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Subgenome asymmetry of gibberellins-related genes plays important roles in regulating rapid growth of bamboos
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作者 Ling Mao Cen Guo +9 位作者 Liang-Zhong Niu Yu-Jiao Wang Guihua Jin Yi-Zhou Yang Ke-Cheng Qian Yang Yang Xuemei Zhang Peng-Fei Ma De-Zhu Li Zhen-Hua Guo 《Plant Diversity》 2025年第1期68-81,共14页
Rapid growth is an innovative trait of woody bamboos that has been widely studied.However,the genetic basis and evolution of this trait are poorly understood.Taking advantage of genomic resources of 11 representative ... Rapid growth is an innovative trait of woody bamboos that has been widely studied.However,the genetic basis and evolution of this trait are poorly understood.Taking advantage of genomic resources of 11 representative bamboos at different ploidal levels,we integrated morphological,physiological,and transcriptomic datasets to investigate rapid growth.In particular,these bamboos include two large-sized and a small-sized woody species,compared with a diploid herbaceous species.Our results showed that gibberellin A1 was important for the rapid shoot growth of the world's largest bamboo,Dendrocalamus sinicus,and indicated that two gibberellins(GAs)-related genes,KAO and SLRL1,were key to the rapid shoot growth and culm size in woody bamboos.The expression of GAs-related genes exhibited significant subgenome asymmetry with subgenomes A and C demonstrating expression dominance in the large-sized woody bamboos while the generally submissive subgenomes B and D dominating in the small-sized species.The subgenome asymmetry was found to be correlated with the subgenome-specific gene structure,particularly UTRs and core promoters.Our study provides novel insights into the molecular mechanism and evolution of rapid shoot growth following allopolyploidization in woody bamboos,particularly via subgenome asymmetry.These findings are helpful for understanding of how polyploidization in general and subgenome asymmetry in particular contributed to the origin of innovative traits in plants. 展开更多
关键词 ALLOPOLYPLOIDS GAs DEGs Culm sizes rapid shoot growth Woody bamboos
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Rapid post-earthquake safety assessment of low-rise reinforced concrete structures
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作者 Koji Tsuchimoto Yasutaka Narazaki Billie F.Spencer,Jr. 《Earthquake Engineering and Engineering Vibration》 2025年第1期101-112,共12页
Many countries throughout the world have experienced large earthquakes,which cause building damage or collapse.After such earthquakes,structures must be inspected rapidly to judge whether they are safe to reoccupy.To ... Many countries throughout the world have experienced large earthquakes,which cause building damage or collapse.After such earthquakes,structures must be inspected rapidly to judge whether they are safe to reoccupy.To facilitate the inspection process,the authors previously developed a rapid building safety assessment system using sparse acceleration measurements for steel framed buildings.The proposed system modeled nonlinearity in the measurement data using a calibrated simplified lumped-mass model and convolutional neural networks(CNNs),based on which the buildinglevel damage index was estimated rapidly after earthquakes.The proposed system was validated for a nonlinear 3D numerical model of a five-story steel building,and later for a large-scale specimen of an 18-story building in Japan tested on the E-Defense shaking table.However,the applicability of the safety assessment system for reinforced concrete(RC)structures with complex hysteretic material nonlinearity has yet to be explored;the previous approach based on a simplified lumpedmass model with a Bouc-Wen hysteretic model does not accurately represent the inherent nonlinear behavior and resulting damage states of RC structures.This study extends the rapid building safety assessment system to low-rise RC moment resisting frame structures representing typical residential apartments in Japan.First,a safety classification for RC structures based on a damage index consistent with the current state of practice is defined.Then,a 3D nonlinear numerical model of a two-story moment frame structure is created.A simplified lumped-mass nonlinear model is developed and calibrated using the 3D model,incorporating the Takeda degradation model for the RC material nonlinearity.This model is used to simulate the seismic response and associated damage sensitive features(DSF)for random ground motion.The resulting database of responses is used to train a convolutional neural network(CNN)that performs rapid safety assessment.The developed system is validated using the 3D nonlinear analysis model subjected to historical earthquakes.The results indicate the applicability of the proposed system for RC structures following seismic events. 展开更多
关键词 rapid post-earthquake safety assessment ACCELERATION interstory drift angle damage sensitive feature convolutional neural network RC structure simplified non-linear analysis model Takeda degradation model
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Piezoelectrically Actuated Biomimetic Self-Contained Quadruped Bounding Robot
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作者 Thanhtam Ho Sangyoon Lee 《Journal of Bionic Engineering》 SCIE EI CSCD 2009年第1期29-36,共8页
This paper presents the development of a mesoscale self-contained quadruped mobile robot that employs two pieces of piezocomposite actuators for the bounding locomotion.The design of the robot leg is inspired by legge... This paper presents the development of a mesoscale self-contained quadruped mobile robot that employs two pieces of piezocomposite actuators for the bounding locomotion.The design of the robot leg is inspired by legged insects and animals, and the biomimetic concept is implemented in the robot in a simplified form,such that each leg of the robot has only one degree of freedom.The lack of degree of freedom is compensated by a slope of the robot frame relative to the horizontal plane.For the implementation of the self-contained mobile robot,a small power supply circuit is designed and installed on the robot.Experimental results show that the robot can locomote at about 50 mm·s^(-1)with the circuit on board,which can be considered as a significant step toward the goal of building an autonomous legged robot actuated by piezoelectric actuators. 展开更多
关键词 piezoelectric actuator quadruped robot bounding locomotion self-contained legged robot
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基于形状因子优化的RAPID算法对CFRP通孔损伤的研究
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作者 文学 董坤瑜 +3 位作者 杨炎 王文斌 陈奕宇 付为刚 《内燃机与配件》 2024年第16期14-16,共3页
在传统RAPID算法损伤成像中,形状因子β的设定通常是人为取值,其取值不同,成像的效果也不同,往往存在成像结果分散、分辨率较低的问题,因此提出了一种计算β值的新方法。通过ABAQUS有限元仿真,以CFRP层合板的通孔缺陷为检测对象,将形状... 在传统RAPID算法损伤成像中,形状因子β的设定通常是人为取值,其取值不同,成像的效果也不同,往往存在成像结果分散、分辨率较低的问题,因此提出了一种计算β值的新方法。通过ABAQUS有限元仿真,以CFRP层合板的通孔缺陷为检测对象,将形状因子优化后的RAPID算法与RAPID算法的损伤成像结果进行对比分析。结果表明,形状因子优化后的RAPID算法对缺陷定位结果的集中度更高,更能实现损伤位置的可视化。 展开更多
关键词 rapid 损伤成像 CFRP层合板 形状因子 定位
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Computer-Based Estimation of Spine Loading during Self-Contained Breathing Apparatus Carriage
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作者 WANG Shitan WANG Yunyi 《Journal of Donghua University(English Edition)》 CAS 2022年第4期373-378,共6页
Firefighters’low back disorders(LBDs)are closely related to excessive spine loading when using the self-contained breathing apparatus(SCBA)continuously.The purpose of this study was to quantify firefighters’spine lo... Firefighters’low back disorders(LBDs)are closely related to excessive spine loading when using the self-contained breathing apparatus(SCBA)continuously.The purpose of this study was to quantify firefighters’spine loading and evaluate the effects of strap lengths of SCBA on altering spine loading.Computer-based musculoskeletal models of three varying-strapped SCBA conditions and a control condition(CC)with no SCBA equipped were developed.The model was driven using three-dimensional(3 D)inertial motion capture data from twelve male subjects performing a walking task and the predicted ground reaction force(GRF).Electromyography(EMG)activities were also recorded to validate the results from the model.The 4 th-5 th lumbar vertebra(L4/L5)joint reaction forces,as well as erector spinae and rectus abdominis forces,were finally obtained.Results demonstrated that carrying SCBA significantly increased the compressive force and anteroposterior shear force at the spine.The risk of potential LBDs increased by about 17.77%.Dynamic balance of erector spinae and rectus abdominis contraction was also disturbed when carrying SCBA,indicating a higher risk of spine muscle strain.Adjustment of SCBA strap length was an efficient method to influence spine loading.The medium-fitting strap(MS)with a length of around 101 cm generated minimum joint reaction forces and achieved the optimum dynamic balance of spine muscle contraction,which was recommended for firefighters. 展开更多
关键词 FIREFIGHTER self-contained breathing apparatus(SCBA) low back disorder(LBD) musculoskeletal model
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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China 被引量:1
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作者 WANG Zili LU Chunyan +4 位作者 SU Yanlin SU Yue YU Qianru LI Wenzhe YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2024年第1期135-148,共14页
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human... Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development. 展开更多
关键词 winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City China
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On-site rapid detection of multiple pesticide residues in tea leaves by lateral flow immunoassay
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作者 Junxia Gao Tianyi Zhang +7 位作者 Yihua Fang Ying Zhao Mei Yang Li Zhao Ye Li Jun Huang Guonian Zhu Yirong Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第2期276-283,共8页
The application of pesticides (mostly insecticides and fungicides) during the tea-planting process will undoubtedly increase the dietary risk associated with drinking tea. Thus, it is necessary to ascertain whether pe... The application of pesticides (mostly insecticides and fungicides) during the tea-planting process will undoubtedly increase the dietary risk associated with drinking tea. Thus, it is necessary to ascertain whether pesticide residues in tea products exceed the maximum residue limits. However, the complex matrices present in tea samples comprise a major challenge in the analytical detection of pesticide residues. In this study, nine types of lateral flow immunochromatographic strips (LFICSs) were developed to detect the pesticides of interest (fenpropathrin, chlorpyrifos, imidacloprid, thiamethoxam, acetamiprid, carbendazim, chlorothalonil, pyraclostrobin, and iprodione). To reduce the interference of tea substrates on the assay sensitivity, the pretreatment conditions for tea samples, including the extraction solvent, extraction time, and purification agent, were optimized for the simultaneous detection of these pesticides. The entire testing procedure (including pretreatment and detection) could be completed within 30 min. The detected results of authentic tea samples were confirmed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), which suggest that the LFICS coupled with sample rapid pretreatment can be used for on-site rapid screening of the target pesticide in tea products prior to their market release. 展开更多
关键词 Lateral flow immunoassay rapid detection Pesticide multi-residue Tea matrix Sample rapid pretreatment
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Effectiveness of Music-Based Therapeutic Intervention on People with Dementia: A Rapid Review
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作者 Shreejeet Shrestha Samikshya Karmacharya +1 位作者 Yadav Prasad Joshi Prasa Shrestha 《Advances in Alzheimer's Disease》 CAS 2024年第2期35-47,共13页
Background: Dementia is a condition with progressive cognitive dysfunction and manifestation of both behavioral and psychosocial symptoms. Non-pharmacological measures such as music therapy are gaining importance sinc... Background: Dementia is a condition with progressive cognitive dysfunction and manifestation of both behavioral and psychosocial symptoms. Non-pharmacological measures such as music therapy are gaining importance since efficacy and safety of people with dementia have been questionable for pharmacological measures. Patient’s response to music is persistent even in the later stage of dementia. Aim: This rapid review aims to identify, analyze, evaluate, and summarize the best available evidence on the effectiveness of music-based therapeutic interventions among people with dementia. Method: CINAHL Cochrane Library, internet websites of rapid review producers, and reference lists were searched to identify articles for inclusion. Two reviewers independently screened the literature search results. Effectiveness, music-based therapeutic intervention, dementia, Alzheimer’s disease, systematic review and systematic review with meta-analysis terms were used to abstract data from included studies. Main Findings: 11 SRs and SRs with meta-analysis were reviewed which revealed positive effect of music therapy on five major outcomes with 9 studies effect on behavioral outcome, 6 studies with positive effect on psychosocial outcome reducing anxiety, 6 with improved cognition, 1 study revealed with improved quality of life and 1 study revealed effect on physiological outcomes. Conclusion: Music therapy has positive effect on treatment of dementia but further studies with larger sample size and specified to single intervention should be conducted to provide generalisable and precise results on this topic. 展开更多
关键词 DEMENTIA rapid Review Music Therapy BEHAVIORAL COGNITIVE Quality of Life
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Advantages of rapid solidification over casting of Mg-0.4Zn-1Y alloy
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作者 Drahomír Dvorský Shin-Ichi Inoue +7 位作者 Ayami Yoshida JiríKubásek Jan Duchon Esther de Prado Andrea Školáková Klára Hosová Petr Svora Yoshihito Kawamura 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第7期2847-2862,共16页
The Mg-Y-Zn magnesium alloy system is commonly recognized for its remarkable combination of high strength and ductility,achieved even with minimal amounts of alloying elements.This exceptional performance is attribute... The Mg-Y-Zn magnesium alloy system is commonly recognized for its remarkable combination of high strength and ductility,achieved even with minimal amounts of alloying elements.This exceptional performance is attributed to its unique microstructure,which includes Long-Period Stacking Ordered(LPSO)phases or the distinctive microstructure derived from the LPSO phase,referred to as the Mille-Feuille structure(MFS).This study systematically compares the traditional ingot metallurgy method with the rapid solidification technique,coupled with diverse heat treatments and extrusion processes.Microscopic analyses reveal variations in the presence of LPSO phases,Mille-Feuille structure,and grain size,leading to divergent mechanical and corrosion properties.The rapid solidification approach stands out,ensuring superior mechanical properties alongside a reasonable corrosion rate. 展开更多
关键词 rapid solidification LPSO KINK EXTRUSION Corrosion Ignition temperature
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Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the Detection of SARS-CoV-2 in Gabon
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作者 Samira Zoa Assoumou Ulrich Leger Davy Mouangala +6 位作者 Ludovic Mewono Davy-Christ Angoune Ndong Guy Paterne Malonga Mbembo Nely Meungang Alain Moutsinga Elvyre Anita Mbongo Kama Rodrigue Mintsa Nguema 《Advances in Infectious Diseases》 CAS 2024年第2期469-477,共9页
1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is... 1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to December 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission. 展开更多
关键词 SARS-CoV-2 rapid Diagnostic Test EVALUATION COVID-19 ANTIGEN Performance
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Photo-promoted rapid reconstruction induced alterations in active site of Ag@amorphous NiFe hydroxides for enhanced oxygen evolution reaction
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作者 Zhi Cai Mingyuan Xu +6 位作者 Yanhong Li Xinyan Zhou Kexin Yin Lidong Li Binbin Jia Lin Guo Hewei Zhao 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期210-220,共11页
The dynamic surface self-reconstruction behavior in local structure correlates with oxygen evolution reaction(OER)performance,which has become an effective strategy for constructing the catalytic active phase.However,... The dynamic surface self-reconstruction behavior in local structure correlates with oxygen evolution reaction(OER)performance,which has become an effective strategy for constructing the catalytic active phase.However,it remains a challenge to understand the mechanisms of reconstruction and to accomplish it fast and deeply.Here,we reported a photo-promoted rapid reconstruction(PRR)process on Ag nanoparticle-loaded amorphous Ni-Fe hydroxide nanosheets on carbon cloth for enhanced OER.The photogenerated holes generated by Ag in conjunction with the anodic potential contributed to a thorough reconstruction of the amorphous substrate.The valence state of unsaturated coordinated Fe atoms,which serve as active sites,is significantly increased,while the corresponding crystalline substrate shows little change.The different structural evolutions of amorphous and crystalline substrates during reconstruction lead to diverse pathways of OER.This PRR utilizing loaded noble metal nanoparticles can accelerate the generation of active species in the substrate and increase the electrical conductivity,which provides a new inspiration to develop efficient catalysts via reconstruction strategies. 展开更多
关键词 AG AMORPHOUS Ni-Fe hydroxide OER photo-promoted rapid reconstruction
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Alignment of Track Oscillations during Tropical Cyclone Rapid Intensification
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作者 Tong XIE Liguang WU +1 位作者 Yecheng FENG Jinghua YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期655-670,共16页
Recent studies on tropical cyclone(TC)intensity change indicate that the development of a vertically aligned TC circulation is a key feature of its rapid intensification(RI),however,understanding how vortex alignment ... Recent studies on tropical cyclone(TC)intensity change indicate that the development of a vertically aligned TC circulation is a key feature of its rapid intensification(RI),however,understanding how vortex alignment occurs remains a challenging topic in TC intensity change research.Based on the simulation outputs of North Atlantic Hurricane Wilma(2005)and western North Pacific Typhoon Rammasun(2014),vortex track oscillations at different vertical levels and their associated role in vortex alignment are examined to improve our understanding of the vortex alignment during RI of TCs with initial hurricane intensity.It is found that vortex tracks at different vertical levels oscillate consistently in speed and direction during the RI of the two simulated TCs.While the consistent track oscillation reduces the oscillation tilt during RI,the reduction of vortex tilt results mainly from the mean track before RI.It is also found that the vortex tilt is primarily due to the mean vortex track before and after RI.The track oscillations are closely associated with wavenumber-1 vortex Rossby waves that are dominant wavenumber-1 circulations in the TC inner-core region.This study suggests that the dynamics of the wavenumber-1 vortex Rossby waves play an important role in the regulation of the physical processes associated with the track oscillation and vertical alignment of TCs. 展开更多
关键词 tropical cyclone rapid intensification vortex tilt Rossby wave
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Combining first principles and machine learning for rapid assessment response of WO_(3) based gas sensors
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作者 Ran Zhang Guo Chen +4 位作者 Shasha Gao Lu Chen Yongchao Cheng Xiuquan Gu Yue Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第12期1765-1772,共8页
The rapid advancement of gas sensitive properties in metal oxides is crucial for detecting hazardous gases in industrial and coal mining environments.However,the conventional experimental trial and error approach pose... The rapid advancement of gas sensitive properties in metal oxides is crucial for detecting hazardous gases in industrial and coal mining environments.However,the conventional experimental trial and error approach poses significant challenges and resource consumption for the high throughput screening of gas sensitive materials.Consequently,this paper introduced a novel screening approach that integrates first principles with machine learning(ML)to rapidly predict the gas sensitivity of materials.Initially,a comprehensive database of multi-physical parameters was established by modeling various adsorption sites on the surface of WO3,which serves as a representative material.Since density functional theory(DFT)is one of the first principles,DFT calculations were conducted to derive essential multi-physical parameters,including bandgap,density of states(DOS),Fermi level,adsorption energy,and structural modifications resulting from adsorption.The collected data was subsequently utilized to develop a cor-relation model linking the multi-physical parameters to gas sensitive performance using intelligent algo-rithms.The model’s performance was assessed through receiver operating characteristic(ROC)curves,confusion matrices,and other evaluation metrics,ultimately achieving a prediction accuracy of 90%for identifying key features influencing gas adsorption performance.This proposed strategy for predicting the gas sensitive characteristics of materials holds significant potential for application in identifying addi-tional gas sensitive properties across various materials. 展开更多
关键词 Machine learning Density functional theory rapid assessment Gas sensor
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Old Pinus massoniana forests benefit more from recent rapid warming in humid subtropical areas of central-southern China
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作者 Wenxin Li Liangjun Zhu +4 位作者 Lianhua Zhu Mengdan Jing Censhi Qian Yu Zhu Paolo Cherubini 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期155-170,共16页
Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental conditions.Despite the importance of age-related growth responses on overall forest health and... Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental conditions.Despite the importance of age-related growth responses on overall forest health and management policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree species.In this study,we employed a den-drochronological method to examine the impact of rapid warming on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)Pinus mas-soniana forests across six sites in central-southern China.The normalized log basal area increment of trees in both age groups increased significantly following rapid warming in 1984.Trees in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth increases.Tree growth was more strongly influenced by temperature than by moisture,particularly in old forests.Spring tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young ones.Old forests had a significantly lower resistance to extreme drought but faster recovery compared to young forests.The“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warming-induced drought and heat stress.With ongoing warming,young forests also may initially experience a growth decline due to their heightened sensitivity to winter drought.Our findings underscore the importance of considering age-dependent changes in forest/tree growth response to warming in subtropical forest man-agement,particularly in the context of achieving“Carbon Peak&Carbon Neutrality”goals in China. 展开更多
关键词 Tree rings Pinus massoniana Age effects Drought resilience Subtropical forests rapid warming
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Rapid and real-time analysis of multi-component dissolved gas in seawater by Raman spectroscopy combined with continuous gas-liquid separator
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作者 Dewang Yang Wenhua Li +5 位作者 Lei Guo Yuhang Ji Yanzhe Gong Junwei Chu Libin Du Yongmei Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期146-153,共8页
Rapid and sensitive detection of dissolved gases in seawater is quite essential for the investigation of the global carbon cycle.Large quantities of in situ optical detection techniques showed restricted measurement e... Rapid and sensitive detection of dissolved gases in seawater is quite essential for the investigation of the global carbon cycle.Large quantities of in situ optical detection techniques showed restricted measurement efficiency,owing to the single gas sensor without the identification ability of multiple gases.In this work,a novel gas-liquid Raman detection method of monitoring the multi-component dissolved gases was proposed based on a continuous gas-liquid separator under a large difference of partial pressure.The limit of detection(LOD)of the gas Raman spectrometer could arrive at about 14 μl·L^(-1)for N_(2)gas.Moreover,based on the continuous gas-liquid separation process,the detection time of the dissolved gases could be largely decreased to about 200 s compared with that of the traditional detection method(30 min).Effect of equilibrium time on gas-liquid separation process indicated that the extracted efficiency and decay time of these dissolved gases was CO_(2)>O_(2)>N_(2).In addition,the analysis of the relationship between equilibrium time and flow speed indicated that the decay time decreased with the increase of the flow speed.The validation and application of the developed system presented its great potential for studying the components and spatiotemporal distribution of dissolved gases in seawater. 展开更多
关键词 Dissolved gas rapid quantitative analysis Gas-liquid separator Gas-liquid Raman spectroscopy
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Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems
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作者 Meng Wang Yi Gu +5 位作者 Mao-Lin Xiong Liang-Quan Ge Qing-Xian Zhang Guo-Qiang Zeng Heng Lu Sheng-Liang Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期1-12,共12页
Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are d... Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement chamber.To protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement method.To address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)conditions.In addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo simulations.On this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in water.Subsequent analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for radionuclides.The experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,respectively.These times are much shorter than the 90 min required by the conventional measurement method.Furthermore,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method considerably enhances the warning capacity of in situ online waterγ-spectrometry systems. 展开更多
关键词 Water radioactivity monitoring Dynamic detection efficiency rapid warning Activity estimation
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Rapid prediction of flow and concentration fields in solid-liquid suspensions of slurry electrolysis tanks
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作者 Tingting Lu Kang Li +4 位作者 Hongliang Zhao Wei Wang Zhenhao Zhou Xiaoyi Cai Fengqin Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2006-2016,共11页
Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension state.The computational fluid d... Slurry electrolysis(SE),as a hydrometallurgical process,has the characteristic of a multitank series connection,which leads to various stirring conditions and a complex solid suspension state.The computational fluid dynamics(CFD),which requires high computing resources,and a combination with machine learning was proposed to construct a rapid prediction model for the liquid flow and solid concentration fields in a SE tank.Through scientific selection of calculation samples via orthogonal experiments,a comprehensive dataset covering a wide range of conditions was established while effectively reducing the number of simulations and providing reasonable weights for each factor.Then,a prediction model of the SE tank was constructed using the K-nearest neighbor algorithm.The results show that with the increase in levels of orthogonal experiments,the prediction accuracy of the model improved remarkably.The model established with four factors and nine levels can accurately predict the flow and concentration fields,and the regression coefficients of average velocity and solid concentration were 0.926 and 0.937,respectively.Compared with traditional CFD,the response time of field information prediction in this model was reduced from 75 h to 20 s,which solves the problem of serious lag in CFD applied alone to actual production and meets real-time production control requirements. 展开更多
关键词 slurry electrolysis solid-liquid suspension computational fluid dynamics K-nearest neighbor algorithm rapid prediction
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Observation of the Effectiveness of Rapid Recovery Nursing on Lung Cancer Surgery Patients and Its Impact on Sleep Quality
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作者 Weiwei Chen Dandan Liu 《Journal of Cancer Therapy》 2024年第2期29-32,共4页
Objective: To investigate the nursing effects of rapid recovery care measures on lung cancer surgery patients. Methods: 42 cases of lung cancer surgery patients were divided into control group and study group, with 21... Objective: To investigate the nursing effects of rapid recovery care measures on lung cancer surgery patients. Methods: 42 cases of lung cancer surgery patients were divided into control group and study group, with 21 cases in each group. The sleep quality and postoperative recovery indicators were compared between the two groups. Results: The study group showed better results than the control group in terms of PSQI scores, venting time, extubation time, time to getting out of bed, and duration of antibiotic use, with P Conclusion: Rapid recovery nursing has a positive impact on improving sleep quality and promoting postoperative recovery in lung cancer surgery patients. 展开更多
关键词 rapid Recovery Nursing Lung Cancer Surgery Sleep Quality
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Nursing Effect of Rapid Rehabilitation Surgery Concept in Laparoscopic Surgery for Extrahepatic Bile Duct Stones
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作者 Haiying Cheng Linjun Ruan 《Journal of Biosciences and Medicines》 2024年第1期1-6,共6页
Objective: To explore the application value of rapid rehabilitation concept in patients with extrahepatic bile duct stones under laparoscopy during perioperative period. Methods: 90 patients with extrahepatic bile duc... Objective: To explore the application value of rapid rehabilitation concept in patients with extrahepatic bile duct stones under laparoscopy during perioperative period. Methods: 90 patients with extrahepatic bile duct stones treated in our hospital from January 2022 to February 2023 were selected as the research object and randomly divided into the study group and the control group. The control group was given routine care, and the observation group was given rapid surgical rehabilitation care. The postoperative anal exhaust time, first meal time, early activity time, pain time, abdominal drainage tube removal time, hospitalization time and complication rate were compared between the two groups. The independent sample T test was used for the measurement data, and the x<sup>2</sup> test was used for the counting data, and the difference was statistically significant (P Results: The postoperative anal exhaust time, first meal time, early activity time, pain time, abdominal drainage tube removal time and hospitalization time in the study group were shorter than those in the control group (all P Conclusion: The concept of rapid rehabilitation can significantly improve the perioperative nursing effect of patients with extrahepatic bile duct stones and accelerate their rehabilitation, which is worth improving and popularizing. 展开更多
关键词 rapid Rehabilitation Surgical Nursing LAPAROSCOPY Extrahepatic Bile Duct Stones
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Estimation of surface geometry on combustion characteristics of AP/HTPB propellant under rapid depressurization
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作者 Kaixuan Chen Zhenwei Ye +1 位作者 Xiaochun Xue Yonggang Yu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期546-558,共13页
The 2D sandwich model serves as a potent tool in exploring the influence of surface geometry on the combustion attributes of Ammonium perchlorate/Hydroxyl-terminated polybutadiene(AP/HTPB)propellant under rapid pressu... The 2D sandwich model serves as a potent tool in exploring the influence of surface geometry on the combustion attributes of Ammonium perchlorate/Hydroxyl-terminated polybutadiene(AP/HTPB)propellant under rapid pressure decay.The thickness of the sandwich propellant is derived from slicing the 3D random particle packing,an approach that enables a more effective examination of the micro-flame structure.Comparative analysis of the predicted burning characteristics has been performed with experimental studies.The findings demonstrate a reasonable agreement,thereby validating the precision and soundness of the model.Based on the typical rapid depressurization environment of solid rocket motor(initial combustion pressure is 3 MPa and the maximum depressurization rate is 1000 MPa/s).A-type(a flatter surface),B-type(AP recesses from the combustion surface),and C-type(AP protrudes from the combustion surface)propellant combustion processes are numerically simulated.Upon comparison of the evolution of gas-phase flame between 0.1 and 1 ms,it is discerned that the flame strength and form created by the three sandwich models differ significantly at the beginning stage of depressurization,with the flame structures gradually becoming harmonized over time.Conclusions are drawn by comparison extinction times:the surface geometry plays a pivotal role in the combustion process,with AP protrusion favoring combustion the most. 展开更多
关键词 AP/HTPB propellant BDP model rapid pressure decay Burning surface geometry
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