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561.
Canobbio Sergio Mezzanotte Valeria Sanfilippo Umberto Benvenuto Federica 《Water, air, and soil pollution》2009,203(1-4):359-368
Water, Air, & Soil Pollution - Mobilization of arsenic (As) in the subsurface environment can result in elevated concentrations of As in groundwater and potential human exposure and adverse... 相似文献
562.
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564.
Campos Isidro González-Gómez Laura Villodre Julio Calera Maria Campoy Jaime Jiménez Nuria Plaza Carmen Sánchez-Prieto Sergio Calera Alfonso 《Precision Agriculture》2019,20(2):214-236
Precision Agriculture - This paper explored the ability of remote sensing (RS) and meteorological data to map the variability of yield/biomass in cultivated wheat (Triticum aestivum). The... 相似文献
565.
Mirjam A.F. Ros-Tonen Tinde van Andel Carla Morsello Kei Otsuki Sergio Rosendo Imme Scholz 《Forest Ecology and Management》2008
There is more to sustainable forest management than reduced impact logging. Partnerships between multiple actors are needed in order to create the institutional context for good forest governance and sustainable forest management and stimulate the necessary local community involvement. The idea behind this is that the parties would be able to achieve more jointly than on their own by combining assets, knowledge, skills and political power of actors at different levels of scale. This article aims to demonstrate by example the nature and variety of forest-related partnerships in Brazilian Amazonia. Based on the lessons learned from these cases and the authors’ experience, the principal characteristics of successful partnerships are described, with a focus on political and socioeconomic aspects. These characteristics include fairly negotiated partnership objectives, the active involvement of the public sector as well as impartial brokers, equitable and cost-effective institutional arrangements, sufficient and equitably shared benefits for all the parties involved, addressing socioeconomic drawbacks, and taking measures to maintain sustainable exploitation levels. The authors argue that, in addition to product-oriented partnerships which focus on sustainable forest management, there is also a need for politically oriented partnerships based on civil society coalitions. The watchdog function of these politically oriented partnerships, their awareness-raising campaigns regarding detrimental policies and practices, and advocacy for good forest governance are essential for the creation of the appropriate legal and political framework for sustainable forest management. 相似文献
566.
Herlinde Dumez Enrique Gallardo Stephane Culine Joan Carles Galceran Patrick Sch?ffski Jean P. Droz Sonia Extremera Sergio Szyldergemajn Aude Fléchon 《Marine drugs》2009,7(3):451-463
The objective of this exploratory, open-label, single-arm, phase II clinical trial was to evaluate plitidepsin (5 mg/m2) administered as a 3-hour continuous intravenous infusion every two weeks to patients with locally advanced/metastatic transitional cell carcinoma of the urothelium who relapsed/progressed after first-line chemotherapy. Treatment cycles were repeated for up to 12 cycles or until disease progression, unacceptable toxicity, patient refusal or treatment delay for >2 weeks. The primary efficacy endpoint was objective response rate according to RECIST. Secondary endpoints were the rate of SD lasting ≥ 6 months and time-to-event variables. Toxicity was assessed using NCI-CTC v. 3.0. Twenty-one patients received 57 treatment cycles. No objective tumor responses occurred. SD lasting <6 months was observed in two of 18 evaluable patients. With a median follow-up of 4.6 months, the median PFR and the median OS were 1.4 months and 2.3 months, respectively. The most common AEs were mild to moderate nausea, fatigue, myalgia and anorexia. Anemia, lymphopenia, and increases in transaminases, alkaline phosphatase and creatinine were the most frequent laboratory abnormalities. No severe neutropenia occurred. Treatment was feasible and generally well tolerated in this patient population; however the lack of antitumor activity precludes further studies of plitidepsin in this setting. 相似文献
567.
Maria A. Arribére Linda M. Campbell Andrea P. Rizzo Marina Arcagni Jorge Revenga Sergio Ribeiro Guevara 《Water, air, and soil pollution》2010,212(1-4):167-182
The Northern Patagonian Andean range shared by Chile and Argentina has numerous glacial oligotrophic lakes protected in a series of National Parks. Recent baseline surveys indicated that concentrations in muscle and liver tissues from various fish species from across Nahuel Huapi and Los Alerces National Parks in Argentina were comparable or higher than similar fish species from other parts of the world. As a result, Lake Moreno, in Nahuel Huapi National Park, was chosen to investigate multiple element sinks, trends, and transfer in a representative Patagonia aquatic food web. The metals and metalloids Ag, As, Ba, Br, Cs, Co, Cr, Fe, Hg, K, Na, Rb, Se, and Zn were analyzed in three size plankton fractions, submerged macrophytes, biofilm, insect larvae, amphipods, decapods, gastropods (snails), annelids (earthworms), and forage fish. Except for nanoplankton (10–53 μm; small-celled algae, rotifers) and microplankton (53–200 μm; larger algae, ciliates, zooplankton nauplii), which share elemental compositional similarities, each taxon category had its own distinctive compositional pattern, revealed by principal component analysis. Nano- and microplankton tend to be relatively elevated in some metals, including As, Co, Cr, Fe, Hg, Zn, and Rb, followed by biofilm. Shredder-scrapper Trichoptera (caddisflies) have higher concentration of most of the studied elements than other insect larvae taxa, especially carnivorous Odonata (Anisoptera, dragonflies), which were associated with lower elemental contents. Those trends point to an overall tendency for biodiminishing element concentrations with trophic level in the benthos of Lake Moreno. 相似文献
568.
Robert G. Nelson Sergio A. Duarte Michael P. Masser 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3-4):171-177
Abstract This study analysed the benefits and costs of three airlift aeration regimes — continuous (24 hr), partial (9 hr/night plus emergencies), and no aeration — for channel catfish in cages. Data from four field studies included four dependent variables based on size at harvest, and six independent variables. Four regression models were fit with a modified Cobb‐Douglas production function in a Seemingly Unrelated Regression system. Yield projections from the production function were then used in a stochastic economic model with prices and variable costs expressed as triangular distributions. Results indicated that none of the aeration methods was preferred to the others by either first‐ or second‐degree stochastic dominance criteria, although partial aeration was the risk‐neutral choice. A power analysis was used to demonstrate that an impractical number of replicates would be needed to detect a difference between partial and continuous aeration that was both economically and statistically significant. 相似文献
569.
Maria Albrizio Antonio C. Guaricci Serena Milano Francesco Macrì Giulio Aiudi 《Fish physiology and biochemistry》2014,40(4):997-1009
In aquaculture, unfavourable conditions experienced during early development may have strong downstream effects on the adult phenotype and fitness. Sensitivity to stress, leading to disease, reduced growth and mortality, is higher in larvae than in adult fish. In this study, conducted on sea bream (Sparus aurata), we evidenced the presence of the mu opioid receptor in gametes and larvae at different developmental stages. Moreover, we evaluated the possibility of reducing the effects of artificially produced stress, altering temperature, salinity and pH, by naloxone (an opioid antagonist) and calcium. Results evidenced that mu opioid receptor is present in larvae and in gametes of both sexes and that, during larval growth, its expression level changes accordingly; furthermore, naloxone/calcium association is efficacious in increasing the survival period of treated larvae compared to controls. We conclude that in sea bream rearing, the use of naloxone/calcium against stress can improve fish farming techniques by reducing larval mortality and consequently increasing productivity. 相似文献
570.
Fabiana Guzmán Fabián Giolitti Franco Fernández Claudia Nome Sergio Lenardon Luis Conci 《European journal of plant pathology / European Foundation for Plant Pathology》2014,138(4):679-683
Sunflower (Helianthus annuus L.) plants showing capitulum with virescence, phyllody and flower malformation, shortened internodes and abnormal branches were found in a field in Pedro Luro (Buenos Aires province, Argentina). Pleomorphic bodies resembling phytoplasmas were observed in sieve tube elements of symptomatic plants but not in healthy ones. DNA from all symptomatic sunflower plants analysed yielded, in direct PCR with phytoplasma universal primers P1/P7 and R16F2n/R2, fragments of expected size 1.8 kb and 1.2 kb, respectively. The phytoplasma associated with the disease, was named Sunflower Phyllody (SunPhy). Real and putative RFLP of the 16S rDNA showed the affiliation of SunPhy to 16SrIII (X-disease group), subgroup J. The 16S rDNA sequence from SunPhy showed the highest identity (99 %) with 16SrIII members and the phylogenetic tree confirmed a closer relationship to subgroup J of the 16SIII ribosomal group. This is the first report of a phytoplasma related to the 16SrIII group affecting sunflower. 相似文献