological references for cultural heritage research.The suggestions proposed in this article contribute to the rational development and effective protection of cultural heritage resources and the healthy development of the tourism industry.展开更多
Chemically defined medium is widely used for culturing mouse embryonic stem cells(mESCs),in which N2B27 works as a substitution for serum,and GSK3βand MEK inhibitors(2i)help to promote ground-state pluripo-tency.Howe...Chemically defined medium is widely used for culturing mouse embryonic stem cells(mESCs),in which N2B27 works as a substitution for serum,and GSK3βand MEK inhibitors(2i)help to promote ground-state pluripo-tency.However,recent studies suggested that MEKi might cause irreversible defects that compromise the developmental potential of mESCs.Here,we demon-strated the deficient bone morphogenetic protein(BMP)signal in the chemically defined condition is one of the main causes for the impaired pluripotency.Mechanisti-cally,activating the BMP signal pathway by BMP4 could safeguard the chromosomal integrity and proliferation capacity of mESCs through regulating downstream tar-gets Ube2s and Chmp4b.More importantly,BMP4 pro-motes a distinct in vivo developmental potential and a long-term pluripotency preservation.Besides,the pluripotent improvements driven by BMP4 are superior to those by attenuating MEK suppression.Taken together,our study shows appropriate activation of BMP signal is essential for regulating functional pluripotency and reveals that BMP4 should be applied in the serum-free culture system.展开更多
In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of ...In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of target genes. It has long been known that this process is irreversible and the terminal differentiated adult cells, such as cardiac myocytes and neurons, will not divide and differentiate. But recent reports on the two hottest fields - cloning medicine and stem cell biology doubted these concepts. This may lead to a further understanding of the potentiality of mammal development and may provide great chances for commercial and clinical practice.展开更多
Through analysis of the connotation of unconventional hydrocarbons,the source-reservoir assemblages of unconventional hydrocarbons are divided into three types,i.e.,source-reservoir neighboring type,source-reservoir i...Through analysis of the connotation of unconventional hydrocarbons,the source-reservoir assemblages of unconventional hydrocarbons are divided into three types,i.e.,source-reservoir neighboring type,source-reservoir integration type,and source-reservoir separation type.The source-reservoir neighboring type resources mainly include tight oil and tight gas with the following formation conditions and characteristics:(1)efficient near-source accumulation close to high-quality source rocks with the pressure difference between source and reservoir as the dynamic force;(2)large-area tight reservoirs with certain porosity,dominated by micro-nanopores of inorganic origin;(3)distributed in depressions and slopes with large hydrocarbon-bearing area and great resource quantity,low abundance and local development of“sweet spots”;(4)weak tectonism.The source-reservoir integration type resources mainly include coalbed methane,shale gas,shale oil and oil shale.The formation conditions and characteristics are:(1)high abundance of organic matter,different types of organic matter and thermal evolution grades leading to formation of different resources types;(2)organic-rich sections are distributed continuously in the reservoiring space which is dominated by nanometer organic pores,interparticle pores and microfissures;(3)hydrocarbons mainly occur in free or adsorbed state,varying much with resource type;(4)the resources are self-conserved,and enriched in depressions and slopes,the conservation conditions are controlled by tectonics,temperature and pressure;(5)the production per well can be enhanced by volume fracturing,which increases the permeability of the reservoirs.The source-reservoir separation type resources are more special,mainly including(1)transformed conventional resources such as oil sand and heavy oil;(2)unsteady resources formed under special conditions of temperature and pressure,among which natural gas hydrate is a representative.These three types of resources in China are different in both development prospect and current situation:(1)the source-reservoir neighboring type is most practical and will develop fast in the next 5 years;(2)the source-reservoir integration type needs continuous exploration and technical breakthrough,and is expected to develop rapidly in the coming decade;(3)in the source-reservoir separation type resources,natural gas hydrates have the greatest development potential,on which technical tests are being conducted.展开更多
基金Supported by the PetroChina Science and Technology Project(2021DJ3205).
文摘Through analysis of four aspects,including the distribution and production of global oil and gas fields,the distribution and changes of remaining recoverable reserves,the differences in oil and gas production between regions/countries,and the development potential of oil and gas fields with production capacity not built and to be built,this paper presents the situation and trends of global oil and gas development in 2022.It is found that,in 2022,oil and gas fields are widely distributed worldwide,and upstream production activities continue to recover;the oil and gas reserves decrease slightly year on year,and the oil and gas reserves in sea areas increase significantly;the oil and gas production increases continuously,and the key resource countries make a significant contribution in oil and gas production growth;the oil and gas fields with production capacity not built and to be built hold abundant reserves,and their development potential will be gradually released with the economic benefits increase.Further analysis is conducted from the perspectives of global oil and gas resources continuity,geopolitical risks,potential of international cooperation,and upgrade of unconventional oil and gas technology.Finally,in view of core business domains and strategies under the new situation,the Chinese oil companies are recommended to:(1)keep a foothold in onshore conventional oil and gas development by virtue of their comparative advantages and learning from other’s experience in cooperation;(2)carry out pilot tests on development adjustment,and deepen the international cooperation in enhanced oil/gas recovery;(3)improve the oil and gas operation capabilities in sea areas to transform from follower as minority shareholder to joint venture and then to independent operations;and(4)seek appropriate ways for shale oil/gas development to reduce the dependence on foreign oil and gas.
基金Supportd by Science and Technology Cooperation Project of Anhui Science and Technology Department (11030603031)~~
文摘[Objective] The aim was to make analysis on natural condition,present situation,and potential of rice production development in Angola.[Method] Conclusion and analysis of rice development in Angola were conducted from natural condition,production status,present problem and development potential.[Result] In Angola,about 30 million hectares agricultural lands enjoy fresh water,temperature,and light resources which are requirement for rice development.Presently,however,some disadvantages have harassed the nation,such as outdated production mode and technology,small cultivated area and low level of per unit yield.In addition,about 98% of consumed rice was imported from other countries.The government has attached high importance to food production,and rice production was a priority of national investment.Per unit rice yield would achieve 7 500 kg/hm2 if Angola introduces hybrid rice species and high-yield cultivation techniques from China.[Conclusion] The research provided technical reference for enterprises or individuals ready to invest in rice development in Angola.
基金Supported by the Scientific Research Project of Public Welfare Industry(Agriculture)(201103001)the Domestic Visiting Scholar Program for Excellent Young Teachers of Shandong Province 2009~~
文摘Based on the characteristics of agricultural resources and social resources in Shandong Province, the approaches of developing farming system potential were discussed, which provide important references for sustainable development of modern farming system.
基金funded by the National Natural Science Foundation of China (31072031)the Key Research Program of Ministry of Education of China(109018)
文摘The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 (PZM-3) and North Carolina State University-23 (NCSU-23) media was investigated. After in vitro maturation oocytes were electro-activated, and the subsequent developmental competence, rates of apoptotic, fragmented and arrested embryos from the two media were evaluated. Also, the ratio of mRNA expression of Bcl-2 and Bax gene was determined. Results demonstrated that cleavage, blastocyst, hatched blastocyst rates, and blastocyst cell numbers were significantly higher in PZM-3 than in NCSU-23. The rate of fragmented embryos in PZM-3 was lower than in NCSU-23 on d 1 and 3 (P〈0.05) while the percentage of arrested embryo was lower in PZM-3 than in NCSU-23 on d 4 and 5 (P〈0.05). TUNEL positive signals were higher in NCSU-23 than in PZM-3 from d 3 to 7 (P〈0.05). The ratios of Bcl-2 and Bax mRNA expression in embryos were higher on d 5 than on d 3 and 1 in PZM-3 (P〈0.05). In contrast, the ratios of Bcl-2 and Bax mRNA expression in embryos on d 1 were higher than on d 3 and 5 in NCSU-23 (P〈0.05). Additionally, the ratios of Bcl-2 and Bax mRNA expression in embryos in PZM-3 were higher than in NCSU-23 on d 3 and 5 (P〈0.05). In conclusion, lower apoptotic embryo rates and down-regulating Bax together with up-regulating expression of Bcl-2 transcripts may be responsible for the better developmental competence of porcine parthenotes in PZM-3.
基金supported by National Science and Technology Major Project(2018YFB0904000).
文摘With the increasing severity of environmental problems,many countries have set energy transition targets to promote the realization of the Paris Agreement.There has been a global consensus on utilizing solar energy resources as alternatives to conventional sources to support this energy transition.In this regard,analyzing the“location,”“quantity,”and“quality”of global solar energy resources will not only assist an individual country to efficiently utilize these resources but also promote the realization of large-scale intercontinental resource utilization and complementation.This study established the basic database,model methods,and platform tools for global solar energy assessment,Then,a global solar energy resource assessment was conducted,which included the theoretical reserves(TRs),technical installed potential capacity(TPIC),and average development cost(ADC).A comparative analysis of the assessment results for all continents was also performed.After that,based on big data analysis and geographic information system(GIS)calculations,the distribution characteristics of the global solar power TPIC were calculated with the two core indicators,namely the capacity factor and ADC.Furthermore,a data-driven quantitative evaluation of the refined development potential of solar energy resources was performed.Finally,the reasonableness and coincidence analysis of the resource assessment results were verified using data from global and specifically Chinese photovoltaic(PV)bases.
基金Scientific Research and Technology Development Project(2021DJ3205)。
文摘By analyzing the distribution of global oil and gas fields and the reasons why some oil and gas fields are not in production, the distribution characteristics of oil and gas remaining recoverable reserves and their year-on-year changes, the distribution characteristics of oil and gas production and their year-on-year changes, and the development potential of oil and gas to be tapped in 2021, this paper sorts out systematically the current status and characteristics of global oil and gas development, summaries the major trends of global oil and gas development, puts forward enlightenment for international oil and gas cooperation. In 2021, oil and gas fields were widely distributed, the number of non-producing oil and gas fields was large;the whole oil and gas remaining recoverable reserves declined slightly, unconventional oil and gas remaining recoverable reserves dropped significantly;the overall oil and gas production continuously increased, the outputs of key resource-host countries kept year-on-year growth;undeveloped oilfields had abundant reserves and great development potential. Combined with global oil and gas geopolitics, oil and gas industry development trends, oil and gas investment intensity, and the tracking and judgment of hotspot fields, the major trends of global oil and gas development in 2021 are summarized. On this basis, the four aspects of enlightenment and suggestions for international oil and gas cooperation and development strategies are put forward: attach great importance to the obligation of marine abandonment to ensure high-quality and long-term benefit development of offshore oil and gas;adhere to the principle of not going to dangerous and chaotic places, strengthen the concentration of oil and gas assets, and establish multi stable supply bases;based on the multi-scenario demand of natural gas, realize the transformation from integrated collaboration to full oil and gas industry chain development;increase the acquisition of high-quality large-scale assets, and pay attention to the continuous optimization of the shareholding ratio of projects at different stages.
文摘With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digital divide and narrow the regional gap,providing continuous impetus to further promote economic development. Here, we considered 31 provincial-level administrative units in China(not including Hong Kong, Macao, and Taiwan of China due to data unavailable) and established comprehensive evaluation indicators for the development potential of NIC. Afterward, we used the entropy-weight TOPSIS model to determine the development potential of NIC and analyze its spatio-temporal evolution characteristics. Furthermore, the GeoDetector model was applied to explore the driving mechanism of the NIC development potential. The conclusions were as follows: (1) The Chinese NIC development potential is generally low. The eastern China was the region with the highest development potential year by year, while the development potential in the central China was found to be in an accelerating phase. (2) The evolution of the Chinese NIC development potential’s spatial pattern has been characterized by an inland extension and coastal agglomeration. Moreover, we identified a superior development zone, a rising development zone, an inferior development zone, and a declining development zone. (3) The scope of Chinese NIC development potential agglomeration areas has gradually expanded and its degree has gradually deepened. The range of high-value agglomeration in eastern area gradually expanded and its degree gradually deepened. (4) Investment in innovative talents appears as the core factor affecting the Chinese NIC development potential. Whether acting alone or synergistically with other factors, its promoting effect on Chinese NIC development potential is the strongest.
文摘To investigate the relationship between the ATP content in human oocytes and the deve-lopmental potential of human oocytes, unfertilized oocytes from clinical IVF and immature oocytes unsuitable for ICSI were collected. The ATP content of these unfertilized and in vitro matured eggs were determined quantitatively by measuring the luminescence using an ATP-dependent bioluminescence assay. The result showed that the ATP content of unfertilized oocytes was higher than in vitro matured ones (2.20±0.67 pmol vs 1.72±0.49 pmol, P<0.05 ). In unfertilized oocytes, the ATP content of those whose fertilization rates (FR) was higher than 50 % was 2.43±0.60 pmol, which was significantly different from those whose FR was less than 50 % (1.72±0.56 pmol), while in in vitro matured oocytes, the ATP content of those whose FR more than 50 % was 1.8±0.44 pmol, slightly higher than those less than 50 % (1.55±0.40 pmol), without statistical significance. There was a tendency that the ATP content of oocytes of pregnant patients was higher than those of controls, but the sample number was too small to show any significance in statistics. Briefly, there was positive correlation between the ATP content in oocytes and developmental potential of oocytes.
文摘Microorganisms, regardless of whether pathogenic or not, may cause enormous economic losses due to adverse effects on human and animal health, or by damaging the quality of the agricultural and food products. Based on these effects, the development of prompt molecular methods and their involvement in the practical pathogen diagnostic diagnostics is more than actual. This paper is focused on the evaluation of easy-to-perform and highly budget-friendly, PCR-related DNA purification protocols for diagnostic purposes especially in water or similar simple matrices. The slight modifications of earlier described DNA isolation methods, which rely on chelate exchange resin and/or ethanol-sodium-based heat lysis, we reevaluated in comparison with a widely used commercial kit. The efficiency of DNA purification techniques was assessed from Gramnegative as well as Gram-positive bacteria and yeast using quantitative PCR. The effectivity of different methods tested may vary depending on the bacterial or yeast species in question. Nevertheless, in our hands, the chelate exchange resin-based methods were found to be the most robust and/or satisfying at least by an acceptable reproducibility rate. Our presented results support the potential of low-cost but still sensitive molecular microbe detection procedures consisting of only a few pipetting steps resulting in good reproducibility and the least possible environmental burden, serving as a good starting point for developments of matrix-specific processes and methods.
基金The Sino-Belgian co-operation project on Northwest China funded by the Federal Office for the Scientific, Technical and Cultural Affairs (OSTC) of the Belgium Government, No.BL/10/C15
文摘With the objectives to acquire the fundamental dat a of the territorial resource, understand the impacts of human activit ies on the land use and cover patterns and evaluate the potential of the future exploitation, an intensive land cover classification with an accuracy of 93% has been completed for North Ningxia by remote sen sing technique based on the adoption of a combination method composed o f texture training, maximum likelihood classification and post-processing such as re-allocation and aggregation. This classification result was incorporated with the contemporaneous socio-economic and meteorological d ata for cross-sectional regression modelling to reveal the spatial dete rminants of the land cover patterns and understand the human-environmen tal relationships. A tentative evaluation on the potential of soil exp loitation in the near future was carried out in combination with our land use and cover change detection results aiming at supplying some useful references for the central and local governments in their sustainable l and use planning.
文摘The containerized traffic has come into being for over forty years and has become the most important mode of sea transportation. Although containerized traffic trade has been developed in port cities of Dalian, Yingkou, Dandong and Jinzhou in Liaoning Province, yet their development sped are obviously slower than the entire national development pace. In the article, the authors make a systematic study on the current situation and the potential developmental possibility of containerized traffic in Liaoning Province. It is held that the relative low proportion of the supply of goods in hinterland is relative low which will restrict directly the development potentiality of the container harbors in Liaoning. Three countermeasures of the containerized traffic development were given accordingly.
文摘This paper describes the significance of irrigation on economy development and the status of irrigation development in Tanzania, analyzing the potential and advantages of irrigation development in this country, combined with the major initiatives and experiences which can learn from in the recent 30 years of rural water conservancy in China. Then it discusses the next investment focus on irrigation development for Tanzanian.
文摘Rural revitalization strategy is an important strategic layout of rural development in the new era of the CPC Central Committee,and scientific and reasonable determination of village types is an important measure to promote rural revitalization by classification.The villages of Wan’an County were selected as the research object.Firstly,the factors that have a key impact on the development of the villages were extracted and qualitatively analyzed to preliminarily screen and judge their types.Secondly,the evaluation index system of development potential of the villages was constructed to quantitatively evaluate and reasonably classify the villages.Finally,the spatial distribution characteristics and quantity of different villages were revealed,and differentiated development strategies were proposed.
基金Supported by the Key Project of Science and Technology of Guangxi(1222014-2C)Achievements Transformation Project of Guangxi Academy of Agricultural Science and Technology(201405)Fundamental Research Funds for Guangxi Academy of Agricultural Science and Technology(2014YZ07)~~
文摘Yuan Longping proposed that smash-ridging technology could be extend-ed widely nationwide. ln the research, smash-ridging technology reconstruct cultiva-tion layers with loose soils in agricultural fields, creating "4453" effects, as fol ows: "Four increases" include to increase loosen soil quantity in cultivation layers, soil nutri-ents use, "water pool" in soils, and "oxygen pool" in soils. Four reductions are to reduce soil erosion, carbon emission, salt content and heavy metal in soils. Five resistances refer to improve crop resistance capacity in terms of drought, high tem-perature, lower temperature, disease and lodging. Three improvements indicate to enhance photosynthetic efficiency over 10%, yield in 10%-30% and quality over 5%. lt is researched that without additional chemical fertilizer, yield could increase by 10% by labor force, animal, tractor or smash-ridging machine. What’s more, by smash-ridging cultivation, the depth can be 20 times or higher compared with tractor cultivation, with looser soils. lt is estimated that if smash-ridging cultivation is applied once in agricultural lands in China, present soil layers can be twice as deep as present. Specifical y, the thickness of loose soil-layers could be extended from 10-18 cm at present to 25-35 cm, and natural rainfal would increase by 40 bil ion cm3. After vitalization of soil nutrients, chemical fertilizer would decrease by 7 bil ion kg, and the increased c rops would feed more than 300 mil ion population as per yield at 7 50 kg/hm2.
基金Supported by Coarse Cereal Innovation Team of Shandong Province Modern Agricultural Technology SystemYouth Foundation of Shandong Academy of Agricultural Sciences(2014QNM09)~~
文摘The research reviewed biological characters and nutritional value of Chenopodium quinoa and concluded status quo of domestic cultivation and problems at promotion, as wel as application prospect in order to provide references for re-search and development of Chenopodium quinoa.
基金Project of Hunan Provincial Social Science Achievement Evaluation Committee,No.XSP2023GLC023Excellent Youth Program of the Education Department of Hunan Province,No.22B0692+2 种基金National Natural Science Fundation of China,No.41971191,No.42171213Project of Hunan University of Arts and Science,No.22BSQD15Project of Henan Philosophy and Social Sciences,No.2022BJJ026。
文摘Traditional music is an important component of cultural heritage.However,studies have scarcely explored the tourism development potential and the obstacle factors of traditional music.This study takes Xiangxi as the research site,constructs an evaluation index system,and utilizes survey and geographical methods.The major research results are as follows:First,the average potential of resource endowment,tourism industry development,and socio-economic conditions are 0.28,0.36,and 0.24,respectively.The potential of resource endowment is higher in the west and lower in the east,that of tourism industry development is higher in the north and south and lower in the center,and that of socio-economic conditions is higher in the south and lower in the north.Second,the comprehensive potential is 0.29,which is higher in the northwest and southwest regions.Coordination in most administrative units is at a medium level,and most regions have obvious advantages in resource endowment.Third,the primary obstacle factor is socio-economic conditions(39.21%),followed by resource endowment(30.73%)and tourism industry development(30.06%).The administrative units can be classified into four groups:socio-economic condition obstacle,resource endowment and tourism industry development obstacles,resource endowment and socio-economic condition obstacles,and tourism industry development and socio-economic condition obstacles.The highest priority goals for Xiangxi involve economic development and the integration of modern technologies to stimulate passenger flow.For reg traditional music items(eastern area of Xiangxi),tourism development should be restrained and other resources with stronger inherent advantages should be exploited.This study explored the quantification of traditional music tourism potential,representing a novel breakthrough in this field of research.The indicator system and research methods used in this study can provide guidance and methodological references for cultural heritage research.The suggestions proposed in this article contribute to the rational development and effective protection of cultural heritage resources and the healthy development of the tourism industry.
基金This work was supported by the National Key R&D Program of China(2020YFA0112500 and 2021YFA1100300)the National Natural Science Foundation of China(31721003,31820103009,92168205,32070857 and 31871446)+3 种基金the Young Elite Scientist Sponsorship Program by CAST(2018QNRC001)the key project of the Science and Technology of Shanghai Municipality(19JC1415300)the Shanghai Rising-Star Program(19QA1409600)the Shanghai municipal medical and health discipline construction projects(no.2017ZZ02015).
文摘Chemically defined medium is widely used for culturing mouse embryonic stem cells(mESCs),in which N2B27 works as a substitution for serum,and GSK3βand MEK inhibitors(2i)help to promote ground-state pluripo-tency.However,recent studies suggested that MEKi might cause irreversible defects that compromise the developmental potential of mESCs.Here,we demon-strated the deficient bone morphogenetic protein(BMP)signal in the chemically defined condition is one of the main causes for the impaired pluripotency.Mechanisti-cally,activating the BMP signal pathway by BMP4 could safeguard the chromosomal integrity and proliferation capacity of mESCs through regulating downstream tar-gets Ube2s and Chmp4b.More importantly,BMP4 pro-motes a distinct in vivo developmental potential and a long-term pluripotency preservation.Besides,the pluripotent improvements driven by BMP4 are superior to those by attenuating MEK suppression.Taken together,our study shows appropriate activation of BMP signal is essential for regulating functional pluripotency and reveals that BMP4 should be applied in the serum-free culture system.
基金This work was supported by the "973" Project (Grant No. G1999054205).
文摘In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of target genes. It has long been known that this process is irreversible and the terminal differentiated adult cells, such as cardiac myocytes and neurons, will not divide and differentiate. But recent reports on the two hottest fields - cloning medicine and stem cell biology doubted these concepts. This may lead to a further understanding of the potentiality of mammal development and may provide great chances for commercial and clinical practice.
基金This work was funded by National Science and Technology Major Project of China(Grant No.2011ZX05043)Major Science and Technology Special Project of China National Petroleum Corporation(Grant No:2013E-0502)。
文摘Through analysis of the connotation of unconventional hydrocarbons,the source-reservoir assemblages of unconventional hydrocarbons are divided into three types,i.e.,source-reservoir neighboring type,source-reservoir integration type,and source-reservoir separation type.The source-reservoir neighboring type resources mainly include tight oil and tight gas with the following formation conditions and characteristics:(1)efficient near-source accumulation close to high-quality source rocks with the pressure difference between source and reservoir as the dynamic force;(2)large-area tight reservoirs with certain porosity,dominated by micro-nanopores of inorganic origin;(3)distributed in depressions and slopes with large hydrocarbon-bearing area and great resource quantity,low abundance and local development of“sweet spots”;(4)weak tectonism.The source-reservoir integration type resources mainly include coalbed methane,shale gas,shale oil and oil shale.The formation conditions and characteristics are:(1)high abundance of organic matter,different types of organic matter and thermal evolution grades leading to formation of different resources types;(2)organic-rich sections are distributed continuously in the reservoiring space which is dominated by nanometer organic pores,interparticle pores and microfissures;(3)hydrocarbons mainly occur in free or adsorbed state,varying much with resource type;(4)the resources are self-conserved,and enriched in depressions and slopes,the conservation conditions are controlled by tectonics,temperature and pressure;(5)the production per well can be enhanced by volume fracturing,which increases the permeability of the reservoirs.The source-reservoir separation type resources are more special,mainly including(1)transformed conventional resources such as oil sand and heavy oil;(2)unsteady resources formed under special conditions of temperature and pressure,among which natural gas hydrate is a representative.These three types of resources in China are different in both development prospect and current situation:(1)the source-reservoir neighboring type is most practical and will develop fast in the next 5 years;(2)the source-reservoir integration type needs continuous exploration and technical breakthrough,and is expected to develop rapidly in the coming decade;(3)in the source-reservoir separation type resources,natural gas hydrates have the greatest development potential,on which technical tests are being conducted.