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1.
Frida Westgren Tove Hjorth Margareta Uhlhorn Pernille E Etterlin Charles J Ley 《Acta veterinaria Scandinavica》2014,56(1):25
An eleven-year-old Chinese Crested Powder Puff dog presented with polydipsia/polyuria, inappetence, diarrhea and vomiting underwent an ultrasound-guided percutaneous liver biopsy. Two days post-biopsy the clinical condition of the dog acutely deteriorated with fever, dyspnea, ataxia and subcutaneous emphysema. Radiographs and ultrasound showed focal severe hepatic emphysema in the region of the previous liver biopsy. Post-mortem examination revealed chronic hepatitis with dissecting fibrosis, acute hepatitis with hemorrhage and in the hindlimb musculature extensive hemorrhage and necrosis. Pure cultures of the gas producing bacteria Clostridium perfringens were isolated in samples from the hind limb musculature. We propose that the hepatic emphysema in the region of the biopsy site was a result of a clostridial infection. 相似文献
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Gilbert MT Kivisild T Grønnow B Andersen PK Metspalu E Reidla M Tamm E Axelsson E Götherström A Campos PF Rasmussen M Metspalu M Higham TF Schwenninger JL Nathan R De Hoog CJ Koch A Møller LN Andreasen C Meldgaard M Villems R Bendixen C Willerslev E 《Science (New York, N.Y.)》2008,320(5884):1787-1789
The Paleo-Eskimo Saqqaq and Independence I cultures, documented from archaeological remains in Northern Canada and Greenland, represent the earliest human expansion into the New World's northern extremes. However, their origin and genetic relationship to later cultures are unknown. We sequenced a mitochondrial genome from a Paleo-Eskimo human by using 3400-to 4500-year-old frozen hair excavated from an early Greenlandic Saqqaq settlement. The sample is distinct from modern Native Americans and Neo-Eskimos, falling within haplogroup D2a1, a group previously observed among modern Aleuts and Siberian Sireniki Yuit. This result suggests that the earliest migrants into the New World's northern extremes derived from populations in the Bering Sea area and were not directly related to Native Americans or the later Neo-Eskimos that replaced them. 相似文献
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Alsos IG Eidesen PB Ehrich D Skrede I Westergaard K Jacobsen GH Landvik JY Taberlet P Brochmann C 《Science (New York, N.Y.)》2007,316(5831):1606-1609
The ability of species to track their ecological niche after climate change is a major source of uncertainty in predicting their future distribution. By analyzing DNA fingerprinting (amplified fragment-length polymorphism) of nine plant species, we show that long-distance colonization of a remote arctic archipelago, Svalbard, has occurred repeatedly and from several source regions. Propagules are likely carried by wind and drifting sea ice. The genetic effect of restricted colonization was strongly correlated with the temperature requirements of the species, indicating that establishment limits distribution more than dispersal. Thus, it may be appropriate to assume unlimited dispersal when predicting long-term range shifts in the Arctic. 相似文献
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Dynamic plant uptake model applied for drip irrigation of an insecticide to pepper fruit plants 总被引：1，自引：0，他引：1
BACKGROUND: Drip application of insecticides is an effective way to deliver the chemical to the plant that avoids off‐site movement via spray drift and minimizes applicator exposure. The aim of this paper is to present a cascade model for the uptake of pesticide into plants following drip irrigation, its application for a soil‐applied insecticide and a sensitivity analysis of the model parameters. RESULTS: The model predicted the measured increase and decline of residues following two soil applications of an insecticide to peppers, with an absolute error between model and measurement ranging from 0.002 to 0.034 mg kg fw?1. Maximum measured concentrations in pepper fruit were approximately 0.22 mg kg fw?1. Temperature was the most sensitive component for predicting the peak and final concentration in pepper fruit, through its influence on soil and plant degradation rates. CONCLUSION: Repeated simulations of pulse inputs with the cascade model adequately describe soil pesticide applications to an actual cropped system and reasonably mimic it. The model has the potential to be used for the optimization of practical features, such as application rates and waiting times between applications and before harvest, through the integrated accounting of soil, plant and environmental influences. Copyright © 2011 Society of Chemical Industry 相似文献
5.
Ottosen Lisbeth M. Hansen Henrik K. Jensen Pernille E. 《Water, air, and soil pollution》2009,201(1-4):295-304
Water, Air, & Soil Pollution - Desorption of Cu, Cr, Pb, and Zn from industrially polluted soils as a result of acidification is in focus. The eight soils of the investigation vary greatly in... 相似文献
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Tissue architecture and soil fertility controls on decomposer communities and decomposition of roots
Jane Lindedam Jakob Magid Pernille Poulsen Jesper Luxhøi 《Soil biology & biochemistry》2009,41(6):1040-2060
Using complementary techniques we observed great differences in decomposition of mono- and dicot roots (Festuca rubra L., red fescue grass and Trifolium pratense L., red clover) in compost and soil of varying fertility which we attribute both to chemical characteristics and differences in tissue architecture. In our study the lignin contents were equal for the root materials while C-to-N ratios and cellulose-to-lignin ratios were higher in fescue roots. Pictures taken with a scanning electron microscope (SEM) showed that the rippled surface of fescue roots appeared largely intact even after prolonged incubation giving scant support to predominantly cocci bacteria, where an angular grid structure on the surface of intact clover roots rapidly yielded. The clover root cavities became deeper over time and seemed a favourable nest for colonising rod shaped bacteria. In addition the nodules on clover roots were abundantly covered by decomposers early on. SEM pictures as well as bands of microbial DNA from polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) on roots degraded in compost indicate that organisms colonising clover and fescue grass roots are inherently different and to a greater extent connected to the root material than the compost. Respiration data showed that soil fertility compared to root material played a smaller, albeit significant role in determining the decomposition pattern. There was no indication of N limitation in decomposition. On the contrary accumulated respiration was highest from infertile soils and had significantly lower T½ compared to nutrient rich soils, most likely due to a higher maintenance respiration and lower substrate use efficiency of the decomposers. DGGE showed that infertile soils as well as recalcitrant material both led to a larger diversity of decomposers compared to fertile soils or easily degradable materials. All together this study demonstrated a positive relationship between microbial diversity and stress resulting in higher diversity in the recalcitrant the roots and the infertile soils. 相似文献
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Jens Kjerulf Petersen Camille Saurel Pernille Nielsen Karen Timmermann 《Aquaculture International》2016,24(3):857-878
Effects of excess loading of nutrients to the marine environment can be mitigated by mussel cultures, basically through nutrient removal from the marine environment when shellfish are harvested. Shellfish farming also provide other goods and services to the marine environment primarily through the impact on water transparency caused by shellfish filtration. There is an increasing awareness of the mitigation potential in mussel culture in relation to eutrophication, but so far practical examples of culture on full scale devoted to mitigation are few. Further, impact of mussel farming on nutrient cycling, e.g. in the sediments below the culture units, has raised concerns. In this review, we clarify concepts in relation to nutrient mitigation and discuss goods and services delivered by mussel mitigation cultures and their impact on an ecosystem scale based primarily on results from studies in heavily eutrofied estuaries. A multi-criteria approach for site selection is presented based on experiences from Danish waters, and economic aspects of mitigation cultures are analysed in relation to use of the produced mitigation mussels. Future perspectives for extractive cultures are discussed in relation to source of excess nutrients. 相似文献
9.
Hydrocarbon and Toxic Metal Contamination from Tank Installations in a Northwest Greenlandic Village
Janne Fritt-Rasmussen Pernille Erland Jensen Rune Haubo Bojesen Christensen Ingela Dahll?f 《Water, air, and soil pollution》2012,223(7):4407-4416
Contamination from tank installations in the Arctic is an important issue, since tanks are a necessary feature of all communities, and may be a source of local pollution. Soil samples from below and around three tank installations and one reference site in the Northwest Greenlandic village of Tasiusaq were analysed for the total content of hydrocarbons (THC), lead, cadmium and organic content in the soil. Concentrations up to 77,000?mg/kg DW THC were found, mainly as weathered oil products. Elevated levels of lead and cadmium were also found in many of the samples, with concentrations up to 300 and 2?mg/kg DW, respectively. The tank installation areas were contaminated by THC, lead and cadmium compared to the reference site, and parts of the areas were highly contaminated, exceeding the Danish environmental quality criteria. The correlation between lead and cadmium concentrations was significant (p?<?0.01), while no correlation existed between THC and organic matter. Small spills from daily use of the tank installations are suggested to be the source of the THC contamination, whereas the lead and cadmium contamination is suggested to originate primarily from the plume of smoke from waste incineration. 相似文献
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Low genetic variation for Dendrobaena octaedra from Greenland compared to populations from Europe and North America: Refuge or selection? 总被引：2，自引：0，他引：2
Pernille Liland Hansen Martin Holmstrup Mark Bayley Vibeke Simonsen 《Pedobiologia》2006,50(3):225-234
The genetic relationship of 345 specimens of the parthenogenetic lumbricid Dendrobaena octaedra from Greenland, Canada and Europe were analysed by means of isozymes. The results showed that populations from Greenland were markedly different from Canadian and European populations, suggesting that dispersal between Greenland and the continents has been much more restricted in the past than dispersal between North America and Europe. This observation supports to the notion that Greenland populations have persisted for a long period and perhaps have survived the last glacial period in ice-free refugia. A highly significant positive correlation was seen between diversity measured either as mean haploid diversity or clonal diversity and mean temperature of the annual coldest month. These results indicate that temperature might cause selection in colder climates or that sexual processes in D. dendrobaena could have been active recently on an evolutionary time scale. 相似文献