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61.
Short-term effects of municipal solid waste compost amendments on soil carbon and nitrogen content, some enzyme activities and genetic diversity 总被引:2,自引:0,他引:2
Carmine Crecchio Maddalena Curci Rosaria Mininni Patrizia Ricciuti Pacifico Ruggiero 《Biology and Fertility of Soils》2001,34(5):311-318
Municipal solid waste (MSW) composts have been frequently used as N and C amendments to improve soil quality and to support plant growth, with the additional benefit of reducing waste disposal costs. However, attention has been paid to the risks of MSW use for the soil environment. The presence of heavy metals in MSW composts can affect some microbiological characteristics of soil such as the structure of the soil microbiota, which are responsible for the transformations making nutrients available to plants. The effects of MSW compost and mineral-N amendments in a 2-year field trial on some physical-chemical properties, some enzyme activities and the genetic diversity of cropped plots (sugar beet-wheat rotation) and uncropped plots were investigated. Variations of pH were not statistically related to MSW compost and mineral-N amendments, or to the presence of the crop. Amendment with MSW compost increased the organic C and total N contents, and dehydrogenase and nitrate reductase activities of soil. In cropped plots amended with MSW compost, dehydrogenase activity was positively correlated with #-glucosidase activity, and both enzyme activities with organic C content. No MSW compost dosage effect was detected. No effects were observed on denaturing gradient gel electrophoresis and amplified rDNA restriction analysis patterns, indicating that no significant change in the bacterial community occurred as a consequence of MSW amendment. 相似文献
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Paolicelli RC Bolasco G Pagani F Maggi L Scianni M Panzanelli P Giustetto M Ferreira TA Guiducci E Dumas L Ragozzino D Gross CT 《Science (New York, N.Y.)》2011,333(6048):1456-1458
Microglia are highly motile phagocytic cells that infiltrate and take up residence in the developing brain, where they are thought to provide a surveillance and scavenging function. However, although microglia have been shown to engulf and clear damaged cellular debris after brain insult, it remains less clear what role microglia play in the uninjured brain. Here, we show that microglia actively engulf synaptic material and play a major role in synaptic pruning during postnatal development in mice. These findings link microglia surveillance to synaptic maturation and suggest that deficits in microglia function may contribute to synaptic abnormalities seen in some neurodevelopmental disorders. 相似文献
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Settleability of dry and wet weather flow samples from a combined sewer system was examined by settling column tests, in order to improve understanding of settling processes and obtain information for design of settling tanks. In fact, these tests mimic the actual settling processes and allow evaluating total suspended solids (TSS) removal by settling. Therefore, it is also possible to assess, indirectly, removals of other pollutants, such as heavy metals, which are generally transported by solid particles in sewage. Towards this end, dry and wet weather flow samples were collected in the Liguori Channel catchment and analyzed in the laboratory for Water Supply and Sewerage (Acquedotti e Fognature) of the University of Calabria for TSS concentrations according to the Standard Methods. The settleability study revealed that removals of TSS in dry weather samples (i.e., sanitary sewage) were greater than in wet weather samples (WW), using the same experimental procedures. In particular, 65% of TSS was removed in dry weather samples at a depth of 3?m for a detention time of 40?min; while in wet weather samples the comparable removal efficiency was less than 60%. 相似文献
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Julieta R. Mendieta Carmela Fimognari Gustavo R. Daleo Patrizia Hrelia María G. Guevara 《Fitoterapia》2010,81(5):329-335
StAPs are potato aspartic proteases with cytotoxic activity against plant pathogens and spermatozoa. StAPs cytotoxic activity is selective, since these proteins do not exert toxic effect on plant cells and erythrocytes. In this work, we investigated the capacity of StAPs to exert cytotoxicity on human leukaemia cells. Obtained results show that StAPs induce apoptosis on Jurkat T cells after a short time of incubation in a dose-dependent manner. However, no significative effect on the T lymphocytes viability was observed at all StAPs incubation times and concentrations tested. These results suggest that StAPs can be conceptually promising leads for cancer therapy. 相似文献
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Pistocchi R Guerrini F Pezzolesi L Riccardi M Vanucci S Ciminiello P Dell'Aversano C Forino M Fattorusso E Tartaglione L Milandri A Pompei M Cangini M Pigozzi S Riccardi E 《Marine drugs》2012,10(1):140-162
The Northern Adriatic Sea is the area of the Mediterranean Sea where eutrophication and episodes related to harmful algae have occurred most frequently since the 1970s. In this area, which is highly exploited for mollusk farming, the first occurrence of human intoxication due to shellfish consumption occurred in 1989, nearly 10 years later than other countries in Europe and worldwide that had faced similar problems. Until 1997, Adriatic mollusks had been found to be contaminated mostly by diarrhetic shellfish poisoning toxins (i.e., okadaic acid and dinophysistoxins) that, along with paralytic shellfish poisoning toxins (i.e., saxitoxins), constitute the most common marine biotoxins. Only once, in 1994, a toxic outbreak was related to the occurrence of paralytic shellfish poisoning toxins in the Adriatic coastal waters. Moreover, in the past 15 years, the Adriatic Sea has been characterized by the presence of toxic or potentially toxic algae, not highly widespread outside Europe, such as species producing yessotoxins (i.e., Protoceratium reticulatum, Gonyaulax spinifera and Lingulodinium polyedrum), recurrent blooms of the potentially ichthyotoxic species Fibrocapsa japonica and, recently, by blooms of palytoxin-like producing species of the Ostreopsis genus. This review is aimed at integrating monitoring data on toxin spectra and levels in mussels farmed along the coast of the Emilia-Romagna region with laboratory studies performed on the species involved in the production of those toxins; toxicity studies on toxic or potentially toxic species that have recently appeared in this area are also reviewed. Overall, reviewed data are related to: (i) the yessotoxins producing species P. reticulatum, G. spinifera and L. polyedrum, highlighting genetic and toxic characteristics; (ii) Adriatic strains of Alexandrium minutum, Alexandrium ostenfeldii and Prorocentrum lima whose toxic profiles are compared with those of strains of different geographic origins; (iii) F. japonica and Ostreopsis cf. ovata toxicity. Moreover, new data concerning domoic acid production by a Pseudo-nitzschia multistriata strain, toxicity investigations on a Prorocentrum cf. levis, and on presumably ichthyotoxic species, Heterosigma akashiwo and Chattonella cf. subsalsa, are also reported. 相似文献
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Domenico Caivano Francesco Birettoni Alessandro Fruganti Mark Rishniw Patrizia Knafelz N. Sydney Moïse Francesco Porciello 《Journal of Veterinary Cardiology》2012,14(3):431-444
ObjectivesInterventional cardiac procedures are traditionally performed using fluoroscopy, or, more recently, transesophageal echocardiography (TEE). Neither modality is widely available to practicing cardiologists worldwide. We examined whether balloon valvuloplasty of pulmonic stenosis (PS) and transarterial occlusion of patent ductus arteriosus (PDA) in dogs could be performed safely with transthoracic echocardiography (TTE).AnimalsA prospective consecutive case series of 26 client-owned dogs with PS (n = 10) and PDA (n = 16).MethodsThe cardiovascular procedures were performed using TTE. Each dog was positioned on a standard echocardiography table in right lateral recumbency (dogs with PS) or left lateral recumbency (dogs with PDA). Guide wires, balloon catheters, Amplatz® Canine Ductal Occluder (ACDO) delivery sheaths, and ACDO were imaged by standard echocardiographic views optimized to allow visualization of the defects and devices.ResultsProcedures were performed successfully without major complications in 20 dogs. In 2 dogs (German shepherds) with Type III PDA, ACDO placement was unsuccessful; 2 other German Shepherds were excluded from the procedure because their ductal diameters, measured echocardiographically, exceeded the limits of the maximal ACDO size. Two dogs weighing ≤3.5 kg had suboptimal echocardiographic visualization of the PDA and were considered too small for safe ACDO deployment. All intravascular devices at the level of the heart and great vessels appeared hyperechoic on TTE image and could be clearly monitored and guided in real-time.ConclusionsWe have demonstrated that TTE monitoring can guide each step of pulmonic balloon valvuloplasty and PDA occlusion without fluoroscopy. 相似文献