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We studied the toxicity of copper on Microcystis aeruginosa and Aphanizomenon flos-aquae. The toxicity phenomena can be described by the survival dose relationship which allows us to define the three parameters: threshold concentration (Cs), sensitivity (k) and a NL. 50%. The latter corresponds to the copper concentration which reduces the number of cells at the end of the exponential phase by 50%. A. flos-aquae is very clearly less tolerant than M. aeruginosa to copper. Viable cell counts based on electron transport activity showed that M. aeruginosa cultures can detoxify copper.  相似文献   

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Objective

To analyze the relationship between different test measuring explosive strength and functionality of active women participating in a leisure sport program in order to describe the caracteristics of health status and look for tools for diagnosing and monitoring degenerative process.

Methods

This study was conducted on 102 women physically active and without risk factors. Anthropometric, functional independence and explosive strength tests were applied.

Results

Mean age 60.08±5.35 years; body mass index: 26.81±3.91; percentage of fat: 52.45±4.75; percentage of muscle mass: 37.24±6.77; tests of functional independence: maximum speed (30 meters): 9.39±1.92 s; speed-agility (30 meters): 12.93±1.59 s, and dynamic balance (6 meters): 21.9±8.01 s. Explosive Strength (Bosco test): Squat Jump: 12.23±3.05 cm, Countermovement Jump: 13.18±3.04 cm and Countermovement Jump Arm swing: 14.80±4.01 cm.

Conclusion

The statistical relationships found between body composition, explosive strength and functionality tests, are important tools for diagnosing and monitoring, and could improve the intervention models on the elderly.  相似文献   

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The first Carboniferous conodonts studied from the Cares river section correspond to fifteen species and one subspecies from seven genera, some of them reported from the Picos de Europa Unit for the first time. The conodonts belong to several zones between the upper Tournaisian and the upper Serpukhovian-lower Bashkirian. Furthermore, the species Idiognathodus incurvus Dunn is reported for the first time in the Cantabrian Mountains and southern Europe, from upper Bashkirian or lower Moscovian beds.  相似文献   

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This paper presents the results obtained by lithic analysis of Early Upper Palaeolithic levels in Šandalja II Cave, Istria, Croatia. Technological and typological analysis of stone and typological analysis of bone artefacts have been carried out. Production of flakes in Aurignacian levels (G, F, E and E/F) is dominant, but blade and bladelets production is also present. Blades and bladelets were produced by direct soft hammer technique. Aurignacian people of Šandalja II produced their debitage mainly on local grey chert, which is often patinated. Šandalja II is one of the rare—if not the only—site with Aurignacian industry in eastern Adriatic region. The main reason for absence of such industry at other sites can be seen in scarce population or abandonment of some parts of this region.  相似文献   

10.
Recent ichnological studies revealed two new localities showing dinosaur footprints in the Hettangian Dolomitic Formation from the Causses Basin, southern France. The traces are reported from the northern part of the basin, in Lozère, an area where Lower Jurassic dinosaur ichnites were poorly documented. The surfaces bearing footprints are characterized by a large number of traces. The ichnites are ascribed to Grallator (Hitchcock, 1858), Dilophosauripus (Welles, 1971) and Eubrontes (Hitchcock, 1845) whose trackmakers were theropods. Although numerous tracksites were previously described in the southern part of the Causses Basin, these three ichnotaxa are for the first time observed in association into the Dolomitic Formation.  相似文献   

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A new locality, close to Freiria de Rio Maior, provided a mammalian fauna associated with Charophytes, secds,Ostracods, Gastropods and Urodels. The most abundant remains correspond to a new species: Rotundomys freiriensis. This fauna has been dated as the Upper Vallesian base (MN 10), corresponding to the most recent level with small mammals found in the portuguese Miocene. Thus, the Freiria limestone succession is correlated to Cartaxo, Almoster, etc., limestones which are so developed in the Ribatejo area.  相似文献   

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Located in the south-western Mato Grosso state (Central Brazil), the vast territory of the Cidade de Pedra was continuously occupied since the mid-Holocene by several groups of hunter-gatherers. Rock paintings, lithic industries, ceramics, ornaments, combustion remains (etc.) testify their passages in the many rock art sites discovered since 1983. In this paper are presented the results of the first anthracological analyzes conducted in four of these rock shelters. The studies were realized from macro-remains carbonized from hearths, embers and concentrations. From the taxonomic identification of charcoal, the objectives are to highlight the practices of hunter-gatherers related to the collection of wood and the environment in which they evolved for nearly 5000 years. The results indicate that they practiced an opportunistic collection mainly focused on dry wood available in the vegetation around the sites. They evolved in an environment similar to that currently characterizes the region, a typical flora of the Cerrado Biome and seasonal climate.  相似文献   

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We describe a new titanosaurian braincase (MML-194), from the Upper Cretaceous (middle Campanian-lower Maastrichtian) of Río Negro Province, Argentina. Among titanosaurs, this specimen resembles Bonatitan reigi, more than any other member of the clade; the similarity is based on the supraoccipital protuberance bearing a median groove (also present in Saltasaurus and Rapetosaurus), the prominent basal tubera, the exit for the nerve VII located on the prootic crest, the occipital condyle and the foramen magnum almost of the same width. This material allows to observe some internal structures that are not appreciable in other titanosaurs, such as the pituitary cavity, the dorsum sellae and the foramen for the passage of the internal carotids, among other characters. The specimen MML-194 and Bonatitan were exhumed of same geological unit, the Allen Formation, from which have also been collected fossil eggs assignable to sauropods (megalooliths), for what is not unlikely that some of these taxa has been responsible of the laying of those eggs.  相似文献   

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Organic dinoflagellate cysts are studied from the sedimentary sequence of hole 1-SPS-14A, drilled during oil exploration in the Santos Basin, Brazilian continental margin. The Ariri and Florianópolis Formations (Transitional sequence) do not contain any dinocysts. The oldest found dinocysts occur at the base of the Drift sequence in sediments, within platform carbonates of the Guarujá Formation. Continuous sea-level rise throughout the late Albian and Cenomanian submerged the carbonate platform with the terrigenous input of the Itanhaém Formation. The transgressive phase reached its peak during the Cenomanian/Turonian transition. Pelites were deposited during oceanic anoxic event (OAE-2), consisting the lower part of the Itajaí-Açu Formation. Normal oceanic conditions re-established in the late Turonian. The Brazilian dinocyst assemblage has tethyan affinities. Some species (i.e., Dinopterygium cladoides, Litosphaeridium arundum, Odontochitina rhakodes and Systematophora cretacea) suggest a middle Albian age for the carbonate platform of the Guarujá Formation. The lower part of the Guarujá Formation was not dated by other microfossils. An uppermost Albian or lower Cenomanian age is suggested for the base of the Itanhaém Formation on the basis of species Palaeohystrichophora infusorioides and Ovoidinium verrucosum. The Cenomanian-Turonian boundary cannot be characterized by dinocysts. Species Atopodinium iuvene, which is known from Turonian sediments in Europe, was found at the top of the Itajaí-Açu Formation. The observed dinocyst bioevents (i.e., last occurrence) are correlated with known foraminiferal, nannofossil and other palynological bioevents. The diversity of the assemblages remains constant throughout the various palaeoenvironments as these are reflected by the Guarujá and Itajaí-Açu Formations, but relative abundances of taxa are variable. Genera Coronifera, Florentinia, Ovoidinium, Spiniferites and Trichodinium are abundant in the carbonate platform assemblages (Guarujá Formation). Genera Cribroperidinium and Cyclonephelium are abundant in detrital sediments (Itajaí-Açu Formation). Only one species (Subtilisphaera guarujaensis n. sp.) is restricted to the carbonate platform environment.  相似文献   

18.
Silicified woods of the fern Tempskya riojana Barale and Viera and the Bennettitales Cycadeoidea barbarae Crisafulli nov. sp., found together with undetermined conifer woods, from the NW of Carazuelo, province Soria, are described. This site is located south of the so-called San Saturio fault which runs parallel to Road N-234. The fossil trunks are included in the “Conglomerados poligénicos, areniscas y arcillas” fluviatile sediments, dated as Paleogene. The original source of these fossils could be Tera and/or Oncala Groups, both Early Cretaceous in age and outcropping close by at Fuentetecha, Fuensaúco and North of Soria. Similar plant fossil findings from this region are reported and some mistakes in the geological mapping are analyzed. The Tempskya specimens were histologically poorly preserved, but had enough anatomical characters to be undoubtedly assigned to Tempskya riojana. The new species Cycadeoidea barbarae is described, with fairly well preserved cellular structure, viz., pith, vascular cylinder, cortex, foliar/branch traces, as well as strobili surrounded by foliar scales and apical seminal cones. An important and new aspect of the new species is that it includes morphologically and anatomically preserved both fructifications and vegetative parts, whereas these are usually find separated by other species of Bennettitales.  相似文献   

19.
Spermiogenesis in Urastoma cyprinae (Graff. 1882) involvcs a progressive lengthening of the spermatid. Free flagella are only transitory. The mature spermatozoon is fusibrm. 45μm in length and 2.5 μm in width. It contains two incorporated axonermes of the flatworm 9+"1" pattern, two elongated mitochondria. an elongated nucleus and a row or cortical longitudinal microtubules. Observations on oogenesis concerncd only the immuturc ovary. lmmature oocytes contain few dense granules and accssory cells were not ohserved. Phylogenetic implications of a biflagellate spermatozoon in a Prolecithophora are important. The presence of two 9 +"1" axonemes confirms that Urastoma (and the Prolecithophora) belongs to the taxon Trepaxonemata Ehlers. Previous electron microscope studies on spermitozoa of Prolecithophora (four genera) only dealt with aflagellate spermatozoa. On this basis, Ehlers (1985) proposed two autapomorphics for the taxon Prolecithophora: aflagellate spermatozoon and spermatozoal mitochondrial derivatives with abundant membranes. The present observations on Urastoma contradict these two autapomorphics. The taxon Prolecithophora cannot be defined by autapomorphies of the spermatozoon.  相似文献   

20.
Three species of the genus Paravortex were studied. Spermiogenesis involves progressive lengthening of the spermatid. No centriole nor axoneme were found. Thc mature spermatozoon is threadlike, 30μm long and aflagellate. It contains a nucleus, two longitudinal parallel mitochondria, numerous dense bodies limited by a membrane, a row of cortical microtubules and granules. The spatial arrangement of the microtubules wah deduced from a statistical analysis of their number in transverse section. The microtubules are continuous along the length of the spermatozoon and are arranged along a long cone. The granules, not limited by a membrane, are about 25 nm in diameter. They are arranged in a semicircle and represent a new structure for sperm of Platyhclminthes. A statistical comparison demonstrated that two species may be distinguished by the number of their cortical sperm microtubules. This is the tirst ultrastructural study of an aflagellate spermatozoon in the Rhabdocoela. A rickettsia was found in P. cardii .  相似文献   

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