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Hourly and monthly variations in the surface activity patterns of Hemilepistus reaumurii in arid environments of Tunisia
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作者 Anas AYARI Moez TOUIHRI +1 位作者 Chedlia GHEMARI Karima NASRI-AMMAR 《Journal of Arid Land》 SCIE CSCD 2018年第3期470-481,共12页
Life in desert ecosystems drives animals to adapt their surface locomotor activity according to environmental conditions. In this study, the hourly and monthly variations in the surface activity patterns of the terres... Life in desert ecosystems drives animals to adapt their surface locomotor activity according to environmental conditions. In this study, the hourly and monthly variations in the surface activity patterns of the terrestrial crustacean Hemilepistus reaumurii were investigated. The surface activity of H. reaumurii at the population scale was observed by collecting the hourly active individuals from the sunrise to the sunset of the studied day in each month of 2013 in the Bchachma locality, Tunisia. The collected active individuals were put in perspex boxes(on which we labeled the hourly time interval in which the individuals were collected) in the field and then transported to the laboratory for analysis. Individuals were counted, sexed, and measured in the laboratory. Despite desert conditions in the studied site, H. reaumurii was characterized by a diurnal surface activity, showing a bimodal pattern during the warm months(i.e., May to October). However, it exhibited a unimodal surface activity pattern in the cold months(i.e., February, March, and November). The surface activity was significantly correlated with sunrise and sunset. Moreover, a significant quadratic effect of temperature on the surface activity of H. reaumurii was observed. Furthermore, the study showed that the most important surface activity was recorded in March. The daily exploitation of the temporal niches was significantly different as a function of months. The body size of males was larger than that of females, and the body size of active individuals changed with months. All these behavioural changes in the surface activity represent an adaptive strategy of life in the arid environment. 展开更多
关键词 diurnal activity variation pattern aboveground activity desert isopod temporal niche Hemilepistus reaumurii Tunisia
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Comment on “The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography”
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作者 Salih Uzun Emre Pehlivan Mehmet Gulmez 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第11期1789-1790,共2页
Dear Editor,We have read and reviewed the article entitled"The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography... Dear Editor,We have read and reviewed the article entitled"The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography"by Zhao et al^([1])with great interest. 展开更多
关键词 CT The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography cycle
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LOW FREQUENCY VARIABILITY OF INTERANNUAL CHANGE PATTERNS FOR GLOBAL MEAN TEMPERATURE DURING THE RECENT 100 YEARS
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作者 刘晶淼 丁裕国 余锦华 《Journal of Tropical Meteorology》 SCIE 2002年第1期46-55,共10页
The TEEOF method that expands temporally is used to conduct a diagnostic study of the variation patterns of 1, 3, 6 and 10 years with regard to mean air temperature over the globe and Southern and Northern Hemispheres... The TEEOF method that expands temporally is used to conduct a diagnostic study of the variation patterns of 1, 3, 6 and 10 years with regard to mean air temperature over the globe and Southern and Northern Hemispheres over the course of 100 years. The results show that the first mode of TEEOF takes up more than 50% in the total variance, with each of the first mode in the interannual oscillations generally standing for annually varying patterns which are related with climate and reflecting long-term tendency of change in air temperature. It is particularly true for the first mode on the 10-year scale, which shows an obvious ascending trend concerning the temperature in winter and consistently the primary component of time goes in a way that is very close to the sequence of actual temperature. Apart from the first mode of all time sections of TEEOF for the globe and the two hemispheres and the second mode of the 1-year TEEOF, interannual variation described by other characteristic vectors are showing various patterns, with corresponding primary components having relation with long-term variability of specific interannual quasi-periodic oscillation structures. A 2T test applied to the annual variation pattern shows that the abrupt changes for the Southern Hemisphere and the globe come closer to the result of a uni-element t test for mean temperature than those for the Northern Hemisphere do. It indicates that the 2Ttest, when carried out with patterns of multiple variables, seems more reasonable than the t test with single elements. 展开更多
关键词 global mean temperature patterns of interannual variation abrupt change of climate 2T test
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Between-Tree and Within-Tree Variation in Specific Gravity and Extractive Content in the Wood of Stercufia setigera Del. Grown in Nigeria
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作者 A. O. Oluwadare M. B. Ogunleye 《Journal of Agricultural Science and Technology(B)》 2011年第7期1075-1085,共11页
Variations of wood specific gravity and extractive contents from pith to bark and from base to the top of tree were investigated in a 14-year-old commercial pulpwood species Sterculia setigera Del. Growing in savanna ... Variations of wood specific gravity and extractive contents from pith to bark and from base to the top of tree were investigated in a 14-year-old commercial pulpwood species Sterculia setigera Del. Growing in savanna zone in Nigeria. Tree mean specific gravity averaged 0.37; wood at the base had significant higher specific gravity than those at the top while it increased from pith to bark. For extractive content mean value was 1.20% for wood and 1.72% for bark; i[t varied significantly between trees and from base of the tree to the top and from pith to the bark. Extractive content at the butt and breast height is more than double of the value at the top of the tree. The high extractive content at the base is similar to high specific gravity observed for wood samples from the base. Extractive content of the bast was significantly higher than that of the wood. The low specific gravity show possible suitability of the species for paper making in Nigerian paper mills. The wood of Sterculia setigera showed a significant variation between- and within-trees in the two properties considered, though the wood is light with low extractive content; it is however a potential raw material for large scale pulpwood production in Nigeria. 展开更多
关键词 Specific gravity extractive content patterns of variation Sterculia setigera.
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Study of elemental distribution in soil on the loess plateau of China
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作者 Tian Junliang, Li Yaqi Liu PulingNorthwestern Institute of Soil and Water Conservation, Chinese Academy of Sciences, Shaanxi 712100, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1993年第1期37-44,共8页
Instrument neutron activation analysis (INAA) has been employed in this study to determine 32 elements in soil on the loess plateau. The preliminary results suggest that geochemical characteristics of elements in the ... Instrument neutron activation analysis (INAA) has been employed in this study to determine 32 elements in soil on the loess plateau. The preliminary results suggest that geochemical characteristics of elements in the soil mainly retained those in the parent materials (loess). It has been found that fractional deposition among grain sizes in the process of loess transportation as well as the bioclimate in which the soil developed are main factors affecting the regional variations of elemental distribution in soil on the plateau. Contour maps of element concentrations plotted from the trend analyses exhibit the major patterns of the distributions and variations on the plateau. Furthermore, the study also provides evidence for the aeolian theory of the loess transportation in China. 展开更多
关键词 elements SOIL loess plateau variation patterns.
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NUMERICAL EXPERIMENT ON MID-LATITUDE SST ANOMALY AND VARIATION IN CIRCULATION PATTERN
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作者 葛孝贞 余志豪 葛明 《Acta meteorologica Sinica》 SCIE 1989年第5期594-602,共9页
By means of simulation experiments with a two-dimensional zonal-mean model,a study is made of the influence of the western North-Pacific midlatitude sea-surface temperature(SST)anomalies on the circulation pattern and... By means of simulation experiments with a two-dimensional zonal-mean model,a study is made of the influence of the western North-Pacific midlatitude sea-surface temperature(SST)anomalies on the circulation pattern and wet-seasonal precipitation over the East-China Changjiang-Huaihe reaches and the North-China plain.The SST anomalies are divided into two types,one being“colder in the south and warmer in the north”and the other just opposite,depending on season.Results show that the occurrence of the anomalies is followed by considerable changes in the position of the subtropical high happening for 3-5 months to come.For instance,the spring“colder in the south and warmer in the north”anomalous type (i.e.,colder for 20—35°N,and warmer north of 35°N)leads to the intensification of the summer subtropical high,with the ridge line moved slightly northward,resulting in drought over Changjiang reaches for July-August and in excessive rainfall in the North-China plain,and vice versa. 展开更多
关键词 SST NUMERICAL EXPERIMENT ON MID-LATITUDE SST ANOMALY AND variation IN CIRCULATION pattern MID
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The genome basis and whole-genome patterns of DNA variation of a major oil crop-oil palm Dura
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《Science Foundation in China》 CAS 2017年第1期34-34,共1页
Subject Code:C01The United Nations estimates that world population will increase to 11.2billion in the year 2100.Vegetative oil that serves as one of the major energy resources is essential to feeding human beings.Oil... Subject Code:C01The United Nations estimates that world population will increase to 11.2billion in the year 2100.Vegetative oil that serves as one of the major energy resources is essential to feeding human beings.Oil palm(Elaeis guineensis Jacq,Elaeis from ancient Greek,meaning'oil')produces more than 13times the yield of oil/year/hectare of soybean,one major human annual oil crop.In consequence,it represents a 展开更多
关键词 The genome basis and whole-genome patterns of DNA variation of a major oil crop-oil palm Dura DNA Greek
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Study on Variation Pattern of Microfibril Angle in Chinese Fir
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作者 HUANG Yanhui ZHAO Rongjun FEI Benhua 《Chinese Forestry Science and Technology》 2007年第3期60-65,共6页
Microfibril angle (MFA) in Chinese fir was tested by X-ray diffraction apparatus and calculated by computer software. The results were as follows: MFA was controlled strongly by inheritance, and there was no signif... Microfibril angle (MFA) in Chinese fir was tested by X-ray diffraction apparatus and calculated by computer software. The results were as follows: MFA was controlled strongly by inheritance, and there was no significant difference in MFA among interspecies, juvenile and mature wood. In the longitudinal, MFA reduces with the height rising from 0 to 5.5 m, especially in the heights from 0 to 1.5 m. The values of MFA are nearly consistence from 1.5 to 7.5 m. The variation range was between 10.82°and 12.57°from 1.5 to 7.5 m, R2 of power equation achieved 0.932 1, and analysis of variance indicated that the variation of MFA was not significant from 1.5 to 7.5 m, The age of the trees had an important influence on MFA, consequently, the difference in MFA was significant among annual rings in radial, which was maximal in near pith and reduced rapidly from the pith to sapwood, and its decline tendency was slow beyond the ninth annual ring. MFA reached minimum value at the 15th annual ring, and the difference reached more than 20° and R^2 of binomial equation achieved 0.755 6. 展开更多
关键词 Chinese fir (Cunninghamia Ianceolata) microfibril angle X-ray diffraction variation pattern
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