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111.
Summary. The aggressiveness of the house spider (Tegenaria atrica) has a chemical basis in terms of intra- and interspecific chemical communication. Vibrations are used for longer range detection of intruders on the web territory whereas cuticular lipids mediate shorter range agonistic behaviors. Two cuticular acids were shown to promote aggressive responses from adult spiders, whereas mixtures of cuticular alkanes acted as inhibition signals. 相似文献
112.
This paper makes a distinction between three theoretical frameworks that have been highly influential in the discourse on innovation, competitiveness and sustainability: sectoral systems of innovation (SSI), technological innovation systems (TIS) and socio-technical systems (ST-Systems). These frameworks share a common systems approach to innovation but are often positioned as different bodies of literature that correspond to different epistemic communities. This paper is explorative and conceptual in nature. It presents a systematic comparative review of SSI, TIS and ST-Systems based on the following analytical dimensions: (1) system boundaries, (2) actors and networks, (3) institutions, (4) knowledge, (5) dynamics and (6) policy approach. In the concluding section commonalities and differences, of the three approaches, are presented and suggestions for complimentarily are made. 相似文献
113.
Roberto Schaeffer Alexandre Salem Szklo Fernando Monteiro Cima Giovani Machado 《Natural resources forum》2005,29(4):284-297
This article summarizes the results of the project on indicators for sustainable energy development (ISED) in Brazil. The project's aim was to present energy related economic, social and environmental data to policy makers in a coherent and consistent form, showing interlinkages, time‐series and cross‐sectoral analyses and assess energy policy. Two priority areas assessed by these indicators, regarding the country's energy supply and demand, helped in the identification of a number of energy policy options that focused on specific aspects of the country's energy sector. On the supply side, these options include the development and stimulation of renewable energy, such as small‐scale hydroelectric, wind, solar photovoltaic power and bagasse cogeneration; stimulation of programmes for ethanol use as automotive fuel and sugarcane bagasse cogeneration; and implementation of natural gas‐fired, combined heat and power (CHP) plants. On the demand side, policy options include: the full implementation of the law on efficiency standards for appliances; expansion of utility investment in end‐use energy efficiency; adoption of targets and protocols to reduce energy intensity in the industrial sector; improvement of passenger transport efficiency; and the creation of a fund to improve energy affordability for the poor. 相似文献
114.
The clearing of forests to obtain land for pasture and agriculture and the replacement of autochthonous species by other faster-growing varieties of trees for timber have both led to the loss of vast areas of forest worldwide. At present, many developed countries are attempting to reverse these effects, establishing policies for the restoration of older woodland systems. Reforestation is a complex matter, planned and carried out by experts who need objective information regarding the type of forest that can be sustained in each area. This information is obtained by drawing up feasibility models constructed using statistical methods that make use of the information provided by morphological and environmental variables (height, gradient, rainfall, etc.) that partially condition the presence or absence of a specific kind of forestation in an area. The aim of this work is to construct a set of feasibility models for woodland located in the basin of the River Liébana (NW Spain), to serve as a support tool for the experts entrusted with carrying out the reforestation project. The techniques used are multilayer perceptron neural networks and support vector machines. Their results will be compared to the results obtained by traditional techniques (such as discriminant analysis and logistic regression) by measuring the degree of fit between each model and the existing distribution of woodlands. The interpretation and problems of the feasibility models are commented on in the Discussion section. 相似文献
115.
Rodríguez-Aguilar Maribel Díaz de León-Martínez Lorena García-Luna Sofía Gómez-Gómez Alejandro González-Palomo Ana Karen Pérez-Vázquez Francisco Javier Díaz-Barriga Fernando Trujillo Joyce Flores-Ramírez Rogelio 《Environmental science and pollution research international》2019,26(25):25825-25833
Environmental Science and Pollution Research - Indoor air pollution is an important risk factor for the generation of lung diseases in developing countries. The indigenous population is... 相似文献
116.
Puche Regaliza Julio César Alvear González Arturo Aparicio Castillo Santiago Arranz Val Pablo Lara Ortega Fernando 《Journal of Material Cycles and Waste Management》2018,20(3):1842-1856
Journal of Material Cycles and Waste Management - Levels of public satisfaction among the inhabitants of Burgos with their urban waste collection service are analyzed by comparing satisfaction... 相似文献
117.
Dilermando Pereira Lima Junior André Lincoln Barroso Magalhães Fernando Mayer Pelicice Jean Ricardo Simões Vitule Valter M. Azevedo-Santos Mário Luís Orsi Daniel Simberloff Angelo Antônio Agostinho 《Ambio》2018,47(4):427-440
The Convention on Biological Diversity proposed the Aichi Biodiversity Targets to improve conservation policies and to balance economic development, social welfare, and the maintenance of biodiversity/ecosystem services. Brazil is a signatory of the Aichi Biodiversity Targets and is the most diverse country in terms of freshwater fish, but its national policies have supported the development of unsustainable commercial and ornamental aquaculture, which has led to serious disturbances to inland ecosystems and natural resources. We analyzed the development of Brazilian aquaculture to show how current aquaculture expansion conflicts with all 20 Aichi Targets. This case suggests that Brazil and many other megadiverse developing countries will not meet international conservation targets, stressing the need for new strategies, such as the environmental management system, to improve biodiversity conservation. 相似文献
118.
Long-term effects of lead poisoning on bone mineralization in vultures exposed to ammunition sources
Gangoso L Alvarez-Lloret P Rodríguez-Navarro AA Mateo R Hiraldo F Donázar JA 《Environmental pollution (Barking, Essex : 1987)》2009,157(2):569-574
Long-lived species are particularly susceptible to bioaccumulation of lead in bone tissues. In this paper we gain insights into the sublethal effects of lead contamination on Egyptian vultures (Neophron percnopterus). Our approach was done on the comparison of two populations (Canary Islands and Iberian Peninsula) differing in exposures to the ingestion of lead ammunition. Blood lead levels were higher in the island population (Canary Islands range: 5.10-1780 μg L−1n = 137; Iberian Peninsula range: 5.60-217.30 μg L−1n = 32) showing clear seasonal trends, peaking during the hunting season. Moreover, males were more susceptible to lead accumulation than females. Bone lead concentration increased with age, reflecting a bioaccumulation effect. The bone composition was significatively altered by this contaminant: the mineralization degree decreased as lead concentration levels increased. These results demonstrate the existence of long-term effects of lead poisoning, which may be of importance in the declines of threatened populations of long-lived species exposed to this contaminant. 相似文献
119.
Luciane Almeri Tabaldi Denise Cargnelutti Jamile Fabbrin Gonalves Luciane Belmonte Pereira Gabriel Y Castro Joseila Maldaner Renata Rauber Liana Vernica Rossato Dilson Antnio Bisognin Maria Rosa Chitolina Schetinger Fernando Teixeira Nicoloso 《Chemosphere》2009,76(10):1402-1409
The objective of this study was to evaluate whether the oxidative stress caused by aluminum (Al) toxicity is an early symptom that can trigger root growth inhibition in Macaca (Al-sensitive) and SMIC148-A (Al-tolerant) potato clones. Plantlets were grown in a nutrient solution (pH 4.00) with 0, 100 and 200 mg Al L−1. At 24, 72, 120 and 168 h after Al addition, root length and biochemical parameters were determined. Regardless of exposure time, root length of the Macaca clone was significantly lower at 200 mg Al L−1. For the SMIC148-A clone, root length did not decrease with any Al treatments. Al supply caused lipid peroxidation only in Macaca, in both roots (at 24, 72, 120 and 168 h) and shoot (at 120 and 168 h). In roots of the Macaca, catalase (CAT) and ascorbate peroxidase (APX) activity decreased at 72 and 120 h, and at 24, 72 and 120 h, respectively. At 168 h, both activities increased upon addition of Al. In roots of the SMIC148-A, CAT activity increased at 72 and 168 h, whereas APX activity decreased at 72 h and increased at 24, 12 and 168 h. The Macaca showed lower root non-protein thiol group (NPSH) concentration at 200 mg Al L−1 in all evaluations, but the SMIC148-A either did not demonstrate any alterations at 24 and 72 h or presented higher levels at 120 h. This pattern was also observed in root ascorbic acid (AsA) concentration at 24 and 120 h. The cellular redox status of these potato clones seems to be affected by Al. Therefore, oxidative stress may be an important mechanism for Al toxicity, mainly in the Al-sensitive Macaca clone. 相似文献
120.
Patrizia D''Ettorre Christine Errard Fernando Ibarra Wittko Francke Abraham Hefetz 《Chemoecology》2000,10(3):135-142
Summary. The dulotic queen ant, Polyergus rufescens, must first penetrate a host colony and kill the resident queen in order to successfully founding a new colony. Successful
usurpation by a newly mated queen predictably depends on a dual strategy. Although, it can sneak in by being “chemically insignificant”
with respect to cuticular hydrocarbons, it may also need to deter prospective host-worker aggressors. Chemical analysis of
Dufour's gland secretion of P. rufescens queens and workers by GS/MS revealed that queen secretion is typified by esters of butanoic acid and acetic acid, of which
decyl butanoate comprises over 80%. Butanoates and acetates are also present in the workers' secretion, but these are of higher
molecular weight, and octadecyl butanoate represents the major compound. Using synthetic mixtures of queen and worker Dufour's
gland, we tested the hypothesis that these secretions modify the aggressive behavior of the host species Formica cunicularia>. The queen-like synthetic mixture significantly reduced aggression of the host workers towards alien conspecifics, but neither
pentane nor the worker-like synthetic mixture showed this effect. Although Dufour's gland content of >Polyergus queens was suggested to function as an appeasement pheromone (Topoff et al. 1988; Mori et al. 2000), we hypothesized that it may in fact act as a repellent. In order to test this hypothesis we exposed starved F. cunicularia workers to a droplet of honey on a glass slide applied with one of the following compounds: decyl butanoate (queen major
compound), octadecyl butanoate (worker main compound), limonene (a reported ant repellent), and pentane (solvent control).
Of these, the workers were repelled only by the decyl butanoate and did not approach the honey. We conclude that during usurpation
the queen actively repels aggressive workers by emitting Dufour's gland repellent, comprising the alternative tactic in the
usurpation dual strategy. This represents another chemical weapon in the diverse arsenal used by parasites to overcome the
host's resistance.
Received 7 April 2000; accepted 17 May 2000 相似文献