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31.
A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall.  相似文献   
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33.
  1. Sharks are globally exposed to several anthropogenic threats, which, in many cases, have severely reduced their distribution and have impacted populations. In the Mediterranean Sea, because of its long history of exploitation and the relatively short span of scientific monitoring, reconstructing shark baselines is challenging. Many vulnerable species declined in population abundance and geographic distribution before it was possible to adequately track these changes. Consequently, for many of these species, current conservation assessments are now suffering from a severe case of shifting baseline syndrome, whereby their historical occurrence in the area is questioned.
  2. The sand tiger shark (Carcharias taurus) is one of these cases. Characterized by high philopatry, restricted home range, and low interchange between populations, its Mediterranean population may have been severely impacted by the high historical fishing pressure in the region before scientific monitoring began.
  3. In this study, the history of the abundance and distribution of C. taurus in the Mediterranean Sea was reconstructed through a comprehensive search of occurrence records in the literature and in museum collections. Between 1810 and 2008, 31 occurrence records and 54 publications provided information on the presence of the species in the area. These records were sparse but systematic over time and indicated occurrence hot spots in the south‐western Mediterranean Sea and in the eastern Adriatic Sea.
  4. The presence of ten sightings of juveniles from a total of 18 sightings with length information suggested local parturition. Habitat and extinction models indicate that the area has suitable oceanographic conditions for the occurrence of the species and that the species cannot be considered extinct in the Mediterranean Sea. Our study suggests that there is still hope for the recovery of the species and underlines the crucial role of historical investigations to reconstruct the history of large elasmobranchs in the Mediterranean Sea.
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34.
This paper deals with the determination of the pore-size distribution of untreated and thermally modified twin samples of Norway spruce (Picea abies (L.) Karst.) and sycamore maple (Acer pseudoplatanus L.) by means of mercury intrusion porosimetry. The investigations considered oven-dried and at 22 °C and 95 % relative humidity-conditioned samples. A special sample holder and a novel method for evacuation were developed for the measurements. This was necessary both to ensure that samples were positioned at a defined distance and the conditioned samples did not dry in an uncontrolled manner. The results clearly show that the climatic state influences the results. Thermal modification greatly alters the pore-size distribution of spruce. This can be largely attributed to the formation of intercellular spaces in the middle lamella as a result of cell-wall compression due to thermal modification. The alteration of the pore structure of maple due to thermal modification is not as pronounced as that of spruce.  相似文献   
35.
Use of decision support systems (DSS) has thus far been framed as a social process of adoption or technical process of usability. We analyze the development of a DSS as a process of institutionalization of new as well as drift of existing practices. We write an Actor-Network-Theory (ANT) account, i.e. an interpretive study, that follows the traces left by both human and non-human actors (e.g. technology, methodologies, etc.) to understand how a DSS development project institutionalizes DSS technology in several forest management organizations in the German state of Rheinland Pfalz. The research has an innovative value since it uses ANT in the design of a DSS, hence affecting it, while commonly ANT has been used to understand why networks work or do not. Moreover, we use a new technology (PREZITM, www.prezi.com) for the visualization of the whole actor network coherent to the ANT methodology, i.e. “keeping the social flat.” As a result, the development of the ANT account proposed in the present paper, even if still partial, supports the design of new technologies being introduced in current practice and generates an important learning effect thanks to the underpinning interpretative approach.  相似文献   
36.
  1. The protection of ecosystems with high diversity, such as coral reefs, is not an approach that guarantees their conservation. Thus, maintaining connectivity among coral populations over the long term is a strategy that should be adopted in order to protect diversity and ecological processes. Although coral reefs in Colombia are highly diverse, the population genetics baseline data of keystone species such as Orbicella faveolata are limited.
  2. To provide current information about the connectivity between populations of O. faveolata in the Colombian Caribbean, the genetic diversity and distribution of O. faveolata was evaluated with analysis of molecular variance (AMOVA), principal components, and migration estimations using 113 genets distributed in six populations. Also, a genetic structure analysis that included the available data for the Caribbean population was conducted, seeking to understand how the Colombian populations relate to the broader region.
  3. According to the global fixation index (FST) for the Colombian Caribbean, there was no genetic structure (FST = 0.002). Discriminant analysis of principal components (DAPC) showed that Corales del Rosario Archipelago (CR), Este de Isla Fuerte (EIF), San Bernardo Archipelago (SB), and Varadero Reef (VR) were grouped with Oeste de Isla Fuerte (OIF), with Bushnell (BS) representing the most divergent cluster. Migration analysis showed relatively high migration from VR to CR and SB, highlighting the importance of VR as a genetic reservoir for the region. Structure analysis showed that the Colombian population presented a specific genetic identity (FST = 0.254), suggesting that the Colombian Caribbean population could be a peripheral population that contributes significantly to genetic variation and is connected through a complex connectivity process.
  4. In conclusion, the estimated genetic connectivity reflects the influence of sea surface dynamics over the interpopulation exchange dynamics and the role of protected and nonprotected coral reef in the Colombian Caribbean. Thus, the Colombian Caribbean population of O. faveolata could be relevant to the conservation of genetic diversity on a larger scale.
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37.
The Prymnesiophycea Pavlova lutheriwas produced using a traditional technique (batch mode in carboys) and by an innovative technique (semi-continuous mode in alveolarphotobioreactor). Two experimental feedingtrials were carried out with Pacific oyster(Crassostrea gigas) larvae with freshand preserved (4 °C and 1 °C)P. lutheri concentrates used inmonospecific and bispecific diets, incombination with fresh Chaetoceroscalcitrans forma pumilum. Nodifferences in terms of gross composition andlarval performance were noticed between thefresh algae biomass produced by the twotechniques. The low temperatures allowedpreservation of the nutritionalcharacteristics of the P. lutheri freshculture for the time period considered (27days). The P. lutheri concentratespreserved at 4 °C or 1 °C didnot differ substantially in terms ofnutritional value. Larvae fed a monospecificdiet of P. lutheri, both fresh andpreserved, exhibited a modest growth rate (<2.1 µm day–1), in some cases notsignificantly different from that observed inthe unfed larvae (the control), and a lowsurvival rate. In contrast, when Chaetoceros calcitrans forma pumilumwas used as a monospecific diet, good growthperformance (>4.5 µm day–1) and ahigh survival rate (>86%) were observed inlarvae. A substitution of 50% (trial 1) or80% (trial 2) of fresh C. calcitransforma pumilum with the preserved P. lutheri concentrates did not adverselyaffect growth rate or survival of C.gigas larvae.  相似文献   
38.
A greenhouse rhizobox experiment was carried out to quantify the incorporation of 13C- and 15N-labelled rhizodeposits into different soil pools, especially into the rhizosphere microbial biomass, with increasing distances to the root surface of Lolium perenne. Five layers were analysed over 0-4.2 mm distance to an artificial root surface. C and N derived from rhizodeposition were 4.2% of total C and 2.8% of total N in soil at 0-1.0 mm distance and decreased rapidly with increasing distance. Microbial biomass C and N increased significantly towards the roots. At 0-1.0 mm distance microbial biomass C and N accounted for 66% and 29% of C and N derived from rhizodeposition, respectively. These percentages declined with increasing distance to the roots, but were still traceable up to 4.2 mm distance. Only small amounts of root released C and N were found in the 0.05 M K2SO4-extractable fraction. Extractable C and N derived from rhizodeposition varied around means of 4% of total C and N derived from rhizodeposition and increased only marginally with increasing distance to the roots. C derived from rhizodeposition in the non-extractable soil organic matter increased from 65 to 89% of total C derived from rhizodeposition at 0-3.4 mm distance. Conversely, microbial biomass C derived from rhizodeposition decreased from 33 to 4%. N derived from rhizodeposition in the non-extractable soil organic matter increased from 61 to 79% of total N derived from rhizodeposition at 0-2.6 mm distance, followed by a decline to roughly 55% in the two outer layers. Microbial biomass N decreased from 37 to 16% at 0-2.6 mm distance, followed by an increase to roughly 41% in the two outer layers. The C/N ratio of total C and N derived from rhizodeposition as well as that of extractable C and N derived from rhizodeposition increased with increasing distance to the roots to values above 30. In contrast, the C/N ratio of incorporated rhizodeposition C and N into the microbial biomass decreased to values less than 5 at 2.6-4.2 mm distance. The data indicate differential microbial response to C and N derived from rhizodeposition at a high spatial resolution from the root surface. The turnover of C and N derived from rhizodeposition in the rhizosphere as a function of the distance to the root surface is discussed.  相似文献   
39.
gamma-Terpinene (TH), a monoterpene hydrocarbon present in essential oils, retards the peroxidation of linoleic acid (LH). The peroxidation of TH has been shown to yield p-cymene as the only organic product in a chain reaction in which the chain carrier is the hydroperoxyl radical, HOO(.). The peroxidation of LH is well-known to be a chain reaction in which the chains are carried by linoleylperoxyl radicals, LOO., and the products are linoleyl hydroperoxides. The retardation of LH peroxidation by TH has been found to be due to rapid chain termination via a very fast cross-reaction between HOO. and LOO. radicals. This antioxidant mechanism is completely different from the mechanism of antioxidant action of vitamin E. Since vitamin E becomes a prooxidant at high concentrations, the addition of essential oils containing TH to edible lipids may provide an alternative or supplementary strategy for obtaining large increases in their oxidative stability and shelf life, something that cannot be achieved by simply adding more and more vitamin E.  相似文献   
40.
We investigated if Pinus ponderosa plantations in Patagonia are able to produce viable mycorrhizal inocula towards adjacent grasslands, which only harbor endomycorrhizal vegetation. We hypothesized that these inocula have the potential to contribute to the establishment of naturally disseminated seedlings. Also, we determined the main fungal taxa involved in this process. Seven plantations in the onset of their reproductive phase and located in the Patagonian native forest/steppe ecotone (Argentina) were selected. Soil samplings were obtained at nine points along a 450 m long, W-E transect established in each plantation. Soil bioassays were performed in a greenhouse, with P. ponderosa seedlings acting as hosts for mycorrhizal inocula present in soil samples, during 12 months. Mycorrhization percentage, morphotype richness and morphotype composition was determined through morphological evaluation. Viable ecto- and ectendomycorrhizal inocula were found disseminated outside plantations. The amount of mycorrhizal inoculum followed a decreasing function with distance to plantation edges. Mycorrhizal fungal genus Rhizopogon and “E-strain” mycorrhizal types appeared as pioneering taxa regarding seedlings colonization, being the most persistent and frequent symbionts found. Plantations, thus, facilitate the surrounding terrain for newcoming seedlings through the dispersion of mycorrhizal fungal inocula.  相似文献   
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