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Impact of climate change on rice growth and yield in China:Analysis based on climate year type
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作者 Lunche Wang Danhua Zhong +2 位作者 Xinxin Chen Zigeng Niu Qian Cao 《Geography and Sustainability》 CSCD 2024年第4期548-560,共13页
Climate change threatens China’s rice production,making it crucial to assess the impact of climate change and climate year type(CYT)on rice production across regions to safeguard food security.The impact of climate c... Climate change threatens China’s rice production,making it crucial to assess the impact of climate change and climate year type(CYT)on rice production across regions to safeguard food security.The impact of climate change under nine CYTs with different combinations of temperature and precipitation on two rice cropping systems,including single rice and double rice(early and late rice)was evaluated.The results indicate that:(1)the Northeast region was expected to undergo the greatest warming of 2.03–2.48℃,and future climate conditions would be dominated by Warm-Humid,Warm-Normal,and Warm-Dry CYTs across all regions.(2)Climate change would significantly shorten anthesis days after sowing and maturity days after sowing of single rice by 6–12 days and 9–24 days,with little change observed for late rice(<1 day).Late rice yield suffered more from climate change compared to single and early rice yield,declining by 8.8%–16.13%.(3)Different CYTs exhibited varying impacts on rice yields.Yields were projected to decrease by approximately 4.765%to 18.645%in Warm-Humid,Warm-Normal,and Warm-Dry CYTs.Conversely,the Northeast region was anticipated to experience an increase in yield.(4)Relationships between rice yield and meteorological factors varied by region,variety,and CYT.Among the nine CYTs,high killing degree days,mean daily temperature,mean solar radiation and warm spell duration index were the main factors influencing changes in rice yield,explaining nearly 80%of yield change.Our results would help to develop adaptation strategies in different regions and rice cropping systems. 展开更多
关键词 RICE YIELD Climate year type Climate change China
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Assessment of growth monitoring among children younger than 5 years at early childhood development centres in Nelson Mandela Bay,South Africa
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作者 Shawn W.McLaren Liana Steenkamp Jessica Ronaasen 《Health Care Science》 2024年第1期32-40,共9页
Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trai... Introduction:Early childhood development(ECD)centres are important community hubs in South Africa and act as sites for community detection of childhood nutrition problems.This study aimed to assess the ability of trained ECD practitioners with optimal support to correctly classify the nutritional status of infants and young children at ECD centres in the Nelson Mandela Bay.Methods:A descriptive,cross-sectional study was used to collect data from 1645 infants and children at 88 ECD centres.Anthropometric measurements were taken by trained fieldworkers and growth monitoring and promotion infrastructure was audited at ECD centres.Results:Of the sample,4.4%(n=72)were underweight by weight for age Z-score(WAZ<-2)and 0.8%(n=13)were severely underweight(WAZ<-3).Results showed that 13.1%(n=214)were stunted by height for age Z-score(HAZ<-2)and 4.5%(n=74)were severely stunted(HAZ<-3).The prevalence of moderate acute malnutrition was 1.2%and severe acute malnutrition was 0.5%,while the prevalence of overweight was 9.2%and the prevalence of obesity was 4%.A significant level of agreement between the correct interpretation and the ECD practitioners'interpretation was observed across all the anthropometric indicators investigated.The true positive wasting cases had a mean mid-upper arm circumference(MUAC)of 14.6 cm,which may explain the high false negative rate found in terms of children identified with wasting,where ECD practitioners fail to use the weight for height Z-score(WHZ)interpretation for screening.Conclusion:By using ECD centres as hub to screen for malnutrition,it may contribute to the early identification of failure to thrive among young children.Although it was concerning that trained ECD practitioners are missing some children with an unacceptably high false negative rate,it may have been due to the fact that wasting in older children cannot be identified with MUAC alone and that accurate WFH plotting is needed.Onsite mentorship by governmental health workers may provide ECD practitioners with more confidence to screen children for growth failure based on regular WFH measurements.Moreover,ECD practitioners will be more confident to monitor the Road to Health booklets for missed vaccinations,vitamin A and deworming opportunities. 展开更多
关键词 early childhood development CHWs growth monitoring WASTING
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Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration
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作者 Ronglin Han Lanxin Luo +4 位作者 Caiyan Wei Yaru Qiao Jiming Xie Xianchao Pan Juan Xing 《Neural Regeneration Research》 SCIE CAS 2025年第5期1364-1376,共13页
Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to p... Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering. 展开更多
关键词 ALGINATE axon growth BIOMATERIALS extracellular matrix neural repair neurons NEUROREGENERATION POLYACRYLAMIDE POLYDIMETHYLSILOXANE stiffness
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Telencephalic stab wound injury induces regenerative angiogenesis and neurogenesis in zebrafish:unveiling the role of vascular endothelial growth factor signaling and microglia
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作者 Danielle Fernezelian Philippe Rondeau +1 位作者 Laura Gence Nicolas Diotel 《Neural Regeneration Research》 SCIE CAS 2025年第10期2938-2954,共17页
After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact... After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact are not well understood.In this work,we aimed to study the correlation between angiogenesis and neurogenesis after a telencephalic stab wound injury.To this end,we used zebrafish as a relevant model of neuroplasticity and brain repair mechanisms.First,using the Tg(fli1:EGFP×mpeg1.1:mCherry)zebrafish line,which enables visualization of blood vessels and microglia respectively,we analyzed regenerative angiogenesis from 1 to 21 days post-lesion.In parallel,we monitored brain cell proliferation in neurogenic niches localized in the ventricular zone by using immunohistochemistry.We found that after brain damage,the blood vessel area and width as well as expression of the fli1 transgene and vascular endothelial growth factor(vegfaa and vegfbb)were increased.At the same time,neural stem cell proliferation was also increased,peaking between 3 and 5 days post-lesion in a manner similar to angiogenesis,along with the recruitment of microglia.Then,through pharmacological manipulation by injecting an anti-angiogenic drug(Tivozanib)or Vegf at the lesion site,we demonstrated that blocking or activating Vegf signaling modulated both angiogenic and neurogenic processes,as well as microglial recruitment.Finally,we showed that inhibition of microglia by clodronate-containing liposome injection or dexamethasone treatment impairs regenerative neurogenesis,as previously described,as well as injury-induced angiogenesis.In conclusion,we have described regenerative angiogenesis in zebrafish for the first time and have highlighted the role of inflammation in this process.In addition,we have shown that both angiogenesis and neurogenesis are involved in brain repair and that microglia and inflammation-dependent mechanisms activated by Vegf signaling are important contributors to these processes.This study paves the way for a better understanding of the effect of Vegf on microglia and for studies aimed at promoting angiogenesis to improve brain plasticity after brain injury. 展开更多
关键词 ANGIOGENESIS cerebral damage inflammation NEUROGENESIS stab wound TELENCEPHALON vascular endothelial growth factor ZEBRAFISH
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Reevaluating health metrics:Unraveling the limitations of disabilityadjusted life years as an indicator in disease burden assessment
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作者 Ariel Beresniak Dominique Bremond-Gignac +1 位作者 Danielle Dupont Gerard Duru 《World Journal of Methodology》 2025年第1期14-19,共6页
In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and quali... In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and qualitative data,is grounded in preferences regarding disability status.This review delineates the algorithm used to calculate the value of the proposed DALY synthetic indicator and elucidates key methodological challenges associated with its application.In contrast to the quality-adjusted life years approach,derived from multi-attribute utility theory,the DALY stands as an independent synthetic indicator that adopts the assumptions of the Time Trade Off utility technique to define Disability Weights.Claiming to rely on no mathematical or economic theory,DALY users appear to have exempted themselves from verifying whether this indicator meets the classical properties required of all indicators,notably content validity,reliability,specificity,and sensitivity.The DALY concept emerged primarily to facilitate comparisons of the health impacts of various diseases globally within the framework of the Global Burden of Disease initiative,leading to numerous publications in international literature.Despite widespread adoption,the DALY synthetic indicator has prompted significant methodological concerns since its inception,manifesting in inconsistent and non-reproducible results.Given the substantial diffusion of the DALY indicator and its critical role in health impact assessments,a reassessment is warranted.This reconsideration is imperative for enhancing the robustness and reliability of public health decisionmaking processes. 展开更多
关键词 Disability adjusted life years Cost-utility analyses Outcome research Public health Burden of disease
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Transforming growth factor-beta 1 enhances discharge activity of cortical neurons
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作者 Zhihui Ren Tian Li +5 位作者 Xueer Liu Zelin Zhang Xiaoxuan Chen Weiqiang Chen Kangsheng Li Jiangtao Sheng 《Neural Regeneration Research》 SCIE CAS 2025年第2期548-556,共9页
Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may de... Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system. 展开更多
关键词 central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents
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Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex
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作者 Yan Li Peng Hao +6 位作者 Hongmei Duan Fei Hao Wen Zhao Yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第10期2923-2937,共15页
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne... The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries. 展开更多
关键词 adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation
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Branching and growth of plantings in fifth year of a seedling seed orchard of Masson pine (Pinus massoniana Lamb.) 被引量:3
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作者 赖焕林 王章荣 江瑞荣 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期28-32,83,共5页
The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number f... The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number for four consecutive years, diameter of branches of different ages, and diameter of stem where branch-whorl originates. For features of total growth and overall branching, no significant differences were found between families, except for DBH. For annual features, no significant differences were found in annual stem height growth, annual branch elongation in the year of elongation and diameter of branches. In the last four years, differences in number of branches were not significant in the first two years but were significant in the last two year; differences in stem diameter where branch-whorls grow were significant for the four consecutive years. Trend of annual growth and branching features of families can be divided into three types as increasing type, stable type and fluctuating type. Most of families have an increasing type with respect of annual height growth and annual branch elongation, while most families belong to a fluctuating type with annual branch number. The results indicated that in the fifth year after planted in seedling seed orchard, differences between families were mostly insignificant. This result may have two main explanations: one is the growth rhyme in early ages of Masson pine, the other one is the complex paternal components to form the open-pollinated families. Family selection seemed to be not useful based on the result. It is suggested to select some of families in the nursery instead of to use all the families when establishing seedling seed orchards with open-pollinated families from plus-trees. 展开更多
关键词 Pinus massoniana Lamb. Branching growth Seedling seed orchard
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Physical Growth of Children in Urban,Suburban and Rural China's Mainland:A Study of 20 Years' Change 被引量:3
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作者 LI Hui ZONG XinNan +1 位作者 ZHANG Jing ZHU ZongHan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第1期1-11,共11页
Objective To describe secular trends on physical growth of children in China during the year of 1985‐2005 and to analyze the urban‐suburban‐rural difference and its change. Methods The measurements of height, weigh... Objective To describe secular trends on physical growth of children in China during the year of 1985‐2005 and to analyze the urban‐suburban‐rural difference and its change. Methods The measurements of height, weight and chest circumference obtained from two serial national cross‐sectional surveys for children aged 0 to 7 years in China were used to analyze the secular trends, and the growth differences among urban, suburban and rural children were compared. Results The average weight and height for both boys and girls from urban, suburban and rural areas have significantly increased in most age groups during the past 20 years; The average chest circumference increased slightly, ranging from 0.0 to 2.0 cm. From 1985 to 2005, the urban‐suburban difference in height had become smaller, and that in weight showed similar trend for children under 3 years old but became larger after 3 years old; the suburban‐rural difference both in height and weight became larger after 6 months old. The increment per decade in height was the greatest in the suburban group while the greatest increment in weight was the urban group. Conclusion Positive secular trends were observed among urban, suburban and rural areas in Chinese children under 7 years old during the 1980s and the 2000s, reflecting a rapid socio‐economic development in China. 展开更多
关键词 growth Secular trends HEIGHT WEIGHT Chest circumference
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Study on the Growth Law of 23-year-old Castanopsis fissa Plantation
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作者 蒙奕奕 石晓蒙 +3 位作者 黄寿先 林正聪 谭飞燕 黄家华 《Agricultural Science & Technology》 CAS 2013年第12期1821-1825,共5页
This paper studies the growth law of 23-year-old Castanopsis fissa planta- tion in Haiming forest farm (Pingguo County, Baise City, Guangxi Province) with the method of stem analysis. The results show that the avera... This paper studies the growth law of 23-year-old Castanopsis fissa planta- tion in Haiming forest farm (Pingguo County, Baise City, Guangxi Province) with the method of stem analysis. The results show that the average DBH, tree height and volume of the 23-year-old C. fissa plantation are 19.4 cm, 20.4 m and 0.326 1 m3 respectively. The fast growing periods of DBH, tree height and volume are the 2^nd- 8^th, 6^th-11^th, 6^th-23^nd year. Annual increment curve and average increment curve of volume haven't intersected in the 23 years, which means the 23-year-old C. fissais plantation has not reached the quantitative mature age. The growth equations of DBH, tree height and volume are D=1.713 3T-0.050 6T2+0.000 7T2-1.942 2, H= 1.925 7T-0.039 8T2-2.489 0, V=-0.010 4T-0.002 4T2-4.084 8e^-0.005 T2+0.012 7. Ac- cording to the volume regression equation of Castanopsis fissa, it will reach quanti- tative maturity in the 24~ year. 展开更多
关键词 Castanopsis fissa PLANTATION growth Law growth Model
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Influence of mulching and tree shelters on 4-year survival and growth of zeen oak (Quercus canariensis) seedlings 被引量:1
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作者 Taher Mechergui Marta Pardos Douglass F.Jacobs 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期129-141,共13页
We assessed the effect of mulching and tree shelters on the establishment and early growth of zeen oak(Quercus canariensis Willd.) during the first 4 years after planting in Northwestern Tunisia. Five mulch types(Ital... We assessed the effect of mulching and tree shelters on the establishment and early growth of zeen oak(Quercus canariensis Willd.) during the first 4 years after planting in Northwestern Tunisia. Five mulch types(Italian Stone Pine(Pinus pinea L.), Lentisk(Pistacia lentiscus L.),and a combination of Italian Stone Pine and Lentisk(organic mulches), gravel(inorganic mulch) and control), and three tree shelter types(non-vented and vented tree shelters, and control) were tested. An increase in the number of internodes occurred under the gravel mulch, while a reduction in survival was found for the lentisk mulch. Tree shelters had no effect on survival, but increased mean height growth and reduced mean diameter growth during the 4 years(excepting a non-significant effect for vented tree shelter at year four). Comparison of the annual shoots and growth units(GU) between sheltered and unsheltered plants according to year of formation revealed two growth phases. In first phase, shoots were totally or partially inside the shelters; mean length of annual shoots and GU were greater for sheltered plants. The second phase was characterized by shoots emerging from shelters; mean length of annual shoots and GU were similar for all plants, with or without tree shelters. Results suggest that the use of tree shelters, particularly vented shelters, could contribute to the improvement of the artificial regeneration of zeen oak.The use of mulching alone or in combination with tree shelters did not improve zeen oak performance in the field. 展开更多
关键词 Zeen OAK MULCHING Tree SHELTERS Plantation SURVIVAL rate growth
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Analysis on the Growth Rhythm and Cold Tolerance of Five-Year Old <i>Eucalyptus benthamii</i>Plantation for Bioenergy 被引量:1
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作者 Aihua Yu Tom Gallagher 《Open Journal of Forestry》 2015年第6期585-592,共8页
A research plot of Eucalyptus benthamii was planted to evaluate this species’ ability to supply the emerging bioenergy markets that are developing in the southern U.S. The plot was planted in two different densities ... A research plot of Eucalyptus benthamii was planted to evaluate this species’ ability to supply the emerging bioenergy markets that are developing in the southern U.S. The plot was planted in two different densities to investigate the growth parameters and the cold tolerance. The stand was measured annually through five growing seasons. The results indicated that the growth difference among the young E. benthamii was noticeable. For example, the maximum and minimum value of five-year old trees at diameter breast height (DBH) was 27.9 centimeters and 1.27 centimeters;and the maximum and minimum value of tree height was 22.86 meters and 2.44 meters, respectively. The yearly change in DBH and height of E. benthamii had significant differences. The average annual survival rates of E. benthamii had differences under the two planting densities (1650 trees ha-1 and 1237 trees ha-1). The densities also had effects on the height and DBH growth of E. benthamii. The average DBH and height of 1650 trees ha-1 plantation were 11.18 centimeters and 15.03 meters, and the average DBH and height of 1237 trees ha-1 plantation were 13.46 centimeters and 16.28 meters. The volume per hectare of 1650 trees ha-1 and 1237 trees ha-1 plantation were 111.45 cubic meters and 101.15 cubic meters, respectively. Average diameter growth was almost 2.54 centimeters per year and average height growth was over 3 meters. E. benthamii plantations were considered tolerant to -7.4 degrees Celsius and a cold spell during early 2014 (-11.3 degrees Celsius for two consecutive nights) killed the plantation. The growth of E. benthamii also varied depending on surrounding conditions. The difference in growth of row seven versus row one was a good example. The reason probably was that row seven was adjacent to a loblolly pine plantation and row one was next to an open field. 展开更多
关键词 EUCALYPTUS benthamii growth Parameters BIOENERGY Cold Tolerance
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Study on the chemical composition of Nauclea officinalis in different months of the same year and different growth years
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作者 Yu-Xin Zhang Ming-Yan Zhou +5 位作者 Zhen-Rui Xie Li Li Xiang-Yi Li Ai-Xia Liu Jun-Qing Zhang Xiao-Liang Li 《Journal of Hainan Medical University》 2021年第12期43-48,共6页
Objective:Based on the quality analysis of Nauclea officinalis in different growth years and different months in the same year,the most suitable harvest year and the specific month in the same year were determined acc... Objective:Based on the quality analysis of Nauclea officinalis in different growth years and different months in the same year,the most suitable harvest year and the specific month in the same year were determined according to the evaluation of the active components in the stem of medicinal parts of Nauclea officinalis.Methods:LC-MS/MS method was used to investigate the quality of Nauclea officinalis from different growth years and different months in the same year,mainly including the content determination of the active ingredients in the medicine.Results:With the prolongation of production life,the content of active ingredients in stem of Nauclea officinalis increased continuously.After reaching a certain number of years,the content of active ingredients increased little;In the middle of the same year,from mid-October to mid-June of the next year,the content of iso-vincin lactam was relatively high,especially between the end of March and the end of May.The content was high and stable,and the highest point was the stem sample collected in May.Conclusion:The content of each component in the stem of Nauclea officinalis with a growth life of more than 5 years has reached a relatively high and stable level.Nauclea officinalis with a growth life of more than 5 years should be collected as raw materials for medicinal materials.The month with high and stable content of isocyanoside lactam,namely May of each year,was taken as the best harvest time of gallbladder in one year.The best harvest time was from mid-October to mid-June of the next year,or from March to May of each year. 展开更多
关键词 Nauclea officinalis Different growth years Different months Active ingredient LC-MS/MS
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基于FP-growth算法的交通事故数据关联规则挖掘研究
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作者 马健 谢雨晴 +2 位作者 张丽岩 王燕 周欢生 《科技创新与生产力》 2024年第9期95-97,共3页
为了探寻多种事故影响因素共同作用下诱发交通事故的某种规律以及各因素间的关系,本文采用FP-growth算法对收集到的交通事故数据进行分析研究,挖掘其中的潜在价值信息,找出事故发生的原因,根据分析结果给相关部门提出建议,帮助城市交通... 为了探寻多种事故影响因素共同作用下诱发交通事故的某种规律以及各因素间的关系,本文采用FP-growth算法对收集到的交通事故数据进行分析研究,挖掘其中的潜在价值信息,找出事故发生的原因,根据分析结果给相关部门提出建议,帮助城市交通管理者制定更有效的管理措施,以达到降低交通事故发生频率的目的。 展开更多
关键词 交通事故 关联规则 FP-growth
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9% Industrial Growth This Year
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《China's Foreign Trade》 2002年第4期57-57,共1页
关键词 WILL Industrial growth This year
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基于FP-growth的老年行人交通事故损伤致因研究
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作者 刘永涛 张慧臣 +3 位作者 袁诗泉 高隆鑫 王鹏 赵晨 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第6期176-182,共7页
为研究老年行人交通事故相关因素及其对损伤程度的影响,以中国交通事故深度调查数据库中2013—2023年710起机动车-老年行人事故为分析对象,利用FP-growth算法挖掘出4类影响因素28个类型变量共5594项关联规则。研究结果表明:行人年龄、... 为研究老年行人交通事故相关因素及其对损伤程度的影响,以中国交通事故深度调查数据库中2013—2023年710起机动车-老年行人事故为分析对象,利用FP-growth算法挖掘出4类影响因素28个类型变量共5594项关联规则。研究结果表明:行人年龄、碰撞速度、事故时间段及事故地点是影响老年行人事故死亡率的显著因素。特别是,行人年龄和碰撞速度对死亡率有显著影响,随着碰撞速度的增加,死亡率显著上升;60岁及以上老年行人年龄每增加1岁,其死亡率提升0.037倍。此外,事故发生在夜间、郊区或村庄的死亡率更高。研究结果可为提高老年行人交通安全,制定相关安全措施提供一定参考。 展开更多
关键词 FP-growth算法 逻辑回归模型 老年行人安全 交通事故数据分析
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比较YEARS评分与简化Wells联合年龄校正D-二聚体评分用于疑似肺栓塞患者的诊断价值
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作者 谭笑 郭燕妮 《临床肺科杂志》 2024年第12期1838-1843,共6页
目的通过前瞻性研究比较YEARS评分与简化Wells联合年龄校正D-二聚体评分(sWells-Age)用于疑似肺栓塞患者的诊断价值。方法纳入2021年3月3日到2022年4月30日于宜宾市第二人民医院就诊且符合纳排标准的可疑肺栓塞病人522名,采用前瞻性观... 目的通过前瞻性研究比较YEARS评分与简化Wells联合年龄校正D-二聚体评分(sWells-Age)用于疑似肺栓塞患者的诊断价值。方法纳入2021年3月3日到2022年4月30日于宜宾市第二人民医院就诊且符合纳排标准的可疑肺栓塞病人522名,采用前瞻性观察研究,由临床医师对照YEARS评分收集患者基线信息,计算患者YEARS评分及sWells-Age评分判断其目前肺栓塞临床可能性。所有排除肺栓塞且未进行抗凝治疗的患者进行3个月随访。以CTPA检查结果作为诊断金标准,分别计算YEARS评分及sWells-Age评分敏感度、特异度、κ值等指标,绘制两者ROC曲线并计算AUC值。结果sWells-Age评分及YEARS评分灵敏度分别为85.71%、93.41%(P<0.001),特异度分别为69.23%、56.92%(P<0.001),AUC值分别为0.775(95%CI 0.688~0.816)、0.752(95%CI 0.711~0.838),与CTPA的κ值分别为0.526、0.465,均>0.410,结果一致性均属于中等,两者灵敏度比较(χ^(2)=5.143,P<0.025),差异具有统计学意义,两者特异度比较(χ^(2)=12.500,P<0.001),差异具有显著统计学意义。结论sWells-Age评分优于YEARS评分,但YEARS评分项目少,灵敏度及安全性高,可应用于早期肺栓塞患者的筛查。 展开更多
关键词 肺栓塞 yearS评分 简化Wells评分 年龄校正 D-二聚体
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基于改进FP-growth算法的食品风险因素关联分析方法
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作者 于家斌 马欣玥 +5 位作者 赵峙尧 王小艺 张新 崔晓玉 白玉廷 陈帅祥 《食品科学》 EI CAS CSCD 北大核心 2024年第23期250-258,共9页
为解决传统食品安全监督抽检“随机抽”模式存在的抽检决策主观性强、靶向性不高的问题,本研究提出一种基于改进Frequent Pattern-growth(FP-growth)算法的食品风险因素关联分析方法。首先,采用熵权法分别对食品种类的风险指标进行权重... 为解决传统食品安全监督抽检“随机抽”模式存在的抽检决策主观性强、靶向性不高的问题,本研究提出一种基于改进Frequent Pattern-growth(FP-growth)算法的食品风险因素关联分析方法。首先,采用熵权法分别对食品种类的风险指标进行权重分配,以计算出不同食品种类的风险指数。其次,以风险指数为特征,基于小批量K均值算法(MiniBatchKmeans)进行风险聚类,得到食品的风险等级。最后,采用带约束的改进FP-growth算法进行食品风险因素关联规则挖掘,挖掘食品风险等级与食品种类、时间、地域属性信息之间的关联关系,并对挖掘出的结果进行关联分析,从而为精准靶向引导抽检决策提供指导。本研究依托2019年中国某些地区的食品抽检数据进行分析,对其进行指标赋权,计算风险指数;后经过风险聚类为低风险、中风险和高风险;最后,将数据导入改进FPgrowth算法,得到食品风险因素关联规则。通过对比实验得到结果:对于17214条抽检数据,本研究提出的改进FP-growth算法相较于Apriori算法运行时间短;相较于传统FP-growth算法,删除了无效规则,提高了对食品风险因素关联规则的分析效率,从而为食品监管部门抽检工作提供了准确、高效的决策依据。 展开更多
关键词 食品安全监督抽检 关联分析 熵权法 MinibatchKmeans聚类 Frequent Pattern-growth算法
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Structural Engineering of Hierarchical Magnetic/Carbon Nanocomposites via In Situ Growth for High-Efficient Electromagnetic Wave Absorption 被引量:3
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作者 Xianyuan Liu Jinman Zhou +1 位作者 Ying Xue Xianyong Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期262-278,共17页
Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant challenges.Developing new materials and innovative stru... Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant challenges.Developing new materials and innovative structural design concepts is crucial for expanding the application field of electromagnetic wave absorption.Particularly,hierarchical structure engineering has emerged as a promising approach to enhance the physical and chemical properties of materials,providing immense potential for creating versatile electromagnetic wave absorption materials.Herein,an exceptional multi-dimensional hierarchical structure was meticulously devised,unleashing the full microwave attenuation capabilities through in situ growth,selfreduction,and multi-heterogeneous interface integration.The hierarchical structure features a three-dimensional carbon framework,where magnetic nanoparticles grow in situ on the carbon skeleton,creating a necklace-like structure.Furthermore,magnetic nanosheets assemble within this framework.Enhanced impedance matching was achieved by precisely adjusting component proportions,and intelligent integration of diverse interfaces bolstered dielectric polarization.The obtain Fe_(3)O_(4)-Fe nanoparticles/carbon nanofibers/Al-Fe_(3)O_(4)-Fe nanosheets composites demonstrated outstanding performance with a minimum reflection loss(RLmin)value of−59.3 dB and an effective absorption bandwidth(RL≤−10 dB)extending up to 5.6 GHz at 2.2 mm.These notable accomplishments offer fresh insights into the precision design of high-efficient electromagnetic wave absorption materials. 展开更多
关键词 Electromagnetic wave absorption Hierarchical structure In situ growth Self-reduction
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Subcutaneous fatty acid composition of steers finished as weanlings or yearlings with and without growth promotants
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作者 Cletos Mapiye Tyler D Turner +3 位作者 John A Basarab Vern S Baron Jennifer L Aalhus Michael ER Dugan 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第1期98-105,共8页
Background: The current study evaluated the subcutaneous fatty acid (FA) composition of calf- and yearling-fed steer with or without growth promoting implants. Crossbred steers (n = 112; 267 ± 5.0 kg) of the... Background: The current study evaluated the subcutaneous fatty acid (FA) composition of calf- and yearling-fed steer with or without growth promoting implants. Crossbred steers (n = 112; 267 ± 5.0 kg) of the same contemporary group were allocated to one of four production system and implant strategy based treatments in a completely randomized design with a 2 × 2 factorial arrangement of treatments. Results: There were no interactions (P 〉 0.05) between production systems and growth promoting implants for the total and individual subcutaneous FA. Yearling as opposed to calf finishing reduced (P 〈 0.05) subcutaneous proportions of C20:3n-6, trans (t)l 2-18:1, C14:0, several minor cis-monounsaturated FA (c-MUFA; c9-14:1, c11-16:1, cl 1-18:1, cl 2-18:1, cl 3-18:1, c9-20:1 and cl 1-20:1), and increased (P 〈 0.05) subcutaneous proportions of tl 1 cl 5-18:2, total and individual branched-chain FA. Subcutaneous fat from steers implanted with growth promotants had higher (P 〈 0.05) proportions of total polyunsaturated FA (PUFA), total n-6 PUFA, C18:2n-6 and individual t-18:1 isomers (t6 to tl0) compared to non-implanted steers. Conclusions: Overall, current findings show that production systems and growth promotants led to only minor differences in subcutaneous FA composition of beef steers. 展开更多
关键词 Age at feedlot entry BEEF Fatty acids growth implant STEERS
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