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101.
In order to make existing private housing more energy efficient, various policies aim at influencing decisions made by homeowners regarding renovation and retrofitting in Scandinavia. Presenting two case studies from Denmark and Norway, we take one step back and observe the whole process of keeping a home habitable. Inspired by theories of Tim Ingold and Elizabeth Shove, we suggest calling this process “the practice of dwelling.” Rather than focusing on decisions and acts pertaining to retrofitting alone, we observe how maintenance and retrofitting are parts of an ongoing practice of dwelling. The cases demonstrate how decisions can be understood as embedded in the practice of dwelling, and how a readiness for decisions regarding retrofitting is created, or not, in this practice. We suggest shifting focus from the outcome of decisions, to attention toward the process that leads to readiness for making the decision in the first place.  相似文献   
102.
Summary The vertical velocity variations of longitudinal and transverse waves in the earth's interior in the depth range of 413 to 2800 km are put into mathematical form. Expressions of the velocities in terms of power functions of the radius are found to conform closely to the given velocities, as well as to be very simple in applications. Examples of the use of such formulas are given, including calculations of travel times and of radial velocity gradients.  相似文献   
103.
The Eyjafjöll AD 2010 eruption is an extraordinary event in that it led to widespread and unprecedented disruption to air travel over Europe – a region generally considered to be free from the hazards associated with volcanic eruptions. Following the onset of the eruption, satellite imagery demonstrated the rapid transportation of ash by westerly winds over mainland Europe, eventually expanding to large swathes of the North Atlantic Ocean and the eastern seaboard of Canada. This small‐to‐intermediate size eruption and the dispersal pattern observed are not particularly unusual for Icelandic eruptions within a longer‐term perspective. Indeed, the Eyjafjöll eruption is a relatively modest eruption in comparison to some of the 20 most voluminous eruptions that have deposited cryptotephra in sedimentary archives in mainland Europe, such as the mid Younger Dryas Vedde Ash and the mid Holocene Hekla 4 tephra. The 2010 eruption, however, highlights the critical role that weather patterns play in the distribution of a relatively small amount of ash and also highlights the spatially complex dispersal trajectories of tephra in the atmosphere. Whether or not the preservation of the Eyjafjöll 2010 tephra in European proxy archives will correspond to the extensive distributions mapped in the atmosphere remains to be seen. The Eyjafjöll 2010 event highlights our increased vulnerability to natural hazards rather than the unparalleled explosivity of the event. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
104.
105.
Fisheries have been vital to coastal communities around the North Sea for centuries, but this semi-enclosed sea also receives large amounts of waste. It is therefore important to monitor and control inputs of contaminants into the North Sea. Inputs of effluents from offshore oil and gas production platforms (produced water) in the Norwegian sector have been monitored through an integrated chemical and biological effects programme since 2001. The programme has used caged Atlantic cod and blue mussels. PAH tissue residues in blue mussels and PAH bile metabolites in cod have confirmed exposure to effluents, but there was variation between years. Results for a range of biological effects methods reflected exposure gradients and indicated that exposure levels were low and caused minor environmental impact at the deployment locations. There is a need to develop methods that are sufficiently sensitive to components in produced water at levels found in marine ecosystems.  相似文献   
106.
The Borrobol Tephra has been identified as one of the key tephra horizons for the Lateglacial time period but it also exemplifies many of the promises and problems of tephrochronology. Additional horizons with similar major element composition and approximately the same age have been identified around the North Atlantic region. Here, we revisit the Borrobol Tephra identified at two Swedish sites, Hässeldala port and Skallahult, and also the Borrobol type‐site in Scotland. We present the first set of minor element data (trace and rare earth analyses) along with new analyses of major elements from these three sites. The analysed minor and the trace elements have a similar signature; however, the glass from the Scottish type‐site seems to imply two populations. To answer if this truly represents two populations, or if it reflects magmatic differentiation additional and larger data sets of minor elements are needed. The new major elements are compared to other Borrobol‐type tephras identified in the North Atlantic region. Our results are in line with earlier investigations, which showed no differences in major elements. Further, comparison of minor elements from glass analyses from our sites with those for eruptions associated with Icelandic central volcanoes implies an Icelandic origin for the Borrobol‐type tephras.  相似文献   
107.
This study defines the Mio-Pliocene to present-day stress regime acting at the northeastern corner of the eastern Mediterranean region along the Karasu Valley (i.e., the Amanos Range), taking in the Antakya, Osmaniye and Kahramanmaras provinces. The inversion slip vectors measured on fault planes and chronologies between striations indicate that the stress regime varied from transpressional initially to transtensional, having consistent NW- and NE-trending σHmax (σ1) and σHmin (σ3) axes, respectively; there are significantly different mean stress-ratio (Rm) values however. The older mean stress state is characterized by N151±11°E-trending σ1 and N59±12°E-trending σ3 axes, and by a mean arithmetic Rm value of 0.76, indicating that the regional stress regime is transpressional. The younger stress regime is characterized by N154±8°E-trending σ1 and N243±8°E-trending σ3 axes, and by a mean arithmetic Rm value of 0.17, indicating a transtensional character for this regional stress regime. The low R values of the stress deviators related to the recent stress state reflect normal-component slips. The earthquake focal mechanism inversions confirm that the younger stress regime continues into the Recent. The inversion identifies a transtensional stress regime representing strike-slip and an extensional stress state with a consistent NE-trending σHmin (σ3) axis. These stress states are characterized by N66°E and N249°E-trending σ3 axes, respectively. Both significant regional stress regimes induce left-lateral displacement along the southern part of the East Anatolian Fault (EAF, or Amanos Fault). The temporal change, probably in Quaternary time, within the regional stress regime—from transpression to transtension—resulted from the coeval influences of subduction processes in the west–southwest (i.e., along the Cyprus arc), continental collision in the east, and westward escape of the Anatolian block.  相似文献   
108.
Room temperature and low temperature Mössbauer and optical absorption spectroscopic data on six natural chloritoids characterized by means of electron microprobe and X-ray powder diffraction techniques are presented. Two narrow quadrupole doublets with widths of 0.25–0.29 mm/s assigned to Fe2+ in a relatively large octahedral site and Fe3+ in a smaller octahedral site, are observed in the Mössbauer spectra. Polarized optical absorption spectra reveal three main absorption bands. A broad absorption band at 16,300 cm?1, which is strongly polarized in EX and EY and shows a linear increase in integral absorption with increasing [Fe2+] [Fe3+] concentration product, is assigned to a Fe2++Fe3+→Fe3++Fe2+ charge transfer transition. This band displays also a temperature dependence different from that of single ion d?d transitions. Two absorption bands at 10,900 cm?1 and 8,000 cm?1 are, on the basis of compositional dependence and energy, assigned to Fe2+ in the large M(1B) octahedra of the brucite-type layer in chloritoid. Combined spectroscopic evidence and structural and chemical considerations support a distribution scheme for ferrous and ferric iron which orders the Fe2+ ions in the M(1B) octahedra and the Fe3+ ions in the small M(1A) octahedral sites. Both types of octahedra are found in the brucite type layer of chloritoid.  相似文献   
109.
The increase in population and the improvement of life standards are stretching the boundaries between water-energy-land management, and demanding innovative and holistic solutions. This article proposes an approach for increasing the water availability of two or more water basins taking into consideration land use and wind patterns, and was named Land, Water, and Wind Watershed Cycle (L3WC). This approach can be applied to one watershed or a combination of watersheds. In the first case, if wind patterns blow mainly in the opposite direction of the main river flow, plantations with high water demand should be focused on the lowest part of the basin. The transpired moisture would then return to the basin with the wind and possibly increase the water availability of the basin. Applying this method to a series of basins, water is transposed from one basin to another, used for irrigated agriculture, returned to the atmosphere with evapotranspiration and pushed back to the basin where the water was extracted by the wind. Case studies of this methodology are presented in the São Francisco basin and between the Tocantins, Amazonas, and Paraná basins and the São Francisco basin in Brazil. The São Francisco basin was selected because it is located in a dry region, its flow has considerably reduced in the past decade and because the trade winds blow constantly from the ocean into the continent all year around. L3WC is a strategy to plan the allocation of water consumption in a watershed, taking into account wind patterns to support the sustainable development of a region. It has the potential of increasing water availability and creating a climate change adaptation mechanism to control the climate and reduce vulnerability to climatic variations.  相似文献   
110.
Prey selection and knowledge of the amounts of water processed by the early stages of the common jellyfish Aurelia aurita may at certain times of the year be crucial for understanding the plankton dynamics in marine ecosystems with mass occurrences of this jellyfish. In the present study we used two different methods (“clearance method” and “ingestion-rate method”) to estimate the amount of water cleared per unit of time of different types and sizes of prey organisms offered to A. aurita ephyrae and small medusae. The mean clearance rates of medusae, estimated with Artemia sp. nauplii as prey by both methods, agreed well, namely 3.8 ± 1.4 l h? 1 by the clearance method and 3.2 ± 1.1 l h? 1 by the ingestion-rate method. Both methods showed that copepods (nauplii and adults) and mussel veligers are captured with considerably lower efficiency, 22 to 37% and 14 to 30%, respectively, than Artemia salina nauplii. By contrast, the water processing rates of ephyrae measured by the clearance method with A. salina nauplii as prey were 3 to 5 times lower than those measured by the ingestion-rate method. This indicates that the prerequisite of full mixing for using the clearance method may not have been fulfilled in the ephyrae experiments. The study demonstrates that the predation impact of the young stages of A. aurita is strongly dependent on its developmental stage (ephyra versus medusa), and the types and sizes of prey organisms. The estimated prey-digestion time of 1.3 h in a steady-state feeding experiment with constant prey concentration supports the reliability of the ingestion-rate method, which eliminates the negative “container effects” of the clearance method, and it seems to be useful in future jellyfish studies, especially on small species/younger stages in which both type and number of prey can be easily and precisely assessed.  相似文献   
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