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581.
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
582.
Sergio Hernandez-Trujillo 《Fisheries Oceanography》1999,8(4):284-295
Copepod community structure and abundance of the most abundant species were studied during 15 cruises made between 1982 and 1989 along the west coast of the Baja California Peninsula, Mexico. The number of species and species diversity (Shannon's index) for each sampling station of the oceanographic cruises were obtained. Though the zone was dominated during the year by the tropical copepod component, similarities between El Niño 1982–83 and 1987–88 were observed. Tropical-equatorial populations were added to the regular tropical composition (50%) of the community of copepods resulting in a wide distribution of those populations in 1982–83 and in 1987–88. The scenario in 1984–89 (without 1987–88) was significantly different from both El Niños because of the sea surface temperature, the species diversity, and the tropical copepod component, although 1982 was similar to 1985 in diversity index and number of species. Environmental conditions prevailing along the west coast of Baja California during El Niño indicate that in 1982–83 the effect on the copepod community was greater than during the 1987–88 event. 相似文献
583.
EVALUATION OF MAGNETIC RESONANCE IMAGING GUIDELINES FOR DIFFERENTIATION BETWEEN THORACOLUMBAR INTERVERTEBRAL DISK EXTRUSIONS AND INTERVERTEBRAL DISK PROTRUSIONS IN DOGS 下载免费PDF全文
Steven De Decker Sergio A. Gomes Rowena MA Packer Patrick J. Kenny Elsa Beltran Birgit Parzefall Joe Fenn Devi Nair George Nye Holger A. Volk 《Veterinary radiology & ultrasound》2016,57(5):526-533
Four MRI variables have recently been suggested to be independently associated with a diagnosis of thoracolumbar intervertebral disk extrusion or protrusion. Midline intervertebral disk herniation, and partial intervertebral disk degeneration were associated with intervertebral disk protrusion, while presence of a single intervertebral disk herniation and disk material dispersed beyond the boundaries of the intervertebral disk space were associated with intervertebral disk extrusion. The aim of this retrospective, cross‐sectional study was to determine whether using these MRI variables improves differentiation between thoracolumbar intervertebral disk extrusions and protrusions. Eighty large breed dogs with surgically confirmed thoracolumbar intervertebral disk extrusions or protrusions were included. Randomized MRI studies were presented on two occasions to six blinded observers, which were divided into three experience categories. During the first assessment, observers made a presumptive diagnosis of thoracolumbar intervertebral disk extrusion or protrusion without guidelines. During the second assessment they were asked to make a presumptive diagnosis with the aid of guidelines. Agreement was evaluated by Kappa‐statistics. Diagnostic accuracy significantly improved from 70.8 to 79.6% and interobserver agreement for making a diagnosis of intervertebral disk extrusion or intervertebral disk protrusion improved from fair (κ = 0.27) to moderate (κ = 0.41) after using the proposed guidelines. Diagnostic accuracy was significantly influenced by degree of observer experience. Intraobserver agreement for the assessed variables ranged from fair to excellent and interobserver agreement ranged from fair to moderate. The results of this study suggest that the proposed imaging guidelines can aid in differentiating thoracolumbar intervertebral disk extrusions from protrusions. 相似文献
584.
Fungyi Chow Juan Macchiavello Sergio Santa Cruz Erika Fonck Jorge Olivares 《Journal of the World Aquaculture Society》2001,32(2):215-220
An evaluation was made on a seasonal basis of the effect of the marine macroalga culture Gracilaria chilensis on concentrations of some soluble and particulate wastes emitted during tank cultures of a fish Isacia conteptionis , an oyster Crassostrea gigas , and a sea urchin Loxechinus albus species. The animals were each cultured in separate tanks, and effluent from each was directed through separate tanks, which contained dense cultures of the Gracilaria chilensis . Inflow-outflow monitoring was conducted for the presence of nitrate, nitrite, ammonium, and phosphate. Also evaluated were particulate nitrogen and phosphate. The most significant wastes were ammonium from the fish culture and nitrate from the oyster culture. These were completely removed from the water, with minor exceptions, by the alga during all seasons of the year. Lesser amounts of soluble phosphate and nitrite, arising from the fish cultures, were also removed. Of the particulate matter, only nitrogen was in evidence from the fish cultures in the summer. It was concluded that Gracilaria chilensis culture was highly efficient at biofiltration of the soluble nutrients tested but had little effect on particulate emissions. The best growth of Gracilaria chilensis occurred in the ammonium-rich effluent from the fish culture. 相似文献
585.
Miguel Cid Sonia Pereira Cristina Cabaleiro Franco Faoro Antonio Segura 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):23-30
Grapevine leafroll-associated virus 3 (GLRaV-3) is a mealybug-transmissible ampelovirus. Though the transmission mechanism has been described as semipersistent
on the basis of temporal parameters, definitive proof of this mechanism has never been provided. In the present study, we
carried out preliminary assays to establish the location of the virus in its vector, Planococcus citri. After dissecting the insects, GLRaV-3 was detected by means of IC-RT-PCR in the salivary glands, intestine and Malpighian
tubes, but not in the sucking apparatus. Immunogold labelling of the capsid protein revealed the presence of the virus in
some cells of the primary salivary glands, but not in the alimentary channel of the stylet, or in the accessory salivary glands.
The strong labelling of the electron-dense secretion vesicles in some cells of the primary salivary glands, together with
the non-detection of the virus in the sucking apparatus suggests that the transmission mechanism may be different from that
previously described. We propose a circulative transmission mechanism based on a specific transportation route for the viral
particles from the midgut or hindgut to the salivary glands. As the transmission mechanism is generally a common feature of
a viral genus, the existence of a circulative transmission mechanism for other mealybug-transmitted ampeloviruses is expected.
Organ by organ analysis of GLRaV-1, another ampelovirus not transmissible by P. citri, showed the absence of the virus in the salivary glands, thus providing further, though indirect, evidence in favour of circulative
transmission for this virus genus. 相似文献
586.
Luis Souza Lima de Souza Reis Paulo Eduardo Pardo Eunice Oba Sergio do Nascimento Kronka Neuza Maria Frazatti-Gallina 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(2):189-192
Matricaria chamomilla CH12 is a phytotherapeutic or homeopathic product, which has been used to reduce stress. Here, we examined its effect on preventing handling stress in bovines. Sixty Nelore calves were randomly distributed into two equal groups. One group was administered Matricaria chamomilla CH12 in diet and the other the ''control'' was not. Animals in both groups were maintained unstressed for 30 days to adjust to the feeding system and pasture, and were then stressed by constraint on the 31th, 38th, 45th and 60th experimental days. Blood samples were taken on these days after animals had been immobilization in a trunk contention for 5 min. Stress was followed by analyzing serum cortisol levels. These peaked on the 45th day and then decreased, but not to baseline, on the 60th day. On the 45th day cortisol levels were significantly lower in animals fed Matricaria chamomilla CH12, suggesting that this product reduces stress. These effects may be a consequence of its inhibiting cortisol production and its calming and anxiolytic effects. 相似文献
587.
John G. Brayan Paul R. Haddad Gerald J. Sharp Sergio Dilli James M. Desmarchelier 《Pest management science》1992,34(3):215-219
Carbaryl was extracted from aged samples of rice, maize, peas and sunflower seeds using hexane, acetone and methanol. The quantities of insecticide extracted from the grain by acetone and methanol were much higher than that extracted by hexane for all four products. Methanol extracted higher levels of carbaryl than acetone from maize and peas but for rice and sunflower seeds the results were similar for the two solvents. Extraction by simply standing the whole grain in solvent for 48 h generally resulted in similar extracted levels of carbaryl to those obtained using more exhaustive techniques, such as grinding the grain or Soxhlet extraction. However, grinding or Soxhlet extraction removed the pesticide from the grain more rapidly. 相似文献
588.
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
589.
590.
In fruit trees, understanding genetic determinisms of architectural traits is considered as a promising manner to control
vegetative development and yield regularity. In this context, our study aimed to classify 2-year-old apple hybrids on the
basis of their architectural traits. From a fine phenotyping, trees were described as tree graphs, including topological and
geometric information. To evaluate the similarity between trees, comparison methods based on edit operations (substitution,
insertion and deletion) were carried out. Distance between two tree graphs was computed by minimising the sum of the costs
of the edit operations applied to transform one tree into another. Two algorithms for the comparison of unordered and partially
ordered tree graphs were applied to a sub-sample of the population, taking into account several geometric attributes. For
each comparison, a dissimilarity matrix was computed, and subsequently trees were clustered. A local interpretation of the
matched entities was proposed through schematic representations of the trees, and similarities between trees were analysed
within and between clusters. The tree graphs, both unordered or partially ordered and whether the attributes were considered
or not, were grouped, by clustering, according to the number of entities per tree. The robustness of the unordered comparison
was demonstrated by its application to the whole population, since it provided results similar to those obtained on the sub-sample.
Further developments towards a higher relative weight of geometric versus topological information are discussed in the perspective
to define an architectural ideotype in apple. 相似文献