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Hybrid ecophysiological growth model for deciduous Populus tomentosa plantation in northern China
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作者 Serajis Salekin Mark Bloomberg +4 位作者 Benye Xi Jinqiang Liu Yang Liu Doudou Li Euan G.Mason 《Forest Ecosystems》 2025年第1期112-120,共9页
Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to... Short rotation plantation forestry(SRF)is being widely adopted to increase wood production,in order to meet global demand for wood products.However,to ensure maximum gains from SRF,optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth.Hybrid ecophysiological models,such as potentially useable light sum equation(PULSE)models,are useful tools requiring minimal input data that meet the requirements of SRF.PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data.Therefore,it is prudent to question:can adding detailed soil and climatic data reduce errors in this type of model?In addition,PULSE techniques have not been used to model deciduous species,which are a challenge for ecophysiological models due to their phenology.This study developed a PULSE model for a clonal Populus tomentosa plantation in northern China using detailed edaphic and climatic data.The results showed high precision and low bias in height(m)and basal area(m^(2)·ha^(-1))predictions.While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding,the study suggested that local climatic data could also be employed.The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias. 展开更多
关键词 Growth-yield model Populus species Hybrid ecophysiological modelling Deciduous trees PHENOLOGY
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Fibroblast growth factors and endometrial decidualization:models,mechanisms,and related pathologies
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作者 Xueni ZHANG Yidi MO +2 位作者 Chunbin LU Zhijian SU Xiaokun LI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 2025年第6期573-588,共16页
The onset of pregnancy is marked by the formation of a zygote,while the culmination of gestation is manifested by the delivery of a fetus.Meanwhile,a successful pregnancy entails a meticulously coordinated sequence of... The onset of pregnancy is marked by the formation of a zygote,while the culmination of gestation is manifested by the delivery of a fetus.Meanwhile,a successful pregnancy entails a meticulously coordinated sequence of events from embryo implantation to sustained decidualization of the uterus to placental development and childbirth.The decidual reaction,a pivotal process occurring within the endometrium during pregnancy,is finely regulated by sex steroids and cytokines.Notably,fibroblast growth factors(FGFs),particularly FGF2,play a critical role in this physiological cascade.Dysregulated FGF expression may trigger inadequate decidualization,precipitating a spectrum of adverse pregnancy outcomes,including preeclampsia,recurrent implantation failure,and miscarriage.Furthermore,the human decidua,distinct from most mammalian species and similar to great apes,undergoes regular cycles of formation and shedding,independent of the presence of the embryo in the endometrium.This process is also tightly controlled by various FGFs.In this review,we comprehensively compare diverse research decidualization models,delineate the trend of endometrial FGFs during the menstrual cycle,and provide a synopsis of endometrial diseases triggered by FGF dysregulation. 展开更多
关键词 Fibroblast growth factor(FGF) DECIDUALIZATION PREGNANCY Adverse pregnancy outcome
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Light Use Efficiency Model Based on Chlorophyll Content Better Captures Seasonal Gross Primary Production Dynamics of Deciduous Broadleaf Forests
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作者 YANG Rongjuan LIU Ronggao +3 位作者 LIU Yang CHEN Jingming XU Mingzhu HE Jiaying 《Chinese Geographical Science》 2025年第1期55-72,共18页
Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by vegetation.At present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes... Gross primary production(GPP)is a crucial indicator representing the absorption of atmospheric CO_(2) by vegetation.At present,the estimation of GPP by remote sensing is mainly based on leaf-related vegetation indexes and leaf-related biophysical para-meter leaf area index(LAI),which are not completely synchronized in seasonality with GPP.In this study,we proposed chlorophyll content-based light use efficiency model(CC-LUE)to improve GPP estimates,as chlorophyll is the direct site of photosynthesis,and only the light absorbed by chlorophyll is used in the photosynthetic process.The CC-LUE model is constructed by establishing a linear correlation between satellite-derived canopy chlorophyll content(Chlcanopy)and FPAR.This method was calibrated and validated utiliz-ing 7-d averaged in-situ GPP data from 14 eddy covariance flux towers covering deciduous broadleaf forest ecosystems across five dif-ferent climate zones.Results showed a relatively robust seasonal consistency between Chlcanopy with GPP in deciduous broadleaf forests under different climatic conditions.The CC-LUE model explained 88% of the in-situ GPP seasonality for all validation site-year and 56.0% of in-situ GPP variations through the growing season,outperforming the three widely used LUE models(MODIS-GPP algorithm,Vegetation Photosynthesis Model(VPM),and the eddy covariance-light use efficiency model(EC-LUE)).Additionally,the CC-LUE model(RMSE=0.50 g C/(m^(2)·d))significantly improved the underestimation of GPP during the growing season in semi-arid region,re-markably decreasing the root mean square error of averaged growing season GPP simulation and in-situ GPP by 75.4%,73.4%,and 37.5%,compared with MOD17(RMSE=2.03 g C/(m^(2)·d)),VPM(RMSE=1.88 g C/(m^(2)·d)),and EC-LUE(RMSE=0.80 g C/(m^(2)·d))model.The chlorophyll-based method proved superior in capturing the seasonal variations of GPP in forest ecosystems,thereby provid-ing the possibility of a more precise depiction of forest seasonal carbon uptake. 展开更多
关键词 canopy chlorophyll content(Chlcanopy) PHOTOSYNTHESIS gross primary production(GPP) light use efficiency(LUE)model seasonal dynamics deciduous broadleaf forest(DBF)
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Environment-driven intraspecific variation shows coordination of functional traits of deciduous oaks among and within different biological levels
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作者 Yutong Lin Yuan Lai +6 位作者 Songbo Tang Jeannine Cavender-Bares Josep Peñuelas Jordi Sardans Jianfeng Liu Lingling Zhang Yuanwen Kuang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期95-109,共15页
Deciduous oaks(Quercus spp.)are distributed from subalpine to tropical regions in the northern hemi-sphere and have important roles as carbon sinks and in climate change mitigation.Determining variations in plant func... Deciduous oaks(Quercus spp.)are distributed from subalpine to tropical regions in the northern hemi-sphere and have important roles as carbon sinks and in climate change mitigation.Determining variations in plant functional traits at multiple biological levels and linking them to environmental variables across geographical ranges is important for forecasting range-shifts of broadly-distrib-uted species under climate change.We sampled leaves of five deciduous Quercus spp.covering approximately 20°of latitude(~21°N-41°N)and 20 longitude(~99°E-119°E)across China and measured 12 plant functional traits at different biological levels.The traits varied distinctively,either within each biological level or among different levels driven by climatic and edaphic variables.Traits at the organ level were significantly correlated with those at the cellular and tissue levels,while traits at the whole-plant level only correlated with those at the tissue level.The Quercus species responded to changing environments by regulating stomatal size,leaf thickness and the palisade mesophyll thickness to leaf thickness ratios with contrasting degree of effect to adjust the whole-plant functioning,i.e.,intrinsic water use efficiency(iWUE),carbon supply and nitrogen availability.The results suggest that these deciduous Quercus spp.will maintain vigour by increasing iWUE when subjected to large temperature changes and insufficient moisture,and by accu-mulating leaf non-structural carbohydrates under drought conditions.The findings provide new insights into the inher-ent variation and trait coordination of widely distributed tree species in the context of climate change. 展开更多
关键词 Climate gradient Intraspecific variation Plant functional traits Deciduous Quercus species Whole-plant function
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Variability and determinants of vascular plant species composition in patches of old managed oak forest stands dispersed within Scots pine monocultures
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作者 Ewa Stefanska-Krzaczek Rafał Krzaczek +1 位作者 Natalia Mazurek Damian Chmura 《Forest Ecosystems》 CSCD 2024年第6期793-804,共12页
In the temperate zone of Europe,Scots pine forests are expected to occupy the poorest habitats which are unfavourable for deciduous trees.However,as a result of deforestation of the most fertile habitats and the prefe... In the temperate zone of Europe,Scots pine forests are expected to occupy the poorest habitats which are unfavourable for deciduous trees.However,as a result of deforestation of the most fertile habitats and the preference for Pinus sylvestris in silviculture,pine forests have become the dominant feature of the landscape in Central Europe.As a result,the area of optimal habitat for deciduous forest flora has been significantly reduced.Nevertheless,remnant patches of deciduous forest persist as habitat islands within extensive pine forest complexes and may serve as important refugia for meso-and eutrophilic forest species.However,the factors that contribute to the variation in species composition of such habitat islands and their role in maintaining biodiversity remain poorly understood.This paper aims to fill this knowledge gap.The studied deciduous(oak)stands exhibited a diverse vegetation,with species composition influenced by overstorey attributes,oak age,patch location,and the area and circularity of the deciduous forest.Species traits related to environmental variables included mainly preferences for closed or open forests,requirements for soil moisture,reaction,and fertility,and requirements for light conditions.The key message from our research is that oak islands are not simply patches of trees that are different from the surrounding area.Instead,they represent distinct plant communities that have developed to adapt to the prevailing environmental conditions by recruiting species with particular traits.The presence of oak islands within Scots pine monocultures is therefore important for increasing the diversity of the forest complex.The most relevant recommendation from our research for forest management is to maintain as many patches of deciduous tree stands as possible within a single pine forest complex,as even small habitat islands can make a significant contribution to the biodiversity of the forest complex. 展开更多
关键词 Habitat islands Deciduous forests Indicator species Environmental variables Species traits
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Evaluation of the Effectiveness and Safety of One-Time Endodontics in the Treatment of Chronic Apical Periodontitis with Sinus Tract in Pediatric Deciduous Teeth
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作者 Yi Liu 《Journal of Clinical and Nursing Research》 2024年第6期111-116,共6页
Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apica... Objective:To observe the effectiveness and safety of one-time endodontics in the treatment of chronic apical periodontitis with sinus tract in pediatric deciduous teeth.Methods:109 cases of children with chronic apical periodontitis with sinus tract in the deciduous teeth treated in our hospital from January 2022 to December 2023 were selected and grouped by the randomized numerical table method,with 54 cases in the experimental group and 55 cases in the control group.The experimental group was treated with one-time endodontics and the control group was treated with conventional endodontics.Results:After the treatment,the total effective rate of treatment was higher in the experimental group than in the control group(P<0.05);the incidence of adverse events was lower in the experimental group than in the control group(P<0.05);the satisfaction of the children's family members was higher in the experimental group than in the control group(P<0.05);the pain duration was lower in the experimental group than in the control group(P<0.05).Conclusion:In the experimental group,children with chronic apical periodontitis with sinus tract of the deciduous teeth were given one-time endodontic treatment,and the results of its implementation were relatively good. 展开更多
关键词 One-time endodontics Chronic apical periodontitis with sinus tract Pediatric deciduous teeth Therapeutic effectiveness SAFETY
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Regulation of Alternative Splicing by PARP1 in HTR-8/Svneo Cells:Implications for Placental Development and Spontaneous Abortion
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作者 Jing ZHAO De-hua YANG +2 位作者 Yeerdeng QIEQIEKE Ning-ning HAN Hasitiyaer JIEENSI 《Current Medical Science》 2024年第6期1325-1336,共12页
Objective:Alternative splicing affects gene expression during placental development.The present study aimed to identify poly(ADP-ribose)polymerase 1(PARP1)-regulated alternative splicing events in HTR-8/Svneo cells.Me... Objective:Alternative splicing affects gene expression during placental development.The present study aimed to identify poly(ADP-ribose)polymerase 1(PARP1)-regulated alternative splicing events in HTR-8/Svneo cells.Methods:Decidual tissues were collected from women with induced abortion and spontaneous abortion.PARP1 transcription was quantified by RT-qPCR.Small interfering RNA(siRNA)was used to knock down the PARP1 expression in HTR-8/Svneo cells.The transfection efficiency was verified by RT-qPCR and Western blotting.Total RNA was extracted,and the RNA-sequencing approach was used to identify alternative splicing events and transcriptomes.The PARP1 knockdown-induced differentially expressed genes with changes in alternative splicing events were quantified by RT-qPCR.Functional analysis,which included the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways,was performed.Results:The PARP1 mRNA expression increased in decidual tissues in the spontaneous abortion group,when compared to the induced abortion group.However,the PARP1 knockdown significantly downregulated 1491 genes and upregulated 881 genes in HTR-8/Svneo cells.Furthermore,227 genes that underwent alternative splicing were identified,and these were differentially expressed in siPARP1 cells,when compared to siNC cells.Conclusion:The functional analysis revealed that these alternative splicing genes affected the functional phenotypes of extravillous cytotrophoblasts.Furthermore,the PARP1 knockdown led to alterations in gene expression and specific alternative splicing patterns in extravillous trophoblasts. 展开更多
关键词 poly(ADP-ribose)polymerase 1(PARP1) alternative splicing extravillous trophoblasts spontaneous abortion gene expression decidual tissues
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落叶果树需冷量及其估算模型研究进展 被引量:22
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作者 赵海亮 赵文东 +3 位作者 高东升 于德林 孙凌俊 高圣华 《北方果树》 2007年第6期1-3,共3页
  落叶果树的需冷量得到满足,才能顺利完成自然休眠,进行下一个生长发育循环(尤其是正常开花结果),否则其他环境条件再适宜,果树也不萌芽开花,即使萌芽也不整齐,生长结果不良,达不到促成栽培的目的[1].因此,对落叶果树需冷量及其估算...   落叶果树的需冷量得到满足,才能顺利完成自然休眠,进行下一个生长发育循环(尤其是正常开花结果),否则其他环境条件再适宜,果树也不萌芽开花,即使萌芽也不整齐,生长结果不良,达不到促成栽培的目的[1].因此,对落叶果树需冷量及其估算的研究至关重要,成为落叶果树设施栽培成败的关键.本文仅就需冷量估算模型进行介绍,以期为设施栽培和更完善的需冷量估算提供理论依据.…… 展开更多
关键词 Deciduous fruit tree Chilling requirement Estimating models
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田林老山中山两类森林凋落物研究 被引量:28
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作者 梁宏温 《生态学杂志》 CAS CSCD 北大核心 1994年第1期21-26,共6页
田林老山中山两类森林凋落物研究梁宏温(广西农学院林学分院,南宁530001)StudiesontheLitterfallofTwoForestTypcsinMid—AltitudeofLaoshanMountaini... 田林老山中山两类森林凋落物研究梁宏温(广西农学院林学分院,南宁530001)StudiesontheLitterfallofTwoForestTypcsinMid—AltitudeofLaoshanMountaininTianlinCounty.¥L... 展开更多
关键词 evergreen and deciduous broadleaved mixed forest.Chinese fir plantation litterfall nutrient element return decompositon rate.
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Assessing the concentration and potential health risk of heavy metals in China's main deciduous fruits 被引量:12
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作者 NIE Ji-yun KUANG Li-xue +9 位作者 LI Zhi-xia XU Wei-hua WANG Cheng CHEN Qiu-sheng LI An ZHAO Xu-bo XIE Han-zhong ZHAO Duo-yong WU Yong-long CHENG Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1645-1655,共11页
To assess levels of contamination and human health risk, we analyzed the concentrations of the heavy metals lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) in China’s main deciduous fruits-apple, pear... To assess levels of contamination and human health risk, we analyzed the concentrations of the heavy metals lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) in China’s main deciduous fruits-apple, pear, peach, grape, and jujube. The concentration order of the heavy metals was Ni〉Cr〉Pb〉Cd. In 97.5% of the samples, heavy metal concentrations were within the maximum permissible limits. Among the fruits studied, the heavy metal concentrations in jujube and peach proved to be the highest, and those in grape proved to be the lowest. Only 2.2% of the samples were poluted by Ni, only 0.4% of the samples were poluted by Pb, and no samples were poluted by Cd or Cr. Compared with the other fruits, the combined heavy metal polution was signiifcantly higher (P〈0.05) in peach and signiifcantly lower (P〈0.05) in grape. For the combined heavy metal polution, 96.9% of the samples were at safe level, 2.32% at warning level, 0.65% at light level, and 0.13% at moderate level. In the fruits studied, the contribution of heavy metals to the daily intake rates (DIR) folowed the order of Ni〉Cr〉Pb〉Cd. The highest DIR came from apple, while the lowest DIR came from grape. For each of the heavy metals, the total DIR from ifve studied fruits corresponded to no more than 1.1% of the tolerable daily intake, indicating that no signiifcant adverse health effects are expected from the heavy metals and the fruits studied. The target hazard quotients and the total target hazard quotients demonstrated that none of the analyzed heavy metals may pose risk to consumers through the fruits studied. The highest risk was posed by apple, folowed in decreasing order by peach and pear, jujube, and grape. We suggest that the main deciduous fruits (apple, pear, peach, grape, and jujube) of China’s main producing areas are safe to eat. 展开更多
关键词 deciduous fruits heavy metals health risk assessment China
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Microbial Biomass C,N and P in Disturbed Dry Tropical Forest Soils,India 被引量:9
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作者 J.S.SINGH D.P.SINGH A.K.KASHYAP 《Pedosphere》 SCIE CAS CSCD 2010年第6期780-788,共9页
Variations in microbial biomass C (MB-C),N (MB-N) and P (MB-P) along a gradient of different dominant vegeta- tion covers (natural forest,mixed deciduous forest,disturbed savanna and grassland ecosystems) in dry tropi... Variations in microbial biomass C (MB-C),N (MB-N) and P (MB-P) along a gradient of different dominant vegeta- tion covers (natural forest,mixed deciduous forest,disturbed savanna and grassland ecosystems) in dry tropical soils of Vindhyan Plateau,India were studied from January 2005 to December 2005.The water holding capacity,organic C,total N,total P and soil moisture content were comparatively higher in forest soils than in the savanna and grassland sites.Across different study sites the mean annual MB-C,MB-N and MB-P at 0-15 cm soil depth varied from 312.05 ± 4.22 to 653.40 ± 3.17,32.16 ± 6.25 to 75.66 ± 7.21 and 18.94 ± 2.94 to 30.83 ± 23.08 μg g ?1 dry soil,respectively.At all the investigated sites,the maximum MB-C,MB-N and MB-P occurred during the dry period (summer season) and the minimum in wet period (rainy season).In the present study,soil MB-C,MB-N and MB-P were higher at the forest sites compared to savanna and grassland sites.The differences in MB-C,MB-N and MB-P were significant (P < 0.001) among sites and seasons.The MB-C (P < 0.0001),MB-N (P < 0.001) and MB-P (P < 0.0001) were positively correlated with organic C,while the relationship between soil moisture and MB-C,MB-N and MB-P (P < 0.001,P < 0.01 and P < 0.0001,respectively) was negative.The decreasing order of MB-C,MB-N and MB-P along study ecosystems was natural forest > mixed deciduous forest > savanna > grassland.The results suggested that deforestation and land use practices (conversion of forest into savanna and grassland) caused the alterations in soil properties,which as a consequence,led to reduction in soil nutrients and MB-C,MB-N and MB-P in the soil of disturbed sites (grassland and savanna) compared to undisturbed forest ecosystems. 展开更多
关键词 deciduous forest GRASSLAND SAVANNA soil moisture VEGETATION
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Effects of Chinese Fir,Loblolly Pine and Deciduous Oak Forests on Nutrient States of Soils in Northern Subtro-pics of China 被引量:10
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作者 LUO RU-YING and GAO ZHI-QIN(Nanjing Forestry University, Nanjing 210057 (China)) 《Pedosphere》 SCIE CAS CSCD 1994年第1期1-10,共10页
This paper deals with a study on the effects of Chinese fir, loblolly pine and deciduous oak forests on thenutrient status of soils in northern subtropics of China, adopting the principle of forest ecology in the case... This paper deals with a study on the effects of Chinese fir, loblolly pine and deciduous oak forests on thenutrient status of soils in northern subtropics of China, adopting the principle of forest ecology in the caseof similar climate and soil type. The experimental area was situated in the Xiashu Experimental Centre ofForest, where the soil is yellow-brown soil derived from siliceous slope wash. Sample plots of these 3 standswere established to study the nutrient status in litter, the amount of nutrient uptake by roots, the quantityof nutrient output by percolating water outside the deep layer of soil, and the seasonal dynamics of availablenutrient in surface soil. It was shown that the intensity of nutrient cycling in soil under deciduous oak wasthe highest, and the effect of oak in improving soil fertility was the best. The result of improving soil fertilityby Chinese fir was the most inferior, though the intensity of nutrient cycling under that stand was higherthan that under loblolly pine stand. The influence of loblolly pine on the improvement of soil fertility wasbetter than that of Chinese fir, in spite of its lowest intensity of nutrient cycling. 展开更多
关键词 Chinese fir deciduous oak LITTER loblolly pine nutrient status
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Transplantation of stem cells from human exfoliated deciduous teeth for bone regeneration in the dog mandibular defect 被引量:9
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作者 Ali Behnia Abbas Haghighat +2 位作者 Ardeshir Talebi Nosrat Nourbakhsh Fariba Heidari 《World Journal of Stem Cells》 SCIE CAS 2014年第4期505-510,共6页
AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been i... AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been isolated 5 years ago from human exfoliated deciduous teeth. The undifferentiated stem cells were seeded into mandibular bone through-andthrough defects of 4 dogs. Similar defects in control group were filled with cell-free collagen scaffold. After 12 wk, biopsies were taken and morphometric analysis was performed. The percentage of new bone formation and foreign body reaction were measured in each case. The data were subject to statistical analysis using the Mann-Whitney U and Kruskalwalis statistical tests. Differences at P < 0.05 was considered as significant level.RESULTS: There were no significant differences between control and SHED-seeded groups in connective tissue(P = 0.248), woven bone(P = 0.248) and compact bone(P = 0.082). There were not any side effects in transplanted SHED group such as teratoma or malignancy and abnormalities in this period.CONCLUSION: SHEDs which had been isolated and characterized 5 years ago and stored with cryopreservation banking were capable of proliferation and osteogenesis after 5 years, and no immune response was observed after three months of seeded SHEDs. 展开更多
关键词 BONE REGENERATION Isolation Stem cells from human EXFOLIATED DECIDUOUS teeth
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Pressure from the lips and the tongue in children with class III malocclusion 被引量:6
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作者 RUAN Wen-hua SU Ji-mei YE Xiao-wei 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第5期296-301,共6页
Objective: To discuss possible relationships between class In malocclusion and perioral forces by measuring the pressure from the lips and the tongue of children with class nI malocclusion. Methods: Thirty-one child... Objective: To discuss possible relationships between class In malocclusion and perioral forces by measuring the pressure from the lips and the tongue of children with class nI malocclusion. Methods: Thirty-one children with class In malocclusion were investigated and their perioral forces were measured at rest and during swallowing under natural head position by a custom-made miniperioral force computer measuring system. Results: The resting pressures exerted on the labial side and palatine side of the upper lett incisor, as well as the labial side and lingual side of the lower lett incisor, were 0 g/cm^2, 0 g/cm^2, 0.57 g/cm^2 and 0.23 g/cm^2, respectively. Correspondingly, the swallowing forces were 2.87 g/cm^2, 5.97 g/cm^2, 4.09 g/cm^2 and 7.89 g/cm^2, respectively. No statistical difference between muscular pressure and gender existed. During swallowing, the lingual forces were significantly higher than the labial forces (P〈0.01), however, at rest there was no significantly different force between these two sides. Compared to the normal occlusion patients, children with class Ⅲ malocclusion had lower pedoral forces. The upper labial resting forces (P〈0.01), the lower labial resting forces (P〈0.05) and all the swallowing pressures from the lips and the tongue (P〈0.01) showed statistical differences between the two different occlusion conditions. Meanwhile, no significant difference was found for the resting pressure from the tongue between class Ⅲ malocclusion and normal occlusion. Conclusion: Patients with class Ⅲ malocclusion have lower perioral forces and this muscle hypofunction may be secondary to the spatial relations of the jaws. The findings support the spatial matrix hypothesis. 展开更多
关键词 Deciduous dentition Perioral force Pressure transducer Class malocclusion
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Post-fire soil nutrient dynamics in a tropical dry deciduous forest of Western Ghats,India 被引量:4
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作者 Satyam Verma Dharmatma Singh +1 位作者 Ajeet Kumar Singh Shanmuganathan Jayakumar 《Forest Ecosystems》 SCIE CSCD 2019年第1期67-75,共9页
Background: The effect of forest fire on soil is complex and relatively less understood than its above ground effect.Understanding the effect of fire on forest soils can allow improving management of valuable forest e... Background: The effect of forest fire on soil is complex and relatively less understood than its above ground effect.Understanding the effect of fire on forest soils can allow improving management of valuable forest ecosystems as adequate and proper information is very important for efficient management. We have studied the recovery of soil properties after fire, using a chronosequence approach(two, five and fifteen years after fire and control). Soil samples were collected from each plot of four fire patches(B0, B2, B5 & B15) from three different depths viz. 0–10(Top), 10–20(Middle), and 20–30 cm(Bottom).Results: Soil organic carbon was lower than unburned plots after the fire and could not recover to the level of unburned plot(B0) even in 15 years. Total N, available P, and extractable K were lower 2-years and 5-years after the fire but are higher than unburned plot after 15-years. Available nitrogen(NO_3^- and NH_4^+) remain unchanged or higher than B0 in burned patches. Soil pH, Bulk Density, Water Holding Capacity, and Electrical Conductivity was lower initially after the fire. Forest fires have affected soil properties considerably. The response of soil properties varied with years after fire and soil depth.Conclusion: Forest fires occur very frequently in the study area. Significant quantities of carbon and total nitrogen are lost to the atmosphere by burning of litter, duff, and soil OM. Because nitrogen is one of the most important soil nutrients, the recapture of N lost by volatilization during a fire must receive special attention. Long-term studies are required to better understand the recovery of soil nitrogen. 展开更多
关键词 Soil properties Western Ghats TROPICAL DRY DECIDUOUS FOREST FOREST fire FOREST SOILS
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Effect of nitrogen levels on photosynthetic parameters,morphological and chemical characters of saplings and trees in a temperate forest 被引量:4
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作者 Jinwei Sun Fuqi Yao +2 位作者 Jiabing Wu Pingcang Zhang Wensheng Xu 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1481-1488,共8页
Exploring the response differences of leaf physiology parameters to enhanced nitrogen deposition between saplings and trees is vital for predicting the variations of terrestrial ecosystem structure and function under ... Exploring the response differences of leaf physiology parameters to enhanced nitrogen deposition between saplings and trees is vital for predicting the variations of terrestrial ecosystem structure and function under future global climate change. In this study, the ecophysiological parameters of saplings and trees of Fraxinus mandshurica Rupr. were measured at different levels of nitrogen addition in a temperate forest. The results show that ecophysiological parameters maximum net photosynthetic rate(Pmax), apparent quantum efficiency(a), dark respiration(Rd), light saturation point(Lsp), photosynthetic nitrogen use efficiency(PNUE),specific leaf area(SLA)and stomatal conductance under saturated light intensity(Gsmax) were higher in saplings than in trees. These physiological parameters and not Nleaf(leaf nitrogen content)led to relatively lower Pmaxand Rdin trees. For both saplings and trees, low and median nitrogen addition(23 and 46 kg ha-1a-1) resulted in significant increases in Pmax, Rd, Lsp, Chl, PNUE, SLA and Gsmax. These parameters tended to decline under high additions of nitrogen(69 kg ha-1a-1),whereas Nleaf was always enhanced with increasing nitrogen. Variations in Pmax and Rd with increasing nitrogen were attributed to variations in the strongly related parameters of, Lsp, Chl, PNUE, SLA and Gsmax. Overall, the response sensitivity of physiological parameters to enhanced nitrogen levels was lower in trees compared with saplings. 展开更多
关键词 Physiology parameters Added nitrogen SAPLINGS Trees Deciduous broadleaved species
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Tropical deciduous forest in Yunnan,southwestern China:Implications for geological and climatic histories from a little-known forest formation 被引量:4
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作者 Hua Zhu Peter Ashton +2 位作者 Bojian Gu Shisun Zhou Yunhong Tan 《Plant Diversity》 SCIE CAS CSCD 2021年第6期444-451,共8页
In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper... In the southern mountain ranges of Yunnan province,China,deep valleys of several large rivers create rain shadows with hot dry summers,and are locally designated tropical;towards the north,notably in the Lancang(Upper Mekong)valley,these regions may experience frost during winter.The woody forest canopy of these valleys is predominantly deciduous,with evergreen elements in the north,where the canopy is open and the forest savanna-like.However,we here present tall forest with a closed deciduous canopy and semi-evergreen subcanopy observed in hot dry valleys of these rivers and their tributaries in the tropical south.The structure and physiognomy of these forests resemble the tall(moist)deciduous forest formation widespread in South Asia and Indo-Burma.Furthermore,these forests are largely composed of tropical elements at both the generic(80%)and the species level(>70%),indicating that these forests are indeed tropical.We originally hypothesized that these isolated forests represent refugia of a pre-Holocene extension of tall(moist)deciduous forest formation of South Asia and Indo-Burma.The sample plot we established to test this hypothesis confirmed that these forests share the structure and physiognomy of the tall(moist)deciduous forest formation;however,the plots also showed that these forests lack the characteristic and dominant species of the formation's Indo-Burmese range.The tree flora,in particular,indicates that both deciduous and evergreen elements are instead mostly derived from the adjacent tropical semi-evergreen forests of tropical southern China;yet they also include an important endemic element,which implies that these forests have survived as refuges possibly since the Pliocene.The exceptional representation of evergreen elements in these forests indicates that they have rarely been subject to hot fires or domestic cattle browsing,adding to the unique nature of the forests and further justifying their strict conservation. 展开更多
关键词 Floristic composition PHYSIOGNOMY BIOGEOGRAPHY Independent species assembly Tall deciduous forest Southwestern China
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Do vegetative and reproductive phenophases of deciduous tropical species respond similarly to rainfall pulses? 被引量:3
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作者 A.P.Silveira F.S.Araújo F.R.Martins 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第4期643-651,共9页
Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in synchrony and inte... Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in synchrony and intensity of phenophases, as strategy for large variations in duration and intensity of rainfall pulses. Nevertheless, it remains unknown how phenophases of deciduous trees of the Brazilian semi-arid region respond to rainfall variations. The phenology of Cordia oncocalyx was monitored in deciduous thorny woodland (Caatinga), from April 2009 to March 2011, and was correlated with rainfall, soil humidity, temperature, and photoperiod. The rainy years 2009 and 2011 exhibited higher duration of rainfall pulses and lower frequency of interpulses, but in 2010 pulse duration and total rainfall were lower. Circular statistics showed leaf flush followed by flowering and fruiting in the rainy season, and leaf fall and seed dispersal in the dry season. 展开更多
关键词 ASYNCHRONY circular analysis DECIDUOUS PHENOLOGY riskspreading seasonality.
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Effect of IFN-γ/IL-10 on IL-10 Receptor Expression of Human Decidual Stromal Cells in Early Pregnancy 被引量:6
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作者 Chang-ying XING Sui-qi GUI 《Journal of Reproduction and Contraception》 CAS 2006年第2期65-74,共10页
Objective To study the role of IFN-γ/IL-10 cytokines protein expression of human decidual stromal cells(DSC) vitro. on IL-10 receptor gene and in human early pregnancy in vitro. Methods Human DSC was isolated and c... Objective To study the role of IFN-γ/IL-10 cytokines protein expression of human decidual stromal cells(DSC) vitro. on IL-10 receptor gene and in human early pregnancy in vitro. Methods Human DSC was isolated and cultured in vitro, and the expression of IL-10R1 and IL-10R2 gene was analyzed after cells had been treated with TH2-type cytokines IL-10 and TH1-type cytokines IFN-γ within 60 rain with semiquantitative reverse transcriptase-PCR, then the influence of IL-10 and IFN-γ on expression of IL-10R protein was examined by first trimester DSC using flow cytometry. In addition, the vitality of DSC was detected by MTT. Results IL-10R1 mRNA levels of DSC treated with IL-10 (10 ng/ml) reached the peak level within 15 rain, and were significantly lower at 30 rain, then were not detected at 45 min. The expression of IL-10R1 were induced to moderate level by IFN-γ(10 ng/ml) within 30 rain, and reduced to undetected levels at 60 min. There was no significant difference of IL-10R2 expression (P〉0.05) between treated and not with the abovementioned cytokines. The IL-10R protein expression and vitality of DSC were significantly enhanced by IL-10 (10 ng/ml) and IFN-γ (10 ng/ml) which treated DSC 48 h (P〈0.05). Coneclusion IL-10 and IFN-γ may play an important role of biologic function in early pregnancy by influencing IL-10R expression of DSC. 展开更多
关键词 IL-10 IFN-Γ decidual stromal cell IL-10 receptor in vitro
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