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Birds are the most diverse vertebrate group in Chile, characterized by low species turnover at the country-size scale (high alpha but low beta diversities), resembling an island biota. We tested whether this low differentiation is valid at a local scale, among six forest habitat types. We detected 25 bird species; avifauna composition was significantly different among habitat types, with five species accounting for 60 % of the dissimilarity. We found a higher level of bird assemblage differentiation across habitats at the local scale than has been found at the country-size scale. Such differentiation might be attributed to structural differences among habitats.  相似文献   
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Phylogeographic patterns among coastal fishes are expected to be influenced by distinct ecological, biological and life history traits, along with historical events and oceanography (past and present). This study focuses on the broad range phylogeography of the Montagu’s blenny Coryphoblennius galerita, a species with well-known ecological features, strictly tied to rocky environments and with limited dispersal capability. Eleven locations from the western Mediterranean to the Bay of Biscay (including the Macaronesian archipelagos) were sampled. Mitochondrial DNA control region (CR) and the first intron of the S7 ribosomal protein gene were used to address the population structure, the signatures of expansion/contraction events retained in the genealogies and potential glacial refugia. The genetic diversity of the Montagu’s blenny was high throughout the sampled area, reaching maximum values in the Mediterranean and western Iberian Peninsula. The results confirmed a marked structure of C. galerita along the sampled area, with a major separation found between the Mediterranean and the Atlantic populations, and suggesting also a separation between the Azores and the remaining Atlantic locations. This study revealed complex and deep genealogies for this species, with Montagu’s blenny populations presenting signatures of events clearly older than the Last Glacial Maximum, with lineages coalescing in early Pleistocene and Pliocene. Three potential glacial refugia where this species might have survived Pleistocene glaciations and from where the recolonization process might have taken place are suggested: South of Iberian Peninsula/North Africa, Mediterranean and Azores.  相似文献   
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Few studies have explored the relationships between nation‐building, disaster risk reduction and climate change adaptation. Focusing on small island developing states, this paper examines nation‐building in Timor‐Leste, a small island developing state that recently achieved independence. Nation‐building in Timor‐Leste is explored in the context of disaster risk reduction, which necessarily includes climate change adaptation. The study presents a synopsis of Timor‐Leste's history and its nation‐building efforts as well as an overview of the state of knowledge of disaster risk reduction including climate change adaptation. It also offers an analysis of significant gaps and challenges in terms of vertical and horizontal governance, large donor presence, data availability and the integration of disaster risk reduction and climate change adaptation for nation‐building in Timor‐Leste. Relevant and applicable lessons are provided from other small island developing states to assist Timor‐Leste in identifying its own trajectory out of underdevelopment while it builds on existing strengths.  相似文献   
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An experimental setup is proposed to test the performance of safety devices based on radio frequency technology. The setup specifically tests devices designed for improving safety in dangerous areas of small size, such as those surrounding power press brakes. Tested here is a radio frequency identification (RFID) prototype, whose main objective is to prevent accidents by sending a stop signal to a machine when a worker’s wrist, bearing an RFID tag, gets too close to the dangerous area. An ABB IRB 2400L robot is used as a reference system; this system is capable of providing millimeter accuracy. A plastic hand and a wristband with at least one passive RFID tag are attached to the end of the robot arm, which emulates the behavior of a human arm. With this robotic approach, it is possible to test trajectories with different velocities and orientations and to simulate several risky situations associated with machine use. Several experiments are presented that were conducted with the RFID prototype, and statistics are reported on the distance detection capability of this safety system with respect to the plane that defines the dangerous area. A matrix approach is proposed for analyzing the robustness of safety devices that are designed to automatically prevent a worker entering in dangerous areas. The results show the benefits that development of a radio frequency device of this class could confer towards increasing worker safety.  相似文献   
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