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1.
Bird specimens collected by 19th century explorer and ornithologist Prince Maximilian of Wied-Neuwied form one of the foundation collections of the American Museum of Natural History in New York. However, parts of his collection remained in Germany and came to the Museum Wiesbaden. Since Wied described numerous new species without designating types, some of these specimens might be type material. Here we present a catalog of the 30 Wiesbaden specimens associated with him and discuss their potential type status. We conclude that 17 individuals in 11 species are potential type specimens that should be considered in future taxonomic work. 相似文献
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H. Elenga O. Peyron R. Bonnefille D. Jolly R. Cheddadi J. Guiot V. Andrieu S. Bottema G. Buchet J.-L. De Beaulieu A. C. Hamilton J. Maley R. Marchant R. Perez-Obiol M. Reille G. Riollet L. Scott H. Straka D. Taylor E. Van Campo A. Vincens F. Laarif H. Jonson 《Journal of Biogeography》2000,27(3):621-634
Pollen data from 18,000 14C yr bp were compiled in order to reconstruct biome distributions at the last glacial maximum in southern Europe and Africa. Biome reconstructions were made using the objective biomization method applied to pollen counts using a complete list of dryland taxa wherever possible. Consistent and major differences from present‐day biomes are shown. Forest and xerophytic woods/scrub were replaced by steppe, both in the Mediterranean region and in southern Africa, except in south‐western Cape Province where fynbos (xerophytic scrub) persisted. Sites in the tropical highlands, characterized today by evergreen forest, were dominated by steppe and/or xerophytic vegetation (cf. today’s Ericaceous belt and Afroalpine grassland) at the last glacial maximum. Available data from the tropical lowlands are sparse but suggest that the modern tropical rain forest was largely replaced by tropical seasonal forest while the modern seasonal or dry forests were encroached on by savanna or steppe. Montane forest elements descended to lower elevations than today. 相似文献
4.
G. Karrer 《Plant Ecology》1985,59(1-3):199-209
Five plant communities contrasting in successional status and human impact from the southern part of the ‘Wienerwald’ (Austria) are analyzed using vegetation relevés, spectra of area types and a newly proposed disjunction quotient. A climax community (Asperulo-Fagetum), a subclimax community (Querco-Carpinetum s.l.), an anthropogenous substitute community (Mesobromion) and two natural, non-climax permanent communities (Euphorbio saxatilis-Pinetum nigrae and Fumano-Stipetum eriocaulis) are recognized. The disjunction quotient is defined as the number of partial (discontinous) areas divided by the size of the total area of distribution of a species. In particular, the average disjunction quotients of the species in the first two communities reflect relatively table environments only slightly influenced by man, with many ancient, stable taxa. These communities are characterized by species with well-delimited, stable distribution areas. The species in the Mesobromion community have very low average disjunction quotients as its component species are widely and continuously distributed and are often promoted by man. In contrast to these communities, the species linked to the natural permanent, non-climax communities of extreme habitats, have high distribution quotients i.e. small, disconinuous areas; this illustrates the relic character of these plant communities and of the eastern edge of the Alps is a whole. Using the highly variable disjunction quotient of all species and communities examined, the concepts of climax and permanent communities (of different origin) are discussed with regard to European conditions. 相似文献
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Claudio Orizio Renza Perini Arsenio Veicsteinas 《European journal of applied physiology and occupational physiology》1989,58(5):528-533
The contracting muscle generates a low frequency sound detectable at the belly surface, ranging from 11 to 40 Hz. To study the relationship between the muscular sound and the intensity of the contraction a sound myogram (SMG) was recorded by a contact sensor from the biceps brachii of seven young healthy males performing 4-s isometric contractions from 10% to 100% of the maximal voluntary contraction (MVC), in 10% steps. Simultaneously, the electromyogram (EMG) was recorded as an index of muscle activity. SMG and EMG were integrated by conventional methods (iSMG and iEMG). The relationship between iSMG and iEMG vs MVC% is described by parabolic functions up to 80% and 100% MVC respectively. Beyond 80% MVC the iSMG decreases, being about half of its maximal value at 100% MVC. Our results indicate that the motor unit recruitment and firing rate affect the iSMG and iEMG in the same way up to 80% MVC. From 80% to 100% MVC the high motor units' discharge rate and the muscular stiffness together limit the pressure waves generated by the dimensional changes of the active fibres. The muscular sound seems to reflect the intramuscular visco-elastic characteristics and the motor unit activation pattern of a contracting muscle. 相似文献
7.
The experiment was conducted to investigate the human thermoregulatory responses during rest, exercise and recovery atT
a 20°C and 60% R.H. under the conditions of wearing two different types of clothing. Six healthy men wore two types of clothing: one covering the whole body area except the head (Type A, weight 1656 g), and the other covering only the trunk, upper arms and thighs (Type B, weight 996 g). The level of rectal temperature was kept significantly higher in Type B than in Type A during rest and recovery. The increased and decreased rates of rectal temperature during exercise and recovery were significantly greater in Type A than in Type B, respectively. These findings are discussed from the viewpoint of the differences of skin temperatures of the extremities between Type A and Type B. 相似文献
8.
K. C. Malhotra T. S. Vasulu Y. S. Dikshitulu R. C. Gupta 《International Journal of Anthropology》1992,7(1):23-40
An attempt was made to investigate dermatoglyphic variation between four sex-crimes (SC) and four sex and other crime (SOC) convicts. These were compared with 10 endogamous and 11 penal populations. The results indicate that the two closely related sex crime cases IPC-363 and IPC 366 («kidnap» and «abducting») show wide differences in dermatoglyphic characters. A comparison of sex crimes with sex and other crime cases showed least differences in the case of IPC-363, IPC-363 KC and in IPC 366 and IPC-366 AC but wide differences in IPC-354 («molestation») cases. The dendrograms suggest that the eight sex crime cases cluster together and are different from other endogamous and penal populations. The significant low mean finger ridge count observed in the case of IPC-366 is in agreement with other studies, suggesting a strong association between crime (sex) and dermatoglyphics. 相似文献
9.
Maria Zeydel Karen Puglia Mahboubeh Eghbali Jane Fant Sam Seifter Olga O. Blumenfeld 《Cell and tissue research》1991,265(2):353-359
Summary In the heart of the adult rat, fibroblasts are mainly responsible for the synthesis and deposition of the collagenous matrix. Because these cells in vitro may serve as an important model system for studies of collagen metabolism in heart tissue, we have cultured and characterized rat-heart fibroblasts from young adult and old animals. Conditions included use of media of different compositions with and without addition of ascorbate. Cell used were either cultured directly from fresh tissues or thawed previously frozen cells. Cultured cells were studied with respect to growth properties, morphology and ultrastructure and patterns of collagen. Heart fibroblasts generally resembled fibroblasts cultured from other tissues, but were more like skeletal muscle fibroblasts in that they deposited, in addition to type I collagen, type IV collagen and laminin. The fibroblasts showed a typical appearance in phase-contrast microscopy and electron microscopy. In the case of cells grown with added ascorbate, aligned collagen fibrils in the extracellular matrix showed a periodicity typical of type I collagen. The deposition of type I collagen occurred only in medium supplemented with ascorbate, and in that circumstance increased as a function of time past confluence; this was independent of the age of the animal from which the cells were obtained or of other changes of medium composition studied. Immunofluorescence studies with specific antibodies revealed that the cells deposited types I and IV collagens, laminin and fibronectin. In contrast to the case of type I collagen, the deposition of type IV collagen occurred in cells grown either with or without ascorbate. Direct observation of type IV collagen is consistent with the previous finding of type IV mRNA in cardiac fibroblasts in situ and in freshly isolated populations of these cells. 相似文献
10.
Hiroyuki Uno Yumiko Ohno Tsuneo Yamada Kensaku Miyamoto 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,169(2):231-239
Summary The responses of neurons in field L in the auditory neostriatum of the mynah bird, Gracula religiosa, were recorded during presentation of intact or manipulated mimic voices. A typical mimic voice konnichiwa elicited responses in most of the neurons. Neurons in the input layer (L2) of field L showed many peaks on peristimulus time histograms while those in other layers (L1 and L3) exhibited only one or two peaks. Several neurons in L1 and L3 responded only to the affricative consonant /t/ in the intact mimic voices. They did not respond to the affricative consonant in the isolated segment or to the one in the playbacked voice in reverse. Forty-five percent of the neurons (33/ 73) decreased in firing rates at the affricative consonant in the isolated segment compared with in the intact voice. Some of these neurons, in which neither the affricative consonant in the isolated segment nor bursts of noise alone elicited responses, exhibited clear phasic responses to /t/ in the case when bursts of noise with particular central frequencies preceded the affricative consonant. The responsiveness of these neurons appears to receive temporal facilitation. These results suggest that these neurons code the temporal relationship of speech sound.Abbreviations
HVc
hyperstriatum ventrale, pars caudale
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TFN
temporally facilitated neuron
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TSN
temporally suppressed neuron 相似文献