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Interrelations among acarine, fungal, and environmental components of bulk grain ecosystems were determined by canonical correlation analyses. Twenty-seven variables were measured monthly in samples collected from 2 identical grain bulks in a granary in Winnipeg during the years 1959–67. The relationships between 9 kinds of arthropods and 6 environ mental variables, and between the same arthropods and 12 kinds of actinomycetes and fungi were examined. The maximum canonical correlation between arthropods and environmental factors was 0.35, and between arthropods and microorganisms was 0.28; both are highly significant (p<0.001). In the first analysis correlations of the variables with the canonical variates revealed that correlations of the variables with the canonical variates revealed that sampling location, depth, and temperature are the primary environmental antecedents involved, and the criterion is primarily composed of mites Tarsonemus spp.,Tydeus interruptus and the psocid, Lepinotus reticulatus. In the second analysis the fungi Nigrospora sphaerica, Aspergillus spp., and Cochliobolus sativus are involved with the mites Cheyletus eruditus and Acarus siro. Generally, the results of these analyses complement the findings of factor and regression analyses of the same data reported earlier. 相似文献
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本文描述一个新的外在分类方法—典范指示种分析。它是以典范对应分析排序轴为基础,同时使用植被数据和环境数据,其结果能更好地反映植被与环境的关系。我们用该方法对英国威尔士北部山地草甸的数据进行了分析,结果证明它是较理想的分析方法。 相似文献
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应用排序分析藓类植物分类群分布与气候因素的关系 总被引:13,自引:1,他引:13
以我国21个山地藓类植物区系和气象资料为基础,应用典范对应分析(CCA)和除趋势典范对应分析(DCCA),比较了21个山地中藓类植物61个科,曲尾藓科(Dicranaceae)23个属、曲柄藓属(Campylopus)17种及曲尾藓属(Dicranum)35种分布与年均温度、>10℃积温、1月均温、7月均温、年均相对湿度、年均降雨量、年有雾天数、年有霜天数和年日照时数的关系,通过排序进行了直观的展示;同时还应用典范对应分析直观地反映了包括长白山在内的我国9个山地苔藓植物地理成分组成上的相似性及它们与气候因素间的关系.本文研究表明将DCCA和CCA应用到植物区系地理学研究上是可行的. 相似文献
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C L Lavelle 《American journal of physical anthropology》1977,46(3):415-421
Sixteen dimensions were measured from the maxillary and mandibular dental arches of different ethnic groups of man, apes and monkeys. Multivariate analysis showed that discrimination was possible among the ethnic groups of man on the one hand and between the ape and monkey samples on the other. Nevertheless, the actual degree of discrimination between the primate samples depended upon whether the maxillary or mandibular arch dimensions were analysed. Furthermore, subsequent inclusion of the dental arch dimensions of fossil hominoid samples into the analysis confirmed the taxonomic significance of the dental arch, although its importance must await the acquisition of the more non-human primate data. 相似文献
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Christopher L. B. Lavelle 《American journal of physical anthropology》1984,63(4):397-403
In a study of maxillary right first premolar morphology, multivariate analysis showed varying degree of separation between four human ethnic groups depending upon the actual metrical profile included in the analysis. Such ethnic discriminations were not possible from visual inspection or univariate analysis of individual crown diameters. Although the interpretation of such ethnic contrasts remains obscure, this study demonstrated the potential of multivariate statistical techniques in the investigation of odontometric data. 相似文献
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Lecarpentier Y Blanc FX Quillard J Hébert JL Krokidis X Coirault C 《Journal of theoretical biology》2005,235(3):381-392
Statistical mechanics provides the link between microscopic properties of matter and its bulk properties. The grand canonical ensemble formalism was applied to contracting rat skeletal muscles, the soleus (SOL, n = 30) and the extensor digitalis longus (EDL, n = 30). Huxley's equations were used to calculate force (pi) per single crossbridge (CB), probabilities of six steps of the CB cycle, and peak muscle efficiency (Eff(max)). SOL and EDL were shown to be in near-equilibrium (CB cycle affinity 2.5 kJ/mol) and stationary state (linearity between CB cycle affinity and myosin ATPase rate). The molecular partition function (z) was higher in EDL (1.126+/-0.005) than in SOL (1.050+/-0.003). Both pi and Eff(max) were lower in EDL (8.3+/-0.1 pN and 38.1+/-0.2%, respectively) than in SOL (9.2+/-0.1 pN and 42.3+/-0.2%, respectively). The most populated step of the CB cycle was the last detached state (D3) (probability P(D3): 0.890+/-0.004 in EDL and 0.953+/-0.002 in SOL). In each muscle group, both pi and Eff(max) linearly decreased with z and statistical entropy and increased with P(D3). We concluded that statistical mechanics and Huxley's formalism provided a powerful combination for establishing an analytical link between chemomechanical properties of CBs, molecular partition function and statistical entropy. 相似文献
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《Journal of structural biology》2014,185(2):223-227
A number of light and heavy chain canonical residue core redesigns were made in a therapeutic antibody (AQC2, anti-VLA1) Fab to explore the consequences to binding affinity and stability. These positions are all loop supporting, primarily CDR1 residues which do not directly contact the antigen. Structure based methods were used with and without consensus sequence information. 30 constructs were made, 24 expressed, and 70% of the designs using consensus sequence information retained binding affinity. Some success maintaining stability with more extreme redesigns suggests a surprising tolerance to mutation, though it often comes at the cost of loss of binding affinity and presumed loop conformation changes. In concordance with the expected need to present an ordered surface for binding, a relationship between decreased affinity and decreased stability was observed. Overpacking the core tends to destabilize the molecule and should be avoided. 相似文献
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应用典范对应分析探讨长白山金发藓科植物的生态位分化 总被引:7,自引:1,他引:7
应用典范对应分析(Canonical Co rrespondence Analysis, CCA)对长白山主要生态系统30个样点中的13种金发藓科植物分布与环境因子间的关系进行了研究。发现在长白山地区,金发藓科植物在海拔高度、土壤含砂量、含水量、酸度、光照条件等资源维上存在明显的生态分化现象。13种金发藓科植物中,球蒴金发藓(Polytrichum sphaerothecium(Besch.)C.Mull.、高山异发藓短叶变种(Polytrichastrum alpinum var. brevifolium(R.Br.)Brid.)在海拔上,拟异发藓(Polytrichastrum formosum(Hedw.)G.L.Smith)、变形异发藓(Polytrichastrum dicipensLimpr.)、毛尖金发藓(Polytrichum piliferum Schred.ex Hedw.)、桧叶金发藓(Polytrichum juniperinum Willd.ex Hedw.)在光照上以及大金发藓(Polytrichum commune Hedw.)、直叶金发藓(Polytrichum juniperinum ssp. strictum(Brid.)Nhy.&Sael.)在土壤酸度与水分上的生态要求比较接近。 相似文献
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C L Lavelle 《American journal of physical anthropology》1974,41(1):63-69
Thirty-two dimensions of the maxillary and mandibular dental arches were measured on 320 adult skulls derived from Anglo-saxon to modern times. Multivariate analysis showed varying patterns of contrast between the samples, depending upon which arch dimensions were considered. The results suggest that dental arch changes occur independently of jaw changes. 相似文献
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K. Steudel 《American journal of physical anthropology》1981,55(3):399-410
This study aims to clarify the relationship of primate bony pelvic structure to locomotor habit. As with most of the postcranial skeleton, the pelvic bones of species within the Ceboidea and the Cercopithecoidea are remarkably similar visually except for variations in size. Yet there are substantial differences in locomotor pattern between the species in these taxa. I performed canonical analyses on a sample of 17 pelvic variables describing 22 primate species of the Ceboidea, the Cercopithecoidea, and the Hominoidea to discover which variables were significant in separating them into groups. In both analyses there was good separation of major taxa and additional separation of groups that differed in locomotor habit. The separation of colobine from cercopithecine monkeys was particularly consistent. In the analysis, including all 22 species, the variables given particular weight by the canonical analysis were the same as those traditionally used by anatomists for the same purpose. Specifically, breadth of the ischial tuberosity (reflecting presence or absence of ischial callosities) separated the Old from the New World monkeys. Breadth of the iliac tuberosity, in which man and to some extent other hominoids differ from other primates, and ilium height, in which man differs from other primates, were significant. Sagittal diameter of the pelvis was also substantially weighted. Having established that the technique would select variables of anatomical significance, the same method was applied to a study of monkeys only where the characteristics that differ between groups are not well established. Breadth of the ischial tuberosity was again important in separating the Ceboidea from the Cercopithecoidea. Discrimination of locomotor groups within these large divisions was brought about mainly by ischial length and the sagittal diameter of the pelvis. In studying these variables and their relationship to size in greater detail, it was found that among cercopithecoid monkeys, the colobines showed relatively lower values than did cercopithecines for both these dimensions. Atelines showed low values for ischial length but high values for the sagittal pelvic diameter. Biomechanical explanations of these observations are suggested. 相似文献
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Isidora Katara Janine Illian Graham J. Pierce Beth Scott Jianjun Wang 《Hydrobiologia》2008,612(1):33-48
Recent research suggests the coupling of climatic fluctuations and changes in biological indices that describe species richness,
abundance and spatiotemporal distribution. In this study, large-scale modes of atmospheric variability over the northern hemisphere
are associated with chlorophyll-a concentration in the Mediterranean. Sea level atmospheric pressure, air temperature, wind
speed and precipitation are used to account for climatic and local weather effects, whereas sea surface temperature, sea surface
height and salinity are employed to describe oceanic variation. Canonical Correlation Analysis was applied to relate chlorophyll
concentration to the above-mentioned environmental variables, while correlation maps were also built to distinguish between
localized and distant effects. Spectral analysis was used to identify common temporal cycles between chlorophyll concentration
and each environmental variable. These cycles could be interpreted as mechanistic links between chlorophyll and large-scale
atmospheric variability. Known teleconnection patterns such as the East Atlantic/Western Russian pattern, the North Atlantic
Oscillation, the Polar/Eurasian pattern, the East Pacific/North Pacific, the East Atlantic jet and the Mediterranean Oscillation
are found to be the most important modes of atmospheric variability related to chlorophyll-a concentration and distribution.
The areas that are mostly affected are near the coasts and areas of upwelling and gyre formation. The results also suggest
that this influence may arise either through local effects of teleconnection patterns on oceanic features or large-scale changes
superimposed onto the general circulation in the Mediterranean.
Guest editor: V. D. Valavanis
Essential Fish Habitat Mapping in the Mediterranean 相似文献
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The Grand Canonical Monte Carlo method was used to analyse the phenomenon of adsorption of aromatic compounds (i.e. phenol,
toluene, benzoic acid and salicylic acid) on the surface of the titania-silica (TiO2/SiO2) catalyst. We found that different types of interactions play important roles in the adsorption of molecules having polar
and non-polar groups. Moreover, we found that the interactions between sorbate molecules are strong, and are the cause of
multilayer adsorption occurring in the investigated temperature and pressure range.
Presented at: Modeling and Design of Molecular Materials, 10–15 September 2006, Wrocław, Poland. 相似文献
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Designing cysteine proteinase inhibitors as antitrichomonal drugs requires knowledge of which cysteine proteinases are essential to the parasite. In an attempt to obtain such information, the effects of a number of cysteine proteinase inhibitors on trichomonad growth in vitro and proteinase activity were investigated. The broad specificity inhibitor trans-epoxysuccinyl-l-leucylamido-(4-guanidino)butane (known as E-64) had little effect on growth of Trichomonas vaginalis (27% inhibition at 280 μM, none at 28 μM) even though the addition of 2.8 μM E-64 to growth medium resulted in inhibition of all but two (apparent molecular masses: 35 k and 49 k) of the parasite's proteinases detected by gelatin SDS-PAGE. This shows that many of the parasite's cysteine proteinases are not essential for growth in axenic culture. In contrast, a peptidyl acyloxymethyl ketone, N-benzoyloxycarbonyl-Phe-Ala-CH2OCO-(2,6,-(CF3)2)Ph, at 16 μM killed T. vaginalis and severely inhibited growth of Tritrichomonas foetus. Exposure of Trichomonas vaginalis to 16 μM of this compound for 1 h resulted in both the 35 kDa and 49 kDa proteinases being inhibited, whereas some other proteinases were unaffected. Similar distinctions between the inhibitor sensitivity of the parasite's cysteine proteinases were apparent when a biotinylated peptidyl diazomethyl ketone was used to detect active proteinases. These data suggest that the growth inhibitory effects of the peptidyl acyloxymethyl ketone are through inhibition of cysteine proteinases that are not affected when the parasites are grown in the presence of E-64. At least one of these enzymes, which include the 35 kDa and 49 kDa cysteine proteinases, must be essential and so a suitable target for chemotherapeutic attack. 相似文献
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J. I. Weller G. R. Wiggans P. M. VanRaden M. Ron 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(8):998-1002
Effects of individual quantitative trait loci (QTLs) can be isolated with the aid of linked genetic markers. Most studies have analyzed each marker or pair of linked markers separately for each trait included in the analysis. Thus, the number of contrasts tested can be quite large. The experimentwise type-I error can be readily derived from the nominal type-I error if all contrasts are statistically independent, but different traits are generally correlated. A new set of uncorrelated traits can be derived by application of a canonical transformation. The total number of effective traits will generally be less than the original set. An example is presented for DNA microsatellite D21S4, which is used as a marker for milk production traits of Israeli dairy cattle. This locus had significant effects on milk and protein production but not on fat. It had a significant effect on only one of the canonical variables that was highly correlated with both milk and protein, and this variable explained 82% of the total variance. Thus, it can be concluded that a single QTL is affecting both traits. The effects on the original traits could be derived by a reverse transformation of the effects on the canonical variable. 相似文献