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Seasonal emission patterns of airborne phytoncides in temperate forests from autumn to early spring:a case study of Xishui National Forest Park(Yichun,Northeast China)
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作者 Hongda Cai Yitong Wang +6 位作者 Xianwen Huang Sen Zhang Yankun Liu Jian Zhang Dongmei Zhao Peng Zhao Xiuhua Zhao 《Journal of Forestry Research》 2026年第1期256-271,共16页
Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio ac... Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies. 展开更多
关键词 Phytoncides Seasonal variation Diurnal-nocturnal patterns Snowfall impact Emission patterns
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s... Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests. 展开更多
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Thermal stability design for flexural wave bandgap of metamaterial plates with perforated and pre-curved patterns
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作者 Qian GENG Xing ZHOU +3 位作者 Mengyang WANG Xiongwei YANG Zhushan SHAO Yueming LI 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期443-472,I0001-I0004,共34页
A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforat... A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforation can release part of the in-plane thermal expansion to weaken the softening effect of thermal stress.Introducing precurved components to the perforated structure will stop the decrement of the bandgap frequency in thermal environment,and even make the frequency higher with appropriate structural parameters.The bending stiffness of the heated plate is enhanced by the thermal deflection induced stiffening effect of the pre-curved components.The segmented pre-curved component presents a strong ability to resist the thermal influence on the flexural wave bandgap.A simplified model is established for the local structure of the precurved component.The theoretical calculations explain the thermally induced frequency increment of the bandgap and the discrepancy in the thermal response between the two pre-curved models.The transmittance of flexural wave validates the effectiveness of the proposed design. 展开更多
关键词 metamaterial plate flexural vibration bandgap PERFORATION pre-curved pattern thermal stability
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Unravelling tree diversity patterns and responses to environmental gradients in a tropical forest landscape of the Western Ghats
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作者 Naveen Babu Kanda Ashaq Ahmad Dar +2 位作者 Kurian Ayushi Ayyappan Narayanan Narayanaswamy Parthasarathy 《Plant Diversity》 2026年第1期92-106,共15页
Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the She... Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers ofα-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation inα-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems. 展开更多
关键词 Alpha diversity Beta diversity Machine learning Structural equation modeling Vegetation patterns Western Ghats
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Regional differences and formation mechanisms of watershed territorial space patterns evolution:A case study of the critical areas in the Pearl River Basin 被引量:2
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作者 LIN Shugao WANG Pengcheng +2 位作者 ZHU Peixin HUANG Ke LU Rucheng 《Journal of Geographical Sciences》 2025年第5期941-963,共23页
Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guang... Clarifying the mechanisms that control the evolution of territorial space patterns is essential for regulating and optimizing the geographical structure and processes related to sustainable development.Using the Guangdong and Guangxi sections of the Pearl River Basin as examples,the transfer-matrix method and standard deviation ellipse model were applied to characterize the evolution of territorial space patterns from 1990 to 2020.A trend surface analysis and the Theil index were used to analyze regional differences in the evolution process,and geodetectors were used to identify the underlying mechanisms of the changes.There were three key results.(1)In these critical areas of the Pearl River Basin,agricultural and ecological spaces have rapidly declined due to urban expansion,with transfers between these spaces dominating the evolution of territorial space patterns.Spatial pattern changes in the Guangdong section were more intense than in the Guangxi section.(2)Regional differences in urban space have decreased,whereas differences in agricultural and ecological spaces have intensified.Driven by socio-economic growth,the cross-regional transfers of territorial space have created a“high in the east,while low in the west”inter-regional difference,and a“high in the south,while low in the north”intra-regional difference shaped by natural conditions.The regional differences in space patterns were greater in Guangdong than in Guangxi.(3)The evolution of watershed territorial space patterns resulted from scale changes,locational shifts,structural reorganizations,and directional changes driven by multiple factors.Natural environment,social life,economic development,and policy factors played foundational,leading,key driving,and guiding roles,respectively.Additionally,the regional differences in the evolution of watershed territorial space patterns originated from the differential transmission of the influence of various factors affecting spatial evolution.Enhancing urban space efficiency,restructuring agricultural space,and optimizing ecological space are key strategies for building a complementary and synergistic territorial space pattern in the basin. 展开更多
关键词 territorial space patterns urban-agricultural-ecological space(UAES) formation mechanisms regionaldifferences Pearl River Basin
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Rising frequency of ozone-favorable synoptic weather patterns contributes to 2015-2022 ozone increase in Guangzhou 被引量:2
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作者 Nanxi Liu Guowen He +8 位作者 Haolin Wang Cheng He Haofan Wang Chenxi Liu Yiming Wang Haichao Wang Lei Li Xiao Lu Shaojia Fan 《Journal of Environmental Sciences》 2025年第2期502-514,共13页
Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examine... Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns(SWPs),however,the consistency of different classification methods is rarely examined.In this study,we apply two widely-used objective methods,the self-organizing map(SOM)and K-means clustering analysis,to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022.We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities.In the case of classifying six SWPs,the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods,and the difference in themean frequency of each SWP is less than 7%.The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature,lower cloud cover,relative humidity,and wind speed,and stronger subsidence compared to climatology mean.We find that during 2015-2022,the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 days/year,faster than the increases in the ozone exceedance days(3.0 days/year).The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6.In particular,the significant increase in ozone-favorable SWPs in 2022,especially the Subtropical High type which typically occurs in September,is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022.Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou. 展开更多
关键词 Ozone(O_(3)) Objective weather classification methods Synoptic weather patterns Trends GUANGZHOU
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Identification and distribution patterns of the ultra-deep small-scale strike-slip faults based on convolutional neural network in Tarim Basin,NW China 被引量:1
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作者 Hao Li Jun Han +4 位作者 Cheng Huang Lian-Bo Zeng Bo Lin Ying-Tao Yao Yi-Chen Song 《Petroleum Science》 2025年第8期3152-3167,共16页
The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set inco... The isolated fracture-vug systems controlled by small-scale strike-slip faults within ultra-deep carbonate rocks of the Tarim Basin exhibit significant exploration potential.The study employs a novel training set incorporating innovative fault labels to train a U-Net-structured CNN model,enabling effective identification of small-scale strike-slip faults through seismic data interpretation.Based on the CNN faults,we analyze the distribution patterns of small-scale strike-slip faults.The small-scale strike-slip faults can be categorized into NNW-trending and NE-trending groups with strike lengths ranging 200–5000 m.The development intensity of small-scale strike-slip faults in the Lower Yingshan Member notably exceeds that in the Upper Member.The Lower and Upper Yingshan members are two distinct mechanical layers with contrasting brittleness characteristics,separated by a low-brittleness layer.The superior brittleness of the Lower Yingshan Member enhances the development intensity of small-scale strike-slip faults compared to the upper member,while the low-brittleness layer exerts restrictive effects on vertical fault propagation.Fracture-vug systems formed by interactions of two or more small-scale strike-slip faults demonstrate larger sizes than those controlled by individual faults.All fracture-vug system sizes show positive correlations with the vertical extents of associated small-scale strike-slip faults,particularly intersection and approaching fracture-vug systems exhibit accelerated size increases proportional to the vertical extents. 展开更多
关键词 Small-scale strike-slip faults Convolutional neural network Fault label Isolated fracture-vug system Distribution patterns
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Transport Patterns of Seasonal Suspended Particulate Matter Around the Western Sunda Shelf 被引量:1
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作者 ZHANG Hui LIU Shengfa +9 位作者 WU Kaikai AI Lina CAO Peng BAI Yazhi WANG Xiaojing WANG Hongmin MOHAMED Che Abd Rahim KHOKIATTIWONG Somkiat KORNKANITNAN Narumol SHI Xuefa 《Journal of Ocean University of China》 2025年第6期1561-1574,共14页
The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.T... The transport of suspended particulate matter is a crucial aspect of studies on sediment source-to-sink processes.However,research on its transport patterns in high-erosion areas of low-latitude seas remains limited.To elucidate modern land-sea interaction processes controlled by the monsoon climate,this study investigates the seasonal transport patterns and control mechanisms of suspended particulate matter in the western Sunda Shelf.Results reveal significant seasonal variations in the spatial distribution of suspended particulate matter concentrations,with elevated levels observed during autumn compared with spring.These differences are directly attributed to the East Asian monsoon,including seasonal monsoon precipitation and the associated transport dynamics.During the northeast monsoon,the Malay Peninsula serves as a primary source for the western sea area,with terrestrial materials from its rivers transported to the northern Gulf of Thailand.This transport pattern shifts to an S-shaped,clockwise circulation during upwelling events.Conversely,in the southwest monsoon,rivers in the northern Gulf of Thailand become the predominant sources for the Sunda Shelf,with terrestrial materials carried by clockwise currents toward the eastern Malay Peninsula.When upwelling occurs off the southern Indochina Peninsula,one branch heads toward the South China Sea and the other toward the southern tip of the Malay Peninsula.The seasonal variation in material sources is further supported by the distribution of clay minerals and the discrimination results of rare earth element proxies,including(La/Sm)UCC-(Gd/Yb)UCCand(La/Yb)UCC-(Gd/Yb)UCC,in surface sediments from the Sunda Shelf and surrounding marine areas. 展开更多
关键词 suspended particulate matter sediment source transport pattern monsoon precipitation sedimentary response Sunda Shelf
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Understanding metastatic patterns in gastric cancer: Insights from lymph node distribution and pathology 被引量:1
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作者 Chris B Lamprecht Tyler Kashuv Brandon Lucke-Wold 《World Journal of Gastrointestinal Oncology》 2025年第4期36-41,共6页
Gastric cancer(GC)represents a significant global health burden due to its high morbidity and mortality.Specific behaviors of GC sub-types,distinct dissem-ination patterns,and associated risk-factors remain poorly und... Gastric cancer(GC)represents a significant global health burden due to its high morbidity and mortality.Specific behaviors of GC sub-types,distinct dissem-ination patterns,and associated risk-factors remain poorly understood.This editorial highlights several key prognostic factors,including pathological staging and vascular invasion,that impact GC.It examines a recent study’s investigation of differential metastatic lymph nodes distribution and survival in upper and lower GC sub-types,focusing on histological characterization,pathophysiology,usage of neoadjuvant chemotherapy,and additional predictive determinants.We assess the statistical robustness and clinical applicability of the findings,un-derscoring the importance of treating GC as a heterogeneous disease and em-phasizing how tailored surgical approaches informed by lymph node distribution can optimize tumor detection while minimizing unnecessary interventions.The study’s large cohort,multi-center design,and strict inclusion criteria strengthen its validity in guiding surgical planning and risk-stratification.However,inte-grating genetic and molecular data is critical for refining models and broadening applicability.Additionally,recurrence-metrics and infection-related factors,such as Helicobacter pylori and Epstein-Barr virus,absent in the original study,remain vital for directing future research.By bridging metastatic patterns with pros-pective methodologies and inclusion of diverse populations,this editorial pro-vides a framework for advancing early detection and personalized GC care. 展开更多
关键词 Gastric cancer Lymph node metastasis patterns Upper vs lower gastric cancer Prognostic factors Survival outcomes
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Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study
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作者 Bijnya Birajita Panda Chitaranjan Mishra +3 位作者 Bhagabat Nayak Avik Kumar Roy Logesh Balakrishnan Priyadarshini Mishra 《World Journal of Clinical Cases》 SCIE 2025年第1期29-37,共9页
BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have ... BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no research.AIM To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic intervention.METHODS A cross-sectional survey was disseminated among ophthalmologists all over India.The survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up patterns.RESULTS A total of 180 ophthalmologists responded to the survey.Most practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was advised.The most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid surgeries.Sixty-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease patients.CONCLUSION Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular conditions.Many ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract surgery.Eyelid conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections. 展开更多
关键词 Oculoplasty Ophthalmic plastic surgery Nasolacrimal duct obstruction Practice patterns SURVEY
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Application of Fractal Technology in the Generative Design of Chaoshan Drawnwork Patterns
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作者 CHEN Jia-jun ZHANG Ya CHEN Zhao-yang 《印刷与数字媒体技术研究》 北大核心 2025年第5期179-194,共16页
Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potentia... Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potential of fractals in traditional textile design,a fractal-based generative framework was proposed for efficiently creating drawnwork patterns suitable for practical handicraft production.The research was initiated with an analysis of the structural composition of center,skeleton,and filler motifs extracted from a pattern sample library.Based on this hierarchical classification,the box-counting method was employed to calculate their respective fractal dimensions.Building on fractal art theory,generative algorithms,and studies on the application of Ultra Fractal,a Chaoshan drawnwork fractal design model was established.Using this model,51 drawnwork fractal patterns and 153 handkerchief patterns were generated.These patterns were subsequently applied in real-world production to validate the feasibility and value of fractal techniques in textile design. 展开更多
关键词 Chaoshan drawnwork Fractal pattern Generative design Cultural heritage
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Territorial Ecological Restoration with a High-carbon Storage Focus in the Beibu Gulf Urban Agglomeration of China:Insights from Carbon Metabolism Spatial Security Patterns 被引量:1
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作者 QIN Menglin LIU Yuting +5 位作者 TAN Qianxi ZHU Ziming WU Xinyu JIANG Hongbo LI Hang SHI Qianqian 《Chinese Geographical Science》 2025年第1期73-91,共19页
This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking an... This study focuses on urgent research on restoring and enhancing carbon storage capacity in the Beibu Gulf Urban Agglomer-ation of China,a key area in the‘Belt and Road’Initiative,which aligns with carbon peaking and neutrality goals.This research ana-lyzes the spatial characteristics of carbon metabolism from 2000 to 2020 and uses models to identify stable carbon sink areas,positive carbon flow corridors,and carbon sequestration nodes.The goal is to construct a carbon metabolism spatial security pattern(CMSSP)and propose territorial ecological restoration strategies under different development demand scenarios.The results show the following:1)in 2020,the study area’s carbon sink decreased by 8.29×10^(4) t C/yr compared with that in 2010 and by 10.83×10^(4) t C/yr compared with that in 2000.High-carbon sinks were found mainly in mountainous areas,whereas low-carbon sinks are concentrated in urban con-struction land,rural residential areas,and land margins.2)From 2000 to 2020,the spatial security pattern of carbon metabolism tended to be‘high in the middle of the east and west and low in the gulf.’In 2000,2010,and 2020,16 stable carbon sinks were identified.The carbon energy flow density in Guangxi was greater than that in Guangdong and Hainan,with positive carbon flow corridors located primarily in Guangxi and Guangdong.The number of carbon sequestration nodes remained stable at approximately 15,mainly in Guangxi and Hainan.3)Scenario simulations revealed that under the Nature-based mild restoration scenario,the carbon sink rate will reach 611.85×10^(4) t C/yr by 2030 and increase to 612.45×10^(4) t C/yr by 2060,with stable carbon sinks increasing to 18.In the restora-tion scenario based on Anti-globalization,the carbon sink will decrease from 610.24×10^(4) t C/yr in 2030 to 605.19×10^(4) t C/yr in 2060,with the disappearance of some positive carbon flow corridors and stable carbon sinks.Under the Human-based sustainable restoration scenario,the carbon sink area will decrease from 607.00×10^(4) t C/yr in 2030 to 596.39×10^(4) t C/yr in 2060,with carbon sink areas frag-menting and positive carbon flow corridors becoming less dense.4)On the basis of the current and predicted CMSSPs,this study ex-plores spatial ecological restoration strategies for high-carbon storage areas in bay urban agglomerations at four levels:the land control region,urban agglomeration structure system,carbon sink structure and bay structure control region. 展开更多
关键词 carbon metabolism spatial security pattern(CMSSP) territorial ecological restoration carbon sink carbon storage capacity Beibu Gulf Urban Agglomeration China
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Identification and classification of solid-liquid flow patterns in deviated and horizontal annuli
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作者 Di Yao Xiaofeng Sun Jingyu Qu 《Natural Gas Industry B》 2025年第3期386-404,共19页
During horizontal well drilling,the interaction between drilling fluid and cuttings entering the annulus generates diverse flow patterns.These solid-liquid two-phase flow patterns must be accurately predicted to optim... During horizontal well drilling,the interaction between drilling fluid and cuttings entering the annulus generates diverse flow patterns.These solid-liquid two-phase flow patterns must be accurately predicted to optimize the determination of hydraulic parameters and improve the efficiency of cuttings transport.Accordingly,this study identified flow patterns and conducted transition experiments under different inclination angles using a visualized wellbore annulus apparatus(120 mm outer diameter/73 mm inner diameter).Through direct visual observations,four primary flow patterns were systematically classified on the basis of the solid-liquid two-phase flow behaviors identified in the experiments:stable bed(SB),sand wave(SW),sand dune(SD),and bed load(BL)flows.The experimental data were then used to construct flow pattern maps with solid/liquid phases as axes,after which the transition boundaries between different flow patterns were established.The morphological characteristics and transition mechanisms of SB,SW,SD,and BL flows were systematically analyzed to develop three predictive models of the fluid dynamics principles governing these flow patterns’transitions:(1)A transition boundary model of SB and SW flows was established using Kelvin-Helmholtz stability,for which a stability analysis of solid-liquid two-phase flow in deviated and horizontal annuli was carried out.(2)A transition boundary model of SW and SD flows was constructed through an analysis of the geometric features of sand waves in the annuli,with the critical ratio of the average height of a cuttings bed to its height after erosion being 0.45.(3)A traditional critical velocity model was refined by adjusting the von Karman constant to account for the effect of solid volume concentration,yielding a boundary model for the transition of SW or SD flow into BL flow.All the models were experimentally validated.Finally,we integrated the models to develop a unified method for identifying and classifying the patterns typifying solid-liquid two-phase flow in deviated and horizontal annuli. 展开更多
关键词 Solid-liquid two-phase flow Flow pattern map Flow pattern transformation Cuttings transport Drilling hydraulic
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Application of Chinese Traditional Decorative Patterns on Bronze Ware of Shang Dynasty in the Film & TV Costume Design
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作者 DU Bing-bing WANG Qi-fan 《Journal of Literature and Art Studies》 2025年第2期79-85,共7页
In contemporary China,some domestic films are deeply rooted in traditional Chinese culture,contributing to more and more excellent film&TV programs,among which,the styling inspired by animal patterns on Late Shang... In contemporary China,some domestic films are deeply rooted in traditional Chinese culture,contributing to more and more excellent film&TV programs,among which,the styling inspired by animal patterns on Late Shang Dynasty bronze ware has given strong vitality to the film&TV programs.This paper is intended to compile and understand the cultural value and artistic features of the patterns on Late Shang Dynasty bronze ware as well as its value in the traditional pattern application.It provides certain references regarding the role of film&TV styling in the inheritance and application of traditional patterns,if we analyze the cognition and status quo of the Late Shang Dynasty bronze ware patterns in the contemporary film&TV styling,and if we go deep into its artistic value and its application within such makeup design and identify the problems and laws in current design cases.Such analysis also provides a way of thinking for the application of traditional patterns in current film&TV costume design. 展开更多
关键词 animal patterns on bronze ware of Late Shang Dynasty film&TV styling film&TV costume design traditional patterns
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Patterns dynamics in a diffusive prey-predator system with ratio-dependent functional response in a planar domain
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作者 Xiang-Ping Yan Cun-Hua Zhang 《International Journal of Biomathematics》 2025年第6期139-162,共24页
This paper is concerned with a classical two-species prey-predator reaction-diffusion system with ratio-dependent functional response and subject to homogeneous Neumann boundary condition in a two-dimensional rectangl... This paper is concerned with a classical two-species prey-predator reaction-diffusion system with ratio-dependent functional response and subject to homogeneous Neumann boundary condition in a two-dimensional rectangle domain.By analyzing the associated eigenvalue problem,the spatially homogeneous Hopf bifurcation curve and Turing bifurcation curve of system at the constant coexistence equilibrium are established.Then when the bifurcation parameter is in the interior of range for Turing instability and near Turing bifurcation curve,the amplitude equations of the original system near the constant coexistence equilibrium are obtained by multiple-scale time perturbation analysis.On the basis of the obtained amplitude equations,the stability and classifications of spatiotemporal patterns of the original system at the constant coexistence equilibrium are discussed.Finally,to verify the validity of the obtained theoretical results,numerical simulations are also carried out. 展开更多
关键词 Prey-predator reaction-diffusion system amplitude equations Turing pattern
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Environmental Features of Heavy Precipitation under Favorable Synoptic Patterns:A Lesson from the 2021 Henan Extreme Precipitation Event
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作者 Nan LV Zhongxi LIN +2 位作者 Ji NIE Zhiyong MENG Ping LU 《Advances in Atmospheric Sciences》 2025年第9期1863-1875,共13页
In July 2021,a catastrophic extreme precipitation(EP)event occurred in Henan Province,China,resulting in considerable human and economic losses.The synoptic pattern during this event is distinctive,characterized by th... In July 2021,a catastrophic extreme precipitation(EP)event occurred in Henan Province,China,resulting in considerable human and economic losses.The synoptic pattern during this event is distinctive,characterized by the presence of two typhoons and substantial water transport into Henan.However,a favorable synoptic pattern only does not guarantee the occurrence of heavy precipitation in Henan.This study investigates the key environmental features critical for EP under similar synoptic patterns to the 2021 Henan extreme event.It is found that cold clouds are better aggregated on EP days,accompanied by beneficial environment features like enhanced moisture conditions,stronger updrafts,and greater atmospheric instability.The temporal evolution of these environmental features shows a leading signal by one to three days.These results suggest the importance of combining the synoptic pattern and environmental features in the forecasting of heavy precipitation events. 展开更多
关键词 extreme precipitation synoptic pattern environmental features
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VECTOR ROGUE WAVE PATTERNS OF THE MULTI-COMPONENT NONLINEAR SCHR?DINGER EQUATION AND GENERALIZED MIXED ADLER-MOSER POLYNOMIALS
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作者 Huian LIN Liming LING 《Acta Mathematica Scientia》 2025年第6期2478-2509,共32页
This paper investigates the asymptotic behavior of high-order vector rogue wave(RW)solutions for any multi-component nonlinear Schr¨odinger equation(denoted as n-NLSE)with multiple internal large parameters.We re... This paper investigates the asymptotic behavior of high-order vector rogue wave(RW)solutions for any multi-component nonlinear Schr¨odinger equation(denoted as n-NLSE)with multiple internal large parameters.We report some novel RW patterns,including nonmultiple root(NMR)-type patterns with distinct shapes such as semicircular sector,acute sector,pseudo-hexagram,and pseudo-rhombus shapes,as well as multiple root(MR)-type patterns characterized by right double-arrow and right arrow shapes.We demonstrate that these RW patterns are intrinsically related to the root structures of a novel class of polynomials,termed generalized mixed Adler-Moser(GMAM)polynomials,which feature multiple arbitrary free parameters.The RW patterns can be interpreted as straightforward expansions and slight shifts of the root structures for the GMAM polynomials to some extent.In the(x,t)-plane,they asymptotically converge to a first-order RW at the location corresponding to each simple root of the polynomials and to a lower-order RW at the location associated with each multiple root.Notably,the position of the lower-order RW within these patterns can be flexibly adjusted to any desired location in the(x,t)-plane by tuning the free parameters of the corresponding GMAM polynomials. 展开更多
关键词 n-NLSE RW pattern ASYMPTOTICS GMAM polynomial root structure
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Patterns of plant species richness and diversity across treelines in Himachal Pradesh,Western Himalaya
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作者 Rohit SHARMA Sanjay Kr.UNIYAL Shalinder KAUR 《Journal of Mountain Science》 2025年第5期1586-1599,共14页
Treelines are ecologically unique,fragile,and rich in natural resources.They harbour high species diversity and at the same time are under threat due to anthropogenic activities.Recognizing this,the present study has ... Treelines are ecologically unique,fragile,and rich in natural resources.They harbour high species diversity and at the same time are under threat due to anthropogenic activities.Recognizing this,the present study has been framed to document the patterns of species richness and diversity in the state of Himachal Pradesh,western Himalaya.A total of six treeline sites(three disturbed and three undisturbed)were identified for vegetation sampling.Trees,shrubs,and herbs were sampled at each site using nested plots of 10 m^(2),5 m^(2),and 1 m^(2),respectively.The study exhibits the rich diversity of treeline communities,the patterns of which varied between treeline sites.Altogether,221 species of vascular plants belonging to 47 families and 140 genera were recorded from the area.Amongst families,Asteraceae was the dominant family followed by Apiaceae and Ranunculaceae.The study also revealed the presence of threatened species like Aconitum heterophyllum,Angelica glauca,Bergenia stracheyi,Dactylorhiza hatagirea,Picrorhiza kurroa,and Trillium govanianum etc.at treeline.Moreover,species composition revealed high densities of Betula utilis followed by the under canopy of Rhododendron campanulatum and R.anthopogon at treeline sites.Overall,species richness of herbs,shrubs,and trees were higher at undisturbed site as compared to disturbed one.The diversity indices of herbs and shrubs varied significantly between treeline sites while that of trees was non-significant.At the same time,soil properties showed distinct patterns wherein pH and available nitrogen significantly varied between treeline sites.Present study provides detailed insights into the floristic and ecological aspects of treeline communities from the unexplored ecoregion of western Himalaya.The treelines in the area are anthropogenically depressed and continued land-use activities might result in habitat fragmentation and displacement of plant communities in the near future. 展开更多
关键词 Alpine treeline DISTURBANCE Floristic diversity HIMALAYA Soil Vegetation patterns
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Motion Patterns and Kinematic Modeling of Backswimmer Hind Legs
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作者 Shulong Fan Cunzhi Hu +1 位作者 Fuchun Yang Yiheng Fu 《Journal of Bionic Engineering》 2025年第6期2936-2949,共14页
Backswimmers exhibit a high degree of mobility in water,and their different motion patterns have important implications for the design of micro-biomimetic underwater robots.This paper used three-dimensional high-speed... Backswimmers exhibit a high degree of mobility in water,and their different motion patterns have important implications for the design of micro-biomimetic underwater robots.This paper used three-dimensional high-speed cameras to extract the key points on the hind legs.The hind leg motion laws and the deformation laws of the setae were obtained in four motion patterns:rapid forward,cruising,in-motion turning,and in-place turning.The motion laws of each joint on the hind leg are modeled using a Fourier series.A kinematic model of hind legs was established based on the DH method,and the motion characteristics of hind legs under different motion patterns were analyzed.This paper provides basic data and theoretical models for micro-biomimetic robots. 展开更多
关键词 Backswimmer Hind leg SETAE Motion pattern Kinematic model
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