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The Process of Tiger Disappearance in Guizhou
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作者 Qin Yang Cheng Xu +1 位作者 Qingqing He Lingling Deng 《Research in Ecology》 CAS 2024年第1期28-39,共12页
In this paper,the authors collected officially published literature on the South China tiger(Panthera tigris amoyensis)in Guizhou from 1900 to 1980,from which we extracted information on its historical distribution an... In this paper,the authors collected officially published literature on the South China tiger(Panthera tigris amoyensis)in Guizhou from 1900 to 1980,from which we extracted information on its historical distribution and population size,and collected data on the tiger skin trade after 1950,the change in subtropical broad-leaved evergreen forest cover,and demographic data in the relevant databases.GIS mapping was used to visualize the distribution range of the South China tiger in Guizhou Province during the period 1900–1980 and to discuss the history of its disappearance in Guizhou and its driving factors.The results show that in 1900,the South China tiger was distributed throughout 82 cities and counties in nine prefectures and municipalities in the province;the number of documented South China tiger distribution sites in 1900–1950 decreased to 48 compared to 1900;the number of counties with South China tigers in 1950–1980 further decreased and became extinct in some areas;and in the 1990s,the South China tiger became extinct in the wild in Guizhou.The main reasons for the extinction of the South China tiger in the wild in Guizhou are:on the one hand,with the socio-economic development of Guizhou Province,the population has increased dramatically,the magnitude of the demand for natural resources has increased,and in order to satisfy this demand,human activities,such as coal mining and clearing of mountains for planting,have been intensified,resulting in the reduction of the coverage rate of the subtropical broad-leaved evergreen forests,which has resulted in the extreme loss of the habitat of the South China tiger;on the other hand,the insufficient protection efforts and protection measures for this species in the country before the 1980s,which were subjected to anthropogenic hunting,were also factors leading to the extinction of this species in the wild in Guizhou Province.As a big cat at the top of the food chain,the distribution of the South China tiger can reflect the history of the natural environment in the region.By analyzing and discussing the distribution history of the South China tiger population in Guizhou Province,the significance of this case is to provide a scientific basis for the future conservation of biodiversity and the development of ecological restoration measures in the karst mountains of southern China. 展开更多
关键词 The South China tiger disappearANCE Broad-leaved evergreen forests
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Who is in the Lower Reaches,Who Suffers Disasters?——Take Minqin County,a Disappearing Oasis as a Case 被引量:3
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作者 Bao Chao Fang Chuanglin 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第2期41-46,共6页
Minqin Oasis is located in the lower reaches of the Shiyanghe River Basin, northeast of the Heixi Corridor, at the middle of the Silk Road. Because of the its existence, Badain Jaran Desert and Tengger Desert cannot c... Minqin Oasis is located in the lower reaches of the Shiyanghe River Basin, northeast of the Heixi Corridor, at the middle of the Silk Road. Because of the its existence, Badain Jaran Desert and Tengger Desert cannot converge and develop in the south. It has always been an important green barrier to guarantee the eco-security of Hexi Corridor and the Silk Road for thousands of years. But in recent decades, Minqin Oasis is becoming smaller and the desert is becoming larger. Many people, especially the governmental officials in the lower reaches think that the upper and middle reaches have robbed the lower reaches of water resources, and caused insufficient water usage and the deteriorated eco-environment, in the lower reaches, However, the governmental officials in the upper and middle reaches claim that the whole river basin should take the upper and middle reaches as the key regions to develop economy. To address the above argument, we analyze the reasons why Minqin Oasis is disappearing, and find that there are two main factors. One is the quick development of population and economy in the upper and middle reaches; the other is the rapid development of population and economy in the lower reaches. The two factors both have great effect on the water utilization for eco-environment in the lower reaches. So Minqin Oasis is disappearing not only because of the upper and middle reaches but also because of the growth of population and economy itself. The lower reaches should not completely blame the upper and middle reaches. The upper and middle reaches should also pay more attention to the eco-environment in the lower reaches. The whole river basin should develop a harmonious and sustainable relationship among the upper, middle and lower reaches. 展开更多
关键词 disappearing oasis water dispute spatial optimization Minqin Oasis
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DISAPPEARANCE OF INTERFACES FOR DEGENERATE PARABOLIC EQUATIONS WITH VARIABLE DENSITY AND ABSORPTION 被引量:2
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作者 胡学刚 穆春来 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期735-742,共8页
In this article, the authors deal with the Cauchy problem of a nonlinear parabolic equation with variable density and absorption. By using energy methods, the authors prove that the interfaces can disappear in finite ... In this article, the authors deal with the Cauchy problem of a nonlinear parabolic equation with variable density and absorption. By using energy methods, the authors prove that the interfaces can disappear in finite time under some assumptions on the density functions. 展开更多
关键词 disappearance of interface degenerate parabolic equation variable density absorption
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Reading Text Under Normal and Disappearing Presentation Conditions 被引量:2
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作者 Simon P. Liversedge 《心理与行为研究》 2004年第3期505-512,共8页
In this article I discuss data from a series of experiments in which readers’ eye movements were recorded as they processed sentences in which each word disappeared or was masked 60ms after fixation onset. We used th... In this article I discuss data from a series of experiments in which readers’ eye movements were recorded as they processed sentences in which each word disappeared or was masked 60ms after fixation onset. We used this paradigm to investigate whether we could induce a gap effect during reading, and how visual and linguistic factors affected eye movements under these conditions. The data showed that no gap effect occurred in our experiment. Overall reading times were the same under normal and disappearing presentation conditions. However, readers did adopt a strategy of making fewer but longer fixations when the text disappeared than when it did not. Additionally, clear frequency effects occurred regardless of whether the text was presented normally or disappeared. This finding indicates that while the visual uptake of information is important, cognitive processes associated with the lexical identification of words are a primary influence on when readers move their eyes during reading. The findings are taken to support the E-Z Reader model of eye movement control. 展开更多
关键词 eye movements disappearing TEXT reading.
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Disappearance of unaffected motor cortex activation by repetitive transcranial magnetic stimulation in a patient with cerebral infarct 被引量:1
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作者 Jeong Pyo Seo Sung Ho Jang 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第7期761-762,共2页
The ipsilateral motor pathway from the unaffected motor cortex to the affected extremity is one of the motor recovery mechanisms following stroke (Jang, 2011). Because stroke patients who had shown recovery by this ... The ipsilateral motor pathway from the unaffected motor cortex to the affected extremity is one of the motor recovery mechanisms following stroke (Jang, 2011). Because stroke patients who had shown recovery by this mechanism usually showed poorer motor function, compared with patients who showed recovery by other mechanisms, several researchers have considered this mechanism as a maladaptive plasticity (]ang, 2013). 展开更多
关键词 disappearance of unaffected motor cortex activation by repetitive transcranial magnetic stimulation in a patient with cerebral infarct MCA
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Disappearance of Flow as a Function of Impact Parameter for ^(64)Zn+^(58)Ni Collisions at Intermediate Energies 被引量:1
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作者 He Zhi-yong Dai Guang-xi Jin Gen-ming Zhang Feng-shou (Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000)Shen Wen-qing Ma Yu-gang (Institute of Nuclear Research,Chinese Academy of Sciences,Shanghai 201800) 《Chinese journal of nuclear physics》 1994年第4期313-316,共4页
The disappearance of collective flow for <sup>64</sup>Zn+<sup>58</sup>Ni collisions is studied withBUU equation.It is found that the balance energy,E<sub>bal</sub>,is very sensitive... The disappearance of collective flow for <sup>64</sup>Zn+<sup>58</sup>Ni collisions is studied withBUU equation.It is found that the balance energy,E<sub>bal</sub>,is very sensitive to the in-me-dium nucleon-nucleon cross section and increases with the impact parameter. 展开更多
关键词 BUU equation Impact PARAMETER disappearANCE of FLOW BALANCE energy
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Prosperity and Disappearance of Introduced Fishes in Xiangmoshan Reservoir
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作者 FAN Zhaoting CHEN Weixing LIU Yi FANG Jingjie LIU Qingzhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期29-37,共9页
In order to enhance the resources, some fishes were introduced into Xiangmoshan reservoir. The introduced fishes consisted of different ecotypes such as silver carp (Hypophthahnichthys rnolitrix (Cuvier et Valencien... In order to enhance the resources, some fishes were introduced into Xiangmoshan reservoir. The introduced fishes consisted of different ecotypes such as silver carp (Hypophthahnichthys rnolitrix (Cuvier et Valenciennes)), big head (Aristichthys nobilis (Richardso)) and lake herring (Coregonus clupeaformis (Mitchill)) that were plankton feeders, common carp (Cyprinus carpio Linnaeus) and crucian carp (Carassius auratus gibelio) belonging to the polyphagia, and also the non-native predator Walleye (Stizostedion vitreum (Mitchill)) and big mouth (Silurus soldatovi rneridonalis Chen), et al. Among there were not only the cool water fish Peled (Coregonus peled (Gmelin)), but also the warm water fish big mouth. The introduction of non-native fishes resulted in ecosystem changes of the reservoir and some native fishes had gone to decrease their population sizes or been in the condition of depopulation such as Opsariichthys uncirostris arnurensis (Berg), Rhodeus sericeus (Pallas) and Silurus asotus (Linnaeus). The native common carp had disappeared after the introduction of non-native species. Roach (Rutilus rutilus lacustris (Pallas) had been thriven for one or two generations after its introduction and immeidiatly disappeared. Silver fish (Protosalanx hyalocranius (Abbott)), Lake herring (Coregonus clupeaformis (Mitchill)) and Walleye (Stizostedion vitreum (Mitchill)) died several years after the introduction, so most of the introduced species has passed out of existence. Via many years introduction of different fishes, composition of species and the structure of the population in the reservoir had been changed obviously. It was necessary to further estimate whether the ecosystem of the reservoir had been damaged. 展开更多
关键词 Xiangmoshan reservoir introdued fish prosperity and disappearance ecological damage
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Ruminal in situ disappearance kinetics of six nutritive ingredients in leaves and stems of young tetraploid black locust in growing steers
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作者 JIANG Jin-zhong SUN Peng +4 位作者 LI Yun ZHANG Guo-jun LIU Jian-hua HAN Feng-bao NIU Chen 《Forestry Studies in China》 CAS 2009年第3期168-173,共6页
Tetraploid black locust (Robinia pseudoacacia) is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant f... Tetraploid black locust (Robinia pseudoacacia) is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant forage. However, currently no stock- breeders have adopted it as a major forage in China and other countries for a lack of information on the evaluation of nutritional ingredients of leaves and stems of young tetraploid black locust (YTBL) by in situ digesting tests. The objectives of this study were: 1) to assess the nutritive value of YTBL that bourgeoned from root stumps in the spring by determining the ruminal in situ disappearance kinetics of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) from leaves, stems and a mixture of both leaves and stems (MLS) of YTBL; 2) to compare these kinetic estimates with those of Leymus chinensis, a widely used ruminant forage in China. All samples were evaluated in situ by using five ruminally cannulated crossbred steers (550±22.7 kg BW). The results of 48 hours, the representative incubation period, indicate that in situ disappearance rates of DM and OM in YTBL leaves, stems and MLS are on average about 40% and can attain the level of digestibility of L. chinensis. In situ disappearance rates of leaves, stems and MLS of YTBL for CP and EE were 41% and 58% respectively, rates higher than those of L. chinensis. But the disappearance rates of NDF and ADF were, on average, respectively 30.62% and 24.89% and lower than those ofL. chinensis. By analyzing synthetically all of our results it could be inferred that MLS of YTBL offers effective ruminal degradability of DM, NDF, ADF, CP, EE and OM, similar to the nutrients of L. chinensis. This supports our contention that the YTBL leaves, stems and MLS are suitable feed for those ruminants requiring high levels of nutrients, such as dairy cows and Boer goats, instead of plant forage, which is decidedly lacking in some parts of the world. 展开更多
关键词 tetraploid black locust in situ disappearance kinetics RUMINANT nutritive analyses
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Influencing factors for the disappearance of hemispatial neglect in patients during acute stroke
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作者 Yaobin Long 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期274-276,共3页
BACKGROUND: Some researches are proved that early sitting balance and body motor control performed on patients with stroke and hemiplegia is related to functional prognosis. For patients with hemispatial neglect (HS... BACKGROUND: Some researches are proved that early sitting balance and body motor control performed on patients with stroke and hemiplegia is related to functional prognosis. For patients with hemispatial neglect (HSN) dunng acute stroke, whether HSN disappearance is related to those trainings or not should be further studied. OBJECTIVE: To analyze the correlation between HSN disappearance and related intervention of patients during acute stroke. DESIGN : Case analysis SETTING : Department of Neurology, First Affiliated Hospital of Guangxi Medical University PARTICIPANTS: A total of 21 patients with stroke were selected from the Department of Neurology, the First Affiliated Hospital of Guangxi Medical University from May 2005 to March 2006. Diagnosis criteria: ① Stroke was diagnosed by CT and MRI; ② Diagnosis was coincidence with HSN evaluation criteria; ③ All cases were consent. Exclusion cnteda: Patients who had poly-focus, conscious disturbance, severe amentia and hard communication combined with aphasia were excluded. A total of 12 males and 9 females were included, and the mean age was (68±10) years. Among them, 14 patients had cerebral infarction and 7 had cerebral hemorrhage. METHODS: Disappearance and existence of HSN were analyzed with HSN evaluation criteria: body agnosia, left and nght agnosia, maintenance of supine position, place of things, sitting up straight, center of line measured by eyes, and cutting 30 lines with paring method, Items mentioned below belonged to HSN disappearance: ① without body agnosia; ② without left and nght agnosia; ③ be able to maintain supine position; ④ knowing place of things; ⑤ sitting up straight by one's own; ⑥ be able to measure the center of line by eyes; ⑦ be able to cut 30 lines with paring method. However, only one item belonged to HSN remnant; but only one item belonged to HSN remnant. Numbers of patients who were of body agnosia, left and nght agnosia and difficult maintenance of supine position were observed during acute period (within 1 week) and recovery period (at 2 weeks after onset). Related factors with HSN disappearance contained time of physiotherapy, duration of sitting training (sitting in bed and near bedside: heels fallen to ground, feet loaded heavies, center of gravity located at middle line, head raised towards frontage) and hospitalized time. However, control group was not set up.Measurement data were expressed as Mean+SD and compared with ttest; enumeration data were compared with Chi-square test and Mann-Whitney Utest. P 〈 0.05 was regarded as significant difference. MAIN OUTCOME MEASURES: ① HSN disappearance; ②Numbers of body agnosia, left and right agnosia and difficult maintenance of supine position;③ Correlation among therapeutic time, sitting-training time and hospitalized time. RESULTS: All 21 patients were involved in the final analysis. ① HSN disappearance: Among 21 cases, 2 patients had right HSN disappearance, 19 left HSN disappearance, 8 (38%, 8/21) HSN disappearance, and 13 (62%, 13/21) HSN remnant. Among 8 patients of HSN disappearance, symptoms of 4 cases lasted for 7 days and that of another 4 lasted for 8-12 days. ② Evaluation of HSN disappearance at various phases: Within 1 week, 19% (4/21) HSN patients had body agnosia, left and right agnosia; during recovery period, body agnosia of 20 cases was disappeared and that of 1 case was still survived. Within 1 week, cases with difficult maintenance of supine position were 67% (13/21), but 43% (17/21) during recovery period. ③ Analysis of effective factors on HSN disappearance and related intervention: At acute phase, HSN disappearance through sitting training lasted for (2.5±1.3) days, and remaining HSN symptoms were relieved for (5.0±3.7) days. There was significant difference between them ( x^2= 3.96, P = 0.039). The hospitalized time of patients with HSN disappearance and HSN remnant was (17.6±10.4), (16.2±4.9) days, but there was no significant difference between them (x^2 = 1.41, P = 0.679). Physiotherapy time of patients with HSN disappearance and HSN remnant was (11.1 ±7.5), (11.4±4.1 ) days, but there was no significant difference between them (x^2 = 1.05, P = 0.894). CONCLUSION: Early sitting training may play a possible role in HSN symptom disappearance of patients with stroke. 展开更多
关键词 HSN Influencing factors for the disappearance of hemispatial neglect in patients during acute stroke
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Kinetics of the thermal disappearance of radicals formed during the radiolysis of L-α-anhydrous asparagine
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作者 Ana Neacsu Daniela Gheorghe 《Chemical Reports》 2019年第1期13-21,共9页
An EPR study of paramagnetic centers formed by irradiation of polycrystalline L-α-anhydrous asparagine (L-Asn) was performed. The EPR spectra of gamma irradiated samples at room temperature, shown the presence of thr... An EPR study of paramagnetic centers formed by irradiation of polycrystalline L-α-anhydrous asparagine (L-Asn) was performed. The EPR spectra of gamma irradiated samples at room temperature, shown the presence of three types of paramagnetic centers. A possible mechanisms of formation for the three radical species is suggested, based also on literature data. The kinetics of the disappearance of radicals during thermal annealing indicated a complex mechanism. 展开更多
关键词 L-α-anhydrous ASPARAGINE ionizing radiation paramagnetic centers THERMAL disappearANCE UNPAIRED electron
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Percy's Disappearance
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作者 胡迪 《中学英语园地(高二版)》 2007年第11期19-21,共3页
Percy’s mysterious (神秘的) disappearance upset everybody a great deal. Percy is a performer in a night-club and just before he was due
关键词 Percy NIGHT disappearANCE SNAKE LIKELY SENTENCE at
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The Disappearance of the British Family
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作者 A.J.Dalton 《疯狂英语(阅读版)》 2011年第4期53-53,共1页
The traditional description of the British family is a father, a mother and 2.4 children(on average).However,figures published by the UK government in 2006 revealed that: 66 per cent of marriages in the UK end in divo... The traditional description of the British family is a father, a mother and 2.4 children(on average).However,figures published by the UK government in 2006 revealed that: 66 per cent of marriages in the UK end in divorce,which is the highest rate in 展开更多
关键词 《The disappearANCE of the BRITISH Family》 中学生 英语学习 阅读
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Zhang Heng’s Seismoscope(3):Disappearance & Scientific Value
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作者 Feng Rui Wu Yuxia 《Earthquake Research in China》 2014年第2期130-141,共12页
The ancient idea of Heavenly Punishment confused natural phenomena with social issues,which resulted in Zhang Heng’s tragedy in his later years and seismoscope. The instrument might have been lost in the end of the E... The ancient idea of Heavenly Punishment confused natural phenomena with social issues,which resulted in Zhang Heng’s tragedy in his later years and seismoscope. The instrument might have been lost in the end of the Eastern Han Dynasty. A series of extremely serious chaotic social events caused by war took place,such as a fire in Luoyang,forging coins by destroying copper wares,relocation of the capital,sharp population decrease,and the destruction of the Ling Observatory. Zhang’s scientific thought and successful practice had played an important role in ideological enlightenments at the primary stage of modern seismology at the end of the nineteenth century. There is a glorious course of"innovation—inheritance—re-innovation"of scientific and technical development from the inception Zhang Heng’s seismoscope to the modern seismograph invented by Milne,et al. 展开更多
关键词 候风地动仪 张衡 社会问题 科学思想 自然现象 天文台 地震学 米尔恩
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美他多辛治疗对急性酒精中毒患者苏醒时间症状消失时间和氧化应激反应的影响
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作者 王小银 左爽 +1 位作者 徐礼友 李海山 《河北医学》 2024年第1期163-168,共6页
目的:探究美他多辛治疗对急性酒精中毒患者的影响。方法:选取2020年1月至2022年12月我院急诊收治的104例急性酒精中毒患者为研究对象,采用随机数字表法分为常规组(n=52)和美他多辛组(n=52)。对照组给予常规治疗,观察组常规治疗基础上给... 目的:探究美他多辛治疗对急性酒精中毒患者的影响。方法:选取2020年1月至2022年12月我院急诊收治的104例急性酒精中毒患者为研究对象,采用随机数字表法分为常规组(n=52)和美他多辛组(n=52)。对照组给予常规治疗,观察组常规治疗基础上给予美他多辛治疗。记录两组患者临床指标(苏醒时间、症状消失时间),比较治疗前和治疗后,两组患者血气指标[血氧饱和度(SaO_(2))、氧分压(PO_(2))]及呼气酒精浓度(BrAC)水平,比较治疗前和治疗后,两组患者氧化应激[超氧化物歧化酶(SOD)]状态,治疗前和治疗后,两者患者肝肾功能[丙氨酸氨基转移酶(ALT)、天冬氨酸转氨酶(AST)、血肌酐(Scr)、尿素氮(BUN)]、凝血功能[凝血酶原时间(PT)、凝血酶时间(TT)、活化部分凝血酶时间(APTT)、纤维蛋白原(FIB)]。结果:美他多辛组苏醒时间、症状消失时间均短于常规组(P均<0.05);治疗后,两组患者SaO_(2)、PO_(2)、SOD、FIB水平均较治疗前升高,美他多辛变化水平高于常规组(P均<0.05);BrAC、肝肾功能指标(ALT、AST、Scr、BUN)、部分凝血功能指标(PT、TT、APTT)水平较治疗前降低,美他多辛变化水平高于常规组(P均<0.05)。结论:美他多辛能够缩短急性酒精中毒患者苏醒时间及症状消失时间,改善患者血气状态,缓解患者氧化应激反应,改善患者肝肾功能及凝血功能。 展开更多
关键词 急性酒精中毒 美他多辛 苏醒时间 症状消失时间 氧化应激反应
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Research on the disappearance causes of the Tenghualuo Site in Lianyungang,Jiangsu Province, China 被引量:3
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作者 LI Lan ZHU Cheng +2 位作者 JIANG FengQing ZHAO QuanHong LIN liuGeng 《Chinese Science Bulletin》 SCIE EI CAS 2008年第S1期161-176,共16页
With brilliant civilization during the transitional period from a original clan society to a state society in prehistory,the Neolithic Tenghualuo Site in Lianyungang was discovered by archaeological survey in 1989,whi... With brilliant civilization during the transitional period from a original clan society to a state society in prehistory,the Neolithic Tenghualuo Site in Lianyungang was discovered by archaeological survey in 1989,which was titled as‘one of the nation’s ten great archeological discoveries in 2000’.However,the transgression and the anthropogenic environment deterioration have ever been employed to explain the abandonment of the site.Based on a dynasty framework established by the 14 C dating,and using the experimental methods such as micro-paleontology identification in foraminifera and charophytes, the content test of Rb and Sr,susceptibility analysis as well as granularity and sedimentary facies analysis,some researches on the sediments from the two exploration layers at Tenghualuo Site were conducted,and the following new findings have been gained:Firstly,foraminifera which are relevant to the marine environment were not found in the sediment layer,however,25 charales,which usually live in the freshwater environment,in 07LTT1 exploration samples were found.Among them,3 charales were found in the samples from the forth sediment layer below the late Longshan Cultural layer and 22 charates were from the second sediment layer above the late Longshan Cultural layer.Furthermore,5 plant seeds and 41 fungal spores,together with many carbonation holes,plant seed shells,as well as their roots and stems were also found in the second sediment layer above the late Longshan Cultural layer.Secondly,the cumulative probability curves of the sediments’granularity in both the last and its overlying culture intermittent layers have characteristics of three-phase river sediment curve,and the ratios between Rb and Sr are both quite high in samples from two layers sedimented during the disappearing time of the site.All above-mentioned evidences indicate that disappearance of the Tenghualuo Site was not related to the transgression.The late Longshan Culture of the site could be completely abandoned after a relatively long-term inland water flood. 展开更多
关键词 Tenghualuo SITE FORAMINIFERA CHAROPHYTES GRANULARITY sedimentary FACIES Rb and Sr ratio disappearing reasons
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微光像增强器光晕消失时间测试方法
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作者 吴梦雪 钱芸生 +2 位作者 王璐子 杨淑宁 张琴 《应用光学》 CAS 北大核心 2024年第3期652-658,共7页
光晕(halo)效应对微光像增强器探测的应用造成了不利影响且不可避免。微光像增强器的光晕消失时间缺乏测试方法,因此提出了基于数字目视的光晕消失时间测试系统。该系统通过开关电源给LED光源提供频率为25 Hz、占空比可调的脉冲信号,利... 光晕(halo)效应对微光像增强器探测的应用造成了不利影响且不可避免。微光像增强器的光晕消失时间缺乏测试方法,因此提出了基于数字目视的光晕消失时间测试系统。该系统通过开关电源给LED光源提供频率为25 Hz、占空比可调的脉冲信号,利用高帧率相机连续采集1500张像增强器经直径为3.5 mm小孔后的图像,其中包含若干个完整的明暗周期。通过重复计算标准差,去除偏离平均值的周期序列来优化周期信息,获得亮暗周期内光源熄灭的图片索引,同理可获得光晕消失的图片数量,从而计算得到光晕消失时间。编号为GZ318118A的像增强器光晕消失时间为3.33 ms。测试结果表明,测量装置的重复性为0.863%,可以对光晕消失时间进行有效测试。 展开更多
关键词 光学器件测量 光晕消失时间 微光像增强器 光晕直径
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氯雷他定联合罗红霉素治疗肺炎支原体致上呼吸道感染后咳嗽的疗效
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作者 陈萌 李恒涛 朱海涛 《临床合理用药杂志》 2024年第6期37-39,共3页
目的观察氯雷他定联合罗红霉素治疗肺炎支原体(MP)致上呼吸道感染后咳嗽的疗效。方法选取2020年1月—2022年12月苏州大学医院内科收治的MP致上呼吸道感染后咳嗽患者112例,按照简单信封随机法分为罗红霉素组与联合治疗组,每组56例。罗红... 目的观察氯雷他定联合罗红霉素治疗肺炎支原体(MP)致上呼吸道感染后咳嗽的疗效。方法选取2020年1月—2022年12月苏州大学医院内科收治的MP致上呼吸道感染后咳嗽患者112例,按照简单信封随机法分为罗红霉素组与联合治疗组,每组56例。罗红霉素组患者予以罗红霉素,联合治疗组患者在罗红霉素组基础上联合氯雷他定,2组均连续用药5~7 d。比较2组临床疗效,临床相关指标,不良反应。结果联合治疗组治疗总有效率高于罗红霉素组(94.64%vs.71.43%,χ^(2)=10.712,P=0.001)。联合治疗组体温恢复正常时间、咳嗽缓解时间、咳嗽消失时间、住院时间短于罗红霉素组(P<0.05或P<0.01)。治疗期间,联合治疗组不良反应总发生率低于罗红霉素组(7.14%vs.21.43%,χ^(2)=4.667,P=0.031)。结论MP致上呼吸道感染后咳嗽患者采用氯雷他定联合罗红霉素治疗,可增强抗感染疗效,较快地改善咳嗽症状,且用药安全性较高。 展开更多
关键词 上呼吸道感染 肺炎支原体 咳嗽 氯雷他定 罗红霉素 咳嗽消失时间 治疗结果
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延续性护理措施对小儿支气管肺炎家庭雾化治疗的影响
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作者 周甜 耿静静 +1 位作者 张慧苹 李春景 《妇儿健康导刊》 2024年第6期141-143,共3页
目的探讨延续性护理措施对小儿支气管肺炎家庭雾化治疗的影响。方法选取2022年11月至2023年3月于滨州医学院附属医院就诊的98例支气管肺炎患儿作为研究对象,按照随机数字表法分为参照组(n=49)与研究组(n=49)。两组均实施家庭雾化治疗,... 目的探讨延续性护理措施对小儿支气管肺炎家庭雾化治疗的影响。方法选取2022年11月至2023年3月于滨州医学院附属医院就诊的98例支气管肺炎患儿作为研究对象,按照随机数字表法分为参照组(n=49)与研究组(n=49)。两组均实施家庭雾化治疗,参照组予以常规出院指导干预,研究组予以延续性护理措施。比较两组症状消失时间及家庭雾化治疗总依从率。结果研究组喘憋消失时间、咳嗽消失时间及湿啰音消失时间均短于参照组(P<0.05)。研究组家庭雾化治疗总依从率高于参照组(P<0.05)。结论延续性护理措施应用于小儿支气管肺炎家庭雾化治疗中,可辅助改善临床症状,提高家庭雾化治疗依从性。 展开更多
关键词 延续性护理措施 小儿支气管肺炎 家庭雾化治疗 症状消失时间
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全人照护管理模式在小儿肺炎护理中的应用
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作者 郭少霞 李敏 +1 位作者 卢静仪 游青云 《妇儿健康导刊》 2024年第1期147-149,共3页
目的探讨全人照护管理模式在小儿肺炎护理中的应用效果。方法回顾性分析2020年1月至2022年1月广州医科大学附属第五医院收治的100例肺炎患儿的临床资料,按照不同护理方法进行分组,接受常规护理干预的患儿纳入对照组(50例),接受全人照护... 目的探讨全人照护管理模式在小儿肺炎护理中的应用效果。方法回顾性分析2020年1月至2022年1月广州医科大学附属第五医院收治的100例肺炎患儿的临床资料,按照不同护理方法进行分组,接受常规护理干预的患儿纳入对照组(50例),接受全人照护管理的患儿纳入观察组(50例)。比较两组症状消失时间、住院时间、不良事件总发生率。结果观察组症状消失时间及住院时间均短于对照组(P<0.05);观察组不良事件总发生率低于对照组(P<0.05)。结论全人照护管理模式应用于小儿肺炎护理中能够促进患儿康复,减少不良事件的发生,值得推广应用。 展开更多
关键词 全人照护管理模式 小儿肺炎 症状消失时间
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二维活塞/缸体副微间隙高剪切流场中空泡“消失”现象的实验分析
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作者 李星星 王敬成 +1 位作者 章立超 丁川 《液压与气动》 北大核心 2024年第2期144-152,共9页
在研究二维活塞与缸体配合微间隙中纯剪切空化的过程中,发现该空化现象在外界条件一定的情况下不仅会随着时间发展壮大,也会随着时间的延长萎缩消失。为探究该空化消失现象的可能成因,利用自制的外筒旋转同心圆筒装置在纯剪切流场中构... 在研究二维活塞与缸体配合微间隙中纯剪切空化的过程中,发现该空化现象在外界条件一定的情况下不仅会随着时间发展壮大,也会随着时间的延长萎缩消失。为探究该空化消失现象的可能成因,利用自制的外筒旋转同心圆筒装置在纯剪切流场中构建充分发展的空化气泡分布场,并分别就不同温度、流场压强、油液上方空气占比以及定子外表面结构等因素进行可视化实验研究。实验结果表明:所涉的空化空泡消失现象不同于空化溃灭现象,其开始消失的时间与油液温升和流体压强都具有正相关性,且后者作用更为显著。空泡消失的时间与流场初始压强呈指数下降的关系,压强越高流场的剪切空化现象消失时间越短且温升值越小。 展开更多
关键词 液压元件 二维活塞 微间隙 空化消失 实验研究
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