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1.
Maritime Spatial Planning (MSP) needs to incorporate spatial information on human impacts. As human activities and uses increase in marine and coastal waters around the world, pressures in ecosystems are also increasing, leading to multiple adverse effects on different species and habitats. The European Directive on MSP aims to achieve an integrated approach to marine governance, whilst securing and maintaining the healthy status of marine and coastal waters, in accordance with the Marine Strategy Framework Directive. The latter requires Member States to develop assessments not only on pressures and impacts, but also on the state of the marine environment and then take measures towards reaching a Good Environmental Status by 2020.The Portuguese Maritime Spatial Plan – Plano de Ordenamento do Espaço Marítimo (POEM) was developed between 2009 and 2012. In 2014 a law establishing the Basis for the Spatial Planning and Management of the National Maritime Space was enacted and in 2015 the framework for the elaboration of a new national Maritime Spatial Plan, named Situation Plan, was established. Portugal will face, in the next five years, the challenge of planning and managing its marine space, whilst promoting its sustainable use and protection.This study adapted a cumulative effects assessment model to understand how the impacts from multiple threats affect the marine and coastal ecosystems and, how this information can be used to improve the management process. Information was gathered on intensity and distribution of activities and uses for the Portuguese continental subdivision marine area, quantified and mapped their cumulative impacts in marine ecosystems, and overlapped with the POEM. Results show that impacts are spreading from the coast up to the Contiguous Zone. Higher scores appear in Transitional and Coastal Waters in the north (Viana do Castelo/Figueira da Foz), centre (Peniche/Setúbal) and south (Lagos/Faro). In some areas with higher ranks, statutes of nature conservation are already in place, but potential activities may still occur on top of existing ones. This study shows that the adapted model is a helpful tool to clarify ocean planning, identify areas of potential conflicts among users and support the decision making process.  相似文献   
2.
A charcoalified fossil flower bud of a new genus and species (Teixeiria lusitanica) is described from the Early Cretaceous of Portugal. The flower is actinomorphic and unisexually male. At the base of the bud there are several bracts of different sizes, which are followed by sepal-like and petal-like tepals. Bracts and perianth organs seem to be arranged spirally and to exhibit transitions between different organ categories. The androecium has numerous stamens in two sizes, but with unclear arrangement. Pollen is small and tricolpate with a perforate tectum and a densely columellate infratectal layer. No carpels or remains of carpels could be observed on the floral axis. Teixeiria lusitanica shows most affinities to members of Ranunculales. There are also some similarities with Berberidopsis (Berberidopsidaceae, Berberidopsidales) and members of the Saxifragales (Hamamelidaceae and Daphniphyllaceae).  相似文献   
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Middle Permian Pseudoalbaillella from the Xiaodong area in South China were studied using fossil morphology. Short forms of Pseudoalbaillella fusiformis (Holdsworth and Jones), Pseudoalbaillella internata Wang, and Pseudoalbaillella monacantha (Ishiga and Imoto), characterized by a short and skirt-like pseudoabdomen, were confirmed. We conclude that the short forms were derived from their respective species by breaking off during disruptive processes. If this is true, there may be structurally weakened parts in the pseudoabdomen.  相似文献   
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Population density data on depleted and endangered wildlife species are essential to assure their effective management and, ultimately, conservation. The European wildcat is an elusive and threatened species inhabiting the Iberian Peninsula, with fragmented populations and living in low densities. We fitted spatial capture–recapture models on camera-trap data, to provide the first estimate of wildcat density for Portugal and assess the most influential drivers determining it. The study was implemented in Montesinho Natural Park (NE Portugal), where we identified nine individuals, over a total effort of 3,477 trap-nights. The mean density estimate was 0.032 ± 0.012 wildcat/km2, and density tended to increase with distance to humanized areas, often linked to lower human disturbance and domestic cat presence, with forest and herbaceous vegetation cover and with European rabbit abundance. Although, this density estimate is within the range of values estimated for protected areas elsewhere in the Iberian Peninsula, our estimates are low at the European level. When put in context, our results highlight that European wildcats may be living in low population densities across the Iberian Mediterranean biogeographic region. No phenotypic domestic or hybrid cats were detected, suggesting potentially low admixture rates between the two species, although genetic sampling would be required to corroborate this assertion. We provide evidence that Montesinho Natural Park may be a suitable area to host a healthy wildcat population, and thus be an important protected area in this species' conservation context.  相似文献   
7.
A canonical variate analysis was used to summarize the distribution pattern of 30 species of dung beetles (Scarabaeinae) from 162 sites in the Iberian peninsula (Spain and Portugal) in relation to 4 site variables. The best separation of beetle species, obtained using a xerothermic climatic index, was into 3 groups called “mediterranean”, “unrestricted” and “temperate”. Little further separation was achieved using altitude, dung type or soil type. These data are used to select dung beetles for introduction to south-western Australia for bush fly control.
Résumé On a fait appel à l'analyse de variables canoniques pour résumer le plan de distribution, relatif à 4 variables de localité, de 30 espèces de bousiers (Scarabaeinae) de 162 localités de la Péninsule ibérique (l'Espagne et le Portugal). La meilleure division des espèces, obtenue à l'aide d'un indice xérothermique climatique, se faisait en 3 groupes désignés respectivement comme “méditerranéen”, “ubiquiste” et “tempéré”. Peu de séparation supplémentaire a été obtenue en ayant recours à des facteurs d'altitude, de nature de la bouse ou de type de sol. Ces données ont été employées pour aider à la sélection de bousiers destinés à être introduits en Australie Occidentale pour y combattreMusca vetustissima Walker[Diptera].
  相似文献   
8.
This review summarizes present knowledge of the bacterial cell cycle with particular emphasis on Escherichia coli. We discuss data coming from three different types of approaches to the study of cell extension and division: The search for discrete events occurring once per division cycle. It is generally agreed that the initiation and termination of DNA replication and cell septation are discrete events; there is less agreement on the sudden doubling in rate of cell surface extension, murein biosynthesis and the synthesis of membrane proteins and phospholipids. We discuss what is known about the temporal relationship amongst the various cyclic events studied. The search for discrete growth zones in the cell envelope layers. We discuss conflicting reports on the existence of murein growth zones and protein insertion sites in the inner and outer membranes. Elucidation of the mechanism regulating the initiation of DNA replication. The concept of "critical initiation mass" is examined. We review data suggesting that the DNA is attached to the envelope and discuss the role of the latter in the initiation of DNA replication.  相似文献   
9.
M Reboud-Ravaux 《Biochimie》1985,67(12):1197-1216
Considerable interest in plasminogen activators as human thrombolytic drugs has stimulated rapid biotechnologic progresses. These enzymes have been classified in two immunochemically distinct groups: "urokinase-like" activators or u-PA which do not interact with fibrin and "tissue activator-like" activators or t-PA which interact with fibrin. Plasminogen activators are widely distributed in normal and malignant tissues and they are implicated in various physiological and pathological processes. They maintain the functional integrity of the vascular system and their presence may be of importance in tissue remodeling and cell migration. Urokinase and streptokinase are used in human thrombolytic therapy. However, the properties displayed by t-PA suggest that this enzyme may be a superior fibrinolytic agent. The primary structures of urokinase and t-PA are known; both enzymes have been synthesized by DNA technology. In order to produce t-PA in large quantities by gene cloning, intensive studies are conducted by pharmaceutical industries. Clinical trials using t-PA for dissolving thrombi in coronary heart disease, strokes and pulmonary embolism are in progress. This review presents the molecular and structural properties of plasminogen activators, as well as related physiological, pathological and therapeutic aspects.  相似文献   
10.
J Haiech  J Sallantin 《Biochimie》1985,67(5):555-560
Using a learning set of 28 sequences able to bind calcium (each sequence is 12 residues long), we have built two filters by learning on this set. The first filter uses a pattern-matching technique and the second one takes into account the environment of amino-acids. These two filters have been used to find new calcium-binding proteins in a data bank. The results are discussed.  相似文献   
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