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A composite index, based on function analysis and including thirteen sub-indices, was developed to assess the overall quality of urban and urbanized beaches in the Mediterranean area. The aggregation of components and sub-indices was based on two questionnaires completed by beach users and experts. Applying the new Beach Quality Index (BQI) demonstrated that the quality of beaches could be improved. In general, the strongest aspects of the beaches assessed were those related to short-term user demand, and the weakest were those related to the consequences of human pressure on the area, in particular, erosion problems. The composite index is intended to be used together with Environmental Management Beach Systems (EMBs) as a hierarchical management scorecard and in monitoring programs. This new tool could also make planning more proactive by synthesizing the state of the most important beach processes.  相似文献   
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The hypothesis of disease-related large mammal extinction has new support. A unique pathologic zone of resorption was first noticed in a Hiscock Mammut americanum metacarpal. The pathognomonic zone of resorption was present in fifty-nine (52%) of 113 skeletons with feet available for examination. Metacarpals and metatarsals were most commonly affected. Associated rib periosteal reaction is highly suggestive of tuberculosis and the foot lesions were identical to that documented in Bison as pathognomonic for tuberculosis. Recognizing that only a portion of animals infected by infectious tuberculosis develop bone involvement, the high frequency of the pathology in M. americanum suggests that tuberculosis was not simply endemic, but actually pandemic, a hyperdisease. Pandemic tuberculosis was one of several probable factors contributing to mastodon extinction.  相似文献   
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In this study, we tested the hypothesis that the importance of water flow for skeletal growth (rate) becomes higher with increasing irradiance levels (i.e. a synergistic effect) and that such effect is mediated by a water flow modulated effect on net photosynthesis. Four series of nine nubbins of G. fascicularis were grown at either high (600 μE m−2 s−1) or intermediate (300 μE m−2 s−1) irradiance in combination with either high (15–25 cm s−1) or low (5–10 cm s−1) flow. Growth was measured as buoyant weight and surface area. Photosynthetic rates were measured at each coral’s specific experimental irradiance and flow speed. Additionally, the instantaneous effect of water flow on net photosynthetic rate was determined in short-term incubations in a respirometric flowcell. A significant interaction was found between irradiance and water flow for the increase in buoyant weight, the increase in surface area, and specific skeletal growth rate, indicating that flow velocity becomes more important for coral growth with increasing irradiance levels. Enhancement of coral growth with increasing water flow can be explained by increased net photosynthetic rates. Additionally, the need for costly photo-protective mechanisms at low flow regimes could explain the differences in growth with flow.  相似文献   
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Imprinting Disorders (ImpDis) are a group of congenital conditions caused by aberrant imprinting resulting in disturbed expression of parentally imprinted genes. ImpDis are rarely associated with major malformations, but pre- and/or postnatal growth and nutrition are often affected. In some ImpDis, behavioral, developmental, metabolic and neurological symptoms might present in the perinatal context or later in life, and in single ImpDis, there is a higher risk of tumors in childhood. Prognosis depends in part on the molecular cause of each ImpDis, but due to high clinical variability and (epi)genetic mosaicism, predicting the clinical outcome of a pregnancy solely based on the underlying molecular disturbance is difficult. Therefore, interdisciplinary care and treatment approaches play an important role in the management and decision making of affected pregnancies, especially taking into account fetal imaging in addition to genetic findings. Prenatal findings influence perinatal management, and thereby improve the prognosis of ImpDis associated with severe but sometimes transient clinical complications in the neonatal period. Therefore, prenatal diagnosis can be crucial for appropriate management not only to the pregnancy itself but might also have a life-long effect.  相似文献   
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Forests offer good possibilities for the sequestration of carbon dioxide. This service can be commodified by the introduction of carbon (dioxide) credits, which can be traded on a carbon market. The premise of this paper is that the traditional economic view on the construction of these carbon markets is a too simplistic one, particularly, because it neglects the social meaning of a carbon market for developing countries. From their viewpoint as suppliers of carbon credits such a market has a broader meaning. It must be seen as a social mechanism for improving both the living conditions of local people and a more encompassing improvement of the environment than climate as such. What initially might be labelled as a carbon market might better be understood as a more encompassing 'green market'. The agreement between Costa Rica and Norway, officially known as the Reforestation Conservation Activities Implemented Jointly Project (RFCAIJP) represents a clear example of a green market. In this paper, we study the development, characteristics and benefits of that market, asking the question what lessons can be learned from this first practical experiences. More specifically we focus on the conditions that have made this type of agreement successful.  相似文献   
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