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11.
Red cell osmotic fragility was studied in 50 blood samples of the fish Scomberomorus maculatus (Mitchill). High levels of mean corpuscular fragility were found and hypotheses are presented to explain this phenomenon. 相似文献
12.
A. C. H. Barreto M. M. Costa A. S. B. Sombra D. S. Rosa R. F. Nascimento S. E. Mazzetto P. B. A. Fechine 《Journal of Polymers and the Environment》2010,18(4):523-531
Banana fibers, as well as other lignocellulosic fibers, are constituted of cellulose, hemicellulose, lignin, pectin, wax and
water soluble components. The abundance of this fiber combined with the ease of its processing is an attractive feature, which
makes it a valuable substitute for synthetic fibers that are potentially toxic. In this work, the structure characterization
of the banana fiber modified by alkaline treatment was studied. Some important properties of this fiber changed due to some
chemical treatments, such as the crystalline fraction, dielectric behavior, metal removal (governed by solution pH) and biodegradation.
Our results showed that treated banana fiber is a low cost alternative for metal removal in aqueous industry effluents. Thus,
for regions with low resources, the biosorbents are an alternative to diminish the impact of pollution caused by local industries,
besides being a biodegradable product. 相似文献
13.
Curbani Franciane Entringer Lacerda Kaio Calmon Curbani Flávio Barreto Fernando Túlio Camilo Tadokoro Carlos Eduardo Chacaltana Julio Tomás Aquije 《Environmental Modeling and Assessment》2022,27(2):233-249
Environmental Modeling & Assessment - Subtropical estuaries such as the Vitória Island Estuarine System (VIES), located on the central coast of Brazil, are under strong anthropic pressure.... 相似文献
14.
Male-biased size dimorphism is usually expected to evolve in taxa with intense male–male competition for mates, and it is
hence associated with high variances in male mating success. Most species of pycnogonid sea spiders exhibit female-biased
size dimorphism, and are notable among arthropods for having exclusive male parental care of embryos. Relatively little, however,
is known about their natural history, breeding ecology, and mating systems. Here we first show that Ammothella biunguiculata, a small intertidal sea spider, exhibits male-biased size dimorphism. Moreover, we combine genetic parentage analysis with
quantitative measures of sexual selection to show that male body size does not appear to be under directional selection. Simulations
of random mating revealed that mate acquisition in this species is largely driven by chance factors, although actual paternity
success is likely non-randomly distributed. Finally, the opportunity for sexual selection (I
s), an indirect metric for the potential strength of sexual selection, in A. biunguiculata males was less than half of that estimated in a sea spider with female-biased size dimorphism, suggesting the direction of
size dimorphism may not be a reliable predictor of the intensity of sexual selection in this group. We highlight the suitability
of pycnogonids as model systems for addressing questions relating parental investment and sexual selection, as well as the
current lack of basic information on their natural history and breeding ecology. 相似文献
15.
Caserini Stefano Barreto Beatriz Lanfredi Caterina Cappello Giovanni Ross Morrey Dennis Grosso Mario 《Mitigation and Adaptation Strategies for Global Change》2019,24(7):1231-1248
Mitigation and Adaptation Strategies for Global Change - A new process to remove carbon dioxide (CO2) from the atmosphere, by combining commercial industrial technologies with ocean liming and CO2... 相似文献
16.
A cost-efficient way to allocate carbon dioxide (CO2) emission reductions among countries or regions is to harmonise their marginal reduction costs. This could be achieved by a market of emission reduction units (ERUs). To model such a market, we use a multi-regional MARKAL-MACRO model. It gives insights into the consequences of co-ordinating CO2 abatement on regional energy systems and economies. As a numerical application, we assess the establishment of a market of ERUs among three European countries for curbing their CO2 emissions. 相似文献
17.
Rodrigo Barreto Francesco Ferretti Joanna M. Flemming Alberto Amorim Humber Andrade Boris Worm Rosangela Lessa 《Conservation biology》2016,30(4):792-804
Approximately 25% of globally reported shark catches occur in Atlantic pelagic longline fisheries. Strong declines in shark populations have been detected in the North Atlantic, whereas in the South Atlantic the situation is less clear, although fishing effort has been increasing in this region since the late 1970s. We synthesized information on shark catch rates (based on 871,177 sharks caught on 86,492 longline sets) for the major species caught by multiple fleets in the South Atlantic between 1979 and 2011. We complied records from fishing logbooks of fishing companies, fishers, and onboard observers that were supplied to Brazilian institutions. By using exploratory data analysis and literature sources, we identified 3 phases of exploitation in these data (Supporting Information). From 1979 to 1997 (phase A), 5 fleets (40 vessels) fished mainly for tunas. From 1998 to 2008 (phase B), 20 fleets (100 vessels) fished for tunas, swordfishes, and sharks. From 2008 to 2011 (phase C), 3 fleets (30 vessels) fished for multiple species, but restrictive measures were implemented. We used generalized linear models to standardize catch rates and identify trends in each of these phases. Shark catch rates increased from 1979 to 1997, when fishing effort was low, decreased from 1998 to 2008, when fishing effort increased substantially, and remained stable or increased from 2008 to 2011, when fishing effort was again low. Our results indicate that most shark populations affected by longlines in the South Atlantic are currently depleted, but these populations may recover if fishing effort is reduced accordingly. In this context, it is problematic that comprehensive data collection, monitoring, and management of these fisheries ceased after 2012. Concurrently with the fact that Brazil is newly identified by FAO among the largest (and in fastest expansion) shark sub‐products consumer market worldwide. 相似文献
18.
Fish as indicators of disturbance in streams used for snorkeling activities in a tourist region 总被引:1,自引:0,他引:1
A set of metrics that reflect various aspects of population and fish community structure in streams used for snorkeling was
evaluated in the tourist region of Bodoquena Plateau, Brazil, with the purpose of biomonitoring the impacts of such activities.
Observations were made while snorkeling in two sites (active = with tourism; inactive = without tourism) and along the gradient
of daily tourist activity (before, during and after the passage of tourists) in two streams. Five metrics discriminated active
from inactive sites: (i) the abundance of Crenicichla lepidota and (ii) the incidence of reproductive activity in Crenicichla lepidota which were greater in inactive sites, regardless the gradient of daily tourist activity; (iii) the feeding pattern of Prochilodus lineatus, which differed among sites and along the gradient of daily tourist activity; (iv) the abundance of Moenkhausia bonita, which was higher in the active sites and significantly increased along the gradient of daily tourist activity in one stream
but decrease along the gradient in other stream; (v) the abundance of Hyphessobrycon eques, which was greater in inactive sites, regardless the gradient of daily tourist activity. With the exception of metric “iv”,
the metrics were mediated by the reduction in habitat structural complexity due to snorkeling disturbance. The definition
of these metrics is relevant because the degradation of ecosystem structural elements is one of the main impacts of recreational
activities on aquatic environments. The easy recognition of target species and high water transparency throughout the year
ensures the feasibility of these metrics in monitoring programs and may be applied by technicians after quick guides and training. 相似文献
19.
Combining policy instruments for sustainable energy systems: An assessment with the GMM model 总被引:1,自引:0,他引:1
Peter Rafaj Leonardo Barreto Socrates Kypreos 《Environmental Modeling and Assessment》2006,11(4):277-295
An assessment of the impact of an illustrative portfolio of policy instruments that address different sustainability concerns in the global energy system in areas of climate change, air pollution and introduction of renewable-energy resources is conducted. The effects of a policy set containing three instruments, implemented either individually or in combination, were examined. The policy instruments under examination in this work include: Cap-and-Trade policies imposing a CO2 emission reduction target on the global energy system, a renewable portfolio standard that forces a minimum share of renewable electricity generation, and the internalisation of external costs of power generation associated with local pollution. Implementation of these policy instruments significantly changes the structure and environmental performance of the energy sector, and particularly the structure of the electric-generation sector. The positive effects are amplified when the policy instruments are simultaneously applied, illustrating the potential for synergies between these energy-policy domains. The analysis has been conducted with the multi-regional, energy-system Global MARKAL Model (GMM), a “bottom-up” partial-equilibrium model that provides a detailed representation of energy technologies and endogenizes technology learning.
★A preliminary version of this paper has been presented at the 6th IAEE European Energy Conference on “Modelling in Energy Economics and Policy”, 1–3 September 2004, ETH Zürich, Switzerland. 相似文献
20.