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Urban habitats, particularly wastelands and brownfields, maintain rich biodiversity and offer habitat for many species, even rare and endangered taxa. However, such habitats are also under socio-economic pressures due to redevelopment for housing and industrial uses. In order to maintain urban biodiversity, it is currently unknown how much open area must be preserved and whether conservation is possible without complete exclusion from economic development. In this study, we applied a simulation model based on species distribution models for plants, grasshoppers, and leafhoppers to investigate planning options for urban conservation with special focus on business areas. Altogether, we modelled the occurrence of 81 species of the urban species pool and analysed settings of different proportions of open sites, different habitat turnover times, and different lot sizes. Our simulations demonstrated that dynamic land use supports urban biodiversity in terms of species richness and rarity. Setting aside brownfields before redevelopment for a period of on average 15 years supported the highest conservation value. Consequently, we recommend integrating the concept of ‘temporary conservation’ into urban planning for industrial and business areas. This concept requires habitat to be destroyed by redeveloping brownfield sites to built-up sites, but simultaneously creating new open spaces due to abandonment of urban land uses at other locations. This maintains a spatio-temporal mosaic of different successional stages ranging from pioneer to pre-forest communities. 相似文献
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Jun M Shao Y Ho CT Koetter U Lech S 《Journal of agricultural and food chemistry》2003,51(21):6340-6346
The degradation profile of glucosamine bulk form stressed at 100 degrees C for 2 h in an aqueous solution was studied. Column chromatography of acetylated product mixture led to isolation of two pure compounds (1b and 2b) and a mixture of at least three isomers (3b). 1a and 2a were identified as 5-(hydroxymethyl)-2-furaldehyde (5-HMF) and 2-(tetrahydroxybutyl)-5-(3',4'-dihydroxy-1'-trans-butenyl)pyrazine, respectively, by utilizing a variety of analytical techniques, such as GC-MS, LC-MS, on-line UV spectrum, (1)H and (13)C NMR, and DEPT, as well as (1)H-(1)H COSY. 3a was identified as 2-(tetrahydroxybutyl)-5-(2',3',4'-trihydroxybutyl)pyrazine, commonly known as deoxyfructosazine. In addition, glucosamine solid dosage form was exposed to 40 degrees C/75% relative humility for 10 weeks. Methanol extract of glucosamine solid dosage form was analyzed after acetylation by LC-MS, resulting in degradants 3b and 4b. 3a and 4a were, therefore, determined as deoxyfructosazine and 2,5-bis(tetrahydroxybutyl)pyrazine (fructosazine), respectively. Furthermore, the mechanisms of formation of identified degradation products are proposed and briefly discussed. 相似文献
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Wood AC Fine DM Spier AW Eyster GE 《Journal of the American Veterinary Medical Association》2006,228(12):1901-1904
CASE DESCRIPTION-A 12-week-old female English Springer Spaniel was evaluated for lethargy, vomiting, and pyrexia 1 week after treatment of patent ductus arteriosus (PDA) via coil occlusion. CLINICAL FINDINGS-Test results were consistent with septicemia, and the assumption was made that the PDA occlusion coils were infected. Radiography revealed partial migration of the coil mass into the pulmonary artery and signs of congestive heart failure. TREATMENT AND OUTCOME-After successful treatment of the septicemia and heart failure, surgical removal of the coils and resection of the PDA were undertaken. Although the coil that embolized to the pulmonary vasculature was left in place, the dog's clinical signs resolved. CLINICAL RELEVANCE-This case highlights the fact that as PDA coil occlusion devices become more widely used in dogs, practitioners must be prepared to treat implant infections aggressively, with both medical and surgical interventions if necessary. 相似文献
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Aviram M Volkova N Coleman R Dreher M Reddy MK Ferreira D Rosenblat M 《Journal of agricultural and food chemistry》2008,56(3):1148-1157
We have analyzed in vivo and in vitro the antiatherogenic properties and mechanisms of action of all pomegranate fruit parts: peels (POMxl, POMxp), arils (POMa), seeds (POMo), and flowers (POMf), in comparison to whole fruit juice (PJ). Atherosclerotic E 0 mice consumed POM extracts [200 microg of gallic acid equivalents (GAE)/mouse/day] for 3 months. Blood samples, peritoneal macrophages (MPM), and aortas were then collected. All POM extracts possess antioxidative properties in vitro. After consumption of PJ, POMxl, POMxp, POMa, or POMf by E (0) mice, the atherosclerotic lesion area was significantly decreased by 44, 38, 39, 6, or 70%, respectively, as compared to placebo-treated group, while POMo had no effect. POMf consumption reduced serum lipids, and glucose levels by 18-25%. PJ, POMxl, POMxp, POMf, or POMa consumption resulted in a significant decrement, by 53, 42, 35, 27, or 13%, respectively, in MPM total peroxides content, and increased cellular paraoxonase 2 (PON2) activity, as compared to placebo-treated mice. The uptake rates of oxidized-LDL by E (0)-MPM were significantly reduced by approximately 15% after consumption of PJ, POMxl, or POMxp. Similar results were obtained on using J774A.1 macrophage cell line. Finally, pomegranate phenolics (punicalagin, punicalin, gallic acid, and ellagic acid), as well as pomegranate unique complexed sugars, could mimic the antiatherogenic effects of pomegranate extracts. We conclude that attenuation of atherosclerosis development by some of the POM extracts and, in particular, POMf, could be related to the combined beneficial effects on serum lipids levels and on macrophage atherogenic properties. 相似文献
19.
Fine DM DeClue AE Reinero CR 《Journal of the American Veterinary Medical Association》2008,232(11):1674-1679
OBJECTIVE: To evaluate assessment of circulating amino terminal-pro-B-type natriuretic peptide (NT-proBNP) concentration as a means to discriminate between congestive heart failure and primary pulmonary disease in dogs. DESIGN: Prospective case series. ANIMALS: 46 dogs with signs of respiratory distress or coughing. PROCEDURES: All dogs underwent physical and thoracic radiographic examinations. Dogs with evidence of heart disease (eg, murmur, arrhythmia, or large cardiac silhouette detected by radiography) also underwent echocardiography. Dogs with no evidence of heart disease or failure were included if they underwent bronchoalveolar lavage (with cytologic examination and bacterial culture of the lavage fluid). Blood samples for NT-proBNP assay were obtained within 12 hours of the diagnosis of heart failure or prior to bronchoalveolar lavage in dogs with primary pulmonary disease. Circulating concentrations of NT-proBNP were compared between groups and correlated with radiographic and echocardiographic measures of cardiac size. RESULTS: Congestive heart failure and primary pulmonary disease were diagnosed in 25 and 21 dogs, respectively. Dogs with congestive heart failure had significantly higher median serum or plasma NT-proBNP concentration (2,554 pmol/L; interquartile [25% to 75%] range, 1,651.5 to 3,475.5 pmol/L) than dogs with primary pulmonary disease (357 pmol/L; interquartile range, 192.5 to 565.5 pmol/L). Radiographic vertebral heart score and echocardiographic left atrial-to-aortic diameter ratio were not correlated with NT-proBNP concentration. Left ventricular end-diastolic diameter (measured echocardiographically) and NT-proBNP concentration were weakly correlated. CONCLUSIONS AND CLINICAL RELEVANCE: Serum or plasma NT-proBNP concentration assessment may be useful for discrimination of congestive heart failure from primary pulmonary disease in dogs with respiratory distress or cough. 相似文献
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José M. Herrera Isa de Sá Teixeira Javier Rodríguez-Pérez António Mira 《Landscape Ecology》2016,31(4):731-743