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我国旅行社集团化发展中的问题与对策 被引量:5
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作者 付美蓉 丁武军 《企业经济》 北大核心 2003年第11期121-123,共3页
随着改革进程的加快和入世,我国旅行社行业,如今已经走到了历史的十字路口,正处在重新洗牌的紧要关头,旅行社集团化是必然选择,它需要远见卓识,战略合作,需要社会的资源整合,需要有利于其发展的政策环境。我国旅游业的发展有其特殊的环... 随着改革进程的加快和入世,我国旅行社行业,如今已经走到了历史的十字路口,正处在重新洗牌的紧要关头,旅行社集团化是必然选择,它需要远见卓识,战略合作,需要社会的资源整合,需要有利于其发展的政策环境。我国旅游业的发展有其特殊的环境,因此,旅行社集团化发展过程还需“市场主导,政府引导”。 展开更多
关键词 旅行社 集团化 上海春秋 广之旅 国中青 旅游联合体 战略合作
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Changing patterns of colorectal cancer in China over a period of 20 years 被引量:93
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作者 Ming Li Jin Gu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第30期4685-4688,共4页
AIM: To determine whether any changes have occurred on the patterns of colorectal cancer in China. METHODS: Data from 21 Chinese articles published from 1980 to 1999, were used to analyze the time trend of colorecta... AIM: To determine whether any changes have occurred on the patterns of colorectal cancer in China. METHODS: Data from 21 Chinese articles published from 1980 to 1999, were used to analyze the time trend of colorectal cancer according to the patients'age at diagnosis, sex, the site of the tumor, stage, and the pathology. RESULTS: From 1980s to 1990s, the mean age of the colorectal cancer patients has increased. The percentage of the female patients rose. The distribution of colorectal carcinoma shows a predominance of rectal cancer. However, the proportion of proximal colon cancer (induding transverse and ascending colon) increased significantly accompanied by a decline in the percentage of rectal cancer. Similarity in the percentage of distal colon cancer between two decades was revealed. In the 1990s, statistically more Stage B patients were found than those in 1980s. In addition, databases show a significant decrease in the Stage D cases. The proportion of adenocarcinoma increased, but the mucinous adenocarcinoma decreased during two decades. CONCLUSION: These findings indicate that the pattern of colorectal cancer in China has been changing. Especially, a proximal shift due to the increasing proportion of ascending and transverse colon cancer has occurred in China. 展开更多
关键词 Colorectal carcinoma Time trends Age SEX Subsite PATHOLOGY
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A Comprehensive Evaluation of Tourism Climate Suitability in Qinghai Province, China 被引量:11
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作者 TANG Chengcai ZHONG Linshen +1 位作者 KRISTEN McDonald CHENG Shengkui 《Journal of Mountain Science》 SCIE CSCD 2012年第3期403-413,共11页
Qinghai Province is an important component of the Qinghai-Tibet Plateau in China. Scientific evaluation of the suitability of Qinghai's climate for tourism can contribute to overcoming obstacles posed by climate o... Qinghai Province is an important component of the Qinghai-Tibet Plateau in China. Scientific evaluation of the suitability of Qinghai's climate for tourism can contribute to overcoming obstacles posed by climate on sustainable tourism development in Qinghai Province, including disparities between the low and high seasons, high altitude health concerns, and weather events. A tourism climate suitability evaluation model of the Qinghai-Tibet Plateau is constructed (Tourism Climate Suitability Index, or TCSI), and tourism climate suitability is comprehensively evaluated for Qinghai Province from climate data from 1960 to 2009. Results show that: (I) There is clear distributional characteristics of spatial-temporal variability of TCSI values in Qinghai Province. (II) Tourism climate suitability in Qinghai Province has significant seasonal and regional differences. The year is divided into a very suitable period (July and August), suitable tourism periods (from April and October), less suitable periods (From Nov to Mar). June to August is the most suitable tourism period in Qinghai. Qinghai Province is divided into five levels of tourism climate suitability: most suitable regions, very suitable regions, suitable regions, less suitable regions, and unsuitable region. (III) The key factor which influences regional differences in tourism climatic suitability is atmospheric oxygen. And the key factors which chiefly influence seasonal differences of tourism climate suitability are temperature and humidity, the wind chill factor, and barrier weather. 展开更多
关键词 Tourism climate Tourism climatesuitability index (TCSI) Comprehensive evaluation Qinghai Province Qinghai-Tibet Plateau China
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Glacier Extent and Volume Change(1966~2000) on the Su-lo Mountain in Northeastern Tibetan Plateau,China 被引量:10
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作者 WANG Yetang HOU Shugui +2 位作者 HONG Sungmin HUR Soon Do LIU Yaping 《Journal of Mountain Science》 SCIE CSCD 2008年第4期299-309,共11页
The topographic maps of 1:50,000 scales,aerial photographs taken in 1966,one Landsat image taken in 1999,and SRTM data from 2000 were used to quantify the losses in area and volume of the glaciers on the Su-lo Mountai... The topographic maps of 1:50,000 scales,aerial photographs taken in 1966,one Landsat image taken in 1999,and SRTM data from 2000 were used to quantify the losses in area and volume of the glaciers on the Su-lo Mountain,in the northeastern Tibetan Plateau,China in the past 30 years.The total glacier area decreased from 492.9km2 in 1966 to 458.2km2 in 1999.The volume loss of the studied glaciers reached 1.4 km3 from 1966 to 2000.This agrees with documented changes in other mountain glaciers of the whole Tibetan Plateau. 展开更多
关键词 Glacier change Su-lo Mountain ETM +image Tibetan Plateau China
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Studies on frozen ground of China 被引量:29
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作者 赵林 程国栋 丁永建 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期411-416,共6页
Permafrost in China includes high latitude permafrost in northeastern China, alpine permafrost in northwestern China and high plateau permafrost on the Tibetan Plateau. The high altitude permafrost is about 92% of the... Permafrost in China includes high latitude permafrost in northeastern China, alpine permafrost in northwestern China and high plateau permafrost on the Tibetan Plateau. The high altitude permafrost is about 92% of the total permafrost area in China. The south boundary or lower limit of the seasonally frozen ground is defined in accordance with the 0 ℃ isothermal line of mean air temperature in January, which is roughly corresponding to the line extending from the Qinling Mountains to the Huaihe River in the east and to the southeast boundary of the Tibetan Plateau in the west. Seasonal frozen ground occurs in large parts of the territory in northern China, including Northeast, North, Northwest China and the Tibetan Plateau except for permafrost regions, and accounting for about 55% of the land area of China. The southern limit of short-term frozen ground generally swings south and north along the 25° northern latitude line, occurring in the wet and warm subtropic monsoon climatic zone. Its area is less than 20% of the land area of China. 展开更多
关键词 PERMAFROST frozen ground China
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Six New Species of Sawflies from Gansu and Qinghai Provinces of China (Hymenoptera: Tenthredinidae) 被引量:6
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作者 Attila Haris 《Zoological Research》 CAS CSCD 北大核心 2009年第3期319-326,共8页
Three new Tenthredinidae species are reported from Gansu and three from Qinghai Provinces of China. Tenthredo (Tenthredo) sinotemula sp. nov., Tenthredo (Tenthredella) labrangensis sp. nov. and Tenthredo (Tenthre... Three new Tenthredinidae species are reported from Gansu and three from Qinghai Provinces of China. Tenthredo (Tenthredo) sinotemula sp. nov., Tenthredo (Tenthredella) labrangensis sp. nov. and Tenthredo (Tenthredella) sinosimplex sp. nov. are described from Gansu, Tenthredo (Tenthredella) rolleri sp. nov., Tenthredo (Tenthredella) qinghaiensis sp. nov. and Tenthredo (Tenthredella) yunningsiensis sp. nov. from Qinghai Province. 展开更多
关键词 HYMENOPTERA Symphyta TENTHREDINIDAE New species. Gansu QINGHAI China
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Long-term Activity of Earthquake-induced Landslides: A Case Study from Qionghai Lake basin, Southwest of China 被引量:10
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作者 WEI Xue-li CHEN Ning-sheng +3 位作者 CHENG Qian-gong HE Na DENG Ming-feng TANOLI Javed Iqbal 《Journal of Mountain Science》 SCIE CSCD 2014年第3期607-624,共18页
Earthquake-triggered landslides are a major geological hazard in the eastern Tibetan Plateau, and have prolonged impact on earth surface processes and fluvial system. To determine how long co-seismic landslides affect... Earthquake-triggered landslides are a major geological hazard in the eastern Tibetan Plateau, and have prolonged impact on earth surface processes and fluvial system. To determine how long co-seismic landslides affect basins, a massive number of landslides existing in Qionghai Lake Basin were investigated for landslide distribution characteristics and geomorphological evidences, with further comparison and analysis using historic seismic analog method. The landslides found in Qionghai Lake Basin showed clear features of seismic triggering with strongly controlled by Zemuhe fault. These landslides are still active at present. Some new slides generally occur in ancient slope failure zones causing serious secondary hazards in recent years. In this study we strengthen the idea that the landslides triggered by the 185o Xichang earthquake (Ms7.5) have long term activity and prolonged impact on the mountain disasters with a period of more than 16o years. Our results support growing evidence that coseismic landslides have a prolonged effect on secondary disasters in a basin, and invite more careful consideration of the relationship between current basin condition and landslide history for a longer period. 展开更多
关键词 Qionghai Lake EARTHQUAKE LANDSLIDE Debris flow Sediment yield
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Correlation of Dust Storms in China with Chlorophyll a Concentration in the Yellow Sea between 1997-2007 被引量:3
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作者 TAN Sai-Chun 1,2 and SHI Guang-Yu 1 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China 2 Key Laboratory of Meteorological Disaster of Ministry of Education,Nanjing University of Information Science and Technology,Nanjing 210044,China 《Atmospheric and Oceanic Science Letters》 2012年第2期140-144,共5页
Based on daily observation data at 222 meteorological stations in China,the characteristics of dust storms between 1997 and 2007 were examined.Next,the relationship between dust events and chlorophyll (Chl) a concentr... Based on daily observation data at 222 meteorological stations in China,the characteristics of dust storms between 1997 and 2007 were examined.Next,the relationship between dust events and chlorophyll (Chl) a concentration in the Yellow Sea was investigated.There were six regions with high annual frequencies of dust storms.The seasonal distribution of dust storms showed spatiotemporal variation.The six regions with highest annual frequencies also exhibited high frequencies of dust storms in spring.Dust storms in most regions occurred in spring.Of all dust storms in China,sixty-five percent of all dust storms occurred during the spring.The area and frequency of dust storms were smaller in fall and winter than in spring and summer.A significant correlation was found between dust events and Chl a concentration in the Yellow Sea.High correlation regions included Qinghai-Xizang region,part of the Hexi Corridor,the western Inner Mongolia and Hetao Regions,and the Hunshandake Desert.The high correlation may be induced by the high ratio of dust storms in the abovementioned regions that arrive over the Yellow Sea,as inferred through a forward trajectory analysis;especially notable is dust transported at a lower altitude (< 3 km). 展开更多
关键词 dust storm spatial distribution seasonal variation CHLOROPHYLL Yellow Sea
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The advertisement call of the giant spiny frog Paa spinosa 被引量:12
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作者 Baogen YU Rongquan ZHENG 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第6期411-415,共5页
We analyzed the advertisement call of Paa spinosa at Yuliang Mountain,Lanxi,Zhejiang Province,in eastern China.Temporal and spectral call parameters were analyzed,along with call intensity.Calls comprised of three to ... We analyzed the advertisement call of Paa spinosa at Yuliang Mountain,Lanxi,Zhejiang Province,in eastern China.Temporal and spectral call parameters were analyzed,along with call intensity.Calls comprised of three to seven notes,the last of which had the longest duration.Three formants(harmonics)were clearly distinguishable from the audio spectrogram.The dominant frequency ranged from 411-1534 Hz,and was either the first or the second formant.The number of notes within a call was positively correlated to air temperature,so that calls contained more notes during the day.Also,the dominant frequency appeared to be lower at the highest temperature. 展开更多
关键词 Advertisement call ANURA Paa spinosa TEMPERATURE
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The influence of plant root system architectural properties upon the stability of loess hillslopes,Northeast Qinghai,China 被引量:22
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作者 FU Jiang-tao HU Xia-song +5 位作者 BRIERLEY Gary QIAO Na YU Qin-qin LU Hai-jing LI Guo-rong ZHU Hai-li 《Journal of Mountain Science》 SCIE CSCD 2016年第5期785-801,共17页
To investigate the influence of root system architectural properties of three indigenous (cold- adapted) shrubs on the hillslope stability of loess deposits in the Xining Basin, northeast part of Qinghai-Tibet Plate... To investigate the influence of root system architectural properties of three indigenous (cold- adapted) shrubs on the hillslope stability of loess deposits in the Xining Basin, northeast part of Qinghai-Tibet Plateau (QTP), indoor direct shear tests have been conducted on the remolded rooted soil of three shrubs. Test results show that root system architectural indices (root area ratio (RAR), root length density (RLD) and root density (RD)) of the shrubs decline with depth and the relationship between RAR, RD and depth is exponential, while a power relationship describes the relationship between RLD and depth. The cohesion force of remolded rooted soil for the shrubs initially increases with depth, but it then demonstrates a slightly decreasing trend, which can be described with a power relationship. Power relationships also describe relationships between cohesion force and RAR, RLD and RD for the shrubs. As the growth period increases from lO to 17 months, the incremental increase in RAR is 48.32% ~ 21o.25% for Caragana korshinskii Kom and 0.56% ~ 166.85% for ZygophyUum xanthoxylon (Bunge) Maxim. This proportional increase is notably larger than that for RLD and RD. The increment in RAR is marginally greater for C. korshinskff than it is for Z. xanthoxylon. Correspondingly, the cohesion force incremental rates of remolded rooted soil for C. korshinskii and Z. xanthoxylon are 12.41% ~ 25.22% and 3.45% ~ 17.33% respectively. Meanwhile, as root content increases, the contribution by roots to cohesion force increases markedly until a threshold condition is reached. 展开更多
关键词 Cold region Semiarid region Soil reinforcement Hillslope stability Root system architectural indices Plateau
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Increasing prevalence of advanced colonic polyps in young patients undergoing colonoscopy in a referral academic hospital in Hong Kong 被引量:1
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作者 Tze Jui Lam Benjamin CY Wong +4 位作者 Chris JJ Mulder A Salvador Pea Wai Mo Hui Shiu Kum Lam Annie On On Chan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第28期3873-3877,共5页
AIM: To investigate the distribution and frequency of advanced polyps over eight years.METHODS:6424 colonoscopies were reviewea aunng the study period 1998 to 2005. The study period was subdivided into period I : 1... AIM: To investigate the distribution and frequency of advanced polyps over eight years.METHODS:6424 colonoscopies were reviewea aunng the study period 1998 to 2005. The study period was subdivided into period I : 1998 to 2001 and period 11: 2002-2005. RESULTS: 1856 polyps (33% advanced polyps) and 328 CRCs were detected. The mean ages of the patients with advanced polyps and cancer were 69.2 ± 12.0 and 71.6± 13.8 years, respectively. Advanced polyps were mainly lerc sided (59.5%). Advanced polyps were found in patients ≤60 years from 17.7% in period Ⅰto 26.3% in period Ⅱ(P 〈 0.05), especially in male subjects ≤60 years (21.6% vs 31.6%, P 〈 0.05). Advanced tubuloviUous polyps rose from 21.5% in period I to 29.5% in period Ⅱ (P 〈 0.05). Whereas cancers in male patients ≤ 60 years were similar in both periods: 23.2% vs 16.5% (P 〉 0.05).CONCLUSION: Advanced polyps increased significantly in the younger male group in the most recent period and there seems to be a shiE towards a proximal location. 展开更多
关键词 Colonic polyps COLONOSCOPY Chinese
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Characteristics of the microzooplankton community in Jiaozhou Bay,Qingdao,China 被引量:6
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作者 陈应华 杨宇峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期435-442,共8页
The species composition and abundance of microzooplankton at 10 marine and five coastal stations (Hongdao, Daguhe, Haibohe, Huangdao and Hangxiao) in the Jiaozhou Bay (Qingdao, China) were studied in 2001. The mic... The species composition and abundance of microzooplankton at 10 marine and five coastal stations (Hongdao, Daguhe, Haibohe, Huangdao and Hangxiao) in the Jiaozhou Bay (Qingdao, China) were studied in 2001. The microzooplankton community was found to be dominated by Tintinnopsis beroidea, Tintinnopsis urnula, Tintinnopsis brevicoUis and Codonellopsis sp. The average abundance of microzooplankton was highly variable among stations. Specifically, the abundance of microzooplankton was higher at inshore stations and lower in the center of the bay (St. 5), bay mouth (St. 9) and outside the bay (St. 10). The highest average annual densities (346 ind./L) was observed at St. 3, while the lowest (55 ind./L) was at St. 10. Two abundance peaks were recorded in May (324 ind./L) and February (300 ind./L). The distribution of microzooplankton in three sampling layers at the 10 stations was relatively homogenous and the abundance decreased slightly as the water depth increased. At coastal stations, the highest average annual density was recorded at Hongdao Station (677 ind./L), followed by Daguhe Station (616 ind./L), Haibohe Station (400 ind./L ), Huangdao Station (275 ind./L) and Hangxiao Station (73 ind./L). Furthermore, a 24-h sampling analysis conducted at Hangxiao Station revealed that the microzooplankton assemblages were characterized by a bimodal diel vertical migration pattem, with the highest densities occurring at dusk (154 ind./L), followed by dawn (146 ind./L), noon (93 ind./L) and midnight (77 ind./L). The density of microzooplankton in the Jiaozhou Bay was in the middle range of the densities of temperate coastal waters worldwide. 展开更多
关键词 Jiaozhou Bay MICROZOOPLANKTON species composition abundance distribution
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Applications of Three DNA Barcodes in Assorting Intertidal Red Macroalgal Flora in Qingdao, China 被引量:7
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作者 ZHAO Xiaobo PANG Shaojun +1 位作者 SHAN Tifeng LIU Feng 《Journal of Ocean University of China》 SCIE CAS 2013年第1期139-145,共7页
This study is part of the endeavor to construct a comprehensive DNA barcoding database for common seaweeds in China. Identifications of red seaweeds, which have simple morphology and anatomy, are sometimes difficult s... This study is part of the endeavor to construct a comprehensive DNA barcoding database for common seaweeds in China. Identifications of red seaweeds, which have simple morphology and anatomy, are sometimes difficult solely depending on morphological characteristics. In recent years, DNA barcode technique has become a more and more effective tool to help solve some of the taxonomic difficulties. Some DNA markers such as COI(cytochrome oxidase subunit I) are proposed as standardized DNA barcodes for all seaweed species. In this study, COI, UPA (universal plastid amplicon, domain V of 23S rRNA), and ITS (nuclear internal transcribed spacer) were employed to analyze common species of intertidal red seaweeds in Qingdao (119.3°-121°E, 35.35°-37.09°N). The applicability of using one or a few combined barcodes to identify red seaweed species was tested. The results indicated that COI is a sensitive marker at species level. However, not all the tested species gave PCR amplification products due to lack of the universal primers. The second barcode UPA had effective universal primers but needed to be tested for the effectiveness of resolving closely related species. More than one ITS sequence types were found in some species in this investigation, which might lead to confusion in further analysis. Therefore ITS sequence is not recommended as a universal barcode for seaweeds identification. 展开更多
关键词 red seaweeds DNA barcoding COI ITS UPA
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Planation Surfaces on the Tibet Plateau,China 被引量:2
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作者 ZHANG Xinbao HE Xiubin +1 位作者 WANG Yangchun LONG Yi 《Journal of Mountain Science》 SCIE CSCD 2008年第4期310-317,共8页
A planation hypothesis is proposed to explain landform evolution of the Tibet Plateau. A denudation threshold (T), the maximum potential denudation rate for a certain type of rock, is introduced to explain the combi... A planation hypothesis is proposed to explain landform evolution of the Tibet Plateau. A denudation threshold (T), the maximum potential denudation rate for a certain type of rock, is introduced to explain the combined effects of lithology and tectonics on landform evolution. If the tectonic uplifting rate (U) is equal to or less than the threshold rate (U ≤ T), the tectonic uplifting and terrain denudation are in dynamic equilibrium, and landforms are in a steady state. The end product should be planation surfaces whether the original landforms are flat plains or deeply dissected mountains. If U 〉 T, uplift and denudation are not able to reach a dynamic equilibrium state. The plateau surface is mostly underlain by soft rocks, such as the Mesozoic epimetamorphic argillites and Tertiary sedimentary rocks, while the mountain ranges comprise hard rocks, such as granite, gneiss and limestone. In soft rock regions, hills are low with a relative relief of mostly less than 100 m and the slopes are gentle at a gradient of 〈200. In contrast, hills can maintain steep slopes in hard rock regions. The Tibet Plateau has been under an equilibrium condition between tectonic uplifting and denudation except for the mountain ranges. The plateau might have reached the present altitudes before the Quaternary. 展开更多
关键词 planation denudation threshold landform evolution Tibet Plateau China
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Taxonomic Studies on a New Marine Ciliate, Apocoleps magnus gen. nov., spec. nov. (Ciliophora, Colepidae), Isolated from Qingdao, China 被引量:1
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作者 CHEN Xiangrui Alan Warren SONG Weibo 《Journal of Ocean University of China》 SCIE CAS 2009年第4期317-321,共5页
The morphology and infraciliature of a new marine colepid ciliate, A'pocoleps magnus gen. nov., spec. nov., are de- scribed based on living observations and silver impregnations. The new genus Apocoleps is characteri... The morphology and infraciliature of a new marine colepid ciliate, A'pocoleps magnus gen. nov., spec. nov., are de- scribed based on living observations and silver impregnations. The new genus Apocoleps is characterized by having 8 (vs. 6 in most other related genera) armour tiers, spines at both ends of the cell, 3 adoral organelles and plates with 4 reniform uni-windows. Apo- coleps magnus spec. nov. is defined by the following features: body elongated and slightly curved, about 100-120p.mx 3545 lam in vivo; anterior tertiary tier plate with four uni-windows, most secondary and main tier plates with four uni-windows, posterior tertiary tier plate with two uni-windows; left plate margin slightly serrated; on average 23 transverse and 22 longitudinal ciliary rows; one terminal contractile vacuole; marine habitat. 展开更多
关键词 marine ciliates new genus new species taxonomy
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Antioxidant Activity of Isothiocyanate Extracts from Broccoli 被引量:5
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作者 袁海娜 姚善泾 +2 位作者 尤玉如 肖功年 尤琦 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期312-321,共10页
Isothiocyanates(ITCs) extracts were prepared from fresh broccoli.Their antioxidant properties were evaluated by using the in vitro bioassays,including superoxide anion radical( 2 O·-) ,hydroxyl radical(HO·-)... Isothiocyanates(ITCs) extracts were prepared from fresh broccoli.Their antioxidant properties were evaluated by using the in vitro bioassays,including superoxide anion radical( 2 O·-) ,hydroxyl radical(HO·-) and 2,2-diphenyl-1-picrylhydracyl(DPPH·) radical-scavenging methods,lipid peroxidation assay,and reducing power assay.The ITCs extracts exhibited significant dose-dependent antioxidant activities(P<0.01) .Its antioxidant-stability was affected by temperature and storage condition,although it was more stable than vitamin C(Vc) .GC-MS iden-tified sulforaphane in the ITCs extracts.The antioxidant activity of sulforaphane was approximately one tenth to one fifth of that of Vc.Sulforaphane was experimented to be one of dominating contributors to antioxidant capacity of ITCs extracts.However,there was no direct antioxidant activity found for benzyl isothiocyanate(BITC) in vitro. Therefore,it could be concluded that the general group(-N=C=S) was not the essential part for the antioxidant activity of sulforaphane.It is suggested that the ITCs extracts from broccoli can be developed into a promising food additive for healthy food. 展开更多
关键词 antioxidant activity ISOTHIOCYANATES BROCCOLI SULFORAPHANE
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Biomass and carbon storage of Gracilariopsis lemaneiformis(Rhodophyta) in Zhanshan Bay, Qingdao, China 被引量:1
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作者 周伟 隋正红 +6 位作者 王津果 胡依依 康庆浩 吴俊映 金相澈 黄建辉 王朋云 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1009-1015,共7页
Marine macroalgae can absorb carbon and play an important role in carbon sequestration. As an important economic macroalga, Gracilariopsis lemaneiformis has the potential to significantly affect carbon absorption and ... Marine macroalgae can absorb carbon and play an important role in carbon sequestration. As an important economic macroalga, Gracilariopsis lemaneiformis has the potential to significantly affect carbon absorption and storage in wave-sheltered intertidal reef systems. However, detailed knowledge on seasonal biomass changes and carbon storage of G. lemaneiformis is lacking, especially in many small and scattered ecosystems. Considering the influence of human activities on wild distribution of G. lemaneiformis, the understanding of seasonal dynamics of an economically important species in nature is necessary. In this study, we first investigated seasonal variations in biomass, coverage area, and carbon storage during low tide from August 2011 to July 2012 in Zhanshan Bay, Qingdao, China. Furthermore, we estimated the carbon storage potential of wild G. lemaneiformis using light use efficiency (LUE). The results show that the standing biomass and coverage area changed significantly with season. However, seasonal variations in carbon content and water content were not obvious, with an average content of 35.1% and 83.64%, respectively. Moreover, carbon storage in individual months varied between 0.67 and 47.03 g C/mE, and the value of carbon storage was the highest in August and June and the lowest in February. In Zhanshan Bay, LUE of G. lemaneiformis was only 0.23%. If it is increased to the theoretical maximum (5%-6%), the carbon storage will have an increase of at least 21 times compared with the current, which suggested that carbon storage of wild G. lemaneiformis had a high enhancement potential. The study will help to assess a potential role of G. lemaneiformis in reducing atmospheric CO2 展开更多
关键词 carbon storage GRACILARIA Gracilariopsis lemaneiformis standing biomass Qingdao
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Performance comparison of permafrost models in Wudaoliang Basin,Qinghai-Tibet Plateau,China 被引量:3
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作者 YIN Guo-an NIU Fu-jun +2 位作者 LIN Zhan-ju LUO Jing LIU Ming-hao 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1162-1173,共12页
Knowledge of the spatial distribution of permafrost and the effects of climate on ground temperature are important for land use and infrastructure development on the Qinghai-Tibet Plateau(QTP). Different permafrost mo... Knowledge of the spatial distribution of permafrost and the effects of climate on ground temperature are important for land use and infrastructure development on the Qinghai-Tibet Plateau(QTP). Different permafrost models have been developed to simulate the ground temperature and active layer thickness(ALT). In this study, Temperature at Top of Permafrost(TTOP) model, Kudryavtsev model and modified Stefan solution were evaluated against detailed field measurements at four distinct field sites in the Wudaoliang Basin to better understand the applicability of permafrost models. Field data from 2012 to 2014 showed that there were notable differences in observed ground temperatures and ALTs within and among the sites. The TTOP model is relatively simple, however, when driven by averaged input values, it produced more accurate permafrost surface temperature(Tps) than the Kudryavtsev model. The modified Stefan solution resulted in a satisfactory accuracy of 90%, which was better than the Kudryavtsev model for estimating ALTs. The modified Stefan solution had the potential of being applied to climate-change studies in the future. Furthermore, additional field investigations over longer periods focusing on hydrology, which has significant influence on permafrost thaw, are necessary. These efforts should employ advanced measurement techniques to obtain adequate and extensive local parameters that will help improve model accuracy. 展开更多
关键词 Permafrost model Active layer thickness Soil freeze-thaw Soil temperature
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Height and weight are correlated with lumbar spinal bone mineral contents and densities in Chinese adolescents with early ankylosing spondylitis
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作者 马兴 胡蕴玉 +5 位作者 马向东 王全平 李晓娟 吕荣 王军 徐新智 《Journal of Medical Colleges of PLA(China)》 CAS 2004年第3期190-193,共4页
Objective: To explore the possible factors influencing lumbar spinal bone mineral contents and bone mineral densities in Chinese adolescents with early ankylosing spondylitis(AS). Methods: Thirty-one male Chinese adol... Objective: To explore the possible factors influencing lumbar spinal bone mineral contents and bone mineral densities in Chinese adolescents with early ankylosing spondylitis(AS). Methods: Thirty-one male Chinese adolescent outpatients with early AS were included and compared with 31 age-matched male controls. Age (year), height (cm), total body weight (kg) together with body mass index (BMI, kg/m 2) of all subjects and disease duration (month), BASMI, BASFI, BASDAI, SASSS as well as ESR (mm/h) of AS patients were obtained. Lumbar 2-4 bone mineral content (L 2-4BMC, g) and lumbar 2-4 areal bone mineral density (L 2-4 BMD, g/cm 2) were evaluated using dual-energy X-ray absorptiometry (DEXA) with Lunar DPX-IQ device and lumbar 2-4 volumetric bone mineral apparent density (L 2-4 BMAD, g/cm 3) was subsequently calculated. Correlation and multiple regression analyses were performed. Results: Compared with 31 age-matched male controls, AS patients had significantly lower L 2-4BMD [(0.984±0.142) g/cm 2 vs (1.055±0.137) g/cm 2, P=0.049] and L 2-4BMAD [(0.1527±0.0173) g/cm 3 vs (0.1630±0.0195) g/cm 3, P=0.032]. In AS patients, multiple regression analysis identified that only the factor of height was significantly correlated with L 2-4BMC (R=0.673, P=0.000) and the factor of weight had predominant influences on L 2-4BMD (R=0.620, P=0.000) as well as L 2-4BMAD (R=0.510, P=0.003). Conclusion: The young patients with early AS had marked reduction in lumbar spine bone mineral densities, which indicated an important primary event leading to osteoporosis. Positive effects of height and weight on lumbar spine bone mass and densities could expectantly make favorable contributions to early prevention of AS associated bone loss and subsequent osteoporosis. 展开更多
关键词 ADOLESCENCE ankylosing spondylitis bone mineral density height OSTEOPOROSIS weight
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Quaternary glacio-erosional landforms in Laoshan Mountain and their constraints on the origin of Jiaozhou Bay, Qingdao, east of China 被引量:9
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作者 吕洪波 颜世永 张跃 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第2期139-148,共10页
A field investigation on Quaternary glacial landforms in Laoshan Motmtain has discovered many glacial potholes, scouring grooves on top of granite ridges, and large boulders. These erosional landforms were formed by t... A field investigation on Quaternary glacial landforms in Laoshan Motmtain has discovered many glacial potholes, scouring grooves on top of granite ridges, and large boulders. These erosional landforms were formed by the meltwater from the overlying ice cap, suggesting that there was at least an ice cap covering Laoshan Mountain and the surrounding areas or even a continental ice sheet over the vast area of Shandong Province in the Late Pleistocene. The ice sheet was obstructed by the Laoshan Mountain, Dazhu Mountain and Xiaozhu Mountain in the coastal areas as it moved toward the Yellow Sea. The ice flows eroded the bedrock and carved the weak intersection of the fault systems in the NE and NW directions into a deep channel, which gradually formed a fjord in the area of the Jiaozhou Bay basin by 20.00 ka BE The seawater gradually invaded the fjord from the beginning of the Holocene (11.00 ka BP) and Jiaozhou Bay was eventually formed. Similar fjords are easily found along the east of China and they share a similar origin because of the Quaternary glaciation in the region. 展开更多
关键词 Quaternary glaciation LANDFORM Mount Laoshao Jiaozhou bay Eastern China
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