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Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample 认领 引用 被引量：4
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作者 Chenxi Xu Yaru Zhao +4 位作者 Wenling An Qingyu Zhao Yucheng Liu Masaki Sano Takeshi Nakatsuka 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期167-174,共8页
Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ13C,δ18O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pret... Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ13C,δ18O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each proxy.Here,we developed a method by which each proxy can be measured in the same sample.First,the sample is polished for ring width meas-urement.After obtaining the ring width data,the sample is cut to form a 1-mm-thick wood plate.The sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray beam.Simultaneously,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,i.e.the density and the element content are obtained.Then,cellulose is isolated from the 1-mm wood plate by removal of lignin,and hemicellulose.After producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ13C,δ18O)analysis.Based on this method,RW,density,elemental composition,δ13C,and δ18O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research. 展开更多
关键词 Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes
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Reconstructing the annual precipitation variation since 1899 based on tree-ring width in the western Hedong sandy land of Ningxia 认领 引用 被引量：3
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作者 Wang, YaJun Gao, ShangYu +3 位作者 Ma, YuZhen Lu, RuiJie Sang, YanLi Meng, HongWei 《Journal of Arid Land》 SCIE 2010年第4期286-294,共9页
Based on the analysis of the correlation between the tree-ring width of Pinus tabulaeformis and the climate factors in the western Hedong sandy land of Ningxia, a conversion equation between the annual precipitation a... Based on the analysis of the correlation between the tree-ring width of Pinus tabulaeformis and the climate factors in the western Hedong sandy land of Ningxia, a conversion equation between the annual precipitation and the tree-ring width since 1899 was reconstructed. The results of cross verification indicated that the conversion equation is stable and the reconstructed results are reliable. The result of reconstructed annual precipitation showed the remarkable fluctuation of precipitation and dry-to-wet variation before the 1940s. The smaller fluctuation and high frequent changes of precipitation occurred during the period of 1940s-1980s and after the 1980s the change trend of the precipitation became high periodic extent and low frequent. The study found that there were some coincidences with the climate change in Changling Mountains, Helan Mountains and the east of Qilian Mountains. The relatively dry periods in the beginning of 20th century, 1920s to 1930s, the end of the 20th century and 2004 to 2006 in the western Hedong sandy land of Ningxia accelerated the desertification, while the relatively humid period during the periods of the 1910s-1920s, 1930s-1940s and 1990s is favorable to prevent and control the desertification, and to weaken the climate warming and drying. The periods of annual precipitation variation in the western Hedong sandy land of Ningxia since 1899 are approximately 2-4 years, 5-7 years and 10 years. 展开更多
关键词 Hedong sandy land of Ningxia tree-ring width annual precipitation correlation
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January to August temperature variability since 1776 inferred from tree-ring width of Pinus tabulaeformis in Helan Mountain 认领 引用 被引量：8
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作者 CAI Qiufang LIU Yu 《Journal of Geographical Sciences》 SCIE 2007年第3期293-303,共11页
Tree-ring standardized chronologies are developed by 78 cores collected from the eastern and western Helan Mountain. Statistical analysis shows that both the STD and RES chronologies correlate negatively with the temp... Tree-ring standardized chronologies are developed by 78 cores collected from the eastern and western Helan Mountain. Statistical analysis shows that both the STD and RES chronologies correlate negatively with the temperature of different periods of early half year, especially with January to August mean （JA） temperature, which means that JA temperature is one of the predominant limiting factors of tree growth in the Helan Mountain. Based on this analysis, we reconstructed JA temperature, and the explained variance is 43.3% （F=21.422, p〈0.001 ）. The comparatively high temperature periods in the reconstruction were： 1805-1818 1828-1857, 1899-1907, 1919-1931 and 1968-1995; and the comparatively low temperatu re periods happened in 1858-1872, 1883-1895 and 1935-1953. Ten-year moving average curve shows three slow uplifting trends： 1766-1853, 1862-1931 and 1944-1995. Each temperature increase was followed by a sudden temperature decrease about 10 years, that is to say, the JA temperature in the Helan Mountain is characterized by slow increase and sudden decrease. The 70- and 10.77-year periodicities detected in the temperature series correspond to the Gleissberg （80-year） and Schwabe （11-year） periodicities of solar activity respectively, the 2.11-2.62 years cycles are considered to be influenced by QBO （Quasi-Biennial-Oscillation） and the local environmental change. 展开更多
关键词 Helan Mountain tree-ring width temperature reconstruction
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Dynamics of moisture regime and its reconstruction from a tree-ring width chronology of Pinus sylvestris in the downstream basin of the Selenga River, Russia 认领 引用 被引量：1
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作者 Liliana BELOKOPYTOVA Dina ZHIRNOVA +1 位作者 Tatiana KOSTYAKOVA Elena BABUSHKINA 《Journal of Arid Land》 SCIE CSCD 2018年第6期877-891,共15页
Regional tree-ring width chronology of the Scots pine (Pinus sylvestris L.) was constructed from 8 sites in the forest-steppe belt situated in the foothills of the Selenga River basin, Russia. Moisture information con... Regional tree-ring width chronology of the Scots pine (Pinus sylvestris L.) was constructed from 8 sites in the forest-steppe belt situated in the foothills of the Selenga River basin, Russia. Moisture information contained in tree-ring width chronology was obtained through linear regression reconstruction models of annual August–July precipitation and annual water discharge of the Selenga River during the period 1767–2015. Comparison of the smoothed series allowed estimating long-term variation component of these moisture regime parameters with a high precision. At the same time, regional drought indices are less correlated with pine radial growth, because they have contribution of the other environmental variables, which are much less reflected in the tree-ring of the investigated pine forest stands. Reconstructed dynamic of the moisture regime parameters is supported by documental evident of many socially significant events in the regional history, such as crop failures caused by both droughts and floods, and catastrophic fire in the Irkutsk City in 1879. Also, dependence of the amount of precipitation in the study area on the atmospheric circulation in Central Asia is revealed to have a similar pattern with other regions, i.e., a negative relationship of precipitation with the development of large high atmospheric pressure area within its center in the Altai and Tianshan mountains. 展开更多
关键词 tree-ring width Pinus sylvestris climate hydrology precipitation reconstruction model
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Climatic response of Pinus sylvestris var. mongolica tree-ring width and precipitation reconstruction for the northern Greater Higgnan Mountains, China, since 1720 认领 引用
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作者 TongWen Zhang YuJiang Yuan +6 位作者 WenShou Wei RuiBo Zhang ShuLong Yu Feng Chen HuaMing Shang Li Qin ZiAng Fan 《Research in Cold and Arid Regions》 CSCD 2014年第6期546-555,共10页
August-June precipitation has been reconstructed back to AD 1720 for the northern Greater Higgnan Mountains, China, by use ofPinus sylvestris var. mongolica tree-ring width. The reconstruction explains the variance of... August-June precipitation has been reconstructed back to AD 1720 for the northern Greater Higgnan Mountains, China, by use ofPinus sylvestris var. mongolica tree-ring width. The reconstruction explains the variance of 39% in observed precipitation from 1973 to 2008. Some extremely dry/wet signals in historical documents and other precipitation reconstructions in previous studies are precisely captured in our reconstruction. Wet periods occurred during the periods of 1730 to 1746, 1789 to 1812, 1844 to 1903, 1920 to 1930, 1942 to 1961, and 1985 to 1998; while periods of 1747 to 1788, 1813 to 1843, 1904 to 1919, 1931 to 1941, and 1962 to 1984 were relatively dry. Power spectral and wavelet analyses demon- strated the existence of significant 24-year, 12-year, and 2-year cycles of variability. 展开更多
关键词 Greater Higgnan Mountains Pinus sylvestris var. mongolica tree-ring width precipitation reconstruction
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Species and elevation differences in climate responses of two conifers at the southern edge of the Tengger Desert:insights from tree-ring width and δ18O analyses 认领 引用
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作者 Qian Li Liang Jiao +6 位作者 Yarong Qin Xin Yuan Ruhong Xue Peng Zhang Xuge Wang Zhengdong Guo Le Zhang 《Journal of Plant Ecology》 SCIE CSCD 2025年第3期228-242,共15页
The physiological response mechanisms of trees to climate change are complex,particularly across varying elevations and among different tree species.In this study,we collected tree ring samples from two dominant conif... The physiological response mechanisms of trees to climate change are complex,particularly across varying elevations and among different tree species.In this study,we collected tree ring samples from two dominant conifer species(Picea crassifolia and Pinus tabuliformis)at three elevations at the edge of the Tengger Desert.We used tree-ring width(TRW)and tree ring oxygen isotopes(δ18OTR)to investigate how species and elevations affect their responses to climate change.Pearson’s correlation analysis and relative importance analysis were used to study the specific response processes of the two conifers to climate.The results showed that the TRW was mainly controlled by Standardized Precipitation Evapotranspiration Index(SPEI)during the growing season,which means that drought stress had the greatest effect on it.Andδ18OTRmainly responded to summer relative humidity.Both TRW andδ18OTRof P.crassifolia showed higher sensitivity to climate change.This sensitivity is largely attributed to the rapid uptake of precipitation by its developed shallow-rooted root system,which allows it to retain the precipitation signal in both TRW andδ18OTR.However,P.crassifolia may be more susceptible to drought stress and growth decline or even death in the context of a warming region.Our results are important for understanding the impacts of climate change on forest ecosystems using multiple indicators and developing corresponding ecological conservation measures. 展开更多
关键词 tree-ring width(TRW) tree-ring oxygen isotope(δ18OTR) elevation effect species effect climate effect
Water vapor signals and climate influences in northeastern China:insights from tree-rings and precipitation δ18O 认领 引用
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作者 Jiachuan Wang Qiang Li +12 位作者 Yu Liu Meng Ren Zichun Jia Yifan Wu Yang Xu Jeong-Wook Seo Changfeng Sun Huiming Song Qiufang Cai Zhenchuan Niu Wenxuan Pang Xiangyu Duan Wentai Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2026年第2期144-157,共14页
The northeastern permafrost region of China is one of the most vulnerable areas to climate warming in midlatitude areas.Despite this,the specific pathways of water vapor circulation and transport in this area remain p... The northeastern permafrost region of China is one of the most vulnerable areas to climate warming in midlatitude areas.Despite this,the specific pathways of water vapor circulation and transport in this area remain poorly understood.Additionally,there is ongoing debate on whether the oxygen isotope of precipitation(δ18Op)is primarily influenced by the temperature or the precipitation amount effects.Tree-ring samples were collected from various sites and tree species across the region,and 12 stable oxygen isotopes(δ18Oc)series constructed to investigate the water vapor signals embedded within.Our findings revealed consistentδ18Oc variations across different sites and species,reflecting relative humidity signals during the growing season(June to September)(r=−0.764,P<0.001,n=40).By applying an improved model to simulateδ18Op,a“temperature effect”was identified.Bothδ18Oc andδ18Op provided valuable insights into the regional water vapor circulation,withδ18Oc offering a stronger climate signal.A binary linear regression model further revealed thatδ18Op had a greater influence onδ18Oc than relative humidity.The regional climate is primarily driven by the East Asian summer monsoon and large-scale water vapor circulation associated with the El Niño-Southern Oscillation.Because of future warming and drying trends,trees in this region are expected to face increasing drought stress. 展开更多
关键词 Tree-ring oxygen isotopes Precipitation oxygen isotopes Improved model Permafrost region
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Relationships between tree-ring width index and NDVI of grassland in Delingha 认领 引用 被引量：13
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作者 HE Jicheng SHAO Xuemei 《Chinese Science Bulletin》 2006年第9期1106-1114,共9页
Using five well-replicated Qilian juniper(Sabina przewalskii Kom.)tree-ring width index se-ries,monthly normalized difference vegetation index(NDVI)of grassland,and climatic data from 1982 to 2001,the relationships be... Using five well-replicated Qilian juniper(Sabina przewalskii Kom.)tree-ring width index se-ries,monthly normalized difference vegetation index(NDVI)of grassland,and climatic data from 1982 to 2001,the relationships between tree-ring width index,NDVI of grassland,and climatic data were analyzed firstly.Then,the relationship between tree-ring width index and NDVI of grassland was explored.The re-sults showed that:(1)Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha.(2)There were sig-nificant relationships between five tree-ring width index series(DLH1-DLH5)and monthly NDVI of grassland from June to September,with the most significant relationship being between tree-ring width index series and NDVI of grassland in August.(3)The PC1(the first principal component derived from DLH1-DLH5 series)exhibited good agreement with monthly NDVI of grassland in the grass growth sea-son(from June to September)and the averaged NDVI in the growth season,which was attributed to their common responses to water-supply limit in Delingha.This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1. 展开更多
关键词 Delingha tree-ring width index grassland NDVI.
Adding a storage pool improves 3-PG tree-ring simulations 认领 引用
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作者 Yanfang Wang Liang Wei +4 位作者 Liheng Zhong Xizi Yu Pengtao Huang Fang Wang John D.Marshall 《Forest Ecosystems》 SCIE CAS CSCD 2025年第6期1319-1330,共12页
Tree rings provide long-term records of tree growth and climate changes,which makes them ideal benchmarks for forest modeling.Tree-ring information has greatly improved the reliability of 3-PG,which is one of the most... Tree rings provide long-term records of tree growth and climate changes,which makes them ideal benchmarks for forest modeling.Tree-ring information has greatly improved the reliability of 3-PG,which is one of the most commonly used process-based forest growth models.Here,we strengthen 3-PG's ability to simulate tree-ring width and stable carbon isotopes(δ13C)by enhancing its descriptions of tree physiology.The major upgrade was adding a carbon storage pool for tree-ring formation using stored carbohydrates.We also incorporated previous modifications(replacing the age modifier with a height modifier)of 3-PG and tested their efficacy in improving tree-ring simulations.We ran the model based on two grand fir(Abies grandis)stands.The updated model greatly improved the simulations for both tree-ring widths andδ13C.The results represent one of the best tree-ringδ13C simulations,which accurately captured the amplitude in annual variations ofδ13C.The correlations(R2)between simulations and observations reached 0.50 and 0.73 at two stands,respectively.The new model also greatly improved the simulations of raw tree-ring widths and detrended ring-width index(RWI).Because of better descriptions of tree physiology and more accurate simulations of tree rings than the previous model version,the updated 3-PG should provide more reliable simulations than previous 3-PG versions when tree-ring information is used as a benchmark in future studies. 展开更多
关键词 3-PG model Tree-ring simulation Tree height Carbon storage pool
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The CsTCP13-CsKNAT1-CsKNAT6 module regulates leaf width through influencing gibberellin biosynthesis in citrus 认领 引用
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作者 Donghai Liu Lele Chu +2 位作者 Haiqiang Liu Shariq Mahmood Alam Yongzhong Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2026年第5期1039-1052,共14页
Leaf morphology is an important agronomic trait that affects photosynthetic efficiency and plant architecture.Some KNOXI(ClassⅠKNOTTED1-LIKE HOMEOBOX)or CIN-TCP(CINCINNATA-LIKE TEOSINTE BRANCHED1,CYCLOIDEA,and PROLIF... Leaf morphology is an important agronomic trait that affects photosynthetic efficiency and plant architecture.Some KNOXI(ClassⅠKNOTTED1-LIKE HOMEOBOX)or CIN-TCP(CINCINNATA-LIKE TEOSINTE BRANCHED1,CYCLOIDEA,and PROLIFERATING CELL FACTORS)transcription factors control leaf development by influencing GA(gibberellin)content.However,the knowledge about their interaction in regulating leaf morphogenesis is still scarce,especially in woody fruit plants such as citrus.In this study,we found that the expression of CsTCP13(a citrus CIN-TCP gene)dramatically decreased with a decreasing leaf length-width ratio in citrus.Transiently silencing CsTCP13 in citrus produced wider leaves and significantly decreased Cs GA20ox1(a key citrus GA20-oxidase gene for GA biosynthesis)expression and GAs(GA3,GA4,and GA7)contents.Conversely,stable overexpression of CsTCP13 in tobacco generated narrower leaves and significantly increased GA20ox1 expression and GA1content;it also significantly shortened the distance between veins and reduced the number of epidermal cells per unit area of leaf.Moreover,transactivation assays showed that CsTCP13 had transcriptional activation,and yeast two-hybrid,split-luciferase complementation,and bimolecular fluorescence complementation assays confirmed that CsTCP13 interacted with CsKNAT1(a citrus KNOXI protein).Furthermore,yeast one-hybrid and dual-luciferase assays validated that CsTCP13 promoted while CsKNAT1 and its interacting protein CsKNAT6 inhibited Cs GA20ox1 expression by binding to its promoter.Interestingly,CsKNAT1 or the CsKNAT1-CsKNAT6 complex interacted with CsTCP13 to attenuate its promotion effect on Cs GA20ox1 expression.Taken together,our findings revealed a novel regulatory mechanism that CsTCP13 regulates citrus leaf width through directly influencing Cs GA20ox1 expression and then GA content,which can be negatively affected by the interaction with CsKNAT1 or the CsKNAT1-CsKNAT6 complex. 展开更多
关键词 Citrus Leaf width CIN-TCP Gibberellin GA20-oxidase KNOXI
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Detonation reaction zone width of CL-20-based aluminized explosive: machine learning prediction, theoretical calculation, and experimental characterization 认领 引用
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作者 Ruipeng Liu Wen Pan +3 位作者 Linjing Tang Xianzhen Jia Weiqiang Pang Xiaojun Feng 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第3期395-404,共10页
Investigating the detonation reaction zone structures of high explosives is significant for understanding detonation reaction mechanism.This study employed an integrated approach combining machine learning prediction,... Investigating the detonation reaction zone structures of high explosives is significant for understanding detonation reaction mechanism.This study employed an integrated approach combining machine learning prediction,theoretical calculation,and experimental characterization to determine the detonation reaction zone width of CL-20-based aluminized explosive.In this study,the detonation reaction zone refers to the reaction zone between the von Neumann(VN)peak and sonic point,which usually means the so-called detonation driving zone(DDZ).For the machine learning prediction,an ensemble model integrating Random Forest and Support Vector Regression was developed to predict the reaction zone width using a dataset of 19 publicly available samples.For the theoretical calculation,the Wood-Kirkwood(W-K)detonation theory model was utilized to implement numerical calculation of the reaction zone structures,incorporating chemical reaction kinetics to describe the detonation reaction progress.In experimental characterization,the Photon Doppler Velocimetry(PDV)was applied with LiF as the optical window to measure the particle velocity profile of detonation products and derive the reaction zone width.The results indicate that the reaction zone width values are 0.25 mm,0.28 mm,and 0.26 mm obtained from machine learning prediction,theoretical calculation,and experimental characterization,respectively.The corresponding velocities at the Chapman-Jouguet(CJ)point are 1,938 m/s,2,047 m/s,and 1,982 m/s,respectively.The maximum relative deviation in reaction zone width among three methods is approximately 7.7%,while that for CJ particle velocity is approximately 3.3%.These results from all three methods agree well within engineering error.This validates the effectiveness of integrating machine learning prediction,theoretical calculation and advanced experimental techniques for studying the detonation reaction zone structures of high explosives.This research provides insights into the detonation reaction mechanism and reaction zone characteristics of CL-20-based aluminized explosive. 展开更多
关键词 Detonation reaction zone width CL-20-Based aluminized explosive Machine learning Photon Doppler velocimetry(PDV) Theoretical calculation
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A statistical model for predicting rock avalanche runout using source area width from 63 representative cases 认领 引用
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作者 Rui-chen Chen Jian Chen +2 位作者 Sheng Ma Zi-ang Yan Qian Shi 《China Geology》 CAS CSCD 2026年第2期366-382,共17页
Developing predictive models for rock avalanche runout is crucial for hazard risk mitigation and management,while also deepening the understanding of rock avalanche dynamics.In this study,a database of 63 representati... Developing predictive models for rock avalanche runout is crucial for hazard risk mitigation and management,while also deepening the understanding of rock avalanche dynamics.In this study,a database of 63 representative rock avalanches was compiled,and the geometric characteristics of these events were analyzed.Traditional regression methods were compared with neural network regression(NNR)approaches to find the optimal model.Model parameters,loss functions,and evaluation metrics were examined to determine optimal configurations.Based on correlation analyses and model performance,this study recommends the use of source area width as an alternative to failure volume in runout prediction models,effectively addressing the common challenge of estimating avalanche volume.Ultimately,an NNR-based model,utilizing mean squared logarithmic error as the loss function and incorporating source area width and fall height as input parameters,was identified as the optimal approach.This model achieved prediction errors within a−50% to 50% range with 95.2% probability,yielding a mean absolute percentage error of 23.22% and an R2 of 0.85.These findings enhance rock avalanche prediction methodologies,providing more accurate tools for assessing the potential impact zones of destructive geological events. 展开更多
关键词 Runout prediction model Rock avalanche Traditional regression Neural network regression Source area width Fall height Loss functions Prediction errors Geological hazard prevention and control engineering
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Reconstruction of hydrological changes based on tree-ring data of the Haba River, northwestern China 认领 引用 被引量：12
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作者 zhang tongwen yuan yujiang +4 位作者 chen feng yu shulong zhang ruibo qin li jiang shengxia 《Journal of Arid Land》 SCIE CSCD 2018年第1期53-67,共15页
Reconstructing the hydrological change based on dendrohydrological data has important implications for understanding the dynamic distribution and evolution pattern of a given river. The widespread, long-living conifer... Reconstructing the hydrological change based on dendrohydrological data has important implications for understanding the dynamic distribution and evolution pattern of a given river. The widespread, long-living coniferous forests on the Altay Mountains provide a good example for carrying out the dendrohydrological studies. In this study, a regional composite tree-ring width chronology developed by Lariat sibirica Ledeb. and Picea obovata Ledeb. was used to reconstruct a 301-year annual （from preceding July to succeeding June） streamflow for the Haba River, which originates in the southern Altay Mountains, Xinjiang, China. Results indicated that the reconstructed streamflow series and the observations were fitting well, and explained 47.5% of the variation in the observed streamflow of 1957-2008. Moreover, floods and droughts in 1949-2000 were precisely captured by the streamflow reconstruction. Based on the frequencies of the wettest/driest years and decades, we identified the 19th century as the century with the largest occurrence of hydrological fluctuations for the last 300 years. After applying a 21-year moving average, we found five wet （1724-1758, 1780-1810, 1822-1853, 1931-1967, and 1986-2004） and four dry （1759-1779, 1811-1821, 1854-1930, and 1968-1985） periods in the streamflow reconstruction. Furthermore, four periods （1770-1796, 1816-1836, 1884-1949, and 1973-1997） identified by the streamflow series had an obvious increasing trend. The increasing trend of streamflow since the 1970s was the biggest in the last 300 years and coincided with the recent warming-wetting trend in northwestern China. A significant correlation between streamflow and precipitation in the Altay Mountains indicated that the streamflow reconstruction contained not only local, but also broad-scale, hydro-climatic signals. The 24-year, 12-year, and 2.2-4.5-year cycles of the reconstruction revealed that the streamflow variability of the Haba River may be influenced by solar activity and the atmosphere-ocean system. 展开更多
关键词 Larzx sibiffca Ledeb. Picea obovata Ledeb. streamflow reconstruction tree-ring width Altay Mountains
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Photoacoustic imaging and main lobe width analysis for enhancing microwave ablation monitoring of liver tissue 认领 引用
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作者 Min Wan Yameng Zhang +4 位作者 Shihao Tang Zhiyu Qian Fan Gao Yamin Yang Weitao Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2026年第2期129-140,共12页
Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the pot... Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the potential of photoacoustic imaging(PAI)in monitoring MWA by examining ex vivo porcine liver tissues.In this study,a comprehensive analysis of photoacoustic signals was performed to compare the main lobe width(MLW)between ablated and normal regions in porcine liver tissue.Histological staining with succinate dehydrogenase(SDH)and shear wave elastography(SWE)were employed to validate the changes in tissue elasticity after ablation.The analysis demonstrated a notable reduction in the MLW of the average A-lines in ablated tissues compared to nonablated regions(p<0.01).This reduction,attributed to increased tissue density and enhanced elasticity,indicates accelerated sound propagation in thermally ablated areas,which then serves as a critical parameter for mapping tissue characteristics.The reconstruction of the MLW distribution successfully delineated the ablated regions,and was consistent with the results of SDH staining and SWE.In addition,MLW-based imaging exhibited higher spatial resolution compared to SWE.Incorporating MLW analysis into PAI may be a promising strategy to improve the accuracy and effectiveness of MWA monitoring in clinical settings. 展开更多
关键词 Photoacoustic imaging main lobe width microwave ablation tissue density shear wave elastography
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Tree-ring-based drought variability in northern China over the past three centuries 认领 引用 被引量：6
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作者 ZENG Xueli LIU Yu +5 位作者 SONG Huiming LI Qiang CAI Qiufang FANG Congxi SUN Changfeng REN Meng 《Journal of Geographical Sciences》 SCIE CSCD 2022年第2期214-224,共11页
Droughts are the most frequent natural disaster in regions at the margins of the East Asian summer monsoon(EASM),which pose threats to agriculture,the economy,and human lives.However,the limitations of only approximat... Droughts are the most frequent natural disaster in regions at the margins of the East Asian summer monsoon(EASM),which pose threats to agriculture,the economy,and human lives.However,the limitations of only approximately 60 years of meteorological observations hamper our understanding of the characteristics and mechanisms of local hydroclimate.Trees growing in the marginal region of the EASM are usually sensitive to moisture variations and have played important roles in past hydroclimatic reconstructions.Here,a 303-year tree-ring-width chronology of Pinus tabulaeformis from Mt.Lama,which is located in the junction of the Liaoning Province and Inner Mongolia,China,was used to reconstruct the May-August Palmer drought severity index(PDSI)in the marginal region of the EASM.The transfer function explains 48.0%(or 47.2%after adjusting for the loss of the degrees of freedom)of the variance over the calibration period from 1946 to 2012.A spatial correlation analysis demonstrates that our PDSI reconstruction can represent the drought variability on the northernmost margin of the EASM.The winter Asian polar vortex area index showed a delayed impact on the summer EASM precipitation in the following year. 展开更多
关键词 tree-ring width Mt.Lama PDSI East Asian summer monsoon Asian polar vortex area index
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Tropical cyclone secondary eyewall width modulation:Differential impacts of surface environmental wind-vertical shear alignment and counter-alignment configurations 认领 引用
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作者 Yingying Zheng Qingqing Li Yufan Dai 《Atmospheric and Oceanic Science Letters》 CAS CSCD 2026年第1期7-13,共7页
This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shea... This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure. 展开更多
关键词 Tropical cyclone Secondary eyewall width Precipitation Vertical wind shear
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Age and red cell distribution width in pancreatic cystic neoplasms:A simple tool for preoperative malignancy risk stratification 认领 引用
17
作者 Shu-Qi Ren Yuan-Huan Han Chuang Cai 《World Journal of Gastrointestinal Surgery》 SCIE 2026年第1期458-461,共4页
The study conducted by Martli et al,on the preoperative risk stratification of malignant potential in pancreatic cystic neoplasms(PCNs),identifies age and red cell distribution width(RDW)as independent predictors.This... The study conducted by Martli et al,on the preoperative risk stratification of malignant potential in pancreatic cystic neoplasms(PCNs),identifies age and red cell distribution width(RDW)as independent predictors.This study offers a simple and cost-effective clinical tool for preoperative assessments.The significance lies in its integration of routine laboratory parameters with clinical features,effectively addressing the limitations associated with the accessibility and operator dependency of imaging and invasive diagnostic methods.However,factors such as the retrospective design,single-center setting,small sample size,and selection bias because of the inclusion of only surgical cases limit the generalizability of the findings.Future studies should emphasize multi-center prospective validation to further clarify the biological role of RDW in the malignant transformation of PCNs and to explore integrated models that combine RDW with imaging characteristics and molecular biomarkers,ultimately enhancing precision in individualized clinical decision-making. 展开更多
关键词 Pncreatic cystic neoplasms Red cell distribution width Age Preoperative assessment Malignancy risk stratification
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High red cell distribution width as a prognostic indicator in heart failure 认领 引用
18
作者 Sidhartha Gautam Senapati Azra Kothawala +1 位作者 Vibhor Ahluwalia Rupak Desai 《World Journal of Methodology》 2026年第1期327-336,共10页
BACKGROUND Red cell distribution width(RDW)measures the red blood cell size variation.Elevated RDW has been associated with various adverse health outcomes,including cardiovascular diseases.AIM To analyze current evid... BACKGROUND Red cell distribution width(RDW)measures the red blood cell size variation.Elevated RDW has been associated with various adverse health outcomes,including cardiovascular diseases.AIM To analyze current evidence on the prognostic significance of high RDW in patients with heart failure(HF).METHODS A comprehensive literature search was conducted across multiple databases,including PubMed,EMBASE,and Google Scholar,up to May 2024.Studies were included if they investigated the relationship between RDW levels and outcomes in HF patients.Compared to those in the lowest quartile.The primary outcome was all-cause mortality.Compared to those in the lowest quartile.Heterogeneity was assessed using the I2 statistic,we assessed the impact of individual studies on the overall estimate using a leave-one-out sensitivity analysis and publication bias was evaluated through a contour-enhanced funnel plot and Luis Furuya-Kanamori(LFK)index.RESULTS Seven studies,including a total of 11460 HF patients,were analyzed.The participants'mean age varied between 60 years and 80 years,with 6562(57.26%)in the lower quartile.Patients in the highest quartile of RDW(>15.21%)had a significantly increased risk of all-cause mortality,with an odds ratio of 1.84(95%CI:1.31-2.57,P<0.001),compared to those in the lowest quartile(RDW:14.1%-15.20%).There was significant variability in the included studies'results(I2=93%,P<0.01),as well as potential publication bias suggested by the high LFK index(8.47).Sensitivity analysis reinforced the robustness of these findings,showing that the results were not unduly influenced by any single study.CONCLUSION This meta-analysis confirms that high RDW is a robust predictor of adverse outcomes in patients with HF,highlighting its potential utility as a simple,cost-effective biomarker for risk stratification.Future research should focus on elucidating the mechanisms underlying this association and exploring the potential benefits of RDWguided therapeutic strategies in HF management. 展开更多
关键词 Red cell distribution width Heart failure All-cause mortality Red blood cell size variation Odds ratio
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Comparative Safety Analysis of Electric Wheelchairs Based on Sidewalk Width Differences 认领 引用
19
作者 Koji Sakai Tomoko Tonami Hiroshi Kanaji 《Psychology Research》 2026年第2期49-58,共10页
The purpose of this study was to clarify the effects of different sidewalk widths on the driving characteristics of electric wheelchairs and on the user’s psychology and safety.Eighteen participants drove electric wh... The purpose of this study was to clarify the effects of different sidewalk widths on the driving characteristics of electric wheelchairs and on the user’s psychology and safety.Eighteen participants drove electric wheelchairs on both wide and narrow sidewalks.Data collection included:(1)the number of cyclists and pedestrians passing by,(2)driving speed,(3)an 11-item questionnaire,and(4)a post-test ride interview.The results showed that the number of cyclists and pedestrians they passed and their driving speed were significantly higher on wide sidewalks.On the other hand,on narrow sidewalks,negative evaluations were frequently given,including the difficulty of avoiding steps,slopes,and utility poles,anxiety and psychological tension associated with pedestrian consideration,and difficulty in operation.These results indicate that sidewalk width is not just a physical space,but also an important environmental factor that strongly influences users’anxiety,operational burden,and distance adjustment from pedestrians.Creating a safe and comfortable mobility environment requires both improvements to sidewalk infrastructure and innovations in mobility devices. 展开更多
关键词 electric wheelchair WHILL sidewalk width safety test drive experiment
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Tree-ring response of Larix chinensis on regional climate and sea-surface temperature variations in alpine timberline in the Qinling Mountains 认领 引用 被引量：4
20
作者 Boqian Yan Jian Yu +2 位作者 Qijing Liu Lihua Wang Lile Hu 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期209-218,共10页
Tree-ring width chronologies of Larix chinensis were developed from the northern and southern slopes of the Qinling Mountains in Shaanxi Province,and climatic factors affecting the tree-ring widths of L.chinensis were... Tree-ring width chronologies of Larix chinensis were developed from the northern and southern slopes of the Qinling Mountains in Shaanxi Province,and climatic factors affecting the tree-ring widths of L.chinensis were examined.Correlation analysis showed that similar correlations between tree-ring width chronologies and climatic factors demonstrated that radial growth responded to climate change on both slopes.The radial growth of L.chinensis was mainly limited by temperature,especially the growing season.In contrast,both chronologies were negatively correlated with precipitation in May of the previous year and April of the current year.Spatial climate-correlation analyses with gridded land-surface climate data revealed that our tree-ring width chronologies contained a strong regional temperature signal over much of northcentral and eastern China.Spatial correlation with seasurface temperature fields highlights the influence of the Pacific Ocean,Indian Ocean,and North Atlantic Ocean.Wavelet coherence analysis indicated the existence of some decadal and interannual cycles in the two tree-ring width chronologies.This may suggest the influences of El Nin˜o-Southern Oscillation and solar activity on tree growth in the Qinling Mountains.These findings will help us understand the growth response of L.chinensis to climate change in the Qinling region,and they provide critical information for future climate reconstructions based on this species in semi-humid regions. 展开更多
关键词 Climate response Dendroclimatic Tree-ring width L.chinensis Qinling Mountains
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