Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 1...Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution.展开更多
The spike-grain structure and yield data of winter wheat observed at 10 winter wheat observation stations in Jiangsu agrometeorological observation stations in the China Meteorological Observation Network were used to...The spike-grain structure and yield data of winter wheat observed at 10 winter wheat observation stations in Jiangsu agrometeorological observation stations in the China Meteorological Observation Network were used to design the assessment model and evaluation criteria of the effects of climate change on spikegrain structure and yield of winter wheat. The linear regression method was used to determine the parameters of the assessment model,and the climate fact extrapolation method was used to determine future climate change scenarios. The effects of climate change on spike-grain structure and yield of winter wheat in Jiangsu Province were calculated and analyzed finally. The results showed that with the climate change,the meteorological conditions during the growth and development of winter wheat changed,which caused the number of effective spikes to decrease,and the number of grains per spike and thousand-grain weight to increase,and this new type of spike-grain structure combination was beneficial to the increase of the unit yield of winter wheat. The variations of meteorological elements caused by climate change during winter wheat growth and development had different effects on spike-grain structure at different growth stages. The spike-grain structure had an "increasing-decreasing" periodic variation with the growth period overall,with a period of one to three stages. The relationship between winter wheat growth and development and meteorological conditions can be adjusted in real time through stress-resistant cultivation techniques to achieve the high-yield and high-quality cultivation target of winter wheat production.展开更多
In this paper, electromagnetic emissions recorded by a borehole TOA installment with three observing channels of CH1 (0.01 - 0.1 Hz), CH2 (0.1 - 1.0 Hz) and CH3 (1 - 9 kHz) before four large earthquakes with magnitude...In this paper, electromagnetic emissions recorded by a borehole TOA installment with three observing channels of CH1 (0.01 - 0.1 Hz), CH2 (0.1 - 1.0 Hz) and CH3 (1 - 9 kHz) before four large earthquakes with magnitudes more than 8.0 have been depicted. These abnormities present different fluctuating processes from one another. For the Wenchuan MS 8.0 earthquake on 12 May 2008, the nearest one among these four events and only 660 km from the TOA station, electromagnetic information appeared at least 5 months ago in two low frequency bands of CH1 and CH2 and it was subjected to an obvious fluctuating process with several developing stages: initial information, intensive anomaly and large amplitude signals. The typical pulse-like emissions in CH2 happened group by group with large various magnitudes, which can be of 10 mV in the climax period. While during this period, compatible wave-like information with little magnitudes also happened in CH1 channel and a few pulses in CH3. Anomalous emissions occurred about 4 months prior to the 25 April 2015 Nepal MS 8.1 event, 1560 km away from the TOA station. The abnormal information in CH2 also appeared group by group but with small various magnitudes, more than 2 mV during their climax. This process is also effective for the Sumatra MS 8.9 earthquake on 26 December 2004, 2500 km from the borehole TOA, only with a different duration of 2 months and less magnitudes of 0.1 mV in CH1 and 1 mV in CH2 in this case. However, there is no obvious fluctuation and only small constant amplitude signals being ~0.15 mV appeared during 2 weeks before the Japan MS 9.0 earthquake on 11 March 2011. It is the farthest one among these four events and beyond 4000 km from the observing station. So, we can make a conclusion that there is a near relationship between the properties of the abnormities associated with these four earthquakes, such as amplitudes, duration and signal types, and the distances from TOA station: on one hand, the amplitude and duration decreases as the distance increases;on the other hand, there is an evolution for emission properties from complex various magnitude signals to single equal magnitude ones as the distance changes to be far. However, one common feature of the anomalous information related to these four events is that almost electromagnetic emissions were collected in two low frequency bands of CH2 and CH1 instead of CH3 band, which means ULF band (0.01 - 1.0 Hz) is more sensitive than VLF band (1 - 9 kHz) at this TOA station.展开更多
Gas hydrate（GH） dissociates owing to thermal injection or pressure reduction from the well in gas/oil or GH exploitation. GH dissociation leads to, for example, decreases in soil strength, engineering failures such ...Gas hydrate（GH） dissociates owing to thermal injection or pressure reduction from the well in gas/oil or GH exploitation. GH dissociation leads to, for example, decreases in soil strength, engineering failures such as wellbore instabilities, and marine landslides. The FLAC3 D software was used to analyze the deformation of the soil stratum and vertical wells with GH dissociation. The effects of Young＇s modulus, internal friction angle, cohesion of the GH layer after dissociation, and the thickness of the GH layer on the deformation of soils were studied. It is shown that the maximum displacement in the whole soil stratum occurs at the interface between the GH layer and the overlayer. The deformation of the soil stratum and wells increases with decreases in the modulus, internal friction angle, and cohesion after GH dissociation. The increase in thickness of the GH layer enlarges the deformation of the soil stratum and wells with GH dissociation. The hydrostatic pressure increases the settlement of the soil stratum, while constraining horizontal displacement. The interaction between two wells becomes significant when the affected zone around each well exceeds half the length of the GH dissociation zone.展开更多
The flow pattern in a pipeline is a very important topic in petroleum exploitation. This paper is to classify the flow pattern of oil-gas-water flow in a pipeline by using BP neural network. The effects of different p...The flow pattern in a pipeline is a very important topic in petroleum exploitation. This paper is to classify the flow pattern of oil-gas-water flow in a pipeline by using BP neural network. The effects of different parameter combinations are investigated to find the most important ones. It is shown that BP neural network can be used in the analysis of the flow pattern of three-phase flow in pipelines. In most cases, the mean square error is large for the horizontal pipes. The optimized neuron number of the middle layer changes with conditions. So, we must changes the neuron number of the middle layer in simulation for any conditions to seek the best results. These conclusions can be taken as references for further study of the flow pattern of oil-gas-water in a pipeline.展开更多
Previous cases reported recurrent all oocytes in repeated cycles were arrested at MI failed to mature after culture and ICSI resulted in total nonfertilization. Ionomycin induced first PB extrusion in patients with re...Previous cases reported recurrent all oocytes in repeated cycles were arrested at MI failed to mature after culture and ICSI resulted in total nonfertilization. Ionomycin induced first PB extrusion in patients with recurrent maturation-resistant MI oocytes. ICSI combined with assisted oocyte activation (AOA) on MII oocytes matured in vitro resulted in abnormal fertilization with no further embryo cleavage potential. The objective of this work was to research if AOA helpful to fertilization for recurrent maturation-resistant MI oocytes. In this case, patient both cycles retrievaled immature MI oocytes characterized by absence perivitelline space (APVS). In the second cycle, ionomycin was used for AOA after MI oocyte perfomed ICSI, no fertilization again.展开更多
In view of the longer training and recognition time of plant leaf classifier,this paper proposes a method of blade recognition based on the combination of clonal selection algorithm and support vector machine.The meth...In view of the longer training and recognition time of plant leaf classifier,this paper proposes a method of blade recognition based on the combination of clonal selection algorithm and support vector machine.The method uses the blade geometry and texture features as the identification feature,building a blade recognition classifier based on support vector machine,in order to obtain the optimal kernel function parameter and the penalty factor,using cross validation characteristics of immune clonal selection algorithm to optimize the kernel function parameter and the penalty factor.Experimental results show that compared with BP neural network and other two methods,the proposed method has a higher recognition accuracy and training speed.展开更多
Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warmin...Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been investigated.Thus,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting ROL.We found that soil Eh in the rhizosphere was significantly higher than that of non-rhizosphere.Elevated CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)concentration.Under elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,respectively.We also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root ROL.Under elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,respectively.Warming had no effect on soil Eh and rice root ROL.While warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,respectively.There was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration significantly.Our study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+).展开更多
Background:LY01005(Goserelin acetate sustained-release microsphere injection)is a modified gonadotropin-releasing hormone(GnRH)agonist injected monthly.This phase III trial study aimed to evaluated the efficacy and sa...Background:LY01005(Goserelin acetate sustained-release microsphere injection)is a modified gonadotropin-releasing hormone(GnRH)agonist injected monthly.This phase III trial study aimed to evaluated the efficacy and safety of LY01005 in Chinese patients with prostate cancer.Methods:We conducted a randomized controlled,open-label,non-inferiority trial across 49 sites in China.This study included 290 patients with prostate cancer who received either LY01005 or goserelin implants every 28 days for three injections.The primary efficacy endpoints were the percentage of patients with testosterone suppression≤50 ng/dL at day 29 and the cumulative probability of testosterone≤50 ng/dL from day 29 to 85.Non-inferiority was prespecified at a margin of-10%.Secondary endpoints included significant castration(≤20 ng/dL),testosterone surge within 72 h following repeated dosing,and changes in luteinizing hormone,follicle-stimulating hormone,and prostate specific antigen levels.Results:On day 29,in the LY01005 and goserelin implant groups,testosterone concentrations fell below medical-castration levels in 99.3%(142/143)and 100%(140/140)of patients,respectively,with a difference of-0.7%(95%confidence interval[CI],-3.9%to 2.0%)between the two groups.The cumulative probabilities of maintaining castration from days 29 to 85 were 99.3%and 97.8%,respectively,with a between-group difference of 1.5%(95%CI,-1.3%to 4.4%).Both results met the criterion for non-inferiority.Secondary endpoints were similar between groups.Both treatments were well-tolerated.LY01005 was associated with fewer injection-site reactions than the goserelin implant(0%vs.1.4%[2/145]).Conclusion:LY01005 is as effective as goserelin implants in reducing testosterone to castration levels,with a similar safety profile.Trial registration:ClinicalTrials.gov,NCT04563936.展开更多
Virtual reality(VR)and augmented reality(AR)technologies have become increasingly important instruments in the field of art education as information technology develops quickly,transforming the conventional art educat...Virtual reality(VR)and augmented reality(AR)technologies have become increasingly important instruments in the field of art education as information technology develops quickly,transforming the conventional art education approach.The present situation,benefits,difficulties,and potential development tendencies of VR and AR technologies in art education will be investigated in this study.By means of literature analysis and case studies,this paper presents the fundamental ideas of VR and AR technologies together with their several uses in art education,namely virtual museums,interactive art production,art history instruction,and distant art cooperation.The research examines how these technologies might improve students’immersion,raise their learning motivation,and encourage innovative ideas and multidisciplinary cooperation.Practical application concerns including technology costs,content production obstacles,user acceptance,privacy,and ethical questions also come under discussion.At last,the article offers ideas and suggestions to help VR and AR technologies be effectively integrated into art education through teacher training,curriculum design,technology infrastructure development,and multidisciplinary cooperation.This study offers useful advice for teachers of art as well as important references for legislators and technology developers working together to further the creative growth of art education.展开更多
The aim of this experiment was to determine the impacts of climate change on soil profile concentrations and diffusion effluxes of methane in a rice-wheat annual rotation ecosystem in Southeastern China. We initiated ...The aim of this experiment was to determine the impacts of climate change on soil profile concentrations and diffusion effluxes of methane in a rice-wheat annual rotation ecosystem in Southeastern China. We initiated a field experiment with four treatments：ambient conditions（CKs）, CO2 concentration elevated to - 500 μmol/mol（FACE）,temperature elevated by ca. 2°C（T） and combined elevation of CO2 concentration and temperature（FACE ＋ T）. A multilevel sampling probe was designed to collect the soil gas at four different depths, namely, 7 cm, 15 cm, 30 cm and 50 cm. Methane concentrations were higher during the rice season and decreased with depth, while lower during the wheat season and increased with depth. Compared to CK, mean methane concentration was increased by 42%, 57% and 71% under the FACE, FACE ＋ T and T treatments, respectively, at the 7 cm depth during the rice season（p 〈 0.05）. Mean methane diffusion effluxes to the 7 cm depth were positive in the rice season and negative in the wheat season, resulting in the paddy field being a source and weak sink, respectively. Moreover, mean methane diffusion effluxes in the rice season were 0.94, 1.19 and 1.42 mg C/（m^2·hr） in the FACE,FACE ＋ T and T treatments, respectively, being clearly higher than that in the CK. The results indicated that elevated atmospheric CO2 concentration and temperature could significantly increase soil profile methane concentrations and their effluxes from a rice-wheat field annual rotation ecosystem（p 〈 0.05）.展开更多
Hydraulic collecting and pipe transportation are regarded as an efficient way for exploiting submarine mineral resources such as the manganese nodules and ores.Coarse particles on the surface of the sea bed are sucked...Hydraulic collecting and pipe transportation are regarded as an efficient way for exploiting submarine mineral resources such as the manganese nodules and ores.Coarse particles on the surface of the sea bed are sucked by a pipe during the mining and crushing of the mineral.In this paper,the critical suction velocity for lifting the coarse particles is investigated through a series of laboratory experiments,and the solid-liquid two-phase flow characteristics are obtained.Based on the dimensional analysis,the geometric similarity is found between actual exploitation process and model test with the same kind of material.The controlling dimensionless parameters such as the hydraulic collecting number,the relative coarse particle diameter,the relative suction height,and the density ratio are deduced and discussed.The results show that the logarithm in base 10 of the hydraulic collecting number increases approximately linearly with the increase of the relative suction height,while decreases with the relative particle diameter.A fitting formula for predicting the critical suction velocity is presented according to the experimental results.展开更多
Global warming is an increasingly serious ecological problem,we examined how the active autotrophic microbes in paddy soils respond to the elevated CO_(2) and temperature.Here we employed stable isotope probing(SIP)to...Global warming is an increasingly serious ecological problem,we examined how the active autotrophic microbes in paddy soils respond to the elevated CO_(2) and temperature.Here we employed stable isotope probing(SIP)to label the active bacteria using the soil samples from a fully factorial Simulated Climate Change(SCC)field experiment where soils were exposed to ambient CO_(2) and temperature,elevated temperature,elevated CO_(2),and both elevated CO_(2) and temperature.Around 28.9% of active OTUs belonged to ammonia-oxidizing bacteria(AOB)and nitrite-oxidizing bacteria(NOB).Nitrosospira taxa was dominant in all soils and 80.4% of carbon-fixing bacteria under elevated temperature were classified as Nitrosomonas nitrosa.While no labeled NOBs were detected when temperature or CO_(2) were elevated independently,diverse NOBs were detected in the ambient conditions.We found that elevated CO_(2) and temperature had contrasting effects on microbial community composition,while relatively small changes were observed when CO_(2) and temperature were elevated simultaneously.Summarily these results suggest that carbon-fixing bacteria can respond positively to elevated CO_(2) concentrations,but when it’s accompanied with increase in the temperature this positive response could be weakened.Multiple abiotic factors thus need to be considered when predicting how microbial communities will respond to multiple climatic factors.展开更多
Although various shape memory polymers(SMPs)or diverse applications have been widely reported,the SMPs based on rubbers have been rarely realized due to the low triggering temperature of rubbers.In another aspect,the ...Although various shape memory polymers(SMPs)or diverse applications have been widely reported,the SMPs based on rubbers have been rarely realized due to the low triggering temperature of rubbers.In another aspect,the SMPs based on sustainable substances are highly desired for the growing shortage in fossil resources.In the present study,we accordingly developed the sustainable SMPs with tunable triggering temperature,based on natural rubber(NR)and ferulic acid(FA)as the raw materials.Specifically,the SMPs are based on a crosslinked network of epoxidized natural rubber(ENR)crosslinked by in situ formed zinc ferulate(ZDF)via oxa-Michael reaction.The excellent shape memory effect(SME)is found in these SMPs,as evidenced by the high fixity/recovery ratio and the tunable triggering temperature.With the incorpora-tion of natural halloysite nanotubes(HNTs),the stress and recovery rate of the SMPs are found to be tunable,which widens the application of this kind of SMPs.The combination of adoption of sustainable raw materials,and the excellent and tunable SME makes these SMPs potentially useful in many applications,such as various actuators and heat-shrinkable package materials.展开更多
Recently,lead-free all-inorganic halide perovskites have attracted great interest because they not only have the merits of the halide perovskite family,but also are non-toxic.However,the commercialization of lead-free...Recently,lead-free all-inorganic halide perovskites have attracted great interest because they not only have the merits of the halide perovskite family,but also are non-toxic.However,the commercialization of lead-free allinorganic perovskites is restricted by their relatively low performances,which are usually caused by the fabrication methods and undesirable interfaces between the active layer and carrier transport layers.Herein,we demonstrate a solution-processed route for high-quality Ag_(2)BiI_(5) lead-free perovskite film by adopting ideal electron transport material SnO_(2)and a carbon electrode.By optimizing the fabrication process and tailoring the composition of the perovskite active layer,a high-performance photodetector(PD)with an FTO∕SnO_(2)∕Ag_(2)BiI_(5)∕carbon structure PD is first fabricated,which shows good self-powered performance with a detectivity of as high as 5.3×10^(12)Jones and a linear dynamic range of up to 138 d B,which are better than those of the reported Pb-free perovskite PDs and comparable to high-performance Pb-based perovskite PDs.In addition,our unpackaged PDs show good light,thermal,and storage stability in air.Our results provide a special route for the development of lead-free perovskite devices in an environmentally friendly field.展开更多
基金supported by the Key Forestry Public Welfare Project of China(201504105)the National Key Research and Development Program of China(2017YFD0600700)the Agricultural Science and Technology Independent Innovation Funds of Jiangsu Province[CX(16)1005].
文摘Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution.
基金Supported by 2016 Key Business Project of Jiangsu Meteorological Bureau(20161122)
文摘The spike-grain structure and yield data of winter wheat observed at 10 winter wheat observation stations in Jiangsu agrometeorological observation stations in the China Meteorological Observation Network were used to design the assessment model and evaluation criteria of the effects of climate change on spikegrain structure and yield of winter wheat. The linear regression method was used to determine the parameters of the assessment model,and the climate fact extrapolation method was used to determine future climate change scenarios. The effects of climate change on spike-grain structure and yield of winter wheat in Jiangsu Province were calculated and analyzed finally. The results showed that with the climate change,the meteorological conditions during the growth and development of winter wheat changed,which caused the number of effective spikes to decrease,and the number of grains per spike and thousand-grain weight to increase,and this new type of spike-grain structure combination was beneficial to the increase of the unit yield of winter wheat. The variations of meteorological elements caused by climate change during winter wheat growth and development had different effects on spike-grain structure at different growth stages. The spike-grain structure had an "increasing-decreasing" periodic variation with the growth period overall,with a period of one to three stages. The relationship between winter wheat growth and development and meteorological conditions can be adjusted in real time through stress-resistant cultivation techniques to achieve the high-yield and high-quality cultivation target of winter wheat production.
文摘In this paper, electromagnetic emissions recorded by a borehole TOA installment with three observing channels of CH1 (0.01 - 0.1 Hz), CH2 (0.1 - 1.0 Hz) and CH3 (1 - 9 kHz) before four large earthquakes with magnitudes more than 8.0 have been depicted. These abnormities present different fluctuating processes from one another. For the Wenchuan MS 8.0 earthquake on 12 May 2008, the nearest one among these four events and only 660 km from the TOA station, electromagnetic information appeared at least 5 months ago in two low frequency bands of CH1 and CH2 and it was subjected to an obvious fluctuating process with several developing stages: initial information, intensive anomaly and large amplitude signals. The typical pulse-like emissions in CH2 happened group by group with large various magnitudes, which can be of 10 mV in the climax period. While during this period, compatible wave-like information with little magnitudes also happened in CH1 channel and a few pulses in CH3. Anomalous emissions occurred about 4 months prior to the 25 April 2015 Nepal MS 8.1 event, 1560 km away from the TOA station. The abnormal information in CH2 also appeared group by group but with small various magnitudes, more than 2 mV during their climax. This process is also effective for the Sumatra MS 8.9 earthquake on 26 December 2004, 2500 km from the borehole TOA, only with a different duration of 2 months and less magnitudes of 0.1 mV in CH1 and 1 mV in CH2 in this case. However, there is no obvious fluctuation and only small constant amplitude signals being ~0.15 mV appeared during 2 weeks before the Japan MS 9.0 earthquake on 11 March 2011. It is the farthest one among these four events and beyond 4000 km from the observing station. So, we can make a conclusion that there is a near relationship between the properties of the abnormities associated with these four earthquakes, such as amplitudes, duration and signal types, and the distances from TOA station: on one hand, the amplitude and duration decreases as the distance increases;on the other hand, there is an evolution for emission properties from complex various magnitude signals to single equal magnitude ones as the distance changes to be far. However, one common feature of the anomalous information related to these four events is that almost electromagnetic emissions were collected in two low frequency bands of CH2 and CH1 instead of CH3 band, which means ULF band (0.01 - 1.0 Hz) is more sensitive than VLF band (1 - 9 kHz) at this TOA station.
基金supported by the National Natural Science Foundation of China (Grants 11272314, 51239010, 41376078)a joint project of the Chinese National Petroleum Corporation and the Chinese Academy of Sciences (Grant 2015A-4813)a project of the China Geological Survey (Grant GZH201100311)
文摘Gas hydrate（GH） dissociates owing to thermal injection or pressure reduction from the well in gas/oil or GH exploitation. GH dissociation leads to, for example, decreases in soil strength, engineering failures such as wellbore instabilities, and marine landslides. The FLAC3 D software was used to analyze the deformation of the soil stratum and vertical wells with GH dissociation. The effects of Young＇s modulus, internal friction angle, cohesion of the GH layer after dissociation, and the thickness of the GH layer on the deformation of soils were studied. It is shown that the maximum displacement in the whole soil stratum occurs at the interface between the GH layer and the overlayer. The deformation of the soil stratum and wells increases with decreases in the modulus, internal friction angle, and cohesion after GH dissociation. The increase in thickness of the GH layer enlarges the deformation of the soil stratum and wells with GH dissociation. The hydrostatic pressure increases the settlement of the soil stratum, while constraining horizontal displacement. The interaction between two wells becomes significant when the affected zone around each well exceeds half the length of the GH dissociation zone.
文摘The flow pattern in a pipeline is a very important topic in petroleum exploitation. This paper is to classify the flow pattern of oil-gas-water flow in a pipeline by using BP neural network. The effects of different parameter combinations are investigated to find the most important ones. It is shown that BP neural network can be used in the analysis of the flow pattern of three-phase flow in pipelines. In most cases, the mean square error is large for the horizontal pipes. The optimized neuron number of the middle layer changes with conditions. So, we must changes the neuron number of the middle layer in simulation for any conditions to seek the best results. These conclusions can be taken as references for further study of the flow pattern of oil-gas-water in a pipeline.
文摘Previous cases reported recurrent all oocytes in repeated cycles were arrested at MI failed to mature after culture and ICSI resulted in total nonfertilization. Ionomycin induced first PB extrusion in patients with recurrent maturation-resistant MI oocytes. ICSI combined with assisted oocyte activation (AOA) on MII oocytes matured in vitro resulted in abnormal fertilization with no further embryo cleavage potential. The objective of this work was to research if AOA helpful to fertilization for recurrent maturation-resistant MI oocytes. In this case, patient both cycles retrievaled immature MI oocytes characterized by absence perivitelline space (APVS). In the second cycle, ionomycin was used for AOA after MI oocyte perfomed ICSI, no fertilization again.
文摘In view of the longer training and recognition time of plant leaf classifier,this paper proposes a method of blade recognition based on the combination of clonal selection algorithm and support vector machine.The method uses the blade geometry and texture features as the identification feature,building a blade recognition classifier based on support vector machine,in order to obtain the optimal kernel function parameter and the penalty factor,using cross validation characteristics of immune clonal selection algorithm to optimize the kernel function parameter and the penalty factor.Experimental results show that compared with BP neural network and other two methods,the proposed method has a higher recognition accuracy and training speed.
基金supported by the National Natural Science Foundation of China (No.42277328)the Sino-German Mobility Program (No.M-0105)。
文摘Soil redox potential(Eh)plays an important role in the biogeochemical cycling of soil nutrients.Whereas its effect soil process and nutrients'availability under elevated atmospheric CO_(2) concentration and warming has seldom been investigated.Thus,in this study,a field experiment was used to elucidate the effect of elevated CO_(2) concentration and warming on soil Eh,redox-sensitive elements and root radial oxygen loss(ROL).We hypothesized elevated CO_(2) and warming could alter soil Eh by promoting or inhibiting ROL.We found that soil Eh in the rhizosphere was significantly higher than that of non-rhizosphere.Elevated CO_(2) enhanced soil Eh by 11.5%,which corresponded to a significant decrease in soil Fe^(2+)and Mn^(2+)concentration.Under elevated CO_(2),the concentration of Fe^(2+)and Mn^(2+)decreased by 14.7%and 13.7%,respectively.We also found that elevated CO_(2) altered rice root aerenchyma structure and promoted rice root ROL.Under elevated CO_(2),rice root ROL increased by 79.5%and 112.2%for Yangdao 6 and Changyou 5,respectively.Warming had no effect on soil Eh and rice root ROL.While warming increased the concentration of Mn^(2+)and SO_(4)^(2-)by 4.9%and 19.3%,respectively.There was a significant interaction between elevated CO_(2) and warming on Fe^(2+)and Mn^(2+).Under elevated CO_(2),warming had no effect on the concentration of Fe^(2+)but decreased Mn^(2+)concentration significantly.Our study demonstrated that elevated atmospheric CO_(2) in the future could increase soil Eh by promoting rice root ROL,which will alter some soil nutrients'availability,such as Fe^(2+)and Mn^(2+).
文摘Background:LY01005(Goserelin acetate sustained-release microsphere injection)is a modified gonadotropin-releasing hormone(GnRH)agonist injected monthly.This phase III trial study aimed to evaluated the efficacy and safety of LY01005 in Chinese patients with prostate cancer.Methods:We conducted a randomized controlled,open-label,non-inferiority trial across 49 sites in China.This study included 290 patients with prostate cancer who received either LY01005 or goserelin implants every 28 days for three injections.The primary efficacy endpoints were the percentage of patients with testosterone suppression≤50 ng/dL at day 29 and the cumulative probability of testosterone≤50 ng/dL from day 29 to 85.Non-inferiority was prespecified at a margin of-10%.Secondary endpoints included significant castration(≤20 ng/dL),testosterone surge within 72 h following repeated dosing,and changes in luteinizing hormone,follicle-stimulating hormone,and prostate specific antigen levels.Results:On day 29,in the LY01005 and goserelin implant groups,testosterone concentrations fell below medical-castration levels in 99.3%(142/143)and 100%(140/140)of patients,respectively,with a difference of-0.7%(95%confidence interval[CI],-3.9%to 2.0%)between the two groups.The cumulative probabilities of maintaining castration from days 29 to 85 were 99.3%and 97.8%,respectively,with a between-group difference of 1.5%(95%CI,-1.3%to 4.4%).Both results met the criterion for non-inferiority.Secondary endpoints were similar between groups.Both treatments were well-tolerated.LY01005 was associated with fewer injection-site reactions than the goserelin implant(0%vs.1.4%[2/145]).Conclusion:LY01005 is as effective as goserelin implants in reducing testosterone to castration levels,with a similar safety profile.Trial registration:ClinicalTrials.gov,NCT04563936.
文摘Virtual reality(VR)and augmented reality(AR)technologies have become increasingly important instruments in the field of art education as information technology develops quickly,transforming the conventional art education approach.The present situation,benefits,difficulties,and potential development tendencies of VR and AR technologies in art education will be investigated in this study.By means of literature analysis and case studies,this paper presents the fundamental ideas of VR and AR technologies together with their several uses in art education,namely virtual museums,interactive art production,art history instruction,and distant art cooperation.The research examines how these technologies might improve students’immersion,raise their learning motivation,and encourage innovative ideas and multidisciplinary cooperation.Practical application concerns including technology costs,content production obstacles,user acceptance,privacy,and ethical questions also come under discussion.At last,the article offers ideas and suggestions to help VR and AR technologies be effectively integrated into art education through teacher training,curriculum design,technology infrastructure development,and multidisciplinary cooperation.This study offers useful advice for teachers of art as well as important references for legislators and technology developers working together to further the creative growth of art education.
基金supported by and the Fundamental Research Funds for the National Science Foundation of China (No. 41171238)the Ministry of Science and Technology (No. 2013BAD11B01)+1 种基金the Central Universities (No. KYTZ201404)the Nonprofit Research Foundation for Agriculture (No. 200903003)
文摘The aim of this experiment was to determine the impacts of climate change on soil profile concentrations and diffusion effluxes of methane in a rice-wheat annual rotation ecosystem in Southeastern China. We initiated a field experiment with four treatments：ambient conditions（CKs）, CO2 concentration elevated to - 500 μmol/mol（FACE）,temperature elevated by ca. 2°C（T） and combined elevation of CO2 concentration and temperature（FACE ＋ T）. A multilevel sampling probe was designed to collect the soil gas at four different depths, namely, 7 cm, 15 cm, 30 cm and 50 cm. Methane concentrations were higher during the rice season and decreased with depth, while lower during the wheat season and increased with depth. Compared to CK, mean methane concentration was increased by 42%, 57% and 71% under the FACE, FACE ＋ T and T treatments, respectively, at the 7 cm depth during the rice season（p 〈 0.05）. Mean methane diffusion effluxes to the 7 cm depth were positive in the rice season and negative in the wheat season, resulting in the paddy field being a source and weak sink, respectively. Moreover, mean methane diffusion effluxes in the rice season were 0.94, 1.19 and 1.42 mg C/（m^2·hr） in the FACE,FACE ＋ T and T treatments, respectively, being clearly higher than that in the CK. The results indicated that elevated atmospheric CO2 concentration and temperature could significantly increase soil profile methane concentrations and their effluxes from a rice-wheat field annual rotation ecosystem（p 〈 0.05）.
基金The authors of this paper would like to thank the financial supports provided by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant XDA22000000).
文摘Hydraulic collecting and pipe transportation are regarded as an efficient way for exploiting submarine mineral resources such as the manganese nodules and ores.Coarse particles on the surface of the sea bed are sucked by a pipe during the mining and crushing of the mineral.In this paper,the critical suction velocity for lifting the coarse particles is investigated through a series of laboratory experiments,and the solid-liquid two-phase flow characteristics are obtained.Based on the dimensional analysis,the geometric similarity is found between actual exploitation process and model test with the same kind of material.The controlling dimensionless parameters such as the hydraulic collecting number,the relative coarse particle diameter,the relative suction height,and the density ratio are deduced and discussed.The results show that the logarithm in base 10 of the hydraulic collecting number increases approximately linearly with the increase of the relative suction height,while decreases with the relative particle diameter.A fitting formula for predicting the critical suction velocity is presented according to the experimental results.
基金supported by the National Key Research and Development Program of China(2017YFD0200805)the Special Fund for Agriculture Profession(20150312205)the Innovative Research Team Development Plan of the Ministry of Education of China(IRT_17R56).
文摘Global warming is an increasingly serious ecological problem,we examined how the active autotrophic microbes in paddy soils respond to the elevated CO_(2) and temperature.Here we employed stable isotope probing(SIP)to label the active bacteria using the soil samples from a fully factorial Simulated Climate Change(SCC)field experiment where soils were exposed to ambient CO_(2) and temperature,elevated temperature,elevated CO_(2),and both elevated CO_(2) and temperature.Around 28.9% of active OTUs belonged to ammonia-oxidizing bacteria(AOB)and nitrite-oxidizing bacteria(NOB).Nitrosospira taxa was dominant in all soils and 80.4% of carbon-fixing bacteria under elevated temperature were classified as Nitrosomonas nitrosa.While no labeled NOBs were detected when temperature or CO_(2) were elevated independently,diverse NOBs were detected in the ambient conditions.We found that elevated CO_(2) and temperature had contrasting effects on microbial community composition,while relatively small changes were observed when CO_(2) and temperature were elevated simultaneously.Summarily these results suggest that carbon-fixing bacteria can respond positively to elevated CO_(2) concentrations,but when it’s accompanied with increase in the temperature this positive response could be weakened.Multiple abiotic factors thus need to be considered when predicting how microbial communities will respond to multiple climatic factors.
基金This work was supported by the National Natural Science Foundation of China[grant number 51222301],[grant number 51473050],[grant number 51333003]Research Fund for the Doctoral Program of Higher Education of China[grant number 20130172110001]Fundamental Research Funds for the Central Universities[grant number 2014ZG0001].
文摘Although various shape memory polymers(SMPs)or diverse applications have been widely reported,the SMPs based on rubbers have been rarely realized due to the low triggering temperature of rubbers.In another aspect,the SMPs based on sustainable substances are highly desired for the growing shortage in fossil resources.In the present study,we accordingly developed the sustainable SMPs with tunable triggering temperature,based on natural rubber(NR)and ferulic acid(FA)as the raw materials.Specifically,the SMPs are based on a crosslinked network of epoxidized natural rubber(ENR)crosslinked by in situ formed zinc ferulate(ZDF)via oxa-Michael reaction.The excellent shape memory effect(SME)is found in these SMPs,as evidenced by the high fixity/recovery ratio and the tunable triggering temperature.With the incorpora-tion of natural halloysite nanotubes(HNTs),the stress and recovery rate of the SMPs are found to be tunable,which widens the application of this kind of SMPs.The combination of adoption of sustainable raw materials,and the excellent and tunable SME makes these SMPs potentially useful in many applications,such as various actuators and heat-shrinkable package materials.
基金National Natural Science Foundation of China(11874143,51972101)Natural Science Foundation of Hubei Province(2019CFB508)。
文摘Recently,lead-free all-inorganic halide perovskites have attracted great interest because they not only have the merits of the halide perovskite family,but also are non-toxic.However,the commercialization of lead-free allinorganic perovskites is restricted by their relatively low performances,which are usually caused by the fabrication methods and undesirable interfaces between the active layer and carrier transport layers.Herein,we demonstrate a solution-processed route for high-quality Ag_(2)BiI_(5) lead-free perovskite film by adopting ideal electron transport material SnO_(2)and a carbon electrode.By optimizing the fabrication process and tailoring the composition of the perovskite active layer,a high-performance photodetector(PD)with an FTO∕SnO_(2)∕Ag_(2)BiI_(5)∕carbon structure PD is first fabricated,which shows good self-powered performance with a detectivity of as high as 5.3×10^(12)Jones and a linear dynamic range of up to 138 d B,which are better than those of the reported Pb-free perovskite PDs and comparable to high-performance Pb-based perovskite PDs.In addition,our unpackaged PDs show good light,thermal,and storage stability in air.Our results provide a special route for the development of lead-free perovskite devices in an environmentally friendly field.
