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Impact Analysis of Microscopic Defect Types on the Macroscopic Crack Propagation in Sintered Silver Nanoparticles
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作者 Zhongqing Zhang Bo Wan +4 位作者 Guicui Fu Yutai Su Zhaoxi Wu Xiangfen Wang Xu Long 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期441-458,共18页
Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,t... Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs. 展开更多
关键词 Sintered silver nanoparticles defect types microscopic defect evolution macroscopic crack propagation molecular dynamics simulation cohesive zone model
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Effect of special types of bread with select herbal components on postprandial glucose levels in diabetic patients
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作者 Drasko M Gostiljac Srdjan S Popovic +4 位作者 Vesna Dimitrijevic-Sreckovic Sasa M Ilic Jelena A Jevtovic Dragan M Nikolic Ivan A Soldatovic 《World Journal of Diabetes》 SCIE 2024年第4期664-674,共11页
BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(T2DM)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food ... BACKGROUND Nutrition recommendations in patients with type 2 diabetes mellitus(T2DM)are to consume rye or integral bread instead of white bread.A positive effect on glucoregulation has been achieved by enriching food with various biologically active substances of herbal origin,so we formulated an herbal mixture that can be used as a supplement for a special type of bread(STB)to achieve better effects on postprandial glucose and insulin levels in patients with T2DM.AIM To compare organoleptic characteristics and effects of two types of bread on postprandial glucose and insulin levels in T2DM patients.METHODS This trial included 97 patients with T2DM.A parallel group of 16 healthy subjects was also investigated.All participants were given 50 g of rye bread and the same amount of a STB with an herbal mixture on 2 consecutive days.Postprandial blood glucose and insulin levels were compared at the 30^(th),60^(th),90^(th) and 120th min.A questionnaire was used for subjective estimation of the organoleptic and satiety features of the two types of bread.RESULTS Compared to patients who consumed rye bread,significantly lower postprandial blood glucose and insulin concentrations were found in T2DM patients who consumed STB.No relevant differences were found among the healthy subjects.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.CONCLUSION STB have better effects than rye bread on postprandial glucoregulation in T2DM patients.Subjectively estimated organoleptic and satiety characteristics are better for STB than for rye bread.Therefore,STB can be recommended for nutrition in T2DM patients. 展开更多
关键词 Special types of bread Postprandial glucoregulation INSULIN NUTRITION Type 2 diabetes mellitus
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Differential Expression of Genes Related to Fruit Development and Capsaicinoids Synthesis in Habanero Pepper Plants Grown in Contrasting Soil Types
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作者 Eduardo Burgos-Valencia Federico García-Laynes +4 位作者 Ileana Echevarría-Machado Fatima Medina-Lara Miriam Monforte-González JoséNarváez-Zapata Manuel Martínez-Estévez 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期151-183,共33页
Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives the... Habanero pepper(Capsicum chinense Jacq.)is a crop of economic relevance in the Peninsula of Yucatan.Its fruits have a high level of capsaicinoids compared to peppers grown in other regions of the world,which gives them industrial importance.Soil is an important factor that affects pepper development,nutritional quality,and capsaicinoid content.However,the effect of soil type on fruit development and capsaicinoid metabolism has been little understood.This work aimed to compare the effect of soils with contrasting characteristics,black soil(BS)and red soil(RS),on the expression of genes related to the development of fruits,and capsaicinoid synthesis using a transcriptomic analysis of the habanero pepper fruits.Plants growing in RS had bigger fruits and higher expression of genes related to floral development,fruit abscission,and softening which suggests that RS stimulates fruit development from early stages until maturation stages.Fruits from plants growing in BS had enrichment in metabolic pathways related to growth,sugars,and photosynthesis.Besides,these fruits had higher capsaicinoid accumulation at 25 days post-anthesis,and higher expression of genes related to the branched-chain amino acids metabolism(ketol-acid reductisomerase KARI),pentose phosphate pathway and production of NADPH(glucose-6-phosphate-1-dehydrogenase G6PDH),and proteasome and vesicular traffic in cells(26S proteasome regulatory subunit T4 RPT4),which suggest that BS is better in the early stimulation of pathways related to the nutritional quality and capsaicinoid metabolism in the fruits. 展开更多
关键词 Capsicum chinense jacq soil types plant growth environmental conditions fruit quality capsaicinoid metabolism TRANSCRIPTOME
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Principles for Designing New Types of Housing for a Strong and Resilient Local Economy in the Republic of Congo
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作者 Alain Symphorien Ndongo Destin Gemetone Etou Christian Tathy 《Open Journal of Civil Engineering》 2024年第1期82-95,共14页
The Congolese population is organised into households, which are thus headed by a chief who ensures the social well-being, development and integration into working life of the individuals in his charge. This study exa... The Congolese population is organised into households, which are thus headed by a chief who ensures the social well-being, development and integration into working life of the individuals in his charge. This study examines the functional principles of new housing design as an instrument for transforming the (current) failing economy into a strong and resilient one. Accordingly, a literature review of the practice of designing and building housing in human settlements in the Congo revealed the state of the art on this subject. An analysis of the existing housing stock from a demographic, social and economic point of view made it possible to identify the most common household sizes and numbers, as well as the lifestyle processes that determine the need for developed space. To this end, the experimental method was used to propose configuration plans for various new types of dwelling. To this end, the study highlighted the link between people’s standard of living and the effectiveness of their involvement in the local economy. To achieve the aims of the National Development Plan (NDP), particular attention must be paid to solving the housing problem. The existing housing stock actively contributes to the problems associated with unemployment and insecurity. Functional principles for the design of new types of housing have been developed. Four model types are proposed in line with the demographic structure of the population, their socio-economic characteristics and their lifestyle. 展开更多
关键词 Congolese Households New types of Lodging Human Settlements Resilient Local Economy Households Resilient Endogenous Economy Logement CONCEPTION
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The Spatiotemporal Distribution Characteristics of Cloud Types and Phases in the Arctic Based on CloudSat and CALIPSO Cloud Classification Products
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作者 Yue SUN Huiling YANG +5 位作者 Hui XIAO Liang FENG Wei CHENG Libo ZHOU Weixi SHU Jingzhe SUN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期310-324,共15页
The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud typ... The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds. 展开更多
关键词 CloudSat and CALIPSO cloud type cloud phase temporal and spatial distribution interannual variation
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Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China
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作者 Ya-ying Wang Ling-sen Zeng +6 位作者 Li-e Gao Li-long Yan Ling-hao Zhao Jia-hao Gao Ying-long Di Guang-xu Li Yi-hong Tian 《China Geology》 CAS CSCD 2024年第1期80-90,共11页
Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast Tibet.They are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.... Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast Tibet.They are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation time.Taking all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be summarized.The“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(LIP),suggesting that they represent melts directly generated from the Kerguelen mantle plume.The“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative anomalies.They show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle source.Considering their closely spatial and temporal relationship with the widespread Comei LIP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different proportions.These weak enriched mafic rocks in Comei LIP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere interaction.This process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous. 展开更多
关键词 OIB type diabase Comei Large Igneous Province Weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume Geological survey engineering Tibet Plateau
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Soil Organic Carbon Stock Variation under Different Soil Types and Land Uses in the Sub-Humid Noun Plain, Western Cameroon
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作者 Frank Abigail Sobze Kenfack Georges Kogge Kome +2 位作者 Achille Bienvenue Ibrahim Viviane Pauline Mandah Dieudonne Bitondo 《Open Journal of Soil Science》 2024年第4期191-209,共19页
This study was conducted to assess the current stock of soil organic carbon under different agricultural land uses, soil types and soil depths in the Noun plain in western Cameroon. Three sites were selected for the s... This study was conducted to assess the current stock of soil organic carbon under different agricultural land uses, soil types and soil depths in the Noun plain in western Cameroon. Three sites were selected for the study, namely Mangoum, Makeka and Fossang, representative of the three dominant soil types of the noun plain (Andosols, Acrisols and Ferralsols). Three land uses were selected per site including natural vegetation, agroforest and crop field. Soil was sampled at three depths;0 - 20 cm, 20 - 40 cm, and 40 - 60 cm. Analysis of variance showed that soil type did not significantly influence carbon storage, but rather land uses and soil depth. SOCS decreased significantly with depth in all the sites, with an average stock of 66.3 ± 15.8 tC/ha at 0 - 20 cm, compared to an average stock of 33.3 ± 7.4 tC/ha at 40 - 60 cm. SOCS was significantly highest in the natural formation with 57.2 ± 19.7 tC/ha, and lowest in cultivated fields, at 37.7 ± 10.6 tC/ha. Andosols, with their high content of coarse fragments, stored less organic carbon than Ferralsols and Acrisols. 展开更多
关键词 Carbon Stocks Soil Type Soil Depth Agricultural Land Use Noun Plain
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Mechanical Properties of Self-Compacting Rubberized Concrete with Different Rubber Types under Triaxial Compression
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作者 Chunli Meng Weishu Fu +2 位作者 Jianzeng Shen Yisheng Su Chunying Ye 《Journal of Renewable Materials》 SCIE EI 2023年第2期581-598,共18页
Different rubber aggregates lead to changes in the effect of stress conditions on the mechanical behavior of concrete,and studies on the triaxial properties of self-compacting rubber concrete(SCRC)are rare.In this stu... Different rubber aggregates lead to changes in the effect of stress conditions on the mechanical behavior of concrete,and studies on the triaxial properties of self-compacting rubber concrete(SCRC)are rare.In this study,35 cylindrical specimens taking lateral stress and rubber type as variables were prepared to study the fresh properties and mechanical behaviors of SCRC under triaxial compression,where the rubber contains two types,i.e.,380μm rubber powder and 1–4 mm rubber particles,and four contents,i.e.,10%,20%and 30%.The test results demonstrated that SCRC exhibited a typical oblique shear failure mode under triaxial compression and had a more moderate descending branch compared with self-compacting concrete(SCC).The presence of lateral stress can significantly improve the compression properties,including initial elastic modulus,peak stress and peak strain,with an improvement range of 3%–73%for peak stress.While rubber aggregates mainly targeted the deformation abilities and toughness for improvement,and the peak strain improvement ranges were 0.1–3.1 times and 0.1–1.0 times for SCRC containing rubber powder and SCRC containing rubber particles,respectively,relative to SCC.At a high lateral stress of at least 12 MPa,the loss of strength due to the addition of rubber can be controlled within 10%,in which case the content of rubber powder and rubber particles was recommended to be at most 20%and 30%,respectively.Based on the Mohr-Coulomb theory,the failure criteria of SCRC with different rubber types were established.For analysis and design purposes,an empirical model was proposed to predict the stressstrain behavior under triaxial compression,considering the influence of different rubber content and lateral stress.The results obtained in this study can provide a valuable reference for the design and application of self-compacting rubberized concrete in practical projects,especially those involving three-way compression states and requiring high-quality deformation and energy dissipation. 展开更多
关键词 Self-compacting rubberized concrete rubber types triaxial mechanical properties failure criterion constitutive model
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Correlation between the Distribution of Traditional Chinese Medicine Syndromes and Molecular Types of Breast Cancer in Perichemotherapy Period
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作者 Bingxin Meng Xufeng Cheng +3 位作者 Qi Liu Huiduo Zhao Beibei Wang Liuyan Xu 《Chinese Medicine and Natural Products》 CAS 2023年第4期183-190,共8页
Objectives The objective of this study was to explore the correlation between the distribution of traditional Chinese medicine(TCM)syndromes and molecular types of breast cancer in the perichemotherapy period.Methods ... Objectives The objective of this study was to explore the correlation between the distribution of traditional Chinese medicine(TCM)syndromes and molecular types of breast cancer in the perichemotherapy period.Methods A total of 325 cases with perichemotherapy breast cancer was classified according to syndrome differentiation in TCM,and R×C table x2 test was used to examine and analyze the relationship between TCM syndromes and molecular types of breast cancer in the perichemotherapy period.Results(1)In the early stage of chemotherapy,there was no significant difference in the distribution of different TCM syndromes among molecular types,mainly liver depression syndrome and liver depression and phlegm coagulation syndrome(p>0.05).(2)In the middle stage of chemotherapy,there were significant differences in the distribution of spleen deficiency and phlegm-dampness syndrome among HER-2 positive(HR positive),HER-2 positive(HR negative),and Luminal Atype,Luminal B type(HER-2 negative),and triple-negative type(p<0.01).(3)After chemotherapy,there were significant differences in the distribution of spleen and kidney yang deficiency syndrome and marrow sea insufficiency syndrome among HER-2 positive(HR negative),triple-negative type,and HER-2 positive(HR positive),Luminal A type,Luminal B type(HER-2 negative),and triple-negative type(p<0.01).Conclusion(1)In the middle stage of chemotherapy,HER-2 positive(HR positive)and HER-2 positive(HR negative)are more likely to show spleen deficiency and phlegmdampness syndrome than other molecular types.(2)In the late stage of chemotherapy,the HER-2 positive(HR negative)and triple-negative type is more likely to show spleenkidney yang deficiency syndrome than other molecular types,and the triple-negative type is more likely to show marrow sea insufficiency syndrome than other molecular types. 展开更多
关键词 breast cancer perichemotherapy TCM syndromes molecular types
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The Relationship between Golgi Protein 73, Alpha-Fetoprotein, Liver Function Indicators, and Traditional Chinese Medicine Syndrome Types of Primary Liver Cancer
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作者 Baoping Lu Jinxia Rong Huaimin Liu 《Chinese Medicine and Natural Products》 CAS 2023年第4期165-171,共7页
Objective Our objective was to analyze the correlation between Golgi protein 73(GP73),alpha-fetoprotein(AFP),liver function indicators,and traditional Chinese medicine(TCM)syndrome types of primary liver cancer(herein... Objective Our objective was to analyze the correlation between Golgi protein 73(GP73),alpha-fetoprotein(AFP),liver function indicators,and traditional Chinese medicine(TCM)syndrome types of primary liver cancer(hereinafter referred to as"liver cancer").Methods In total,156 liver cancer patients(liver cancer group)and 52 healthy individuals(health group)were selected as the research subjects to detect their GP73,AFP expression,and liver function-related indicators.The obtained data were statistically analyzed using SPSS 21.0 software.Results(1)The positive expression rate of GP73 in the liver cancer group was 50%;the positive expression rates of qi stagnation and blood stasis syndrome,heat tgxin in liver and galader yndroeand yndefceny flieran kidney yndg1i,%54.3,and 59.6%,respectively.There was no statistically significant difference betwgep the groups(p>0.05),The positive expreion rate of AFP was 50%.he positiy 32.8 expression rates of qi stagnation and blood stasis syndrome,heat-toxin in liyer ane gallbladder syndrome,and yin deficiency of liver and kidney syndrome were 41.7,54.3 an59.6%,respectively.There was a statistically significant difference between the groups(p<0.05).(2)The GP73 levels of patients with different syndrome types in the liver cancer group were ranked from high to low as yin deficiency of liver and ki41.3 syndrome,heat toxin in liver and gallbladder syndrome,and qi stagnation and brooa stasis syndrome.The differences between the groups were statistically significant(p<0.05).The AFP levels of patients with different syndrome types in the liver cancer group were ranked from high to low as heat toxin in liver and gallbladder syndrome,yin deficiency of liver and kidney syndrome,and qi stagnation and blood stasis syndrome.There was no statistically significant difference between the groups(p>0.05).(3)Analysis of liver function indicators in the liver cancer group:the alanine transaminase s(ALT)levels of patients with different syndrome types were in descending order from high to low,including yin deficiency of liver and kidney syndrome,heat toxin in liver and gallbladder syndrome,and qi stagnation and blood stasis syndrome.The differences between groups were statistically significant(p<0.05).The aspartate aminotransferase(AST)levels of patients with different syndrome types were ranked from high to low as follows:heat toxin in liver and gallbladder syndrome,yin deficiency of liver and kidney syndrome,and qi stagnation and blood stasis syndrome.The difference between groups was statistically significant(p<0.05).The levels of albumin(ALB)in patients with different syndrome types were ranked from high to low,including heat toxin in liver and gallbladder syndrome,qi stagnation and blood stasis syndrome,and yin deficiency of liver and kidney syndrome.The differences between groups were statistically significant(p<0.05).Conclusion GP73 and indicators such as ALT,AST,and ALB are of great significance in the diagnosis of TCM syndrome differentiation and classification of liver cancer patients. 展开更多
关键词 primary liver cancer Golgi protein 73 ALPHA-FETOPROTEIN liverfunction TCM syndrome types
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Correlation Analysis of Traditional Chinese Medicine Syndrome Types and Influencing Factors of Asthmatic Bronchitis in Children
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作者 Miao Ren Shijie Luo 《Proceedings of Anticancer Research》 2023年第3期7-12,共6页
Objective:To explore the correlation between traditional Chinese medicine(TCM)syndrome types and the influencing factors of asthmatic bronchitis in children,as well as to provide clinical syndrome differentiation basi... Objective:To explore the correlation between traditional Chinese medicine(TCM)syndrome types and the influencing factors of asthmatic bronchitis in children,as well as to provide clinical syndrome differentiation basis and reference for the treatment of children with asthmatic bronchitis.Methods:The clinical data of 197 inpatients with asthmatic bronchitis in our hospital from March 2021 to March 2022 were collected,referring to“Zhu Futang Practical Pediatrics”(7th Edition,2002)and“Chinese Medicine Industry Standards-Standards for Diagnosis and Efficacy of Pediatric Diseases and Syndromes of Traditional Chinese Medicine”(1994,State Administration of Traditional Chinese Medicine)for diagnosis,classification,and analysis of TCM syndrome types and the influencing factors of asthmatic bronchitis in children.Results:(i)cold asthma syndrome contributed to the majority of TCM syndrome types of pediatric asthmatic bronchitis;(ii)gender had a great influence on TCM syndromes types in children with asthmatic bronchitis,and the differences among the TCM syndrome types were statistically significant(P<0.05);(iii)there was no significant difference in the distribution of TCM syndrome types of pediatric asthmatic bronchitis among different age groups(P>0.05);(iv)birth status had no effect on the distribution of TCM syndrome types of pediatric asthmatic bronchitis(P>0.05);(v)no significant correlation was observed between the mode of delivery and the distribution of TCM syndrome types in children with asthmatic bronchitis(P>0.05);(vi)children with cold asthma syndrome,heat asthma syndrome,and mixed cold and heat syndrome were not breastfed,and there was no significant difference in the feeding methods of children with mixed deficiency and excess syndrome(P>0.05);(vii)no significant correlation was observed between the TCM syndrome types of pediatric asthmatic bronchitis and family history of asthma/allergy(P>0.05);(viii)a significant correlation was observed between different TCM syndrome types and history of drug and food allergy(P<0.05);(ix)normal or high eosinophil percentage was commonly observed in children with asthmatic bronchitis,and there was no significant difference among the different TCM syndrome types(P>0.05).Conclusion:The TCM syndrome types of pediatric asthmatic bronchitis are related to gender,feeding history,allergy history,and other factors,which may be influencing factors of the TCM syndrome types of pediatric asthmatic bronchitis. 展开更多
关键词 Asthmatic bronchitis CHILDREN TCM syndrome types Influencing factors
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Sub-stand diameter distribution types vary along an old-growth Douglas-fir chronosequence into the horizontal diversification development stage 被引量:1
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作者 JeriLynn E.Peck Eric K.Zenner 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期415-424,共10页
Managing mature Douglas-fir[Pseudotsuga menziesii(Mirb.)Franco]stands to emulate the structural complexity of natural old-growth forest requires identifying structural targets at the sub-stand level at which neighborh... Managing mature Douglas-fir[Pseudotsuga menziesii(Mirb.)Franco]stands to emulate the structural complexity of natural old-growth forest requires identifying structural targets at the sub-stand level at which neighborhood dynamics and patchy disturbance shape structure.We therefore sought to describe the archetypal shapes of predominant sub-stand diameter distribution types(DDTs)observed in natural tree neighborhoods in stands comprising a chronosequence(ca.120-450+yrs)encompassing mature,vertical diversification,and horizontal diversification development stages.The ten 1.0 ha stands are located in the southcentral Oregon Cascades,USA.Building on the known spatial position of each tree,natural tree neighborhoods were identified using the floating neighborhood approach based on spatial tessellation connecting neighboring trees at the first-(mean 61 m2)through fifth-(mean 2058 m2)order scales.Cluster analysis was then used to objectively identify the most predominant DDTs among the relative tree size distributions observed in the trans-scale neighborhoods within each stand.Repeated measures regression was used to classify each DDT to one of six observed archetypal shapes:negative exponential,unimodal,rotated sigmoid,bimodal,concave,or multi-modal.Only three of the 81 observed DDTs deviated by<10%from the stand average,while every stand had at least one DDT that deviated by>50%(maximum 83%).Within each stand,five to ten predominant DDTs were observed,which deviated from the stand average by 30-48%and were characterized by two to five different archetypal shapes.Consequently,in some stands the majority of tree neighborhoods were best characterized by a different shape from that assigned at the stand level.Deviation from the stand average increased from the youngest stand in the mature development stage through the middle stands in the vertical diversification stage to the oldest stands in the horizontal diversification stage.The complexity of DDT shapes tended to increase along the chronosequence(from negative exponential and uniform toward concave and multi-modal),with shape richness highest mid-sequence and evenness peaking in the oldest stands.The high diversity of sub-stand structural complexity reduces the utility of standlevel diameter distributions as old-growth restoration targets.However,the presence in early-sequence stands of sub-stand diameter distributions common to later-sequence stands may facilitate active management at the neighborhood level to promote future old-growth condition.Restoration of substand diameter structures would likely require combining spatial perspectives,such as by augmenting tree-level croptree management with diameter distribution targets for the resulting tree neighborhoods. 展开更多
关键词 Diameter distribution type Floating neighborhood Restoration silviculture SMALL-SCALE Structural complexity
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Uncertainties of landslide susceptibility prediction considering different landslide types 被引量:1
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作者 Faming Huang Haowen Xiong +3 位作者 Chi Yao Filippo Catani Chuangbing Zhou Jinsong Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第11期2954-2972,共19页
Most literature related to landslide susceptibility prediction only considers a single type of landslide,such as colluvial landslide,rock fall or debris flow,rather than different landslide types,which greatly affects... Most literature related to landslide susceptibility prediction only considers a single type of landslide,such as colluvial landslide,rock fall or debris flow,rather than different landslide types,which greatly affects susceptibility prediction performance.To construct efficient susceptibility prediction considering different landslide types,Huichang County in China is taken as example.Firstly,105 rock falls,350 colluvial landslides and 11 related environmental factors are identified.Then four machine learning models,namely logistic regression,multi-layer perception,support vector machine and C5.0 decision tree are applied for susceptibility modeling of rock fall and colluvial landslide.Thirdly,three different landslide susceptibility prediction(LSP)models considering landslide types based on C5.0 decision tree with excellent performance are constructed to generate final landslide susceptibility:(i)united method,which combines all landslide types directly;(ii)probability statistical method,which couples analyses of susceptibility indices under different landslide types based on probability formula;and(iii)maximum comparison method,which selects the maximum susceptibility index through comparing the predicted susceptibility indices under different types of landslides.Finally,uncertainties of landslide susceptibility are assessed by prediction accuracy,mean value and standard deviation.It is concluded that LSP results of the three coupled models considering landslide types basically conform to the spatial occurrence patterns of landslides in Huichang County.The united method has the best susceptibility prediction performance,followed by the probability method and maximum susceptibility method.More cases are needed to verify this result in-depth.LSP considering different landslide types is superior to that taking only a single type of landslide into account. 展开更多
关键词 Landslide susceptibility Landslide type Rock fall Colluvial landslides Machine learning models
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Influence of Surface Types on the Seasonality and Inter-Model Spread of Arctic Amplification in CMIP6 被引量:1
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作者 Yanchi LIU Yunqi KONG +1 位作者 Qinghua YANG Xiaoming HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第12期2288-2301,共14页
A robust phenomenon termed the Arctic Amplification(AA)refers to the stronger warming taking place over the Arctic compared to the global mean.The AA can be confirmed through observations and reproduced in climate mod... A robust phenomenon termed the Arctic Amplification(AA)refers to the stronger warming taking place over the Arctic compared to the global mean.The AA can be confirmed through observations and reproduced in climate model simulations and shows significant seasonality and inter-model spread.This study focuses on the influence of surface type on the seasonality of AA and its inter-model spread by dividing the Arctic region into four surface types:ice-covered,ice-retreat,ice-free,and land.The magnitude and inter-model spread of Arctic surface warming are calculated from the difference between the abrupt-4×CO_(2)and pre-industrial experiments of 17 CMIP6 models.The change of effective thermal inertia(ETI)in response to the quadrupling of CO_(2) forcing is the leading mechanism for the seasonal energy transfer mechanism,which acts to store heat temporarily in summer and then release it in winter.The ETI change is strongest over the ice-retreat region,which is also responsible for the strongest AA among the four surface types.The lack of ETI change explains the nearly uniform warming pattern across seasons over the ice-free(ocean)region.Compared to other regions,the ice-covered region shows the maximum inter-model spread in JFM,resulting from a stronger inter-model spread in the oceanic heat storage term.However,the weaker upward surface turbulent sensible and latent heat fluxes tend to suppress the inter-model spread.The relatively small inter-model spread during summer is caused by the cancellation of the inter-model spread in ice-albedo feedback with that in the oceanic heat storage term. 展开更多
关键词 Arctic amplification surface type dependence seasonal energy transfer effective thermal inertia
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Local and range-wide distribution of song types suggest Ovenbirds(Seiurus aurocapilla)have song neighborhoods but not macro-dialects
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作者 Patrick M.Jagielski Jennifer R.Foote 《Avian Research》 SCIE CSCD 2023年第2期191-199,共9页
The song systems of oscine passerines(songbirds)are complex and diverse.Because songs are used for both mate attraction and territory defense and are therefore important signals for survival and reproduction,comprehen... The song systems of oscine passerines(songbirds)are complex and diverse.Because songs are used for both mate attraction and territory defense and are therefore important signals for survival and reproduction,comprehensive knowledge of within and among species song structure and distribution is informative for understanding the evolution of song repertoires and vocal behaviour.In this study,we explored variation in the song structure of the Ovenbird(Seiurus aurocapilla),a widespread warbler(Family Parulidae)found in North American forests.We analyzed recordings from the 2021 breeding season to assess song type variation at a local(n=158 birds;Sault Ste.Marie,ON)and breeding range scale(n=512 birds;eBird).We characterized the local song types and tested whether Ovenbirds share song types with their neighbors more often than expected by chance.We then characterized song types of Ovenbirds across the breeding range to determine whether any geographic pattern of song clustering exists(i.e.,macro-dialects).We found 10 distinct song types and some evidence for song type clustering at the local study site(i.e.,song neighborhoods).We found 7 of those 10 song types throughout the breeding range and identified an additional 24 types that were not recorded in our local population.We found no evidence for song dialects across the Ovenbird breeding range.This study contributes to our understanding of Ovenbird song while simultaneously adding to our understanding of geographic structuring of warbler repertoires.Our work contributes to delineating a more comprehensive understanding of factors affecting dialect development for this diverse group of songbirds. 展开更多
关键词 DIALECTS eBird Geographic variation Ovenbird Parulidae Seiurus aurocapilla Song type
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Master crack types and typical acoustic emission characteristics during rock failure
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作者 Tongbin Zhao Pengfei Zhang +3 位作者 Yaxun Xiao Weiyao Guo Yulong Zhang Xiufeng Zhang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第1期73-86,共14页
Acoustic emission(AE)signals contain substantial information about the internal fracture characteristics of rocks and are useful for revealing the laws governing the release of energy stored therein.Reported here is t... Acoustic emission(AE)signals contain substantial information about the internal fracture characteristics of rocks and are useful for revealing the laws governing the release of energy stored therein.Reported here is the evolution of rock failure with diferent master crack types as investigated using Brazilian splitting tests(BSTs),direct shear tests(DSTs),and uniaxial compression tests(UCTs).The AE parameters and typical modes of each fracture type were obtained,and the energy release characteristics of each fracture mechanism were discussed.From the observed changes in the AE parameters,the rock fracture process exhibits characteristics of staged intensifcation.The scale and energy level of crack activity in the BSTs were signifcantly lower than those in the DSTs and UCTs.The proportion of tensile cracks in the BSTs was 65%–75%,while the proportions of shear cracks in the DSTs and UCTs were 75%–85%and 70%–75%,respectively.During the rock loading process under diferent conditions,failure was accompanied by an increased number of shear cracks.The amplitude,duration,and rise time of the AE signal from rock failure were larger when the failure was dominated by shear cracks rather than tensile ones,and most of the medium-and high-energy signals had medium to low frequencies.After calculating the proposed energy amplitude ratio,the energy release of shear cracks was found to exceed that of tensile cracks at the same fracture scale. 展开更多
关键词 Rock failure Fracture mechanism Acoustic emission Master crack type Energy release
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Types and Optimization Paths Between Poverty Alleviation Effectiveness and Rural Revitalization:A Case Study of Hunan Province,China
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作者 TAN Xuelan WANG Zhenkai +1 位作者 AN Yue WANG Weilin 《Chinese Geographical Science》 SCIE CSCD 2023年第5期966-982,共17页
Exploring the synergy types and optimization paths between Poverty Alleviation Effectiveness and Rural Revitalization is necessary for achieving the two centenary goals.Taking poverty alleviation counties in Hunan Pro... Exploring the synergy types and optimization paths between Poverty Alleviation Effectiveness and Rural Revitalization is necessary for achieving the two centenary goals.Taking poverty alleviation counties in Hunan Province,China as an example,our study proposed an indicator to measure the synergistic development between Poverty Alleviation Effectiveness and Rural Revitalization using the multi-index integrated evaluation method.Then,the coupling types were classified based on both the proposed indicator and regional characteristics.Besides,the corresponding optimization path for each coupling type was proposed to promote the synergistic development of Poverty Alleviation and Rural Revitalization.Results are as follows:1)Lower synergy focused on the southwestern Hunan,while low synergy is widely distributed(such as the west,southwest,northwest,and midland).Moderate synergy is in the midland,such as Huaihua and Chenzhou cities.High synergy is distributed in Yongzhou,Huaihua,Xiangxi cities,etc.Besides,only Hecheng City belongs to the higher synergy.2)This paper proposes corresponding development paths for different development characteristics and main problems from multiple perspectives of the protection system,industrial planning,and rural market.Continuously consolidate and enhance the effectiveness of Poverty Alleviation and Rural Revitalization to achieve coupled and synergistic development of the two systems.Our research results can provide theoretical support for implementing Poverty Alleviation and Rural Revitalization in Hunan Province,China. 展开更多
关键词 Poverty Alleviation Effectiveness Rural Revitalization coupling synergy type classification optimization path
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Evaluation of the Therapeutic Effect of Contrast-Enhanced Ultrasound on Different Types of Knee Osteoarthritis in the Elderly
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作者 Na Wen Yingcong Xiao 《Journal of Biosciences and Medicines》 CAS 2023年第5期1-8,共8页
Objective: To evaluate the curative effect of the Traditional Chinese Medicine (TCM) external therapy on knee osteoarthritis patients with different TCM constitutions using musculoskeletal ultrasonography and contrast... Objective: To evaluate the curative effect of the Traditional Chinese Medicine (TCM) external therapy on knee osteoarthritis patients with different TCM constitutions using musculoskeletal ultrasonography and contrast-enhanced ultrasonography, and to explore the application value of contrast-enhanced ultrasonography in knee joint diseases. Methods: A total of 57 patients diagnosed with knee osteoarthritis in Shaanxi University of Traditional Chinese Medicine from December 2019 to May 2021 were collected, and they were divided into qi stagnation and blood stasis type group (23 cases) and cold-dampness obstruction type group (34 cases) according to the traditional Chinese medicine method. All patients were given acupuncture combined with TCM fumigation and washing. All patients underwent musculoskeletal ultrasonography and contrast-enhanced ultrasonography before and after treatment, observed and recorded relevant data, and compared the treatment effects between the two groups. Results: 85.96% (49/57) of knee osteoarthritis (KOA) patients had suprapatellar bursa effusion, 42.1% (24/57) had iliotibial band bursae effusion, some of which had poor sound transmission, and thickened synovium was seen in most effusions, 33.33% (19/57) had osteophyte formation. Compared with before treatment, the depth of suprapatellar sac effusion in the Qi stagnation and blood stasis type group decreased after treatment (P Conclusion: Musculoskeletal contrast-enhanced ultrasonography was used to quantitatively evaluate the efficacy of TCM external therapy on KOA for different TCM constitutions. Dynamic observation of synovial lesions of knee osteoarthritis provides a valuable imaging method for evaluating the efficacy of traditional Chinese medicine. 展开更多
关键词 Contrast-Enhanced Ultrasound External Treatment of Traditional Chinese Medicine Knee Osteoarthritis Qi Stagnation and Blood Stasis Type Cold-Dampness Obstruction Type
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Classification of Natural Types of Quercus variabilis
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作者 Jianyun ZHOU 《Plant Diseases and Pests》 CAS 2023年第2期23-26,共4页
[Objectives]The paper was to classify natural types of Quercus variabilis and to study its regularity of variation.[Methods]Through the analysis of correlation coefficient matrix of tree age,DBH,tree height,breast hei... [Objectives]The paper was to classify natural types of Quercus variabilis and to study its regularity of variation.[Methods]Through the analysis of correlation coefficient matrix of tree age,DBH,tree height,breast height and bark thickness,petiole length,leaf width and leaf length,the breast height and bark thickness and petiole length were chosen as the main indices for classifying natural types of Q.variabilis.[Results]There were 4 natural types of Q.variabilis in Shaanxi Province,including long-petiole-thick-bark type,short-petiole-thick-bark type,long-petiole-thin-bark type and short-petiole-thin-bark type.The short-petiole-thick-bark type accounted for the largest proportion in Q.variabilis population(34.44%).On the northern slope of Bashan Mountains and the Huanglong Mountains,the short-petiole-thick-bark type was the dominant type,while on the northern slope of Qinling Mountains the long-petiole-thick-bark type accounted for a larger proportion.[Conclusions]This study will provide a basic foundation for making full use of excellent types of Q.variabilis natural resources. 展开更多
关键词 Quercus variabilis Natural type CLASSIFICATION Shaanxi Province
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Classification of vegetative types in Changbai Mountain based on optical and microwave remote sensing data
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作者 YANG Ying XU Mengxia +3 位作者 LI Sheng WANG Mingchang LIU Ziwei ZHAO Shijun 《Global Geology》 2023年第2期122-132,共11页
Highly accurate vegetative type distribution information is of great significance for forestry resource monitoring and management.In order to improve the classification accuracy of forest types,Sentinel-1 and 2 data o... Highly accurate vegetative type distribution information is of great significance for forestry resource monitoring and management.In order to improve the classification accuracy of forest types,Sentinel-1 and 2 data of Changbai Mountain protection development zone were selected,and combined with DEM to construct a multi-featured random forest type classification model incorporating fusing intensity,texture,spectral,vegetation index and topography information and using random forest Gini index(GI)for optimization.The overall accuracy of classification was 94.60%and the Kappa coefficient was 0.933.Comparing the classification results before and after feature optimization,it shows that feature optimization has a greater impact on the classification accuracy.Comparing the classification results of random forest,maximum likelihood method and CART decision tree under the same conditions,it shows that the random forest has a higher performance and can be applied to forestry research work such as forest resource survey and monitoring. 展开更多
关键词 vegetative type classification random forest radar data optical data
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