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Landscape Aesthetic Characteristics of Wulingyuan World Natural Heritage Property and Realization Path of Aesthetic Education Value
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作者 LUO Shui XIAO Hua XIAO Shizhen 《Journal of Landscape Research》 2023年第5期79-84,88,共7页
Wulingyuan is a world natural heritage property mainly dominated by rare quartz sandstone peak forest landscape at home and abroad and supplemented by karst landscapes,with a large number of geological and historical ... Wulingyuan is a world natural heritage property mainly dominated by rare quartz sandstone peak forest landscape at home and abroad and supplemented by karst landscapes,with a large number of geological and historical sites,biological and ecological landscape and unique cultural landscapes.Preserving the secluded and beautiful scenery environment,biological environment and ecosystem of subtropical zone,Wulingyuan presents a splendid and magnificent landscape,with high aesthetic value,and becomes an important practice base of aesthetic education.The aesthetic education value of Wulingyuan World Natural Heritage Property can be realized by systematically studying and presenting the aesthetic education value of Wulingyuan World Natural Heritage Property,developing a series of aesthetic education courses to lead tourists into the world of Wulingyuan aesthetic education,carrying out a series of popular science activities of“Wulingyuan World Natural Heritage Property Entering Campus”,and incorporating into the aesthetic education curriculum system of schools,etc.This paper analyzes the landscape aesthetic characteristics of Wulingyuan World Natural Heritage Property thoroughly,which indicates the direction for realizing the aesthetic education value of the property,and also provides a reference for realizing the aesthetic education value of similar world natural heritage property. 展开更多
关键词 World natural heritage property Landscape aesthetic characteristics Aesthetic education value Realization path Wulingyuan
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Evaluation of Wildlife Resource Value in Jinggangshan Nature Reserve by CVM
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作者 胡小波 王伟峰 +2 位作者 余本锋 龚慧敏 汪峻 《Journal of Landscape Research》 2010年第5期35-38,共4页
By using Contingent Value Method(CVM),WTP(Willingness to Pay) of wildlife in Jinggangshan Nature Reserve was studied,the overall existence value of wildlife resource(namely the sum of economic,social,ecological value ... By using Contingent Value Method(CVM),WTP(Willingness to Pay) of wildlife in Jinggangshan Nature Reserve was studied,the overall existence value of wildlife resource(namely the sum of economic,social,ecological value added on its existence value) in this area was calculated,and the statistics of primary social and economic factors affecting payment value were analyzed.600 questionnaires had been issued altogether and the recovery rate was 100%,583 of which were valid and the effective rate was 94.2 % which demonstrated that feedback sample quantity had reached the analysis requirement.The study result showed that interviewees with different social characteristics widely dispersed,which complied with the survey principle of random sampling;that the distribution curve of WTP was neither smooth nor normal and as 50 Yuan was frequently-used amount in their daily consumption,people tended to choose this option subconsciously;that WTP had notable correlation with education degree,monthly income and cognition degree,and had relation with age but no obvious relation with gender;that annual payment value per capita was within the research scope of wildlife payment value,that is 40-575 Yuan/(person·year).The final conclusion was that wildlife resource value in this area was 17 845 000 Yuan/year,which was of great significance to the protection of biological diversity and the formulation of corresponding protective measures in Jinggangshan Nature Reserve and even in the whole society. 展开更多
关键词 CONTINGENT value method(CVM) Jinggangshan nature REsERVE WILDLIFE value EvaluATION
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Estimation on Aesthetic Value of Tourist Landscapes in a Natural Heritage Site:Kanas National Nature Reserve,Xinjiang,China 被引量:11
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作者 DI Feng YANG Zhaoping +2 位作者 LIU Xuling WU Jingrui MA Zhongguo 《Chinese Geographical Science》 SCIE CSCD 2010年第1期59-65,共7页
Most world natural heritage sites are designated partly by reason of their prominent aesthetic values in accordance with Article Ⅶ of World Natural Heritage Convention.In this paper, the aesthetic values of Kanas Nat... Most world natural heritage sites are designated partly by reason of their prominent aesthetic values in accordance with Article Ⅶ of World Natural Heritage Convention.In this paper, the aesthetic values of Kanas National Nature Reserve, which has potential for such designation, was analyzed quantitatively using scenic beauty estimation(SBE).The landscapes of 19 representative scenic spots in the Kanas National Nature Reserve in summer and autumn were selected as the objects of evaluation.The contributions of different landscape factors to the aesthetic value of the Kanas National Nature Reserve were revealed using a multivariate quantitative model.The main factors affecting the aesthetic value were waterscapes, vegetation, mountains, folk culture and the tourist environment.The t-test and F-test results are extremely significant.According to the results, some suggestions were given for conserving the landscapes in the Kanas National Nature Reserve. 展开更多
关键词 Kanas National nature Reserve aesthetic value scenic beauty estimation World natural Heritage Xinjiang
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Economic Value Evaluation of Wetland Service in Yeyahu Wetland Nature Reserve,Beijing 被引量:9
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作者 ZHU Lin CHEN Yun +3 位作者 GONG Huili JIANG Weiguo ZHAO Wenji XIAO Yanfang 《Chinese Geographical Science》 SCIE CSCD 2011年第6期744-752,共9页
Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-... Based on multi-source data,this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve,Beijing,China.The ecological services of wetland included gas regulation,water quality im-provement,biodiversity maintenance,erosion control,water supply,recreational opportunity,raw material supply and existence value.Multiple conventional evaluation methods were used to calculate the value of eight wetland services.The results showed that significant values came from biodiversity maintenance and recreational opportunity.The main reasons were as follows.Firstly,Yeyahu Wetland Nature Reserve was the habitat for migrant birds,and government had payed more efforts to protect precious birds.Secondly,the population is large in Beijing.People enjoyed going outside and enjoyed the natural and artificial wetland scenes.At the same time,most people were prepared to pay for wetland conservation.The decline of vegetation cover made the economic value of erosion control the lowest.While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower.The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision. 展开更多
关键词 economic value evaluation wetland service Yeyahu Wetland nature Reserve BEIJING
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The Function and Value of Water Conservation of Forest Ecosystem in Gongbo Nature Reserve of Tibet 被引量:4
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作者 TANG Jia, FANG Jiang-ping, LI Ping, GUO Jian-bin, LU Jie, YUAN Qing-juan Tibet Agriculture and Animal Husbandry College, Nyingchi 860000, China 《Asian Agricultural Research》 2012年第1期68-70,共3页
Gongbo Nature Reserve, located in Nyingchi of Tibet, is by far the largest construction project of forest reserves that China approves and invests in. This article adopts the shadow project method, and estimates the w... Gongbo Nature Reserve, located in Nyingchi of Tibet, is by far the largest construction project of forest reserves that China approves and invests in. This article adopts the shadow project method, and estimates the water conservation function of forest ecosystem of Gongbo Nature Reserve based on the Specifications for Assessment of Forest Ecosystem Services in China promulgated by State Forestry Administration of China. The results show that the total value of water conservation of forest ecosystem in Gongbo Nature Reserve is 8.485 billion yuan, while the function of water conservation is a small fraction of ecological service function, indicating that there is great ecological value in service function of forest ecosystem in Gongbo Nature Reserve, that is, Gongbo Nature Reserve has vital ecological value. 展开更多
关键词 Water CONsERVATION value EsTIMATE Gongbo nature Re
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Non-use value assessment for wetland ecosystem service of Hongxing National Nature Reserve in northeast China 被引量:1
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作者 Xin Jin Jianzhang Ma +1 位作者 Tijiu Cai Xiaoxin Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第6期1435-1442,共8页
By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve (HNNR) in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing... By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve (HNNR) in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing to pay (WTP) for protection of HNNR was 63 %. The WTP ratio was affected by geographical area, contact nature, personal preferences, and familiar degree of the respondents. The WTP value was affected by age, education level and career of the respondents. The mainly reasons for people rejecting to pay for protecting HNNR were "I am not familiar to HNNR" and "I had no capacity for additional spending because of low income". Weighted average individual WTP value was CNY 59.26 Yuan ind.^-1 year^-1 for all the respondents with WTP. The total non-use ecosystem service value of HNNR was CNY 1430 million Yuan in 2013. The heritage value was highest followed by existence value and option value. From the high ecosystem service value in HNNR, it is very important to construct nature reserve for protecting natural ecosystems and human sustainable use of natural resources. 展开更多
关键词 Ecosystem service Non-use value Hongxing National nature Reserve - Xiaoxing'an Mountains
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Change of Forest Ecosystem Service Function and Its Value in Kanas Nature Reserve
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作者 BAI Zhiqiang WANG Wendong +3 位作者 LI Huan LIU Duan GUO Zhongjun LIU Hua 《Journal of Landscape Research》 2019年第6期80-83,共4页
In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated... In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated by using the method of Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008). The results showed that in 2014, the total value of forest ecosystem service function in Kanas Nature Reserve increased by 7.34% compared with that in 2009, and the value of water conservation and biodiversity accounted for the largest proportion. The increasing rate of functional value of shrub forest land was obviously higher than that of coniferous forest land and broad-leaf forest land. The service function and value of different forest types were obviously different. 展开更多
关键词 FOREsT ECOsYsTEM service FUNCTION value assessment KANAs nature REsERVE
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ASSESSMENT OF INDIRECT USE VALUES OF FOREST BIODIVERSITY IN YAOLUOPING NATIONAL NATURE RESERVE, ANHUI PROVINCE
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作者 XUHui QIANYi +1 位作者 ZHENGLin PENGBu-zhuo 《Chinese Geographical Science》 SCIE CSCD 2003年第3期277-283,共7页
Direct use values of forest ecosystem have been recognized apparently due toits easy and convenient assessment, while indirect use values are usually neglected because they arenot easy to be recognized by the public. ... Direct use values of forest ecosystem have been recognized apparently due toits easy and convenient assessment, while indirect use values are usually neglected because they arenot easy to be recognized by the public. For a nature reserve with forest ecosystem, the mostimportant economic values are the indirect use values, which provide human beings and other livingthings with beneficial services through ecological processes and functions. In this case study, aquantifying framework to estimate the annual indirect use values of forest ecosystem has beenestablished in Yaoluoping National Nature Reserve based on alternative cost method and opportunitycost method. The ecological functions assessed in the study relate to six aspects: soil protection,water conservation, CO_2 fixation, nutrient cycling, pollutant decomposition and disease and pestcontrol. These ecological functions provide an economic value of 86.1xl0~6 yuan (RMB) per year(US$10.37xl0~6), which is 25 times higher than the opportunity cost for regular timber production.This study can contribute to the monetary assessment of indirect use values of forest biodiversityand to the conservation and sustainable use of nature reserves. 展开更多
关键词 yaoluoping national nature reserve forest ecosystem ecological functions indirect use value
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Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents 被引量:1
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作者 Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-Reyes 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期846-854,共9页
Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinester... Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes. 展开更多
关键词 Alzheimer’s disease EPIGENETICs genes METHYLATION natural products
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On the Ancient Educational Thought under the Opposite View of Human Nature of the Pre-Qin Scholars--On its Value to Contemporary Higher Education
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作者 Zhichao Zhao 《Journal of Contemporary Educational Research》 2020年第4期52-55,共4页
The pre-qin Scholars’views on human nature could be divided into two types:malleable human nature and immalleable human nature.Based on the theory of the malleability of human nature,Confucianism formed an educationa... The pre-qin Scholars’views on human nature could be divided into two types:malleable human nature and immalleable human nature.Based on the theory of the malleability of human nature,Confucianism formed an educational concept aiming at shaping the ideal personality of Confucianism.The theory of immutability of human nature has become the root of the two distinct educational concepts of Taoism,which advocates letting nature take its course,and Taoism,which aims at reforming human behavior.Either idea has its reasonableness.All of these have a very important impact on our higher education today. 展开更多
关键词 The Pre-Qin scholars Human nature Contemporary value
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Natural Numbers and the Strong Goldbach Conjecture
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第9期3208-3236,共29页
This study introduces the representation of natural number sets as row vectors and pretends to offer a new perspective on the strong Goldbach conjecture. The natural numbers are restructured and expanded with the incl... This study introduces the representation of natural number sets as row vectors and pretends to offer a new perspective on the strong Goldbach conjecture. The natural numbers are restructured and expanded with the inclusion of the zero element as the source of a strong Goldbach conjecture reformulation. A prime Boolean vector is defined, pinpointing the positions of prime numbers within the odd number sequence. The natural unit primality is discussed in this context and transformed into a source of quantum-like indetermination. This approach allows for rephrasing the strong Goldbach conjecture, framed within a Boolean scalar product between the prime Boolean vector and its reverse. Throughout the discussion, other intriguing topics emerge and are thoroughly analyzed. A final description of two empirical algorithms is provided to prove the strong Goldbach conjecture. 展开更多
关键词 natural Numbers Prime Numbers Vector Description of natural Numbers Prime Boolean Vectors Primality of the natural Unit strong Goldbach’s Conjecture Vector Reversal Pairing Conjecture natural Matrix squeezing
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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead Universe Theory Heat Death of the Universe Big Bang Theory Universe’s Ultimate Fate Universe Expansion Big Freeze Universe Cosmological Models End of Universe Theories natural Galaxy Drift Future of the Universe Universe Cooling Down Cosmology and Entropy
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Pearl S. Buck’s Values of “Cultural Convergence” and Their Application
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作者 WANG Yan ZHU Ze-yuan SHI Hui-ge 《Cultural and Religious Studies》 2023年第1期9-18,共10页
The typical features of internal and external integration of cultures as revealed by the conception of“cultural convergence”provide a new perspective on the study of cultural exchanges and mutual learning.In the con... The typical features of internal and external integration of cultures as revealed by the conception of“cultural convergence”provide a new perspective on the study of cultural exchanges and mutual learning.In the context of“a global community of shared future for humankind”,this paper adopts the novel idea of“cultural convergence”to probe the growth of Pearl S.Buck’s cultural values and the specific contents and representation of Pearl S.Buck’s conception of“cultural convergence”,highlighting the application of Pearl S.Buck’s values to cultural education,growth and success,family education,cultural exchanges,humanistic practices,etc.Feasible suggestions and countermeasures are put forward to better promote the cultural exchanges and mutual learning as well as the convergence of different cultures. 展开更多
关键词 Pearl s.Buck values of“cultural convergence” applied research
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Emotional Value Care to Promote Emotional Communication Between Teachers and Students Under the New Era of Education Mode
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作者 Yongdong Xiao 《Journal of Contemporary Educational Research》 2023年第1期7-12,共6页
With the development of the times and the progress of the society,the ancient education mode can no longer meet the requirements of the times.The concept of educating people must keep pace with the times.The way teach... With the development of the times and the progress of the society,the ancient education mode can no longer meet the requirements of the times.The concept of educating people must keep pace with the times.The way teachers and students get along is no longer like in ancient times,where teachers teach students to listen.In the new era,it is necessary to build a new model of interaction between teachers and students.If educators pay attention and come to understand students’psychology,listen to students’aspirations,tend to students’emotions,grow in love for education,and treat students from their hearts,they would be able to win the favor of students.Paying attention to students’emotional value can promote emotional communication between teachers and students.It is possible to adapt to the requirements of the new era for the construction of morality and ethics among teachers by caring for students’emotional value. 展开更多
关键词 Teacher’s morality Teacher’s style Emotional value Emotional communication
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Natural heritage values and comparative analyses of Kanas,China 被引量:4
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作者 Geoffrey WALL 《Journal of Arid Land》 SCIE 2010年第3期197-206,共10页
Kanas is a National Nature Reserve and National 5A Scenic Area,and it is also high on China’s National Natural Heritage List. In this paper,with an integrated analysis and comparative geo-graphical approach,the genes... Kanas is a National Nature Reserve and National 5A Scenic Area,and it is also high on China’s National Natural Heritage List. In this paper,with an integrated analysis and comparative geo-graphical approach,the genesis and current features of the Kanas landscape are analyzed systematically according to the criteria for outstanding universal values that must be met for designation by the United Nations as World Natural Heritage. It is concluded that Kanas has outstanding universal values in geosciences,biology and aesthetics. Through comparison with other World Natural Heritage sites of the same geological types,in the same biogeographic zone and in the same latitude,it is concluded that Kanas meets criteria vii,viii,ix and x for designation as World Natural Heritage. Thus,this work establishes a scientific foundation for nomination of Kanas for such a status. 展开更多
关键词 natural landscape characteristics heritage value comparative analyses Kanas of Xinjiang
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Natural Heritage Value of Xinjiang Tianshan and Global Comparative Analysis 被引量:5
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作者 XU Xiaoliang YANG Zhaoping +2 位作者 Adayi Saiken Shao Rui LIU Xinyu 《Journal of Mountain Science》 SCIE CSCD 2012年第2期262-273,共12页
Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage status.This paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tiansh... Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage status.This paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tianshan according to the World Heritage criteria.Its biological,ecological and aesthetic values,which are of global importance, are documented.It is concluded that Xinjiang Tianshan meets the world heritage criteria(vii)and (ix).Xinjiang Tianshan is compared with other mountain world heritage sites,mountains in Central Asia,the Tianshan Mountains outside China,and with the protected areas of the Tianshan Mountains on the Tentative List for World Heritage Sites,so as to provide objective data for the world heritage application. 展开更多
关键词 Xinjiang Tianshan natural Heritage Heritage characteristics Heritage values Comparative analysis
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Prognostic Value of Semi-Quantitative 18F-FDG PET/CT Parameters in Hodgkin’s Lymphoma
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作者 Yong Zhou Congyang Hu +7 位作者 Yue Li Xiting Xia Jun Lei Jingyi Chen Hua Xu Mei He Hongyun Jian Shuping You 《Proceedings of Anticancer Research》 2023年第6期108-115,共8页
Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-compu... Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-computed tomography(18F-FDG PET/CT)imaging in Hodgkin’s lymphoma patients.Methods:A total of 148 Hodgkin’s lymphoma patients diagnosed with lymph node biopsy from October 2014 to October 2015 were retrospectively analyzed followed by categorizing into good(125 cases)and poor(23 cases)prognosis groups.The chi-squared test was used to analyze the clinicopathological characteristics of Hodgkin’s lymphoma patients with the semi-quantitative 18F-FDG PET/CT parameters;the Spearman method was used to analyze the correlation between the semi-quantitative parameters and clinicopathological features of Hodgkin’s lymphoma;receiver operating characteristic curve was used to analyze the predictive value of the semi-quantitative parameters for poor prognosis of Hodgkin’s lymphoma patients.Results:Mean SUVmax,MTV,and TLG of the 148 cases of Hodgkin’s lymphoma were 7.26±2.38,12.46±3.14 cm3,and 76.83±18.56 g,respectively.Significant variations in the Ann Arbor stage and clinical classification were observed with different levels of semi-quantitative parameters(P<0.05).The semi-quantitative parameters were not correlated with age and gender(P>0.05)but positively correlated with Ann Arbor stage and clinical classification(P<0.05).These parameters in the poor prognosis group were higher than those in the good prognosis group(P<0.05).The area under the curve(AUC)of SUVmax,MTV,and TLG in predicting the poor prognosis group was 0.881,0.875,and 0.838,with cut-off values of 7.264,12.898 cm3,and 74.580g,as well as specificity of 88.8%,84.0%,and 78.4%,and sensitivity of 87.0%,87.0%,and 78.3%,respectively;the AUC of the combined prediction was 0.986,with a specificity of 97.6%and sensitivity of 86.3%.Conclusion:The semi-quantitative 18F-FDG PET/CT parameters provide valuable insights for Hodgkin’s lymphoma prognosis assessment. 展开更多
关键词 Hodgkin’s lymphoma 18F-fluorodeoxyglucose positron emission tomography-computed tomography Maximum standardized uptake value Metabolic tumor volume Total lesion glycolysis PROGNOsIs
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Simulation Study on Heat Value Control System of Natural Gas Used for Color TV Tubes Production 被引量:1
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作者 郑斌 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期283-287,共5页
In order to know the character of the heat value control system, determine the influence of natural gas quality and flow on the heat value, and learn how to adjust the parameters of control system, the model of the wh... In order to know the character of the heat value control system, determine the influence of natural gas quality and flow on the heat value, and learn how to adjust the parameters of control system, the model of the whole system is established, and simulation of the system is adopted in Matlab/Simulink. The simulation result shows that the feedback system with feed-forward block controls the heat value very well, and the simulation result can effectively guide the engineering design of the heat value control system, and the efficiency of engineering is improved. 展开更多
关键词 natural gas heat value control system simulation
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Values of the Times of Marx's Theory of Science and Technology Progress and Utilization of Natural Resources 被引量:1
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作者 Jiefang ZHU 《Meteorological and Environmental Research》 CAS 2020年第4期78-82,共5页
Marx's theory of scientific and technological progress and utilization of natural resources is an indispensable and important part of Marx's economic theory.To realize the harmonious unification of man and nat... Marx's theory of scientific and technological progress and utilization of natural resources is an indispensable and important part of Marx's economic theory.To realize the harmonious unification of man and nature,man must correctly understand the effect of scientific and technological progress on the use of natural resources,fundamentally solve the problem that scientific and technological progress cannot replace the position of natural resources in economic development,and objectively evaluate the relationship between human power and the power of nature.Grasping and comprehending the scientific connotation of Marx's theory of scientific and technological progress and utilization of natural resources has a very important theoretical value and practical significance for saving and effectively using natural resources and building an environment-friendly society. 展开更多
关键词 scientific and technological progress Utilization of natural resources values of the times
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Evaluating Value of Natural Landscapes in China 被引量:1
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作者 XIAO Yi CHENG Cheng +2 位作者 YANG Wu OUYANG Zhiyun RAO Enming 《Chinese Geographical Science》 SCIE CSCD 2016年第2期244-255,共12页
Natural landscapes consist of the natural substances, environment, and phenomena, all of which provide many benefits to people, including a sense of place, sightseeing, relaxing, and recuperating. However, the economi... Natural landscapes consist of the natural substances, environment, and phenomena, all of which provide many benefits to people, including a sense of place, sightseeing, relaxing, and recuperating. However, the economic value of natural landscapes has only been recognized in recent decades, and the resulting large-scale decline and degradation of ecosystems now severely threatens the sustainable provision of their services to society. There is an emerging consensus that natural capital should be incorporated into the current socioeconomic accounting system. Many studies valuated natural resources at local and regional scales, but there are very few empirical studies at a national level. To provide a benchmark for natural landscape management on a national scale, we use the travel cost method(TCM) and the contingent valuation method(CVM) to determine the economic value and the spatial distribution of natural landscapes across China. Our results show that the total economic value of China′s natural landscape was 9.75 × 10^(11) U.S. dollars(USD) in 2012. Of this value, the highest proportion was in the eastern and southwestern regions of China, which accounts for 23.7% and 18.3%, respectively. The provinces of Guangdong, Sichuan, Yunnan, Inner Mongolia, and Heilongjiang were the top five in terms of the largest number of natural landscapes and largest economic values. Together, these five provinces accounted for 32.9% of the total number of natural landscapes and 29.4% of the total economic value in 2012. We believe this study will increase awareness of the value of natural landscapes, and more importantly provide a scientific basis for resolving conflicts between development and resource conservation. 展开更多
关键词 travel cost method(TCM) contingent valuation method(CVM) natural landscape value China
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