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1.
In 1972(74)–1996(98), repeated phytocoenological surveys of natural mixed forest remainders were made on permanent plots in
the Šumava Mts. in the south-western part of the Czech Republic. The surveys were made in localities with subsoils poor in
nutrients (Boubín-Milešice—27 plots) and in a locality with nutrient-rich subsoil (Stožec—15 plots). Vegetation dynamics were
studied according to the year of measurement and the nutrient capacity of the geological bedrock. We used the indices of floristic
similarity, the calculation of plant communities’ characteristics (Shannon–Wiener’s index, equitability index), the calculation
of taxa characteristics (fidelity, average cover, constancy) and multivariate ordination analyses—indirect (DCA) and direct
(CCA). Changes in environmental conditions were studied between the years of measurement and between the localities using
bioindication—by the calculation of Ellenberg indicator values (EIV) for plant communities. Over 24 years both the nutrient-poor
site and the nutrient-rich site showed a considerable reduction in the tree layer cover and conversely the advancement of
shrub layers. The coverage degree of dominants in the main tree layer (Fagus sylvatica, Picea abies and Abies alba) markedly decreased. Abies alba also exhibited a pronounced drop in constancy. On the other hand, the lower tree layer and shrub layers in Boubín-Milešice
exhibited a distinctive invasion of Fagus sylvatica. An increase in the frequency of Sorbus aucuparia and a decrease in the frequency of Ulmus glabra were determined too. Herb layer changes were highly significant between the 1970s and the 1990s with qualitative changes
being greater than quantitative changes. The number of species and Shannon–Wiener’s index increased. A significant difference
was recorded between the nutrient-poor and the nutrient-rich sites in the values of the quantitative similarity of relevés
with other differences being insignificant. The nutrient-poor sites exhibited herb layer homogenisation. A significant increase
of EIV for light was found on both site types. The changes in phytocoenoses were interpreted partly as developmental trends
(caused by indirect impact of man—e.g. fluctuations in game populations since the 18th century, the impact of air pollution);
partly as cyclical changes connected with the developmental cycle of the natural temperate forest. 相似文献
2.
3.
Yuzuru Hamada Tsuyoshi Watanabe Osamu Takenaka Bambang Suryobroto Yoshi Kawamoto 《Primates; journal of primatology》1988,29(1):65-80
The body color of Sulawesi macaques was measured quantitatively and compared among the different monkeys. As a result, divergence
models for extant Sulawesi macaques, withtonkeana as the starting point and fading as the sole direction of color change, were inferred as follows: (1) fading slightly on
the upper half of the body—nigra, fading more on the proximal part of the body—nigrescens; (2) fading over the whole body—maura; (3) fading greatly on the legs—hecki; and (4) fading on the distal part of the body—ochreata, fading more over the whole body, including the proximal part of the body—brunnescens. The color changed progressively in the order of (1) through (4). The divergence model, excluding the position ofhecki (3), supports the speciation model ofFooden (1969). If the proto-Sulawesi macaques had a body color pattern similar to the livingnemestrina, darkening would have been necessary for the evolution of the Sulawesi macaques after their immigration, and it may have
been acquired as an adaptation to the ground (forest floor) living nature of the Sulawesi macaques, together with influences
deriving from the insularity and/or from the absence of predators. 相似文献
4.
Walter W. Ferguson 《Primates; journal of primatology》1989,30(4):561-569
Leonard andHegmon (1987) compare a series of dental metrics of ‘Australopithecus afarensis
Johanson, White, andCoppens, 1978’ with criteria for modern apes, to test the hypothesis that ‘A. afarensis’ represents a single species. They also compare the morphology of the lower third premolar. The dental breadth of ‘A. afarensis’ shows a wide range of variation, particularly in the lower third premolar morphology which displays greater variation than
in modern apes—yet the study concludes that the single species hypothesis cannot be rejected.
The study is flawed by applying criteria for pongids inappropriate for a hominid. When ‘A. afarensis’ is compared with criteria for hominids, the range of variation in dental size, breadth, and third premolar morphology is
greater than that in any hominid species. The single species hypothesis is, therefore, once again rejected. Moreover, the
name ‘A. afarensis’ is preoccupied byPraeanthropus africanus (Weinert) and must be dropped. 相似文献
5.
Gilligan’s (1982) refinement of Kohlberg’s theory on moral development operates on two theses: (1) females, more so than males,
reach moral decisions based on the personalities of the relevant individuals; and (2) female behaviors stemming from moral
decisions are based upon “care” and “responsibility for others.” This article accepts the first thesis but argues that the
second is incorrect. That is, self-interest—i.e., aiding “blood” kin and/or carefully monitoring reciprocity—rather than “altruism”
is argued to be the operant dynamic in forging distaff morality and resultant behavior. Six empirical examples are presented
as contraindicative of Gilligan’s second thesis. Finally, it is suggested that selection for the psychological traits of independence
and the mastery of subtle social chess yielded ancestral females who had more descendants—us—than did females with alternative
profiles.
Nancy S. Coney is a professor at Western Illinois University and is interested in both clinical and nonclinical aspects of
women’s psychology.
Wade C. Mackey is interested in biocultural anthropology and has authored two books on fathering:Fathering Behaviors (Plenum, 1995) andThe American Father (Plenum, 1996). 相似文献
6.
Carlos A. Peres 《International journal of primatology》1994,15(3):333-372
I studied gray woolly monkeys (Lagothrix lagotricha cana)in an undisturbed central Amazonian terra firme forest, near the headwaters of the Urucu river, Tefé, Amazonas, Brazil (5°50’S,
65°16’W). I report the diet and feeding ecology of a group of 39–41 individuals, based on systematic feeding observations
obtained during 11 months. Woolly monkeys are primarily frugivorous; mature fruits and young seeds account for 83 and 7% of
3298 feeding records, respectively. On a seasonal basis, however, they relied heavily on young foliage (16%), seed-pod exudates
(6%), and flowers (3%), particularly during the greatest annual period of ripe fruit scarcity, as determined by a phenological
survey. Animals represent only 0.1% of their year-round diet, and they spent little time capturing arthropods and other prey
items. Although at least 225 plant species, belonging to 116 genera and 48 families, are in their diet, the three top-ranking
families (Moraceae, Sapotaceae, and Leguminosae) account for 43% of their food species and 63% of the time they spent feeding
on a year-round basis. I compare the feeding ecology and diet of L. 1. canain the Urucu and other taxa of Lagothrixin upper Amazonia — the last large-bodied Neotropical primates to be studied — to those of other ateline genera: Atelesand Brachyteles.
An erratum to this article is available at . 相似文献
7.
Biological activity of secondary metabolites produced by a plant-growth-promotingPseudomonas fluorescens was evaluated. The strain produced antibiotics phenazine (PHE), 2,4-diacetylphloroglucinol (PHL) and siderophore pyoverdin
(PYO) in standard King’s B and succinic acid media, respectively. After extraction, PYO was identified by comparing the UV-spectra
and moss-green color development after ‘diazotized sulfanilic acid’ (DSA) spray in TLC. PHE and PHL were identified by comparing
standard compounds on TLC and orange-color development immediately after DSA spray.In vitro antibiosis study of the metabolites revealed their antibacterial and antifungal activity against bacterial test organismsCorynebacterium sp.,Mycobacterium phlei andM. smegmatis and test fungiFusarium moniliforme, F. oxysporum, F. semitectum, F. solani andRhizoctonia solani. A statistically significantly higher plant growth was recorded in siderophore-amended plantlets under gnotobiotic conditions
whereas PHE and PHL did not show any plant-growth-promoting activity. These results support the importance of the secondary
metabolites produced by the strainP. fluorescens in enhancing plant growth and in controling fungal and bacterial pathogens. 相似文献
8.
Paula M. Leddy Timothy D. Paine Thomas S. Bellows Jr. 《Entomologia Experimentalis et Applicata》1993,68(1):43-50
The relationship between ovipositional preference ofSiphoninus phillyreae (Haliday) (Homoptera: Aleyrodidae) and host plant suitability on seven host plant species (Citrus sinensis (L.) cv. ‘Washington’ [navel orange],Fraxinus uhdei (Wenz.) [shamel ash],Heteromeles arbutifolia Roemer [toyon],Malus domestica Mill. cv. ‘Granny Smith’, [apple],Pistacia vera L. cv. ‘Kerman’ [pistachio],Prunus persica (L.) cv. ‘O’Henry’ [peach], andPyrus communis L. cv. ‘Bartlett’ [pear]) was evaluated. Ovipositional preference ofS. phillyreae was determined by measuring egg density after adult female whitefies were given a simultaneous choice of all host plants
for oviposition. Immature survival, developmental time, and adult size were examined to determine host plant suitability forS. phillyreae. All studies were performed under greenhouse conditions.S. phillyreae showed distinct ovipositional preference among host plant species. Host plant species had a significant effect on immature
survival, but little or no effect on developmental time or forewing length. For four of the seven host plant species tested,
there was an association between ovipositional preference and survival. 相似文献
9.
The main idea of S-curve diagram is to assign different angle values (from 0° to 180°) to different nucleotide acid residues
or to different protein amino acids, and then according to cos α
j
and sin α
j
, the values are accumulated to construct an S-curve diagram, which is in strict one-to-one correspondence with the biological
sequence. In addition, the S-curve diagram proves to be without the degeneracy phenomenon, so that both the degeneracy problem
represented by diagrams and the problem of visualization for biological sequence data are solved. Meanwhile, a new approach
to differentiate the similarity of biological sequences—the degree of similarity—is put forward on the basis of the S-curve
diagram. To put it in detail, the least square approach is first adopted to obtain a straight line equation according to the
S-curve diagram, then according to the distance formula of the point to the straight line, the average ratio of square sum
for the distance between the S-curve and the straight line is calculated, and finally, the similarity of the biological sequences
is presented by the new standard—the degree of similarity. As is shown by the experimental results, the S-curve diagram can
better represent biological sequences (such as protein’s) within Cartesian coordinate system, and the mutation point of biological
sequence. Thus, it turns out that the new standard—the degree of similarity is of obviously great advantage. 相似文献
10.
We have created a DNA construct, TREGED (transposon-and recombinase-mediated genome deletion), that will automatically induce
deletions in plant genomes. TREGED contains the maizeAc/Ds transposon, the yeast R-RS site-specific recombination system, the bacterialtetR repression systems, a novel artificial superintron, and the marker genesGUS andLc. The novelty of TREGED is that only one cross is required to trigger a sequence of events leading to deletion and, simultaneously,
to a color assay to detect the deletion. Crossing is done to introduceAc transposase which activatesDs transposition from TREGED to a nearby chromosome region.Ds transposition, in turn, activates recombination between an engineeredRS site on TREGED and anRS site on the transposedDs fragment, thus deleting the genome segment between TREGED andDs. The recombination event also deletesLc orGUS and part oftetR, which triggers expression ofGUS orLc color genes for an upstream or downstream deletion respectively. Each TREGED insertion site will produce multiple kinds of
deletions identifiable by inspecting a single F1 plant and its progeny for colored tissue. The color markers can also be used to differentiate between deletion and other
more rare events such as translocation and inversion. We anticipate TREGED will greatly simplify the steps required to obtain
useful deletions—eventually allowing the creation of detailed deletion libraries. Such libraries will be particularly useful
for anlaysis of gene and chromatin function in plant species with large genomes. 相似文献
11.
The antimicrobial activity of the protoberberine, alkaloid, berberine, isolated fromMahonia aquifolium, was evaluated against 17 microorganisms including two Gram-negative bacteria—Pseudomonas aeruginosa andEscherichia coli (both resistant and sensitive), two Gram-positive bacteria—Bacillus subtilis andStaphylococcus aureus, Zoogloea ramigera, six filamentous fungi—Penicilium chrysogenum, Aspergillus niger, Aureobasidium pullulans (black and white strain),Trichoderma viride (original green strain and brown mutant),Fusarium nivale, Mycrosporum gypseum, and two yeasts—Candida, albicans andSaccharomyces cerevisiae. The IC50, minimum inhibitory concentration (MIC), minimum microbicidal concentration (MMC) and minimum microbistatic concentration
(MMS) varied considerably depending on the microorganism tested, the sensitivity decreasing as follows:S. aureus >P. aeruginosa S (sensitive) >E. coli S>P. aeruginosa R (resistant) >E. coli R>B. subtilis>Z. ramigera>C. albicans>S. cerevisiae>A. pullulans B (black)>A. pullulans W (white)>T. viride Br (brown)>M. gypseum>A niger>F. nivale>P. chrysogenum>T. viride G (green). 相似文献
12.
M. A. Kovalyova L. I. Kovalyov I. Yu. Toropygin S. V. Shigeev A. V. Ivanov S. S. Shishkin 《Biochemistry. Biokhimii?a》2009,74(11):1239-1252
Proteins from bioptates and autoptates of human skeletal muscle m. vastus lateralis were separated by O’Farrell two-dimensional gel electrophoresis (2DE). MALDI-TOF MS and MS/MS enabled identification of 89
protein spots as expression products of 55 genes. A modification of the O’Farrell’s method including non-equilibrium electrophoresis
in a pH gradient allowed detection — among major sarcomeric, mitochondrial, and cytosolic proteins — of several proteins,
such as PDZ- and LIM domain-containing ones (pI > 8.70), fragments of known proteins, and a stable complex of heavy and light ferritin chains. The data underlie further
studies of human skeletal muscle proteins in terms of molecular mechanisms of some physiological and pathological processes. 相似文献
13.
Endo-β-N-acetylglucosaminidases (ENGases) cleave N-glycans from proteins and/or peptides by hydrolyzing the O-glycosidic linkage between
the two core-N-acetylglucosamine (GlcNAc) residues. Although, two homologous genes potentially encoding ENGases have been identified in
Arabidopsis thaliana, their respective substrate specificity, their subcellular and their organ specific localization was hitherto unknown. In
order to investigate the role of ENGases in this model plant species, we transiently expressed the two A. thaliana genes in Nicotiana benthamiana and determined the substrate specificities, as well as the Km values, of the purified recombinant enzymes. The assumed predominantly
cytosolic localisation of both enzymes, here referred to as AtENGase85A and AtENGase85B, was determined by confocal microscopy
of plant leaves expressing the respective GFP-fusion constructs. For the individual characterization of the two enzymes expression
patterns in planta, single knock-out plants were selected for both genes. Although both enzymes are present in most organs, only AtENGase85A
(At5g05460) was expressed in stems and no ENGase activity was detected in siliques. A double knock-out was generated by crossing
but—like single knock-out plants—no apparent phenotype was observed. In contrast, in this double knock-out, free N-glycans
carrying a single GlcNAc at the reducing end are completely absent and their counterparts with two GlcNAc—visible only at
a trace level in wild type—accumulated dramatically. 相似文献
14.
The role of the Orii’s flying-fox (Pteropus dasymallus inopinatus) as a pollinator and a seed disperser on Okinawa-jima Island was investigated by direct observations and radio-tracking from
October 2001 until January 2006. We found that Orii’s flying-fox potentially pollinated seven native plant species. Its feeding
behavior and plant morphological traits suggested that this species is an important pollinator of Schima wallichii liukiuensis and Mucuna macrocarpa. The flying-fox also dispersed the seeds of 20 native plant species. The seeds of all plants eaten by the flying-fox were
usually dropped beneath the parent tree, although large fruits of four plant species were occasionally brought to the feeding
roosts in the mouth, with the maximum dispersal distance—for Terminalia catappa—estimated to be 126 m. Small seeds of 11 species (mostly Ficus species) were dispersed around other trees, during the subsequent feeding session, through the digestive tracts, with the
mean dispersal distance for ingested seeds estimated at 150 ± 230.3 m (±SD); the maximum dispersal distance was 1833 m. A
comparison of the seed dispersal of available fruits according to the size of flying-foxes and other frugivores suggested
that the seed dispersal of eight plant species producing large fruits mostly depended on Orii’s flying-fox. On Okinawa-jima
Island, the Orii’s flying-fox plays an important role as a pollinator of two native plants and as a long-distance seed disperser
of Ficus species, and it functions as a limited agent of seed dispersal for plants producing large fruits on Okinawa-jima Island. 相似文献
15.
M.J. Iqbal O.U.K. Reddy K.M. El-Zik A.E. Pepper 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(4):547-554
Reliable information about the evolutionary and genetic relationships of various germplasm resources is essential to the establishment
of rational strategies for crop improvement. We used AFLPs to study the genetic relationships of 43 cultivars of Gossypium hirsutum representative of the genomic composition of modern ’Upland’ cotton. The study also included representatives of the related
tetraploid species Gossypium barbadense, as well as the diploid species Gossypium raimondii, Gossypium incanum, Gossypium herbaceum and Gossypium arboreum. We tested 20 primer combinations that resulted in a total of 3,178 fragments. At the species level, and above, genetic similarities
based on AFLPs were in agreement with the known taxonomic relationships. Similarity indices ranged from 0.25 to 0.99. Representatives
of the G. hirsutum germplasm resources utilized in North America, including secondary accessions collected by breeders in Central America (’Acala’,
’Tuxtla’, ’Kekchi’) and the southwestern US (’Hopi Moencopi’), formed a single cluster with exceedingly limited genetic diversity
(with many pairwise similarity indices >0.96) We concluded that these accessions were derived from the same genetic pool.
The early maturing or ’latifolium’ or ’Mexican Highlands’ cultigens from which these cultivars were derived appear to have
had extremely limited genetic diversity, perhaps as a result of a severe genetic bottleneck resulting from the selection pressures
of domestication. Outside of the major G. hirsutum cluster, well-supported phylogenies were inferred. Inside this cluster, phylogenies were obscured by limited diversity, reticulation
and lineage sorting. The implications of these findings for cotton improvement are discussed.
Received: 23 May 2000 / Accepted: 23 January 2001 相似文献
16.
Growth response of two grasses and a legume on coal fly ash amended strip mine spoils 总被引:5,自引:0,他引:5
Joseph L. Fail Jr. 《Plant and Soil》1987,101(1):149-150
The use of fly ash as an amendment for strip mine soils was studied under field conditions. Three plant species—Agrostis tenuis var. Highlander,Festuca arundinacea, andLespedeza cuneata—were grown in strip mine plots. Half of the plots were treated with an equivalent of 70 metric tons per hectare of coal fly
ash and half were untreated. Biomass production ranged from 5 to 30 times higher in fly ash treated plots compared to untreated
plots. No toxic effects to the plants were observed. 相似文献
17.
The compositions of leaf monoterpenoids from 11 species in the Juniperus section (Juniperus chinensis var. chinensis,J. virginiana, J. communis var. montana,J. rigida, J. chinensis var. globosa,J. chinensis var. sargentii,J. chinensis ‘Kaizuka Variegata’,J. squamata ‘Wilsonii’,J. x media ‘Shimpake’,J. x media ‘Plamosa Aurea’, andJ. squamata ‘Aloderi’) were comparatively analyzed by GC-MS. Of the 24 compounds identified, α-pinene, myrcene, limonene, terpinolene,
and bornyl acetate were common to all, but particular combinations differed remarkably among taxa. The simplest composition
(eight compounds) was found in.J, chinensis var. chinensis; the most complex (19 compounds), inJ. x media ‘Shimpake’. Cluster analysis generated four distinctive clades within the Juniperus section. The minimum spanning network
revealed thatJ. squamata ‘Wilsonii’ andJ. x media ‘Shimpake’ were most similar in their chemical makeup. 相似文献
18.
Kurdrid P Sirijuntarut M Subudhi S Cheevadhanarak S Hongsthong A 《Molecular biotechnology》2008,38(3):203-209
The results of our previous study on heterologous expression in Escherichia coli of the gene desD, which encodes Spirulina Δ6 desaturase, showed that co-expression with an immediate electron donor—either cytochrome b
5
or ferredoxin—was required for the production of GLA (γ-linolenic acid), the product of the reaction catalyzed by Δ6 desaturase. Since a system for stable transformation of Spirulina is not available, studies concerning Spirulina-enzyme characterization have been carried out in heterologous hosts. In this present study, the focus is on the role of the
enzyme’s N- and C-termini, which are possibly located in the cytoplasmic phase. Truncated enzymes were expressed in E. coli by employing the pTrcHisA expression system. The truncation of the N- and C-terminus by 10 (N10 and C10) and 30 (N30 and
C30) amino acids, respectively, altered the enzyme’s regioselective mode from one that measures from a preexisting double
bond to that measuring from the methyl end of the substrate. 相似文献
19.
Higher plant plastid DNA (ptDNA) is generally described as a double-stranded circular molecule of the size of the monomer of the plastid genome. Also, the substrates and products of ptDNA replication are generally assumed to be circular molecules. Linear or partly linear ptDNA molecules were detected in our present study using pulsed-field gel electrophoresis and Southern blotting of ptDNA restricted with ‘single cutter’ restriction enzymes. These linear DNA molecules show discrete end points which were mapped using appropriate probes. One possible explanation of discrete ends would be that they represent origins of replication. Indeed, some of the mapped ends correlate well with the known origins of replication of tobacco plastids, i.e. both of the oriA sequences and—less pronouncedly—with the oriB elements. Other ends correspond to replication origins that were described for Oenothera hookeri, Zea mays, Glycine max and Chlamydomonas reinhardtii, respectively, while some of the mapped ends were not described previously and␣might therefore represent additional origins of replication. 相似文献
20.
Giambattista Brocchi’s (1814) monograph (see Dominici, Evo Edu Outreach, this issue, 2010) on the Tertiary fossils of the Subappenines in Italy—and their relation to the living molluscan fauna—contains a theoretical,
transmutational perspective (“Brocchian transmutation”). Unlike Lamarck (1809), Brocchi saw species as discrete and fundamentally stable entities. Explicitly analogizing the births and deaths of species
with those of individual organisms (“Brocchi’s analogy”), Brocchi proposed that species have inherent longevities, eventually
dying of old age unless driven to extinction by external forces. As for individuals, births and deaths of species are understood
to have natural causes; sequences of births and deaths of species produce genealogical lineages of descent, and faunas become
increasingly modernized through time. Brocchi calculated that over 50% of his fossil species are still alive in the modern
fauna. Brocchi’s work was reviewed by Horner (1816) in Edinburgh. Brocchi’s influence as a transmutational thinker is clear in Jameson’s (1827) “geological illustrations” in his fifth edition of his translation of Cuvier’s Theory of the Earth (read by his student Charles Darwin) and in the anonymous essays of 1826 and 1827 published in the Edinburgh New Philosophical Journal—which also carried a notice of Brocchi’s death in 1827. The notion that new species replace older, extinct ones—in what today
would be called an explicitly phylogenetic context—permeates these essays. Herschel’s (1830) discussion of temporal replacement of species and the modernization of faunas closely mirrors these prior discussions. His
book, dedicated to the search for natural causes of natural phenomena, was read by Charles Darwin while a student at Cambridge.
Darwin’s work on HMS Beagle was in large measure an exploration of replacement patterns of “allied forms” of endemic species
in time and in space. His earliest discussions of transmutation, in his essay February 1835, as well as the Red Notebook and the early pages of Notebook B (the latter two written in 1837 back in England), contain Brocchi’s analogy, including
the idea of inherent species longevities. Darwin’s first theory of the origin of species was explicitly saltational, invoking
geographic isolation as the main cause of the abrupt appearance of new species. We conclude that Darwin was testing the predicted
patterns of both Brocchian and Lamarckian transmutation as early as 1832 at the outset of his work on the Beagle. 相似文献