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敬老情怀——记福州个体司机林新
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作者 毅杰 《安全与健康》 2004年第22期25-25,共1页
帮助老人,甚至还把老人接到家里,很多人都感到实在不可思义……可他只是笑呵呵地对人们说:“谁又不会老呢?”他就是鼓楼区个体司机林新,而他所开的车.乃是一部货运龙马车。但他就是用这辆车.为老人服务了十几载。他说,只要有心... 帮助老人,甚至还把老人接到家里,很多人都感到实在不可思义……可他只是笑呵呵地对人们说:“谁又不会老呢?”他就是鼓楼区个体司机林新,而他所开的车.乃是一部货运龙马车。但他就是用这辆车.为老人服务了十几载。他说,只要有心,开什么车都一样,都能实现他为老人服务的情怀。他之所以有着这样的敬老情怀, 展开更多
关键词 福州市 驾驶员 林新 人生态度
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新课标下的教材革新:译林版七年级英语新教材系统性分析
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作者 祝心恬 《教育进展》 2024年第8期920-924,共5页
教育是国家发展的基石,而教材则是教育过程中传递知识与价值观的重要媒介,其质量直接关系到教育的效果,而新课标的颁布则更为明确地对教材编写提出了新的时代性要求。本研究聚焦于译林出版社2024年版义务教育阶段新教材的系统性分析,以7... 教育是国家发展的基石,而教材则是教育过程中传递知识与价值观的重要媒介,其质量直接关系到教育的效果,而新课标的颁布则更为明确地对教材编写提出了新的时代性要求。本研究聚焦于译林出版社2024年版义务教育阶段新教材的系统性分析,以7A教科书为例,探讨其适应现代教育理念的变革与特点。在全球教育趋势和新课标要求的背景下,本文旨在评估新教材的主要变化及突出特点,并提出使用建议,以提升教学效果和学生学习体验的影响,促进教育质量的提升。Education is the cornerstone of national development, and textbooks are an important medium for conveying knowledge and values in the educational process. The quality of textbooks is directly related to the effectiveness of education, and the issuance of new curriculum standards has put forward new era requirements for textbook compilation more explicitly. This study focuses on the systematic analysis of the new textbooks for the compulsory education stage published by Yilin Press in 2024, taking the 7A textbook as an example, to explore its changes and characteristics in adapting to modern educational concepts. Against the backdrop of global educational trends and the requirements of the new curriculum standards, this paper aims to evaluate the main changes and prominent features of the new textbooks, and to put forward suggestions for use, in order to enhance the impact of teaching effectiveness and student learning experience, and to promote the improvement of educational quality. 展开更多
关键词 义务教育新课标 林新教材 教材分析
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基于改进IDI指标体系的G20成员国信息通信技术发展水平研究
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作者 刘亚丽 唐宏博 +2 位作者 林茜妍 梁正 赵新力 《全球科技经济瞭望》 2023年第4期34-40,共7页
在国际电信联盟曾使用的信息通信技术(ICT)发展指数(IDI)基础上,提出改进的信息通信技术发展指数。通过分析2007—2020年二十国集团(G20)的19个成员国的IDI指数和ICT相关指标揭示了G20成员国在信息通信技术发展方面的特点和差异性。分... 在国际电信联盟曾使用的信息通信技术(ICT)发展指数(IDI)基础上,提出改进的信息通信技术发展指数。通过分析2007—2020年二十国集团(G20)的19个成员国的IDI指数和ICT相关指标揭示了G20成员国在信息通信技术发展方面的特点和差异性。分析发现G20成员国信息通信技术发展水平均有较大幅度的提升,国家之间的信息通信技术发展差距逐渐缩小,但增长速度和发展水平仍存在较大差异;G20成员国中韩国、日本、法国、德国和英国的信息通信技术发展水平最高,美国、加拿大、澳大利亚、沙特阿拉伯和俄罗斯的信息通信技术发展居于G20成员国的中上水平,意大利、阿根廷、中国、巴西、土耳其的发展居于中下水平,墨西哥、南非、印度尼西亚和印度的信息通信技术发展水平较低。 展开更多
关键词 G20 信息化 数字化 信息通信技术发展指数 ICT IDI
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Greening Strategies for the Construction of Eco-garden City in Xinjiang
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作者 杨帆 杨逢玉 郭润华 《Journal of Landscape Research》 2010年第2期36-38,共3页
There are a lot of problems in urban greening strategies for Xinjiang due to geographical conditions, climate and humanity. Based on the construction of eco-garden city in Xinjiang, this paper analyzed the greening pr... There are a lot of problems in urban greening strategies for Xinjiang due to geographical conditions, climate and humanity. Based on the construction of eco-garden city in Xinjiang, this paper analyzed the greening problems during the construction of eco-garden city, so as to provide a reference for the greening construction of eco-garden city in Xinjiang. 展开更多
关键词 Eco-garden city Garden greening XINJIANG
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Two New Species of the Genus Rondaniella Johannsen (Diptera:Mycetophilidae) from China 被引量:2
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作者 余晓霞 吴鸿 +2 位作者 陈学新 时敏 吴琼 《Entomotaxonomia》 CSCD 北大核心 2004年第4期288-292,共5页
In this paper two new species of Rondaniella Johannsen, 1909 from China are described. The type specimens are deposited in Zhejiang Forestry College, China.
关键词 DIPTERA MYCETOPHILIDAE Rondaniella new species China
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Natural regeneration characteristics of Pinus sylvestris var. mongolica forests on sandy land in Honghuaerji, China 被引量:20
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作者 ZHU Jiao-jun KANG Hong-zhang +2 位作者 TAN Hui XU Mei-ling WANG Jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期253-259,共7页
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values o... Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values of regeneration indexes were higher in mature stands (more than 80% individual stems were older than 50 years), the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation (e.g. about 80-year old). The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future. 展开更多
关键词 Pinus sylvestris var. mongolica Mongolian pine Sandy land Natural regeneration Canopy openness Forest gap Regeneration index
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Effects of thinning on microsites and natural regeneration in a Larix olgensis plantation in mountainous regions of eastern Liaoning Province, China 被引量:6
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作者 LIU Zu-gen ZHU Jiao-jun +4 位作者 HU Li-le WANG He-xin MAO Zhi-hong LI Xiu-fen ZHANG Li-jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期193-199,共7页
In order to understand the effects of thinning on microsite conditions and natural regeneration in the larch plantation, thinning experiment was conducted in a 40-year-old Larix olgensis plantation in Qingyuan County ... In order to understand the effects of thinning on microsite conditions and natural regeneration in the larch plantation, thinning experiment was conducted in a 40-year-old Larix olgensis plantation in Qingyuan County in eastern Liaoning Province, China in 2003-2004 Five thinning treatments (0%, 10.2%, 19.8%, 29.7% and 40.3% thinned) were designed on the same site. After thinning, canopy openness and the microsite conditions such as photosynthetic photon flux density (PPFD), soil moisture content, and soil temperature were measured in one growing season. Meanwhile, the investigation of natural regeneration was conducted at the end of the growing season. The results showed that the canopy openness increased with the increase of thinning intensities. PPFD and soil temperature and soil moisture content in different soil layers were positively relative with canopy openness after thinning. The richness of regenerating tree species did not significantly increase (p=0.30) after one growing season since thinning, but the regeneration density and frequency of tree species increased significantly (p〈0.05). In addition, the number of regenerating tree species increased, and the increment was correlated with the characteristics of iudividual tree species. The increasing percentage of regenerating seedlings of the shade-intolerant tree species was more than that of shade-tolerant tree species. Among the investigated regeneration species, the biggest response of seedling emergency to the canopy openness was Phellodendron amurense. This paper confirmed the following conclusions: after thinning, the variety of regenerating tree species was correlative with the characteristics of regenerating tree species, and the distribution of unthinned trees and the site conditions in the investigated larch plantation were the additional factors influencing, the regeneration. 展开更多
关键词 Larix olgensis plantation THINNING MICROSITE Natural regeneration
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Effect of shelterwood cutting method on forest regeneration and stand structure in a Hyrcanian forest ecosystem 被引量:2
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作者 Mohammad Reza Pourmajidian Hamid Jalilvand +4 位作者 Asghar Fallah Seyed Ataollah Hosseini Aidin Parsakhoo Amin Vosoughian Ali Rahmani 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期265-272,395,共9页
A study was carried out to evaluate the effect of shelterwood cutting methods on stand structure and regeneration density. Data were collected from a northern hardwood forest stands in Iran with Fagus orientalis Lipsk... A study was carried out to evaluate the effect of shelterwood cutting methods on stand structure and regeneration density. Data were collected from a northern hardwood forest stands in Iran with Fagus orientalis Lipsky as dominant species, with/without shelterwood cutting operation. Results clearly demonstrate that the management of Fagus orientalis Lipsky with shelterwood cutting system affected the frequency and diversity of the understory herbaceous species. The frequency of Viola silvestris Lam., Asperula odorata L., Carex spp. and Rubus hyr-canus Juz increased significantly after shelterwood cutting. The DBH (diameter at breast height) of commercial species in control stands (57.50±2.15 cm) was greater than that in treated stands (50.67±1.88 cm), whereas the total height of trees was similar between treated and control plots (21±0.5 m). The number of Parrotia persica seedlings increased by 13.2% from 1995 to 2005 whereas the number of Fagus orientalis and Carpinus betulus seedlings significantly decreased from 1995 to 2005. In conclusion, it confirms that instead of shelterwood cutting method other silvicultural practices such as selection cutting method should be applied for the mountainous beech stands of Hyrcanian forests. 展开更多
关键词 Shelterwood cutting stand structure REGENERATION Fagus orientalis Lipsky
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Ecological Responses to Holocene Millennial-Scale Climate Change at High Altitudes of East and Central Asia: A Case Study of Picea/Abies Pollen Changes in Lacustrine Sediments 被引量:2
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作者 LI Yu ZHANG Cheng-qi ZHOU Xue-hua 《Journal of Mountain Science》 SCIE CSCD 2014年第3期674-687,共14页
Ecosystem response to climate change in high-altitude regions is a focus on global change research. Picea/Abies forests are widely distributed at high altitudes of East and Central Asia, and their distribution changes... Ecosystem response to climate change in high-altitude regions is a focus on global change research. Picea/Abies forests are widely distributed at high altitudes of East and Central Asia, and their distribution changes are sensitive to climate change. Humidity is an important climatic factor that affects high-altitude ecosystems; however, the relationship between distribution changes of Picea/Abies forests and millennial-scale variability of humidity is still not dear. Palynological records can provide insights into millennial-scale paleovegetation changes, which have been successfully used to reconstruct past climate change in East and Central Asia. In this study, we synthesized 24 Picea/Abies pollen and humidity/moisture changes based upon Holocene lake records in East and Central Asia in order to explore the response of high-latitude ecosystem to millennial-scale climate change. The changing pattern of Holocene lacustrine Picea/Abies pollen in arid Central Asia differs from that of monsoonal East Asia, which can be due to different millennial-scale climate change patterns between monsoonal and arid Central Asia. Then, the relationship between changes in Picea/Abies pollen and humidity/moisture conditions was examined based on a comparison of pollen and humidity/moisture records. The results indicate that millennial-scale Picea/Abies distribution changes aremainly controlled by moisture variability at high altitudes, while the temperature effect plays a minor role in Picea/Abies distribution changes. Moreover, this research proves that lacustrine Picea/Abies pollen can be used as an indicator of millennial-scale humidity/moisture evolution at high altitudes in East and Central Asia. 展开更多
关键词 Lake sediments Palynological records High-altitude regions Picea/Abies Asian summermonsoon MILLENNIAL-SCALE Climate change
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Research on Institutional Innovation of Non-public Forestry 被引量:3
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作者 Yao Shunbo Wang Bowen Liu Cang 《Ecological Economy》 2005年第4期87-91,共5页
This article analyzes the form and the mechanism of non-public forestry's institution obstacles by classical economies, institution economics', legal economics and economic theories of modern forestry. Regarding the... This article analyzes the form and the mechanism of non-public forestry's institution obstacles by classical economies, institution economics', legal economics and economic theories of modern forestry. Regarding the proprietary institution as the core, and cost-income as the main clewf-it defines the concept and eategory, of non-public forestry subsidy and compensation. And oecorrling to the relased control and efficiency principle of market econonf-this paper establishes a set of institution that accords with the development of non-public forestry, offers both theoretical supports and decision- making references to remove institution obstacles of nan-public forestry, and coordinates the policies of non-public forestry with those of the public-owned forestry. 展开更多
关键词 non-publie forestry institutional innovation
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Remote sensing analysis of mangrove distribution and dynamics in Zhanjiang from 1991 to 2011 被引量:3
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作者 LIU Dazhao LI Shanshan +1 位作者 FU Dongyang SHEN Chunyan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第5期1597-1603,共7页
Mangrove forests provide valuable societal and ecological services and goods. However, they have been experiencing high annual rates of loss in many parts of the world. In order to evaluate a long-term wetland conserv... Mangrove forests provide valuable societal and ecological services and goods. However, they have been experiencing high annual rates of loss in many parts of the world. In order to evaluate a long-term wetland conservation strategy that compromises urban development with comprehensive wetland ecosystem management, remote sensing techniques were used to analyze the changing mangrove distribution in the Zhanjiang Mangrove Forest National Nature Reserve. Between 1991 and 2000, the mangrove area within the study region declined from 2 264.9 to 2 085.9 ha consistent with an annual decrease of 0.79%. However, there was an overall 34.3% increase in mangrove coverage from 2 085.9 to 2 801.8 ha between 2000 and 2011. Major causes of forest loss include local human pressures in the form of deforestation, conversion to agriculture, and natural forces such as erosion. The recent gain in mangrove forest cover is attributed to eff ective conservation management in the nature reserve area, including intensive mangrove plantation eff orts and increased local awareness of wetland conservation. 展开更多
关键词 MANGROVE landsat TM/ETM+ HJ-1A CONSERVATION remote sensing
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Comparative regeneration status in a natural forest and enrichment plantations of Chittagong (south) forest division, Bangladesh
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作者 M. Kamal Hossain M. Lutfor Rahman +1 位作者 A. T. M. Rafiqul Hoque M. Khairul Alam 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期255-260,共6页
The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat metho... The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat method during April 2002 to November 2002. Totally 100 plots of 3 m X 3 m in size represents a total of 64 regenerating tree species from natural forest with an average seedlings of 24767/hm2, while only 40 regenerating tree species were recorded from enrichment plan-tations with an average seedlings of 18633/hm2. Maximum regeneration in natural forest was found with Castanopsis spp. (2200 seedlings/hm2) followed by Glochidion lanceolarium (2183 /hm2) whereas, in enrichment plantations maximum regen-eration was found with Dipterocarpus gracilis (2117/hm2) followed by Anogeissus acuminata (2000/hm2). For natural forest, highest relative density was found for Castanopsis spp (8.88%), relative frequency for Glochidion lanceolarium (7.36%), rela-tive abundance for Syzygium spp. (3.79%) and Importance Value Index were recorded with Glochidion lanceolarium (18.24%). The corresponding values for enrichment plantations were highest with Dipterocarpus gracilis (11.36%), Glochidion lanceo-larium (9.71%), Dipterocarpus gracilis (5.92%), Glochidion lanceolarium (23.32%) respectively. Stem per hectare of some common trees with their seedlings and saplings in both the natural stands and enrichment plantations showed that only Dip-terocarpus gracilis successfully recruited in both sites but recruitment was higher in natural forest. Like many other primary rain forests, the Baraitoli forest typically has both substantial seedlings and soil seed bank from which regeneration may occur. The naturally regenerated seedlings are quite dense but it could not reach the pole stage due to human interference. 展开更多
关键词 REGENERATION Natural forest Enrichment plantations Relative density Frequency ABUNDANCE Importance Value Index
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The prescription rule analysis of the New Theory on Spleen Dampness Syndrome by Academician TONG Xiaolin 被引量:2
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作者 ZHENG Jinghui LI Lijuan +4 位作者 HUANG Feijian CHEN Xuan LEI Ye ZHU Xiangdong LIU Wenke 《Digital Chinese Medicine》 2022年第1期33-48,共16页
Objective To analyze the basic characteristics,drug features,prescription rules,and drug-symptom relationships of patients in the splenic deficiency and impairment stage,by data mining of medical records under the New... Objective To analyze the basic characteristics,drug features,prescription rules,and drug-symptom relationships of patients in the splenic deficiency and impairment stage,by data mining of medical records under the New Theory on Spleen Dampness Syndrome(Pi Dan Xin Lun,《脾瘅新论》).Methods Medical records listed in the“New Theory on Spleen Dampness Syndrome-Under-standing and Treatment of Metabolic Syndrome from the Perspective of Traditional Chinese Medicine”,and which were diagnosed with the spleen dampness syndrome at the splenic de-ficiency and impairment stage,during January 2004 and December 2016 were selected.These patients’data,including basic information,clinical symptoms,laboratory examination res-ults,traditional Chinese medicine(TCM)and western medicine diagnoses,treatment meth-ods,prescriptions,etc.,were collected.The collected data were subsequently compiled into a medical record database using the Epidata 3.1 data management software,followed by the use of Apriori algorithm provided in the SPSS Modeler 14.2 statistical software to investigate the association rules between drug-drug,drug-symptom,and drug-western medicine indices.Results(i)A total of 51 medical records were included,involving 17 types of syndromes.Among them,the top three with frequency≥3 included“Phlegm and blood stasis,and thoracic obstruction”“Deficiency-weakness of the spleen Qi,and static blood blocking collat-erals”,and“Deficiency-weakness of the spleen Qi,and static blood blocking collaterals”.Al-ternatively,of the 14 treatment methods,the top three treatments with frequency of≥3 in-cluded“Activating Yang and eliminating turbidity,and removing phlegm and dredging chan-nel blockage”“Strengthening the spleen and benefiting Qi,and eliminating phlegm to activ-ate the channels”,and“Warming Yang and benefiting Qi,and expelling cold to remove ob-structions”.Among the 15 prescriptions,the top three used with frequency≥3 included Huangqi Guizhi Wuwu Tang(黄芪桂枝五物汤),Gualou Xiebai Banxia Tang(瓜蒌薤白半夏汤),and Ganjiang Huangqin Huanglian Renshen Tang(干姜黄芩黄连人参汤).Lastly,of the 83 drugs used for a total of 476 times,those with frequency≥15 included Huanglian(Coptid-is Rhizoma),Huangqi(Astragali Radix),Jiudahuang(Wine-processed Rhei Radix et Rhizoma),Jixueteng(Spatholobi Caulis),Shengjiang(Zingiberis Rhizoma Recens),Huangqin(Scutellariae Radix),and Guizhi(Cinnamomi Ramulus).(ii)For the drug-drug associations,under the criteria of support≥15%and confidence=100%,seven second-order association rules,seven third-order rules,and six fourth-order roles were identified.The top-ranking rule of each was“Huangqin(Scutellariae Radix)→Huanglian(Coptidis Rhizoma)”“Ganjiang(Zingiberis Rhizoma)+Huangqin(Scutellariae Radix)→Huanglian(Coptidis Rhizoma)”,and“Baishao(Paeoniae Radix Alba)+Guizhi(Cinnamomi Ramulus)+Jixueteng(Spatho-lobi Caulis)→Huangqin(Scutellariae Radix)”,respectively.Alternatively,the drug-symptom associations were analyzed under the criteria of support≥5%and confidence=100%,which derived eight second-order association rules,31 third-order rules,and 30 fourth-order rules.The top-ranking association rule of each order was“Huangqi(Astragali Radix)→Limb ed-ema”“Guizhi(Cinnamomi Ramulus)+Jixueteng(Spatholobi Caulis)→Limb numbness and pain”,and“Guizhi(Cinnamomi Ramulus)+Jixueteng(Spatholobi Caulis)+Huangqi(As-tragali Radix)→Limb numbness and pain”,respectively.Similarly,the drug-western medi-cine index associations were investigated under the criteria of support≥5%and confidence=100%,and five second-order association rules,16 third-order rules,and 16 fourth-order rules were identified.In this category,the top-ranking association rule of each order was“Qinpi(Fraxini Cortex)→Uric acid”“Huanglian(Coptidis Rhizoma)+Ganjiang(Zingiberis Rhizoma)→Glycated hemoglobin”,and“Huanglian(Coptidis Rhizoma)+Ganjiang(Zing-iberis Rhizoma)+Huangqin(Scutellariae Radix)→Glycated hemoglobin”,respectively.Conclusion Through association rule mining,this study objectively and quantitatively demonstrated the drug-drug,drug-symptom,and drug-physicochemical index associations of patients with the spleen dampness syndrome at the splenic deficiency and impairment stage treated by Academician TONG Xiaolin.The results indicated that treatment for these patients adopted the“state-target”syndrome differentiation method.The drug combination was characterized by“small prescriptions”,targeting both the patient’s symptoms and signs(syndrome target)and western medicine indices(treatment target).This study could provide references for future research on the academic thoughts and medical experience of Academi-cian TONG Xiaolin. 展开更多
关键词 TONG Xiaolin Spleen dampness syndrome New Theory on Spleen Dampness Syn-drome(Pi Dan Xin Lun 《脾瘅新论》) Deficiency and impairment stage Data mining Association rules
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Presence of Black Carbon in Soil due to Forest Fire in the New Jersey Pine Barrens
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作者 Bente Foereid Johannes Lehmann +1 位作者 Christopher Wurster Michael Bird 《Journal of Earth Science and Engineering》 2015年第2期91-97,共7页
Fire is an important ecological factor and what constitutes appropriate fire management is much debated in the US and elsewhere. The role of fire as a source of greenhouse gases has been intensively investigated, but ... Fire is an important ecological factor and what constitutes appropriate fire management is much debated in the US and elsewhere. The role of fire as a source of greenhouse gases has been intensively investigated, but less is known about the production rate of the solid black carbon residue from fires. Black carbon accumulates in soil as it has longer turnover times than plant residues. To understand the significance of black carbon production during wildfire, we quantified black carbon using hydropyrolysis in O and A horizons before and after a prescribed bum at four sites in the New Jersey Pine Barrens forest in the North-Eastern US. Black carbon was found in both O- and A-horizons at all investigated sites, stocks in the range of 61.31-168.15 g m^-2 in the O-horizon and 169.59-425.25 g m^-2 in the A-horizon. Total black carbon stocks did not increase following the fire suggesting that either black carbon production in fires may be small compared to the variability, or that equivalent amounts of black carbon formed in previous fires may have been consumed in the fire. The study raises questions about how black carbon production and consumption in ftres can be quantified separately. 展开更多
关键词 Black carbon soil properties prescribed fire New Jersey Pine Barrens.
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Structure and regeneration dynamics of three forest types at different succession stages of spruce – fir mixed forest in Changbai Mountain, northeastern China 被引量:6
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作者 GUO Wei-wei WANG Xin-jie +4 位作者 KANG Xin-gang ZHANG Qing MENG Jing-hui ZHANG Meng-tao JI Lei 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1814-1826,共13页
Analyzing and understanding the structure and growth dynamics of forests at different stages is helpful to promote forest succession, restoration and management. Three spots representing three succession stages of spr... Analyzing and understanding the structure and growth dynamics of forests at different stages is helpful to promote forest succession, restoration and management. Three spots representing three succession stages of spruce-fir mixed forest(SF: polar-birch secondary forest, MF: spruce-fir mixed forest and PF: spruce-fir near primary forest) were established. Structure, growth dynamics during two growth seasons for dominant tree species, regeneration were examined, and a univariate O-ring function statistic was used to analyze the spatial patterns of main regeneration tree species. Results showed that,(1) composition of tree species, periodic annual increment(PAI) of the diameter at breast height(DBH), basal area for overstory trees and of ground diameter(DGH) for saplings, were significantly different with the succession;(2) the current species composition and regeneration dynamics of SF suggested a development towards spruce-fir mixed forests. Pioneer species like Betula platyphyllaa will gradually disappear while climax species, such as Abies nephrolepis, Pinus koraiensis, Picea koraiensis and Tilia amurensis will dominate forest stands;(3) Despite the highest volume occurring in PF, and saplings in it grew better than in the others, this forest type is unstable because of its unsustainable structure of DBH class and insufficient regeneration; and(4) MF had the most reasonable distribution of DBH class for adult trees(DBH > 5.0 cm) and DGH class for saplings(H ≥30 cm and DBH ≤5 cm), as well as an optimal volume increment. Limiting canopy opening size can lessen the physiological stress and promote the growth and competitive status of regeneration. Management implications for increasing the gaps and thus creating better growth conditions for understory saplings and facilitating forest succession were discussed. 展开更多
关键词 Forest succession Saplings Structure and growth Spatial pattern Changbai Mountain
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The Spirit of Zhuangzi and Chinese Utopian Imagination
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作者 LIU Jianmei 《Journal of Literature and Art Studies》 2015年第11期970-984,共15页
Through examining Zhou Zuoren's ideal of new village and Lin Yutang's novel Unexpected lsland, this article analyzes modem Chinese utopian imaginations inspired by Zhuangzi's spirit, which complements what has been... Through examining Zhou Zuoren's ideal of new village and Lin Yutang's novel Unexpected lsland, this article analyzes modem Chinese utopian imaginations inspired by Zhuangzi's spirit, which complements what has been lacking in the modem utopian dream--individual spiritual liberation that resists any despotism of humanity and a more tolerant and multifaceted cultural mentality that fights against the unification of thought. 展开更多
关键词 Utopian ZHUANGZI Lin Yutang Zhou Zuoren Yan Lianke Ge Fei
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Seasonal changes of bioelements in litter and their potential return to green leaves in five species of tropical dry deciduous forest, western India
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作者 J. I. Nirmal Kumar Rita N Kumar +1 位作者 Rohit Kumar Bhoi Kanti Patel 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期33-38,I0002,共7页
The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia n... The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia nilotica, Acacia leucophloea. Tectona grandis, Miliusa tomentosa and Butea monosperma in Indian tropical dry deciduous forest in Western India.. Total dry matter of plant species was recorded and analyzed for N, P, Ca, Mg, K and Na. A. nilotica had the highest concentrations of N in leaf, while ,4. leucophloea had the highest concentrations of Ca and Mg in leaf. The highest concentrations of P in leaf were found in A. nilotica, A. leucophloea and B. monosperma where as lowest in T. grandis and M. tomentosa. No significant differences in K and Na were registered among the species. A marked seasonal variability was ob- served in the concentrations of N, P and K, except for Ca and Mg. Potas- sium is the single element that undergoes leaching and mobilization in all species. Resorped N and P can be used for the production of fresh leaf in the following annual cycle. Nutrient resorption and retranslocation from senescent leaves and litter supports the production of new foliage and increase the fertility of soil. 展开更多
关键词 Tropical dry deciduous forest nutrient concentration senescent and fresh leaves nutrient return nutrient resorption efficiency
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Effects of Disturbance Intensities on Vegetation Patterns in Oak Forests of Kumaun,West Himalaya 被引量:2
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作者 Ranbeer S.RAWAL Sanjay GAIROLA Uppeandra DHAR 《Journal of Mountain Science》 SCIE CSCD 2012年第2期157-165,共9页
In order to realize the significance of oak forests for ecology and economy of the Himalayan region,the present study attempts to objectively characterize disturbance intensities and their impacts on compositional fea... In order to realize the significance of oak forests for ecology and economy of the Himalayan region,the present study attempts to objectively characterize disturbance intensities and their impacts on compositional features of identified Oak forests, i.e.Banj-oak(Quercus leucotrichophora A.Camus), Tilonj-oak(Q.floribunda Lindley)and Kharsu-oak(Q. semecarpifolia J.E.Smith)in west Himalaya. Amongst studied forests,Q.leucotrichophora and Q. semecarpifolia forests exhibited high sensitivity towards disturbance intensities.In both forests, increasing level of disturbance significantly lowered tree density,dominance and natural recruitment (seedling and sapling density).Q.floribunda forests, however,appeared relatively more resilient to anthropogenic disturbances.Amongst studied oak forests,Q.semecarpifolia forests with overall poor natural regeneration are in a most critically endangered demographic state.However,a slightly improved regeneration(i.e.,seedling density)in moderately disturbed plots is indicative that such plots may be utilized most suitably for in situ revival of these forests.Effect of disturbance intensities on tree population is an important subject for forest ecology and management and the present study highlights a need for adopting different management strategies across disturbance intensities in diverse oak forests of west Himalaya. 展开更多
关键词 Forest vegetation Anthropogenic disturbance Oak forests west Himalaya
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Composition,Structure and Regeneration Dynamics of Olea ferruginea Royle Forests from Hindukush Range of Pakistan
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作者 NASRULLAH Khan FAYAZ Ali +1 位作者 KISHWAR Ali SHAHID Shaukat 《Journal of Mountain Science》 SCIE CSCD 2015年第3期647-658,共12页
Abstract" The abundance of Olea ferruginea in Malakand Division has been significantly reduced across its distribution range due to anthropogenic pressure in the recent past. A number of initiatives were taken for gr... Abstract" The abundance of Olea ferruginea in Malakand Division has been significantly reduced across its distribution range due to anthropogenic pressure in the recent past. A number of initiatives were taken for grafting this species to obtain better seeds for oil production, without the basic information on their ecology and management. To address this knowledge gap, we quantified the composition, structure and regeneration dynamics of Olea ferruginea forests in Malakand Division, Hindukush range of Pakistan. In the present study, five communities dominated by Oleaferruginea were identified using Ward's agglomerative cluster analysis. Total tree density ranged from 153-26o2 plants/ha, and basal area from 19.55 to 2353 m~ ha-1 with Olea having a relative density of 51% to 87% and basal area of 48% to 93%, respectively. The density of juveniles of the dominant and subordinate tree species were generally low which reflect their narrow distribution in the study area. Size-class distributions of O. ferruginea disclosed a bell-shaped pattern, indicating that forests were heavily exploited by local inhabitants in previous periods and recently by armed forces owing to security risks in the study area. The age (mean max. 300±34 years) and annual increment (3.2±1.2 years/cm) indicates that the species is long lived and generally slow growing among the different broad leaved species studied so far. However, the oldest trees can be found by the exploration of large diameter trees in the area. In addition, we found a stable linear relationship between the age and diameter (r2 = o.779), indicating that diameter is a good predictor of age for this broad leaved species. In view of its relatively slow growth, longevity and positive ring-width characteristics O. ferruginea seems to be a suitable choice for dendroecological and dendrochronological studies in lesser Himalayan and Hindukush ranges of Pakistan. The results obtained from this study may help in understanding the composition, structure and regeneration dynamics of other subtropical broad leaved species. 展开更多
关键词 Oleaferruginea Species composition Ward's agglomerative cluster analysis SEEDLING DENDROECOLOGY
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Roosting Territory of White Ear-Lobed Red Jungle Fowl (Gallus gallus gallus)
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作者 Sawal Wanghongsa Hideki Endo Yoshihiro Hayashi 《Journal of Life Sciences》 2018年第2期75-82,共8页
RJF (red jungle fowl) (Gallus gallus gallus) is territorial birds. Only males advertise and defend territory by metals of crows and combat fighting in severe cases. Crows are testosterone dependent and use up to 4... RJF (red jungle fowl) (Gallus gallus gallus) is territorial birds. Only males advertise and defend territory by metals of crows and combat fighting in severe cases. Crows are testosterone dependent and use up to 4-5% of their basal metabolic rate. Crows race individual voice signatures which differ in tone, duration and vibration. Crows together with radio-telemetry were used here to locate night roosts of dominant males. Between 2005 and 2009, 10 despots were intensively monitored. Outermost locations of individual's roosts were connected to form territory and a distance of 50 m was buffered to individual's territory to yield home range. Data indicated strong site fidelity of dominant males. The longest territory tenure was 31 months. The life time territory of males was on average 10.24 ha (±1.73 SE) and a home range was 17.59 ha (±2.15 SE). Average yearly territory vmcied between 5.48 and 10.88 ha per individual and rarely overlapped. Some roosts were used repeatedly at the same point. In the night, RJF was relatively safe and difficult to approach both vertically and horizontally. Roost site selections were thus a trade-off between security and territory proclamation. 展开更多
关键词 RJF Gallus gallus gallus TERRITORY home range CROW Khao Ang Rue Nai.
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