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The sow vaginal and gut microbiota associated with longevity and reproductive performance 被引量:1
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作者 Ziyu Liu Tsungcheng Tsai +5 位作者 Bin Zuo Samantha Howe Jason EFarrar Christopher ERandolph Charles VMaxwell Jiangchao Zhao 《Journal of Animal Science and Biotechnology》 2025年第2期577-595,共19页
Background Sow longevity and reproductivity are essential in the modern swine industry.Although many studies have focused on the genetic and genomic factors for selection,little is known about the associations between... Background Sow longevity and reproductivity are essential in the modern swine industry.Although many studies have focused on the genetic and genomic factors for selection,little is known about the associations between the microbiome and sows with longevity in reproduction.Results In this study,we collected and sequenced rectal and vaginal swabs from 48 sows,nine of which completed up to four parities(U4P group),exhibiting reproductive longevity.We first identified predictors of sow longevity in the rectum(e.g.,Akkermansia)and vagina(e.g.,Lactobacillus)of the U4P group using RandomForest in the early breeding stage of the first parity.Interestingly,these bacteria in the U4P group showed decreased predicted KEGG gene abundance involved in the biosynthesis of amino acids.Then,we tracked the longitudinal changes of the micro-biome over four parities in the U4P sows.LEfSe analysis revealed parity-associated bacteria that existed in both the rectum and vagina(e.g.,Streptococcus in Parity 1,Lactobacillus in Parity 2,Veillonella in Parity 4).We also identi-fied patterns of bacterial change between the early breeding stage(d 0)and d 110,such as Streptococcus,which was decreased in all four parties.Furthermore,sows in the U4P group with longevity potential also showed better reproductive performance.Finally,we discovered bacterial predictors(e.g.,Prevotellaceae NK3B31 group)for the total number of piglets born throughout the four parities in both the rectum and vagina.Conclusions This study highlights how the rectal and vaginal microbiome in sows with longevity in reproduc-tion changes within four parities.The identification of parity-associated,pregnancy-related,and reproductive performance-correlated bacteria provides the foundation for targeted microbiome modulation to improve animal production. 展开更多
关键词 longevity Parity Rectal microbiome Reproductive performance SOWS Vaginal microbiome
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Introduction to Longevity Counties in China
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作者 Qi-feng Tang Xin-lu Cui +1 位作者 Si-wen Liu Da-wen Liu 《China Geology》 2025年第3期631-634,共4页
Since ancient times,humanity has yearned for longevity,viewing health and long life as enduring aspirations.Research has shown that longevity genes may be passed down through certain populations(Costa D,2019).However,... Since ancient times,humanity has yearned for longevity,viewing health and long life as enduring aspirations.Research has shown that longevity genes may be passed down through certain populations(Costa D,2019).However,genetics alone is not the decisive factor-environmental conditions also play a vital role in achieving a long life(Selinus O,2013). 展开更多
关键词 health long life longevity genes china longevity counties ancient times environmental conditions GENETICS
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Longevity prediction and missing data treatment of landslide dams
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作者 WANG Danyan YANG Xingguo +2 位作者 ZHOU Jiawen FENG Zhenyu LIAO Haimei 《Journal of Mountain Science》 2025年第7期2640-2653,共14页
Landslide dam failures can cause significant damage to both society and ecosystems.Predicting the failure of these dams in advance enables early preventive measures,thereby minimizing potential harm.This paper aims to... Landslide dam failures can cause significant damage to both society and ecosystems.Predicting the failure of these dams in advance enables early preventive measures,thereby minimizing potential harm.This paper aims to propose a fast and accurate model for predicting the longevity of landslide dams while also addressing the issue of missing data.Given the wide variation in the survival times of landslide dams—from mere minutes to several thousand years—predicting their longevity presents a considerable challenge.The study develops predictive models by considering key factors such as dam geometry,hydrodynamic conditions,materials,and triggering parameters.A dataset of 1045 landslide dam cases is analyzed,categorizing their longevity into three distinct groups:C1(<1 month),C2(1 month to 1 year),and C3(>1 year).Multiple imputation and knearest neighbor algorithms are used to handle missing data on geometric size,hydrodynamic conditions,materials,and triggers.Based on the imputed data,two predictive models are developed:a classification model for dam longevity categories and a regression model for precise longevity predictions.The classification model achieves an accuracy of 88.38%while the regression model outperforms existing models with an R^(2) value of 0.966.Two real-life landslide dam cases are used to validate the models,which show correct classification and small prediction errors.The longevity of landslide dams is jointly influenced by factors such as geometric size,hydrodynamic conditions,materials,and triggering events.Among these,geometric size has the greatest impact,followed by hydrodynamic conditions,materials,and triggers,as confirmed by variable importance in the model development. 展开更多
关键词 CATEGORY longevity range IMPUTATION Prediction models Decision Tree
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Introduction to the Bama renowned longevity county in the Guangxi Zhuang Autonomous Region
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作者 Qi-feng Tang Lu-dan Zhang 《China Geology》 2025年第3期635-638,共4页
Guangxi Zhuang Autonomous Region is one of the most densely clustered regions of“Longevity County”in China,and Bama County is a typical representative of mountainous and hilly longevity villages in the country.In re... Guangxi Zhuang Autonomous Region is one of the most densely clustered regions of“Longevity County”in China,and Bama County is a typical representative of mountainous and hilly longevity villages in the country.In recent years,the local government and residents have actively embraced the United Nations Sustainable Development Goals(SDGs)and the Healthy China Initiative,striving to implement the scientific principle that“lucid waters and lush mountains are invaluable assets.” 展开更多
关键词 United Nations Sustainable Development Goals Bama County Guangxi Zhuang Autonomous Region longevity sustainable development goals sdgs lucid waters lush mountains Healthy China Initiative
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The Artistic Innovation of the Longevity Preface by Gui Youguang
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作者 HUI Chen 《Cultural and Religious Studies》 2025年第5期242-245,共4页
The object of study selected for this paper is the Longevity Preface of the more controversially evaluated and less studied ancient writings of Qui Youguang.These essays are also the most included in the collection of... The object of study selected for this paper is the Longevity Preface of the more controversially evaluated and less studied ancient writings of Qui Youguang.These essays are also the most included in the collection of Qui Youguang’s writings,with differentiated content tendencies and a gradual convergence in the genre’s style.The artistic value embedded in the creation of Longevity Preface is rich in research value.The topic of this study is to analyze the innovations in the artistic characteristics of Longevity Preface by focusing on the specific breakthroughs in the image of the preface master,the expression of values,and the stylistic paradigm of Longevity Preface,so as to examine the contribution of Longevity Preface in the development of the genre. 展开更多
关键词 Gui Youguang longevity Preface artistic features
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人类长寿的机制与长寿医学
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作者 何琪杨 《中国生物化学与分子生物学报》 北大核心 2026年第1期3-10,共8页
在积极应对人口老龄化的挑战中,从健康老龄化典范的百岁老人入手,深入研究长寿机制,无论是改善晚年健康、还是减轻经济负担,均具有重大的理论和实际意义。百岁老人表现为患慢性病少和健康韧性强,其机制与长寿基因、性别、心理、肠道菌... 在积极应对人口老龄化的挑战中,从健康老龄化典范的百岁老人入手,深入研究长寿机制,无论是改善晚年健康、还是减轻经济负担,均具有重大的理论和实际意义。百岁老人表现为患慢性病少和健康韧性强,其机制与长寿基因、性别、心理、肠道菌群、经济状况和生活环境等相关。本文还对人类个体极限寿命进行了探讨,强调基于科学证据的寿命极限115岁的可靠性。长寿机制与长寿基因密切相关,要活到百岁,基因起决定性的作用。长寿机制研究成果应用的场景是长寿诊所,长寿医学是研究如何延长健康寿命的新学科。本文对长寿医学的发展前景进行了探讨。 展开更多
关键词 长寿机制 百岁老人 寿命极限 长寿医学 长寿干预 健康韧性
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长寿抗衰干预:基于衰老机制的应用前景
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作者 何琪杨 《中国生物化学与分子生物学报》 北大核心 2026年第1期1-2,共2页
衰老机制的研究成果,在人体应用中有2种学科途径:老年医学和长寿医学。经过多年的研究,靶向衰老细胞的衰老干预研究,在小鼠体内取得良好的结果,但转化到人体效果有限。本专题对相关的研究,从不同角度进行了综述和总结,展示了人体应用的... 衰老机制的研究成果,在人体应用中有2种学科途径:老年医学和长寿医学。经过多年的研究,靶向衰老细胞的衰老干预研究,在小鼠体内取得良好的结果,但转化到人体效果有限。本专题对相关的研究,从不同角度进行了综述和总结,展示了人体应用的前景。在未来的研究中,可能需要回答衰老机制的一些基本问题,尤其是人体老年期的衰老细胞的动态和数量变化,从而为临床应用奠定坚实的理论基础。 展开更多
关键词 衰老机制 老年科学 长寿抗衰 转化应用
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Genes required for the functions of olfactory AWA neuron regulate the longevity of Caenorhabditis elegans in an insulin/IGF signaling-dependent fashion
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作者 沈露露 杜敏 +2 位作者 林兴凤 蔡婷 王大勇 《Neuroscience Bulletin》 SCIE CAS CSCD 2010年第2期91-103,共13页
Objective To investigate the interaction between the genes required for the functions of AWA olfactory neuron and insulin/IGF signaling in regulating the longevity of nematode Caenorhabditis elegans (C. elegans). Me... Objective To investigate the interaction between the genes required for the functions of AWA olfactory neuron and insulin/IGF signaling in regulating the longevity of nematode Caenorhabditis elegans (C. elegans). Methods The mutants that had loss-of-function mutation of the genes required for AWA, AWC, ASE, and AFD sensory neurons were employed. Lifespan, the speed of pharynx pumping, the intestinal autofluorescence, the dauer formation, and the brood size were examined. Rescue experiments were performed to confrm the role of the genes required for the functions of AWA neuron in regulating lifespan. Moreover, genetic interactions between genes required for the functions of AWA neuron and insulin/ IGF signaling were investigated. Results Mutations of odr-7, odr-2, and odr-3 genes required for the functions of AWA neuron significantly increased the mean lifespan of nematodes and slowed the accumulation of intestinal autofluorescence. Besides, these mutations were closely associated with higher pumping rates during aging. However, mutation of odr-7, odr- 2, or odr-3 did not obviously affect the brood size or the dauer formation, and the regulation of longevity by odr-7, odr-2, and odr-3 was temperature-independent. In contrast, mutations of genes required for the functions of ASE, AWC, and AFD sensory neurons did not infuence the nematode lifespan. Moreover, expression of odr-7, odr-2 and odr-3 in AWA neuron could completely or largely restore the altered lifespan in odr-7, odr-2 and odr-3 mutants. Furthermore, genetic interaction assay demonstrated that the extended lifespan in odr-7 mutant could be suppressed by daf-16 mutation and enhanced by daf- 2 or age-1 mutation, whereas mev-1 and pha-4 were not required for the long lifespan of odr-7 mutant. Conclusion The genes required for the function of AWA sensory neuron could regulate the nematode longevity in an insulin/IGF signaling-dependent fashion in C. elegans. 展开更多
关键词 longevity ODR-7 AWA olfactory neuron insulin/IGF signaling genetic interaction C. elegans
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Improving Linear Type Traits to Improve Production Sustainability and Longevity in Purebred Sahiwal Cattle
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作者 Ashutosh Dubey Sharad Mishra Vikas Khune Pavan K. Gupta Bhooshan K. Sahu Arvind K. Nandanwar 《Journal of Agricultural Science and Technology(A)》 2012年第5期636-639,共4页
In order to determine various traits which need to be improved for improving the productive life span and longevity, purebred Sahiwal cows available at bull mother experimental farm and cattle breeding farm located at... In order to determine various traits which need to be improved for improving the productive life span and longevity, purebred Sahiwal cows available at bull mother experimental farm and cattle breeding farm located at Veterinary College, Durg, Chhattisgarh, India were used. For present investigation, 17 linear type traits were measured, scaled and scored as per the guidelines of International Committee for Animal Recording (2001). The average score point (ASP) under 1-9 point scale score system along with respective observed group for different linear type traits were stature (6.88; taller), chest width (5.30; intermediate), body depth (4.11; intermediate), rump angle (4.27; intermediate), rump width (5.09; intermediate), rear leg set-side view (4.55; intermediate), rear leg set-rear view (5.95; intermediate), foot angle (5.66; intermediate), udder depth (5.71; intermediate), rear udder height (4.90; intermediate), udder balance (5.27; intermediate), udder cleft (3.75; intermediate), fore udder attachment (5.55; intermediate), teat length (3.54; intermediate), fore teat placement (5.33; intermediate), rear teat placement (6.37; intermediate) and teat thickness (2.76; narrow). For most of the traits, ASP which lies near midpoint (i.e. near five) is known to be ideal for dairy type cattle. Moreover, some traits also showed the presence of undesirable ASP. Hence, the traits such as body depth, rump angle, foot angle, udder depth, rear udder height, udder cleft, fore udder attachment, teat length, and teat thickness needs to be improved for improving the production sustainability and herd life of Sahiwal cattle. Thus, present investigation gives explicit clue to incorporate these conformation traits in selection program of this valuable germplasm commonly found in Southern part of Asia (India, Pakistan, Srilanka, etc.). 展开更多
关键词 SAHIWAL linear type traits production sustainability and longevity.
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古树长寿机制研究进展
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作者 闵张翔 陈一锋 +2 位作者 陈志伟 郑炳松 闫道良 《浙江林业科技》 2026年第1期107-114,共8页
古树是植物界中具有独特生态和文化意义的稀有资源,其长寿现象是植物对长期演化与环境适应的重要结果。对古树长寿的研究有助于深入解析植物长寿的生物学机制,为古树保护和生态系统管理提供科学依据,并且对历史文化遗产的传承也大有裨... 古树是植物界中具有独特生态和文化意义的稀有资源,其长寿现象是植物对长期演化与环境适应的重要结果。对古树长寿的研究有助于深入解析植物长寿的生物学机制,为古树保护和生态系统管理提供科学依据,并且对历史文化遗产的传承也大有裨益。本文从古树长寿的社会因素、自然因素、生理特性和遗传特性四个维度综述了古树长寿的研究进展,旨在从多维度多角度多学科来解析古树长寿的原因,为古树的保护和植物长寿机制研究提供有价值的参考。 展开更多
关键词 古树长寿 生理特性 遗传特性 古树文化价值
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Study on the Rapid Method to Predict Longevity of Controlled Release Fertilizer Coated by Water Soluble Resin 被引量:11
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作者 DAI Jian-jun FAN Xiao-lin +2 位作者 YU Jian-gang LIU Fang ZHANG Qiao 《Agricultural Sciences in China》 CAS CSCD 2008年第9期1127-1132,共6页
The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dis... The study discussed the rapid method to test and predict the longevity of controlled release fertilizers (CRFs) coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method. 展开更多
关键词 controlled release fertilizer (CRF) water soluble resin coating longevity of CRF rapid test method
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Effects of back fat,growth rate,and age at first mating on Yorkshire and Landrace sow longevity in China 被引量:6
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作者 HU Bin MO De-lin +2 位作者 WANG Xiao-ying LIU Xiao-hong CHEN Yao-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第12期2809-2818,共10页
In the present study, genetic parameters for longevity and genetic correlations with back fat (BF), average daily gain (ADG), and first mating age (FMA) were estimated from 19 300 Yorkshire and 18 378 Landrace s... In the present study, genetic parameters for longevity and genetic correlations with back fat (BF), average daily gain (ADG), and first mating age (FMA) were estimated from 19 300 Yorkshire and 18 378 Landrace sows from 12 farms derived from one breeding system. General linear models (GLM) were employed to estimate genetic correlations with heritability (h2). Longevity was defined by six different parameters (i.e., traits) and heritability ranged from h2=0.13 to 0.16 (P〈0.05) in both swine breeds. Genetic correlations between different longevity definitions were positive and high (r=0.79 to 0.99; P〈0.05). BF exhibited low positive genetic correlations (r=0.12 to 0.15; P〈0.05) with longevity traits identified in both pig breeds which were dependent on trait definition, whereas ADG and FMA showed weak negative genetic correlations with longevity traits. The influence of BF, ADG, and FMA on longevity traits was examined by dividing the production and reproductive traits into several numerical groups; the influence of each longevity trait was subsequently analyzed among the different groups. The results indicated BF was the best trait to improve longevity among BF, ADG, and FMA, which showed positive effects for almost all longevity traits. For Yorkshire sows, gilts with over 18 mm BF were most desirable; Landrace with 10.6-13 mm BF were suitable for longevity. ADG was not favorable for gilt selection, because the correlation between growth rate and longevity very low. For FMA, our results indicated gilts mating before 230 days exhibited a longer life span. Therefore, we suggest farmers should select for thicker back fat and mate at an earlier age to improve sow longevity. 展开更多
关键词 SOW longevity back fat average daily gain first mating age
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Association between FOXO3A gene polymorphisms and human longevity: a meta-analysis 被引量:3
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作者 Ji-Ming Bao Xian-Lu Song +6 位作者 Ying-Qia Hong Hai-Li Zhu Cui Li Tao Zhang Wei Chen Shan-Chao Zhao Qing Chen 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第3期446-452,共7页
Numerous studies have shown associations between the FOXO3A gene, encoding the forkhead box 03 transcription factor, and human or specifically male longevity. However, the associations of specific FOXO3A polymorphisms... Numerous studies have shown associations between the FOXO3A gene, encoding the forkhead box 03 transcription factor, and human or specifically male longevity. However, the associations of specific FOXO3A polymorphisms with longevity remain inconclusive. We performed a meta-analysis of existing studies to clarify these potential associations. A comprehensive search was conducted to identify studies of FOXO3A gene polymorphisms and longevity. Pooled odds ratios (ORs) and 95% confidence intervals (Cls) were calculated by comparing the minor and major alleles. A total of seven articles reporting associations of FOXO3A polymorphisms with longevity were identified and included in this meta-analysis. These comprised 11 independent studies with 5241 cases and 5724 controls from different ethnic groups, rs2802292, rs2764264, rs13217795, rs1935949 and rs2802288 polymorphisms were associated with human longevity (OR = 1.36, 95% Cl = 1.10-1.69, P= 0.005; OR = 1.20, 95% CI = 1.04-1.37, P= 0.01; OR = 1.27, 95% CI = 1.10-1.46, P= 0.001; OR = 1.14, 95% CI = 1.01-1.27 and OR = 1.24, 95% CI = 1.07-1.43, P= 0.003, respectively). Analysis stratified by gender indicated significant associations between rs2802292, rs2764264 and rs13217795 and male longevity (OR = 1.54, 95% Cl = 1.33-1.79, P〈 0.001; OR = 1.38, 95% Cl = 1,15-1.66, P= 0.001; and OR = 1.39, 95% Cl = 1.15-1.67, P= 0.001), but rs2802292, rs2764264 and rs1935949 were not linked to female longevity. Moreover, our study showed no association between rs2153960, rs7762395 or rs13220810 polymorphisms and longevity. In conclusion, this meta-analysis indicates a significant association of five FOXO3A gene polymorphisms with longevity, with the effects of rs2802292 and rs2764264 being male-specific, Further investigations are required to confirm these findings. 展开更多
关键词 FOXO3A longevity META-ANALYSIS POLYMORPHISM
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Role of insulin/insulin-like growth factor 1 signaling pathway in longevity 被引量:2
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作者 Chun-LeiCheng Tian-QinGao +1 位作者 ZhenWang Dian-DongLi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第13期1891-1895,共5页
The insulin/insulin-like growth factor 1 (IGF-1) signaling pathway is evolutionary conserved in diverse speciesincluding C.elegans, saccharomyces cerevisiae, Drosophila melanogaster, rodents and humans, which is invol... The insulin/insulin-like growth factor 1 (IGF-1) signaling pathway is evolutionary conserved in diverse speciesincluding C.elegans, saccharomyces cerevisiae, Drosophila melanogaster, rodents and humans, which is involved in many interrelated functions that are necessary for metabolism, growth and reproduction. Interestingly, more and more research has revealed that insulin/IGF-1 signaling pathway plays a pivotal role in the regulation of longevity. Generally, disruption of the power of this pathway will extend longevity in species ranging from C.elegansto humans. The role of insulin/IGF-1 in longevit yis probably related to stress resistance. Although the underlying mechanisms of longevity are not fully understood, the Insulin/IGF-1 signaling pathway has attracted substantial attention and it will be a novel target to prevent or postpone age-related diseases and extend life span. In this review, we mainly focus on the similar constitution and role of insulin/IGF-1 signaling pathway in C.elegans, saccharomyces cerevisiae, rodents and humans. 展开更多
关键词 INSULIN Insulin-like growth factor 1 longevity Caloric restricted
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Relationship between food polyamines and gross domestic product in association with longevity in Asian countries 被引量:3
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作者 Phan Nguyen Thanh Binh Kuniyasu Soda +1 位作者 Chizuko Maruyama Masanobu Kawakami 《Health》 2010年第12期1390-1396,共7页
The relationship between gross domestic pro- duct (GDP) and dietary profile, with a focus on polyamine intake, was investigated in 35 Asian countries. Data on food supply, GDP, and health condition were collected from... The relationship between gross domestic pro- duct (GDP) and dietary profile, with a focus on polyamine intake, was investigated in 35 Asian countries. Data on food supply, GDP, and health condition were collected from databases of the United Nations, the International Monetary Fund, and the World Health Organization, respectively. The amount of polyamine intake from food was estimated using polyamine concentrations listed in published sources. The amounts of putrescine, spermidine, spermine, and total polyamines in 1000 kcal of food in Asian countries were 39.07 ± 17.98, 33.74 ± 14.35, 14.05 ± 6.60 and 86.85 ± 33.96 μmol/1000 kcal, respectively. Putrescine, spermidine, and spermine constituted 44, 39, and 17% of total polyamine, respectively. Vegetables contributed the largest amount of both putrescine and spermidine and the second largest amount of spermine (45.5%, 62.2% and 27.2% of total putrescine, spermidine, and spermine, respectively). Meat was the richest source of spermine and contributed the greatest amount (50%) of this polyamine. We showed a significant positive association between GDP and the amount of polyamine per 1000 kcal of food. Lifespan was associated with both GDP and the amount of polyamine per energy quotient of food. As several basic research studies have shown that polyamines help prolong longevity, it follows that polyamines may have a role in determining the lifespan of humans. 展开更多
关键词 POLYAMINE GDP longevity CARDIOVASCULAR DISEASES FOOD
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Longevity,Capital Formation and Economic Development 被引量:1
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作者 Zhang Qiong 《Chinese Journal of Population,Resources and Environment》 2012年第1期53-63,共11页
Many researchers have concluded that longer life expectancies prompt increased investment in education,as a prolonged labor supply raises the rate of return on education.Besides explaining the empirical evidence behin... Many researchers have concluded that longer life expectancies prompt increased investment in education,as a prolonged labor supply raises the rate of return on education.Besides explaining the empirical evidence behind this conclusion(at an absolute level),there is another issue to be discussed:does time spent studying and working increase proportionally with higher longevity?Building on an extended life-cycle model,this paper shows that prolonged life expectancy will cause individuals to increase their time in education but may not warrant rises in labor input.Later we show that higher improvement rate of longevity rather than initial life expectancy will promote economic growth,even we exclude the mechanism of human capital formation,and only consider growth effects of higher improvement rate of life expectancy from physical capital investment. 展开更多
关键词 longevity EDUCATION labor supply economic development
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Negative Association between Seed Dormancy and Seed Longevity in Bread Wheat 被引量:1
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作者 Jing Zhang Shijie Xiang Hongshen Wan 《American Journal of Plant Sciences》 2021年第3期347-365,共19页
Many organisms have dormant stages with an extension of their life span to increase longevity, and deeper dormancy is usually related to greater longevity. In cereal crops, seed dormancy is significantly associated wi... Many organisms have dormant stages with an extension of their life span to increase longevity, and deeper dormancy is usually related to greater longevity. In cereal crops, seed dormancy is significantly associated with pre-harvest sprouting tolerance during seed development, as seed longevity is a valuable trait for seed banks and providing reliable crop seeds to farmers. In this study, we evaluated both seed dormancy and longevity in bread wheat based on germination and artificial aging tests. According to phenotypic clustering analysis, relative germination rate/potential and relative seedling vigor index were more effective to indicate seed longevity than relative electrical conductivity in wheat, while all the four investigated phenotypes of relative germination potential, relative germination rate, germination index and degree of seed dormancy fit well as a reflex of wheat seed dormancy. In the correlation analysis, the germination level of newly harvested grain negatively reflected its degree of seed dormancy, while the germination ability of grain after artificial aging reflected its seed longevity. However, in contrast to the current opinion in plant, seed dormancy was significantly negatively correlated to seed longevity in our study, and it was not an accidental phenomenon, for that the majority of accessions with high degree of seed dormancy had short seed longevity. To our knowledge, this is the first to report the negative association between seed dormancy and longevity in cereal crops. It would lead to further concerns about how to breed wheat with both prolonged seed longevity and deep dormancy to avoid pre-harvest sprouting. 展开更多
关键词 Wheat Seed Germination Test Artificial Aging longevity and Dormancy Negative Relationship
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Effects of Temperature, Relative Humidity and Moisture Content on Seed Longevity of Shrubby Russian Thistle ( Salsola vermiculata L,) 被引量:1
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作者 Abdoul Aziz Niane Paul Christiaan Struik Zewdie Bishaw 《Journal of Agricultural Science and Technology(B)》 2013年第9期623-634,共12页
Salsola vermiculata is a highly palatable shrub and widely used in rangeland rehabilitation programs, but has short seed longevity. To identify the most cost effective storage method for S. vermiculata, experiments we... Salsola vermiculata is a highly palatable shrub and widely used in rangeland rehabilitation programs, but has short seed longevity. To identify the most cost effective storage method for S. vermiculata, experiments were carried out to test the effects of fruit bracts (wings), temperature regimes, seed moisture and packaging methods on storage life. Seed samples were removed from storage at monthly intervals for testing and towards the end of the experiments samples were transferred from hermetic to ambient storage conditions and tested for germination. Experiment 1 continued for 1,140 days, Experiment 2 for 720 days. For de-winged seed, high moisture content increased seed longevity, suggesting that desiccation susceptibility is one of the causes of limited longevity in this species. Most longevity regression lines of winged seeds had negative intercepts suggesting increase in germination resulting from gradual dormancy-breaking. Drying and packaging alone increased longevity by 7.6 and 3.8 times in Experiments 1 and 2, respectively. Samples kept at lower temperature and lower moisture treatments survived longer under ambient conditions. Increased longevity by drying and vacuum packaging alone can provide simple, cost effective and environmentally friendly options for rangeland rehabilitation programs. 展开更多
关键词 Salsola vermiculata L. seed storage vacuum packaging seed longevity probit analysis.
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