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161.
Daniel C. W. Tsang Theo C. M. Yip Irene M. C. Lo 《Journal of Soils and Sediments》2011,11(7):1221-1233
Purpose
Most previous studies focused on the metal extraction efficiency of chelant-enhanced soil washing under various operational conditions; however, one of the keys to cost-effective field application is to maintain a high throughput rate (i.e., short washing time) while achieving the treatment objectives. Therefore, this study presented a conceptual model for simulating the kinetic extraction of heavy metals and evaluated its sensitivity analysis to the predetermined parameter values in five soils with different initial metal distributions. 相似文献162.
Irene Sartini Beata Łebkowska-Wieruszewska Andrzej Lisowski Amnart Poapolathep Helen Owen Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2020,43(1):26-32
The purpose of this study was two-fold: I) to determine the pharmacokinetic profile of meloxicam (MLX) in geese after intravenous (IV) and oral (PO) administration and II) to assess tissue residues in muscle, heart, liver, lung, and kidney. Ten clinically normal female Bilgorajska geese were divided into two groups (treated, n = 8; control, n = 2). Group 1 underwent a 3-phase parallel study with a 1-week washout period. In phase I, animals received MLX (0.5 mg/kg) by IV administration; the blood was collected up to 48 hr. In phases II and III geese were treated orally at the same dosage for the collection of blood and tissue samples, respectively. Group 2 served as control. After the extraction procedure, a validated HPLC method with UV detection was used for plasma and organ analysis. The plasma concentrations were quantifiable up to 24 hr after both the administrations. The elimination phase of MLX from plasma was similar in both the administration groups. The clearance was slow (0.00975 L/hr*Kg), the volume of distribution small (0.0487 L/kg), and the IV half-life was 5.06 ± 2.32 hr. The average absolute PO bioavailability was 64.2 ± 24.0%. Residues of MLX were lower than the LOQ (0.1 µg/kg) in any tested tissue and at any collection time. The dosage used in this study achieved the plasma concentration, which provides analgesia in Hispaniolan Amazon parrots for 5 out of 24 hr after PO administration. MLX tissue concentrations were below the LOD of the assay in tissue (0.03 µg/ml). A more sensitive technique might be necessary to determine likely residue concentrations in tissue. 相似文献
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Precision Agriculture - Soil acidification is a growing problem in semi-arid agroecosystems. In the state of Montana, USA, soil pH levels below 5.5 have been documented in nearly half of the... 相似文献
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Brock J. Bergseth Adrian Arias Michele L. Barnes Iain Caldwell Amber Datta Stefan Gelcich Sam H. Ham Jacqueline D. Lau Cristina Ruano-Chamorro Patrick Smallhorn-West Damian Weekers Jessica Zamborain-Mason Joshua E. Cinner 《Fish and Fisheries》2023,24(4):695-704
Advocates, practitioners and policy-makers continue to use and advocate for marine protected areas (MPAs) to meet global ocean protection targets. Yet many of the worlds MPAs, and especially no-take MPAs, are plagued by poaching and ineffective governance. Using a global dataset on coral reefs as an example, we quantify the potential ecological gains of governing MPAs to increase compliance, which we call the ‘compliance gap’. Using ecological simulations based on model posteriors of joint Bayesian hierarchical models, we demonstrate how increased compliance in no-take MPAs could nearly double target fish biomass (91% increases in median fish biomass), and result in a 292% higher likelihood of encountering top predators. Achieving these gains and closing the compliance gap necessitates a substantial shift in approach and practice to go beyond optimizing enforcement, and towards governing for compliance. This will require engaging and integrating a broad suite of actors, principles, and practices across three key domains: (i)) harnessing social influence, (ii) integrating equity principles, and (iii) aligning incentives through market-based instruments. Empowering and shaping communication between actor groups (e.g., between fishers, practitioners, and policy-makers) using theoretically underpinned approaches from the behavioural sciences is one of the most essential, but often underserved aspects of governing MPAs. We therefore close by highlighting how this cross-cutting tool could be further integrated in governance to bolster high levels of compliance in MPAs. 相似文献
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Six modified-live (ML) infectious laryngotracheitis (ILT) vaccine viruses, three reference strains, and 18 field isolates were compared by restriction endonuclease analysis of their DNA. Viral DNA digestion patterns were established for vaccine viruses using restriction endonucleases PstI, BamHI, KpnI, and HindIII. Using these enzymes, five of six ML vaccine viruses had identical restriction endonuclease cleavage patterns. Vaccine viruses had distinct patterns compared with ILT virus reference strains Illinois-N71851, Cover, and NVSL. Restriction endonuclease cleavage patterns of 18 field isolates of ILT virus, obtained from ILT outbreaks in North Carolina, were indistinguishable from vaccine viruses. These results suggest a possible role of vaccine or vaccine-like viruses in recent ILT outbreaks. 相似文献
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Specific-pathogen-free chickens orally inoculated at 4 days of age with a moderately pathogenic vaccine strain of infectious bursal disease virus (IBDV) and/or at 5 days of age with Cryptosporidium baileyi oocysts remained free of overt clinical signs throughout a 16-day period postinoculation (PI). The prepatency period for C. baileyi oocyst shedding was shorter in chickens receiving higher numbers of oocysts, but once shedding was detected, there were no obvious differences in shedding patterns among groups receiving 10(3) through 10(6) oocysts. On days 8 and 16 PI, cryptosporidia were located primarily in the bursae of Fabricius. IBDV exposure was associated with bursal follicle atrophy, whereas C. baileyi infection resulted in bursal epithelial hypertrophy and hyperplasia, mild follicle atrophy, and heterophil infiltration of the bursal mucosa. Examination of experimental groups of 30 birds each indicated that concurrent infection with both agents resulted in more severe bursal lesions, more infected birds, and greater numbers of cryptosporidia in infected tissues. At the termination of the trial, 16 days PI, Cryptosporidium infection was associated with a 6% decrease in mean body weight compared with controls. 相似文献