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Geoscience Frontiers 2024 Annual Convention
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作者 Lily Wang Mudan Yin Yongqiang Yang 《Geoscience Frontiers》 2025年第3期439-442,共4页
The 2024 Geoscience Frontiers Annual Convention was held in Kuching,Malaysia,from November 18th to 22th,2024,jointly with the 2024 IAGR Annual Convention and the 21st International Conference on Gondwana to Asia.The I... The 2024 Geoscience Frontiers Annual Convention was held in Kuching,Malaysia,from November 18th to 22th,2024,jointly with the 2024 IAGR Annual Convention and the 21st International Conference on Gondwana to Asia.The IAGR Convention attracted over 150 participants from various countries,including China,India,Australia,the Republic of Korea,Japan,Malaysia,Indonesia,Thailand,Italy,Mexico,the United Kingdom,Saudi Arabia,France,and Brunei. 展开更多
关键词 Kuching International Conference Gondwana Asia Malaysia Geoscience Frontiers Annual convention geoscience frontiers annual convention IAGR Annual convention COUNTRIES China
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The 22nd China Kizang Mountaineering Convention Kicked off in Lhasa
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《China's Tibet》 2025年第3期F0002-F0002,共1页
On April 30,the 22nd China Xiza ng Mountai neering Conventi on in 2025 comme need.As its flagship eve nt,the Luodui Peak Mountaineering Expedition took place from May 2 to 3 in Yangbajain Town of Lhasa,attracting more... On April 30,the 22nd China Xiza ng Mountai neering Conventi on in 2025 comme need.As its flagship eve nt,the Luodui Peak Mountaineering Expedition took place from May 2 to 3 in Yangbajain Town of Lhasa,attracting more than 160 mountain climbing enthusiasts from all over the country. 展开更多
关键词 Kizang Mountaineering convention Xiza Mountaineering convention Luodui Peak Mountaineering Expedition mountain climbing enthusiasts China luodui peak mountaineering expedition LHASA Yangbajain Town
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A Comparative Study on South Korea’s Response to the UN Climate Change Convention and the Biodiversity Convention
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作者 JinYoung Son HyeMin Park 《Research in Ecology》 2025年第1期46-61,共16页
Climate change and biodiversity loss are intricately linked,and as the severity of these challenges intensifies,the need for a cohesive international response has become increasingly evident.Since 1992,South Korea has... Climate change and biodiversity loss are intricately linked,and as the severity of these challenges intensifies,the need for a cohesive international response has become increasingly evident.Since 1992,South Korea has developed relevant legal and institutional frameworks;however,its initiatives addressing biodiversity loss have received less recognition and prioritization compared to its efforts concerning climate change.In this context,this study aims to analyze the disparities in South Korea’s policy responses to the United Nations Framework Convention on Climate Change(UNFCCC)and the Convention on Biological Diversity(CBD),while proposing an integrated policy direction.To achieve this,the study compares key policies related to both conventions by utilizing the OECD’s Policy Coherence for Sustainable Development(PCSD)indicators and evaluation criteria derived from previous research.Furthermore,the analysis incorporates variables identified in earlier studies,including legal enforceability,economic incentives,financial support,and industry participation,to enhance the depth of the analysis.Additionally,a review of international best practices was conducted to extract actionable insights for policy enhancement.The analysis reveals several challenges in biodiversity policies,including fragmented governance systems,low policy prioritization,weakened policy momentum,imbalanced financial support,and limited corporate awareness.Moreover,difficulties in quantitative evaluation hinder the verification of policy effectiveness due to the complex nature of biodiversity goals.This research aims to assess South Korea’s responsiveness in accordance with the integrated approach promoted by the international community. 展开更多
关键词 United Nations Framework convention on Climate Change(UNFCCC) convention on Biological Diversity(CBD) Policy Comparison
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Advancements in conventional cancer therapy combined with immunotherapy 被引量:3
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作者 Hongxia Li Songyan Han +1 位作者 Chunbo Dong Zhida Liu 《Oncology and Translational Medicine》 2025年第1期17-28,共12页
Conventional therapies are primary cancer treatments that directly eliminate or inhibit the growth of tumor cells,reducing the overall tumor burden.Increasing evidence suggests that conventional therapies possess sign... Conventional therapies are primary cancer treatments that directly eliminate or inhibit the growth of tumor cells,reducing the overall tumor burden.Increasing evidence suggests that conventional therapies possess significant immunomodulatory properties in addition to their established direct tumoricidal effects.Emerging immunotherapies have revolutionized the clinical management of various cancer types.Conventional therapy and immunotherapy have demonstrated remarkable clinical efficacy,leading to numerous ongoing clinical investiga-tions exploring their potential synergistic effects.However,trials investigating the combination of conventional therapy and immunotherapy have shown limited synergistic therapeutic efficacy.This unsatisfactory clinical outcome may be attributed to the suboptimal design of the combination approach and the inadequate understanding of the mechanisms and impacts of radiotherapy,chemotherapy,targeted ther-apy regimens(including dosing,timing,and administration route),and surgery on both cancer cells and the host immune system.Here,we comprehensively review preclinical and clinical investigations exploring the therapeutic effects and mechanisms of conventional therapy alone or in combination with immunotherapy.We proposed that optimizing the dosing,timing,and route of administration of conventional therapies can enhance the synergistic efficacy of combination therapies,thus offering significant clinical advantages. 展开更多
关键词 conventional therapy Tumor microenvironment IMMUNOTHERAPY Combinational therapy
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Sono-urethrogram versus conventional urethrogram in the assessment of urethral stricture disease:A prospective comparative study
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作者 Akash Chitrakar Baikuntha Adhikari +4 位作者 Udita Mishra Arvind Kumar Shah Robin Bahadur Basnet Parash Mani Shrestha Anil Shrestha 《Asian Journal of Urology》 2025年第2期262-266,共5页
Objective:The management of urethral stricture disease depends on the location,length of stricture,and associated urethral pathology.These parameters are obtained from preoperative imaging,with conventional urethrogra... Objective:The management of urethral stricture disease depends on the location,length of stricture,and associated urethral pathology.These parameters are obtained from preoperative imaging,with conventional urethrogram(retrograde urethrogram and micturating cystourethrogram[RGU/MCU])being the diagnostic tool of choice despite its many shortcomings.Sono-urethrogram(SUG)is an alternative that addresses most issues of RGU/MCU.Studies comparing RGU/MCU with SUG are limited.With the objective of comparing these two imaging modalities in the evaluation of urethral stricture disease,a prospective study was conducted.Methods:Fifty-six patients suspected of urethral stricture disease on clinical evaluation and confirmed either on RGU/MCU or urethro-cystoscopy were included in the study.SUG was performed by the experienced consultant radiologist who was blinded to the report of RGU/MCU.Findings of RGU/MCU and SUG were compared to intraoperative findings,which served as the reference standard.Results:The median length of the stricture determined intraoperatively was 16.5 mm,by RGU/MCU was 5.8 mm,and by SUG was 13.5 mm.The diagnostic accuracy for determination of the stricture location was 93%for RGU/MCU and 98%for SUG.SUG identified spongiofibrosis in 90%of patients with higher accuracy for the severe degree of spongiofibrosis.Conclusion:SUG has been shown to be more accurate than RGU/MCU in estimating stricture length(both short and intermediate)and localizing the stricture location.Use of SUG in conjunction with RGU/MCU helps in better guidance of stricture management by improving preoperative assessment.Further studies with larger sample sizes are warranted. 展开更多
关键词 conventional urethrogram Retrograde urethrogram Sono-urethrogram Spongiofibrosis Urethral stricture
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The cultures of science quadrant:Scientific representations,practices and conventions in the East and West
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作者 Luke J Buhagiar Stavroula Tsirogianni Gordon Sammut 《Cultures of Science》 2025年第2期140-155,共16页
This paper considers the notions of common sense and interobjectivity to articulate an understanding of how different cultural realities give rise to different construals of scientific phenomena across distinct cultur... This paper considers the notions of common sense and interobjectivity to articulate an understanding of how different cultural realities give rise to different construals of scientific phenomena across distinct cultures. Our main focus in this paper is on the social sciences. We propose a quadrant of different cultural–scientific stances from which the study of social phenomena is possible, based on the emic–etic dimension pertaining to the study of culture from contrasting perspectives. Although the emic–etic distinction is normal y applied in fields within the science of culture, it is proposed here that the distinction is in some ways germane to scientific practice in general, making it amenable for use in a culture of science(CoS) programme. The four perspectives that emerge from the quadrant are illustrated using exemplars. Different aspects of CoS—that is, scientific practice, scientific conventions and representations of science—are then discussed in further detail, including in two tables illustrating points of convergence and divergence between the East and West when it comes to different aspects of CoS. 展开更多
关键词 Science culture EMIC etic interobjectivity common sense culture of science REPRESENTATIONS conventIONS scientific practice
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Pathogen Detection in Spinal Infections:Next-Generation Sequencing Versus Conventional Microbiological Methods
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作者 Khan Akhtar Ali Ling-xiao He +4 位作者 Fang Gao Ze-an Xia Hui Huang Heng Zeng Wei-hua Hu 《Current Medical Science》 2025年第2期331-340,共10页
Objective and Background Early and accurate diagnosis of spinal infections,including spinal tuberculosis,is pivotal for effective treatment but remains challenging.This study aims to assess the diagnostic yield of met... Objective and Background Early and accurate diagnosis of spinal infections,including spinal tuberculosis,is pivotal for effective treatment but remains challenging.This study aims to assess the diagnostic yield of metagenomic next-generation sequencing(mNGS)compared with that of conventional microbiological tests(CMTs)in identifying pathogens associated with spinal pathologies,with a special focus on infections leading to surgical interventions.Methods We enrolled 85 patients who underwent spinal surgery,comprising 63 patients with clinically diagnosed spinal infections,including patients with spinal tuberculosis,and 22 patients with noninfectious spinal conditions.The procedures involved irrigation and debridement for persistent wound drainage,with subsequent DNA extraction from plasma and joint fluid for mNGS and CMT analysis.Results Significantly increased C-reactive protein(CRP)levels were observed in patients with infections.The mNGS approach showed greater diagnostic sensitivity(92.06%)for detecting pathogens,including Mycobacterium tuberculosis,than did CMTs(36.51%).Despite its low specificity,mNGS had considerable negative predictive value(70.59%),underscoring its utility in ruling out infections.Conclusions The mNGS offers superior sensitivity over CMTs in the diagnosis of a variety of spinal infections,notably spinal tuberculosis.This study highlights the potential of mNGS in enhancing the diagnosis of complex spinal infections,thereby informing targeted treatment strategies. 展开更多
关键词 Metagenomic next-generation sequencing conventional microbiological tests Spinal infections-Sensitivity SPECIFICITY Predictive value D-DIMERS
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Pore pressure prediction based on conventional well logs and seismic data using an advanced machine learning approach
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作者 Muhsan Ehsan Umar Manzoor +6 位作者 Rujun Chen Muyyassar Hussain Kamal Abdelrahman Ahmed E.Radwan Jar Ullah Muhammad Khizer Iftikhar Farooq Arshad 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2727-2740,共14页
Pore pressure is a decisive measure to assess the reservoir’s geomechanical properties,ensures safe and efficient drilling operations,and optimizes reservoir characterization and production.The conventional approache... Pore pressure is a decisive measure to assess the reservoir’s geomechanical properties,ensures safe and efficient drilling operations,and optimizes reservoir characterization and production.The conventional approaches sometimes fail to comprehend complex and persistent relationships between pore pressure and formation properties in the heterogeneous reservoirs.This study presents a novel machine learning optimized pore pressure prediction method with a limited dataset,particularly in complex formations.The method addresses the conventional approach's limitations by leveraging its capability to learn complex data relationships.It integrates the best Gradient Boosting Regressor(GBR)algorithm to model pore pressure at wells and later utilizes ContinuousWavelet Transformation(CWT)of the seismic dataset for spatial analysis,and finally employs Deep Neural Network for robust and precise pore pressure modeling for the whole volume.In the second stage,for the spatial variations of pore pressure in the thin Khadro Formation sand reservoir across the entire subsurface area,a three-dimensional pore pressure prediction is conducted using CWT.The relationship between the CWT and geomechanical properties is then established through supervised machine learning models on well locations to predict the uncertainties in pore pressure.Among all intelligent regression techniques developed using petrophysical and elastic properties for pore pressure prediction,the GBR has provided exceptional results that have been validated by evaluation metrics based on the R^(2) score i.e.,0.91 between the calibrated and predicted pore pressure.Via the deep neural network,the relationship between CWT resultant traces and predicted pore pressure is established to analyze the spatial variation. 展开更多
关键词 Pore pressure conventional well logs Seismic data Machine learning Complex formations
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Advancing hemostasis:A meta-analysis of novel vs conventional endoscopic therapies for non variceal upper gastrointestinal bleeding
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作者 Shivangini Duggal Ishana Kalra +1 位作者 Keisha Kalra Vicky Bhagat 《World Journal of Gastrointestinal Endoscopy》 2025年第6期107-119,共13页
BACKGROUND Non variceal upper gastrointestinal bleeding(NVUGIB)is a life-threatening condition requiring prompt and effective hemostasis.Various endoscopic inter-ventions,including novel hemostatic powders(HP),over-th... BACKGROUND Non variceal upper gastrointestinal bleeding(NVUGIB)is a life-threatening condition requiring prompt and effective hemostasis.Various endoscopic inter-ventions,including novel hemostatic powders(HP),over-the-scope clips(OTSC),and traditional approaches,have been employed to manage upper gastroin-testinal bleeding(UGIB).Despite advancements,comparative efficacy and safety of these modalities remain uncertain.AIM To evaluate the efficacy and safety of novel hemostatic interventions compared to conventional endoscopic techniques for managing UGIB.METHODS Cochrane,MEDLINE,PubMed and Scopus libraries were searched for rando-mized controlled trials(RCTs)published up to October 2024.Only RCTs compa-ring novel interventions,such as HP or OTSC,with conventional endoscopic treatments computed tomography(CT)were included.The primary outcome was the 30-day rebleeding rate.Secondary outcomes included initial hemostasis,short-term rebleeding rates,need for salvage therapy(surgical/angiographic),30-day all-cause mortality,and bleeding-related mortality.We performed pairwise and network meta-analyses for all treatments.RESULTS Seventeen studies were included in this analysis.Regarding the 30-day rebleeding rate,OTSC and HP showed superior efficacy compared with CT[OTSC vs CT:Relative risk(RR):0.47,95%confidence interval(CI):0.33-0.65;HP vs CT:RR:0.73,95%CI:0.45-1.13],while OTSC and HP had comparable efficacy(RR:0.56,95%CI:0.30-1.05).OTSC ranked the highest in the network ranking estimate for this outcome.For the secondary outcomes,OTSC demonstrated superior efficacy for the short-term rebleeding rate(OTSC vs CT:RR:0.35,95%CI:0.14-0.74;HP vs CT:RR:0.62,95%CI:0.28-1.35;OTSC vs HP:RR:0.59,95%CI:0.17-1.67).Regarding the initial hemostasis rate,OTSC was slightly more effective than CT(OTSC vs CT:RR:1.20,95%CI:1.06-1.57)and comparable to HP(OTSC vs HP:RR:1.08,95%CI:0.89-1.40).There were no significant differences among treatments for all-cause mortality,bleeding-related mortality,or the necessity of surgical or angiographic salvage therapy.OTSC consistently ranked highest across most outcomes in the network ranking estimate. 展开更多
关键词 Hemostatic methods Non-variceal upper gastrointestinal bleeding Over-the-scope-clips conventional methods Hemostatic spray
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Comparative evaluation of diaphragmatic excursion in ICU patients:ultrasonography assessment via the conventional M-mode versus the anatomical M-mode
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作者 Issac Cheong Francisco Marcelo Tamagnone 《World Journal of Emergency Medicine》 2025年第5期488-490,共3页
Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventiona... Diaphragmatic function is central to respiration,and its evaluation is critical in intensive care unit(ICU)settings.Ultrasonography is a reliable bedside tool to assess diaphragmatic excursion(DE).[1,2]The conventional M-mode(MM)offers high-resolution imaging but requires precise alignment,which can be diffi cult in ICU patients.[3-5]Anatomical M-mode(AMM)allows flexible line adjustment,enabling accurate DE measurements despite poor acoustic windows.[6]However,comparative data between MM and AMM are limited.This retrospective study evaluated the concordance between MM and AMM for assessing right DE. 展开更多
关键词 intensive care unit conventional M mode anatomical M mode diaphragmatic excursion ULTRASONOGRAPHY precise alignmentwhich
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Orderly distribution and differential enrichment of conventional and unconventional hydrocarbons in the Cretaceous Qingshankou Formation,northern Songliao Basin,NE China
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作者 BAI Xuefeng LI Junhui +1 位作者 ZHENG Qiang CHEN Fangju 《Petroleum Exploration and Development》 2025年第5期1140-1149,共10页
Based on the petroleum exploration in the Cretaceous Qingshankou Formation,northern Songliao Basin,NE China,integrated with seismic,drilling and logging data,this study investigates the characteristics and genetic mec... Based on the petroleum exploration in the Cretaceous Qingshankou Formation,northern Songliao Basin,NE China,integrated with seismic,drilling and logging data,this study investigates the characteristics and genetic mechanisms of orderly distribution and the differential enrichment patterns of conventional and unconventional hydrocarbons in the formation.Key findings involve five aspects.First,the conventional and unconventional hydrocarbons coexist orderly.Laterally,conventional oil,tight oil,and shale oil form a pattern of orderly accumulation from basin margins to the center.Vertically,shale oil,tight oil,and conventional oil develop progressively upward.Second,the coupled tectonic-sedimentary processes govern sedimentary facies differentiation and diagenesis,influencing reservoir physical properties and lithology,thereby controlling the orderly distribution of conventional and unconventional hydrocarbons in space.Third,the coupling of source rock hydrocarbon generation evolution,fault sealing capacity,and reservoir densification determines the orderly coexistence pattern of conventional and unconventional hydrocarbons.Fourth,sequential variations in reservoir physical properties generate distinct dynamic fields that regulate hydrocarbon orderly accumulation.Fifth,enrichment controls are different depending on hydrocarbon types:buoyancy-driven,fault-transport,sandbody-connected,and trap-concentrated,for above-source conventional oil;overpressure-driven,fault-transport,multi-stacked sandbodies,and quasi-continuous distribution for near-source tight oil and gas;self-sourced reservoirs,retention through self-sealing,in-situ accumulation or micro-migration driven by hydrocarbon-generation overpressure for inner-source shale oil.From exploration practices,these findings will effectively guide the integrated deployment and three-dimensional exploration of conventional and unconventional hydrocarbon resources in the Qingshankou Formation,northern Songliao Basin. 展开更多
关键词 Songliao Basin Cretaceous Qingshankou Formation conventional oil reservoir tight oil shale oil orderly distribution differential enrichment
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Underwater vs conventional endoscopic mucosal resection for nonpedunculated colorectal neoplasms:A randomized controlled trial
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作者 Quang D Le Nhan Q Le Duc T Quach 《World Journal of Gastrointestinal Surgery》 2025年第6期325-334,共10页
BACKGROUND Underwater endoscopic mucosal resection(UEMR)has been shown to be a good treatment option for the management of nonpedunculated polyps≥10 mm since its introduction.However,there is a paucity of randomized ... BACKGROUND Underwater endoscopic mucosal resection(UEMR)has been shown to be a good treatment option for the management of nonpedunculated polyps≥10 mm since its introduction.However,there is a paucity of randomized controlled trials(RCTs)in Asia.AIM To compare the efficacy and safety of UEMR with those of conventional EMR(CEMR)in treating nonpedunculated colorectal lesions.METHODS We carried out this RCT at a tertiary hospital from October 2022 to July 2024.Patients with nonpedunculated colorectal neoplasms ranging from 10 mm to 30 mm in size were randomly assigned to either the UEMR or CEMR group.The primary outcome was the curative resection(R0)rate.The secondary outcomes included en bloc resection,procedure time,adverse events,and the number of clips used for defect closure.RESULTS A total of 260 patients with 260 lesions(130 in each UEMR and CEMR group)were recruited.The median age was 58(27-85)years,the male/female ratio was 1.74,and the median lesion size was 20(10-30 mm)mm.Compared with CEMR,UEMR was associated with a significantly greater curative resection(R0)rate(98.4%vs 90.3%;P=0.007),greater en bloc resection rate(100%vs 94.6%;P=0.014),shorter procedure time(65 vs 185 seconds;P<0.001),lower rate of bleeding complications(1.5%vs 10%;P=0.003),and fewer clips used(2 vs 3;P<0.001).No perforations were observed in either group.CONCLUSION Compared with CEMR,UEMR has a higher R0 rate,greater en bloc resection rate,shorter procedure time,fewer bleeding complications,and clips used in the management of nonpedunculated colorectal neoplasms. 展开更多
关键词 Nonpedunculated colorectal neoplasms Underwater endoscopic mucosal resection conventional endoscopic mucosal resection En bloc resection Curative resection
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Introduction on Several Conventions of Contemporary Accounting
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作者 Gaoli Shengli Sunqiong Xie zhenkai 《International English Education Research》 2014年第6期4-5,共2页
Accounting conventions are concepts and rules which have been generally accepted in performing accounting. It came from a careful observation of accounting practice, the accounting practice revealed patterns of consis... Accounting conventions are concepts and rules which have been generally accepted in performing accounting. It came from a careful observation of accounting practice, the accounting practice revealed patterns of consistent behavior. 展开更多
关键词 the entity convention going convention money convention CONSERVATISM OBJECTIVITY
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Difference of Nitrogen Uptake and Use Efficiency in Conventional Indica Rice Cultivars with Different Nitrogen Use Efficiency for Grain Output 被引量:3
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作者 周娟 李进前 +4 位作者 张彪 张传胜 张岳芳 王余龙 董桂春 《Agricultural Science & Technology》 CAS 2008年第6期68-73,141,共7页
[Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice... [Objective] The study aimed to confirm difference of nitrogen uptake and used efficiency with different nitrogen use efficiency for grain output (NUEg) types of indica rice.[Method] 88 and 122 conventional indica rice cultivars were solution-cultured in 2001 and 2002, respectively. Dry matter weight (including root system, culm and sheath, leaves, panicle), nitrogen content of different organs, yield and its components were measured. The tested rice cultivars were classified into 6 types (i.e. A, B, C, D, E and F, A was the lowest, and F was the highest) based on their NUEg level by the MinSSw method.[Result](1)Difference of NUEg of the cultivars used in this study were very large; (2) No significant difference of N content at heading stage was observed among different NUEg types of indica rice. In the cultivars with higher NUEg, however, N content in leaf, stem-sheath and entire rice plant were lower at mature stage. (3)Cultivars with higher NUEg were characterized with lower N uptake before heading and at mature stage; (4) Cultivars with higher NUEg were characterized with higher N use efficiency in biomass production and harvest index. [Conclusion] The cultivars with higher NUEg showed lower N uptake and N content, while nitrogen use efficiency was higher. 展开更多
关键词 conventional INDICA rice CULTIVARS NITROGEN content for grain output NITROGEN UPTAKE NITROGEN use efficiency
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Buoyance-driven hydrocarbon accumulation depth and its implication for unconventional resource prediction 被引量:39
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作者 Xiongqi Pang Chengzao Jia +6 位作者 Wenyang Wang Zhangxin Chen Maowen Li Fujie Jiang Tao Hu Ke Wang Yingxun Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第4期93-109,共17页
The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconve... The discovery of unconventional hydrocarbon resources since the late 20th century changed geologists’understanding of hydrocarbon migration and accumulations and provides a solution to energy shortage.In 2016,unconventional oil production in the USA accounted for 41%of the total oil production;and unconventional natural gas production in China accounted for 35%of total gas production,showing strong growth momentum of unconventional hydrocarbons explorations.Unconventional hydrocarbons generally coexist with conventional petroleum resources;they sometimes distribute in a separate system,not coexisting with a conventional system.Identification and prediction of unconventional resources and their potentials are prominent challenges for geologists.This study analyzed the results of 12,237 drilling wells in six representative petroliferous basins in China and studied the correlations and differences between conventional and unconventional hydrocarbons by comparing their geological features.Migration and accumulation of conventional hydrocarbon are caused dominantly by buoyance.Wepropose a concept of buoyance-driven hydrocarbon accumulation depth to describe the deepest hydrocarbon accumulation depth driven dominantly by buoyance;beyond this depth the buoyance becomes unimportant for hydrocarbon accumulation.We found that the buoyance-driven hydrocarbon accumulation depth in petroliferous basins controls the different oil/gas reservoirs distribution and resource potentials.Hydrocarbon migration and accumulations above this depth is dominated by buoyancy,forming conventional reservoirs in traps with high porosity and permeability,while hydrocarbon migration and accumulation below this depth is dominated by non-buoyancy forces(mainly refers to capillary force,hydrocarbon volumeexpansion force,etc.),forming unconventional reservoirs in tight layers.The buoyance-driven hydrocarbon accumulation depths in six basins in China range from 1200mto 4200 m,which become shallowerwith increasing geothermal gradient,decreasing particle size of sandstone reservoir layers,or an uplift in the whole petroliferous basin.The predicted unconventional resource potential belowthe buoyance-driven hydrocarbon accumulation depth in six basins in China is more than 15.71×10^(9) t oil equivalent,among them 4.71×10^(9) t reserves have been proved.Worldwide,94%of 52,926 oil and gas reservoirs in 1186 basins are conventional reservoirs and only 6%of them are unconventional reservoirs.These 94%conventional reservoirs show promising exploration prospects in the deep area below buoyance-driven hydrocarbon accumulation depth. 展开更多
关键词 Nature energy Fossil energy Oil and gas resources conventional hydrocarbon reservoirs Unconventional hydrocarbon reservoirs Buoyance-driven hydrocarbon accumulation DEPTH
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Theory, technology and prospects of conventional and unconventional natural gas 被引量:31
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作者 ZOU Caineng YANG Zhi +8 位作者 HE Dongbo WEI Yunsheng LI Jian JIA Ailin CHEN Jianjun ZHAO Qun LI Yilong LI Jun YANG Shen 《Petroleum Exploration and Development》 2018年第4期604-618,共15页
The development of natural gas in China has entered a golden and leap-forward stage, which is a necessary bridge to clean energy. This in-depth study on the status quo, theory, technology and prospect of natural gas d... The development of natural gas in China has entered a golden and leap-forward stage, which is a necessary bridge to clean energy. This in-depth study on the status quo, theory, technology and prospect of natural gas development shows:(1) The global remaining proven recoverable reserves of natural gas are 186×1012 m3, and the reserves-production ratio is 52.4, indicating a solid resource base for long-term and rapid development.(2) Ten formation and distribution laws of conventional and unconventional natural gas reservoirs have been proposed. In terms of exploration geology, the theory of conventional "monolithic" giant gas fields with different gas sources, and an unconventional gas accumulation theory with continuous distribution of "sweet areas" in different lithologic reservoirs have been established; in terms of development geology, a development theory of conventional structural gas reservoirs is oriented to "controlling water intrusion", while a development theory of unconventional gas is concentrated on man-made gas reservoirs.(3) With the geological resources(excluding hydrates) of 210×1012 m3 and the total proven rate of the resources less than 2% at present, the natural gas in China will see a constant increase in reserve and production; by 2030, the proven geological reserves of natural gas are expected to reach about(6 000-7 000)×108 m3, the production of conventional and unconventional natural gas each will reach about 1 000×108 m3, and the gas consumption will reach 5 500×108 m3. The dependence on imported natural gas may be 64% by 2030, and 70% by 2050.(4) Ten measures for future development of natural gas have been proposed, including strengthening exploration in large-scale resource areas, increasing the development benefits of unconventional gas, and enhancing the peak adjusting capacity of gas storage and scale construction of liquified natural gas. 展开更多
关键词 natural GAS GAS GEOLOGY conventIONAL and UNconventIONAL GAS GEOLOGY shale GAS TIGHT GAS man-made GAS reservoir renewable energy controlling water INTRUSION LNG
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An efficient synthesis of benzofuran derivatives under conventional/non-conventional method 被引量:1
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作者 Suryakant B.Sapkal Kiran F.Shelke +1 位作者 Bapurao B.Shingate Murlidhar S.Shingare 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1439-1442,共4页
l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina(Al2O3) has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave ir... l-Methyl-3-ethyl imidazolium bromide[meim]Br/basic alumina(Al2O3) has been found to promote the cyclocondensation of chloroacetone/chloroethyl acetate with salicylaldehydes under conventional as well as microwave irradiation to yield benzofuran derivatives. 展开更多
关键词 [meim]Br/Al2O3 BENZOFURAN CYCLOCONDENSATION conventIONAL Non-conventional methods
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Analysis of Yield Traits in Conventional Rice Varieties
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作者 张现伟 李经勇 +3 位作者 郑家奎 姚雄 甘兴友 唐永群 《Agricultural Science & Technology》 CAS 2016年第4期852-856,共5页
From the breeding of conventional dwarf rice varieties in the 1960 s to rice heterosis utilization in the 1970 s, the improvement of yield traits has been a primary goal of rice breeding. However, the yield potential ... From the breeding of conventional dwarf rice varieties in the 1960 s to rice heterosis utilization in the 1970 s, the improvement of yield traits has been a primary goal of rice breeding. However, the yield potential of multiple hybrid rice varieties bred successfully in recent twenty years is not significantly higher than that of early bred rice varieties. Due to continuous development and application of new germplasm resources, the yield of conventional rice varieties has been improved constantly. Currently, the yield of some conventional rice varieties is higher than that of hybrid rice. In order to clarify differences between the yield of conventional rice and hybrid rice, and reevaluate conventional rice varieties, in this study, conventional rice and hybrid rice combinations with the same genetic background were compared to analyze the yield and related traits of these 12 combinations. In the comparative experiments of 12 combinations of conventional rice and hybrid rice, the combinations in which yield of hybrid rice was significantly higher than that of conventional rice accounted for 41.7%; the combinations in which yield of conventional rice was higher than that of hybrid rice accounted for 16.6%; the combinations in which no significant differences were found between the yield of conventional rice and hybrid rice accounted for 41.7%. The yield of several conventional rice varieties was equal to or even higher than that of hybrid rice with the same genetic background. This study could provide theoretical reference for the genetic breeding, popularization and application of conventional rice. 展开更多
关键词 conventional rice Hybrid rice YIELD
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Conventional Geothermal Systems and Unconventional Geothermal Developments: An Overview 被引量:1
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作者 Maryam Khodayar Sveinbjörn Björnsson 《Open Journal of Geology》 CAS 2024年第2期196-246,共51页
This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal syste... This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. Medium-temperature (MT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at <7 Km depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. Meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development. 展开更多
关键词 conventional Geothermal Systems Unconventional Geothermal Developments Shallow and Deep Closed-Loops Enhanced Geothermal Systems Supercritical and Millimeter-Wave Drilling
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Epigenetic Effects of Special Plant Nutritional Elements(SPNE) on Four Generations of Conventional Rice
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作者 余素芹 田长恩 +2 位作者 谢国文 常绍明 胡位荣 《Agricultural Science & Technology》 CAS 2014年第11期1888-1893,1898,共7页
[Objective] The epigenetic effects of special plant nutritional elements (SP-NE) on 4 generations of conventional rice were investigated. [Method] The 4 gener-ations of a conventional rice cultivar were al treated w... [Objective] The epigenetic effects of special plant nutritional elements (SP-NE) on 4 generations of conventional rice were investigated. [Method] The 4 gener-ations of a conventional rice cultivar were al treated with the SPNE. The effects of SPNE on the yield of the 4 generations were investigated. From the 1st generation to the 4th generations, some seeds were treated with the SPNE and water alterna-tively, and some seeds were treated with the SPNE persistently. Under these condi-tions, the effects of SPNE on the yield of rice were studied. In addition, the epige-netic effects of spraying times of SPNE on the yield of rice within the same gener-ation were studied. According to the national standard for pol utant content in food (GB 2762-2012), the heavy metal content, particularly the Cd content, and the pro-tein content in rice grains were determined. [Result] The increase and the epigenetic increase of yield of rice treated with SPNE were al enlarged generation by genera-tion. The yield differed among different plots even under the same SPNE treatment. But the yield increase was similar within the same plot. The epigenetic effects of spraying times of SPNE on the yield were also similar. The pol utant content in rice grains was al less than the limited content required by the national standard. The Cd content was lower and the protein content was higher in the rice treated with SPNE compared to that in the rice treated with water, indicating the rice treated with SPNE was more safe and nutritional. [Conclusion] We hope to provide a theo-retical basis for the production of conventional rice. 展开更多
关键词 SPNE conventional rice Epigenetic effects Four generations
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