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91.
Óscar Alfranca Luis Diaz-Balteiro A. Casimiro Herruzo 《Forest Policy and Economics》2009,11(3):161-168
This paper uses a logit model to quantify the probability of generating technological innovations in a representative sample of firms belonging to the wood-based industry in Spain (lumber and wood products, pulp and paper, and wooden furniture). Special attention has been paid to the incidence of environmental and quality strategies in firms as being determinant factors of innovation. Econometric results have indicated that these two strategies have increased innovation generation in the wood-based industry. In general, environmental and quality strategies tend to exert positive effects on the specific innovation activities of firms, in spite of the fact that a substitution relationship was found between the existence of quality management systems and R&D subsidies. 相似文献
92.
Sarah Giovanna Montenegro Lima Marjorie Caroline Liberato Cavalcanti Freire Vernica da Silva Oliveira Carlo Solisio Attilio Converti dley Antonini Neves de Lima 《Marine drugs》2021,19(9)
Astaxanthin (AST) is a biomolecule known for its powerful antioxidant effect, which is considered of great importance in biochemical research and has great potential for application in cosmetics, as well as food products that are beneficial to human health and medicines. Unfortunately, its poor solubility in water, chemical instability, and low oral bioavailability make its applications in the cosmetic and pharmaceutical field a major challenge for the development of new products. To favor the search for alternatives to enhance and make possible the use of AST in formulations, this article aimed to review the scientific data on its application in delivery systems. The search was made in databases without time restriction, using keywords such as astaxanthin, delivery systems, skin, cosmetic, topical, and dermal. All delivery systems found, such as liposomes, particulate systems, inclusion complexes, emulsions, and films, presented peculiar advantages able to enhance AST properties, among which are stability, antioxidant potential, biological activities, and drug release. This survey showed that further studies are needed for the industrial development of new AST-containing cosmetics and topical formulations. 相似文献
93.
Would behavioral thermoregulation enable pregnant viviparous tropical lizards to cope with a warmer world? 下载免费PDF全文
Saúl LÓPEZ‐ALCAIDE Miguel NAKAMURA Eric N. SMITH Enrique MARTÍNEZ‐MEYER 《Integrative zoology》2017,12(5):379-395
Sceloporus lizards depend on external heat to achieve their preferred temperature (Tsel) for performing physiological processes. Evidence both in the field and laboratory indicates that pregnant females of this Genus select body temperatures (Tb) lower than 34 °C as higher temperatures may be lethal to embryos. Therefore, thermoregulation is crucial for successful embryo development. Given the increase in global air temperature, it is expected that the first compensatory response of species that inhabit tropical climates will be behavioral thermoregulation. We tested whether viviparous Sceloporus formosus group lizards in the wild exhibited differences in thermoregulatory behavior to achieve the known Tsel for developing embryos regardless of local thermal conditions. We quantified field active body temperature, thermoregulatory behavior mechanisms (time of sighting, microhabitat used and basking time) and available microhabitat thermal conditions (i.e. operative temperature) for 10 lizard species during gestation, distributed along an altitudinal gradient. We applied both conventional and phylogenic analyses to explore whether Tb or behavioral thermoregulation could be regulated in response to different thermal conditions. These species showed no significant differences in field Tb during gestation regardless of local thermal conditions. In contrast, they exhibited significant differences in their behavioral thermoregulation associated with local environmental conditions. Based on these observations, the differences in thermoregulatory behavior identified are interpreted as compensatory adjustments to local thermal conditions. We conclude that these species may deal with higher temperatures predicted for the tropics by modulating their thermoregulatory behavior. 相似文献
94.
Deciphering the effects of disperser assemblages and seed mass on patterns of seed dispersal in a rodent community 下载免费PDF全文
The sizes of both seed dispersers and seeds are traits that are likely to interact to influence seed fate in many synzoochoric plant species. Here, we examined whether members of a granivorous rodent community consisting of species of different body size vary in their effectiveness as seed dispersers, and how this relationship may be altered by seed size. We marked northern red oak (Quercus rubra) acorns with plastic tags and placed them in size‐selective rodent exclosures. The exclosures allowed differential access of rodent groups based on different body size: (i) small (e.g. Peromyscus spp.); (ii) small and medium (e.g. Tamias striatus); and (iii) small, medium and large (e.g. Sciurus carolinensis) species of rodents. Acorn removal did not differ among exclosure types, but more seeds were missing when removed by small rodents, probably because of larderhoarding. The treatments did not influence the relative frequency of acorn consumption. However, small rodents cached considerably fewer and partially ate more acorns than the other 2 groups. The mean dispersal distance was the longest for cages with medium openings, intermediate for cages with large openings and the shortest for cages with small openings. Acorn mass positively affected the probability of caching and this relationship was unaffected by exclosure type. In conclusion, granivorous rodents of different body sizes strongly differed in their interactions with acorns, with small rodents acting primarily as acorn predators and medium and large species contributing significantly more to dispersal of red oaks. 相似文献
95.
Ólöf Dóra Bartels Jónsdóttir Julia Schregel Snorre B. Hagen Camilla Tobiassen Siv Grethe Aarnes Albert K. D. Imsland 《Aquaculture International》2018,26(1):49-60
The potential for genetic contamination of stocks arising from translocation and subsequent release or escape of translocated and/or genetically mixed stocks may be a significant risk to wild populations. In this context, we undertook a population genetic survey of stocks of lumpfish (Cyclopterus lumpus) along the Norwegian coast to establish the existing genetic population structure, which will aid the development of policy of the species’ use as cleaner fish in salmonid aquaculture. This was done by using 14 microsatellite loci and 287 specimens collected at five fishing grounds, covering most of the Norwegian coastline from south to north, with additional 18 samples of first-generation reared fish from a fish farm outside Tromsø (North Norway). Overall, there was no indication of significant spatial genetic structuring or of positive correlation between geographic and genetic distance among the wild lumpfish samples. These results suggest that, should translocated individuals escape from aquaculture in Norway, this will probably have little to no impact on the genetic composition of the local fish population. 相似文献
96.
João Carvalho Óscar Cardoso Mário Costa Abel Rodrigues 《European Journal of Forest Research》2017,136(1):185-192
This work presents the results of a study on the variation of the chemical composition of Pyrenean oak (Quercus pyrenaica Willd.) heartwood among different sites and its relationship with the soil chemical characteristics. The chemical characteristics of the heartwood are quantified in terms of proximate and ultimate analysis, calorific value and ash composition. Subsequently, the relationship between the wood chemical characteristics and the soil characteristics was also examined. The results showed no significant differences between the wood chemical characteristics from different sites. There are, however, significant differences between trees from the same site regarding the wood ash content, the calorific value and the contents of nitrogen and hydrogen. Strong correlations were observed between the heartwood ash contents of BaO, MnO, CuO and TiO2 and the soil nitrogen, phosphorous and potassium and the soil exchangeable base contents. 相似文献
97.
Marcus Vinicius Freire Andrade Isabel Kimiko Sakamoto Aline Gomes de Oliveira Paranhos Edson Luiz Silva Maria Bernadete Amâncio Varesche 《Water, air, and soil pollution》2017,228(4):165
Effects of ethanol and nitrate on linear alkyl benzene sulfonate (LAS) degradation were investigated using central composite design. At experimental design, removal of 99.9% was observed in batch reactors (1 L) with 9.8 to 41.2 mg L?1 of LAS. The batch reactors were kept under agitation at 120 rpm and 30 °C. Ethanol (co-substrate) and nitrate (electron acceptor) were statistically significant factors (p?<?0.05) in surfactant removal. Optimal values were 97.5 and 88 mg L?1 for ethanol and nitrate, respectively. LAS removal was kinetically investigated by varying surfactant concentration while using optimal values. Batch I (27 mg L?1 LAS) exhibited greater degradation rate (KLAS) (0.054 h?1) in the presence of ethanol and nitrate. Nonetheless, in Batch II (60 mg L?1 LAS), the KLAS values decreased in those reactors probably due to inhibition by excess substrate for same concentrations of nitrate and ethanol added in reactors. As LAS concentration increased, the dominance of bacterial populations also increased, whereas diversity index decreased from 2.8 (inoculum) to 2.4 and 2.5 for reactors with both added nitrate and ethanol and those with only added ethanol, respectively. Probably, a selection of microbial populations occurred in relation to LAS concentration. The nitrate and ethanol, at able concentration, made it possible the induction of denitrifying microrganisms foward to LAS removal. 相似文献
98.
Jailson Cavalcante Cunha Maria Betânia Galvão dos Santos Freire Hugo Alberto Ruiz Jhonatha David Guimarães Silva 《Communications in Soil Science and Plant Analysis》2017,48(1):20-36
The soil areas affected by salts have increased in recent years. Searching intensively for management and recovery strategies should help minimize these problems. Studies related to the response of halophytes to fertilization can provide important information regarding the most adequate management for phytoremediation. The aim of this study was to evaluate dry matter production and sodium extraction capacity of atriplex plants, in response to nitrogen doses, with and without phosphorus application. The experiment was carried out in a greenhouse at the Federal Rural University of Pernambuco (UFRPE), in Recife, Pernambuco, Brazil and was set up in a randomized block design, with four replicates, in a 2 × 5 factorial scheme (0 and 134 mg dm?3 of P and 0, 20, 40, 60, and 80 mg dm?3 of N). The addition of nitrogen (N) and improved sodium (Na) uptake increased Na contents by 4.1, 3.6, and 1.8 times, for P0, and by 4.0, 8.4, and 2.1, for P134, in leaves, stems, and roots, respectively. There was a decrease in Na both in the saturation-paste extract and in the exchange complex with the increase in N in soil. N supply potentiates Na extraction by Atriplex nummularia, being a feasible technique to recover saline soils through phytoremediation. 相似文献
99.
Enriching Artemia nauplii with a high DHA‐containing lipid emulsion: search for an optimal protocol 下载免费PDF全文
Elena Viciano Óscar Monroig Ana Salvador Jaume Amat Susana Fiszman Juan Carlos Navarro 《Aquaculture Research》2015,46(5):1066-1077
This study aimed to investigate practical strategies to optimize the use of a high‐docosahexaenoic acid (DHA) lipid emulsion (M70), a product with great potential in live prey enrichments for marine larviculture. Considering its particularly high content in DHA (22:6n‐3), the adequate utilization of the emulsion for Artemia enrichments was evaluated in a series of six experiments. More specifically, the bioencapsulation efficiency of M70 into Artemia nauplii was tested under different experimental conditions of oxygen source, aeration flow, incubation temperature, concentration and dosage, as well as nauplial densities. Our results showed that an optimal utilization of M70 is achieved with incubation temperatures of 28°C, moderate aeration flows and nauplial densities of 300 ind per mL. In addition, the emulsion can be dispensed in the enrichment medium in one single dose of 0.8 g L?1, with no apparent detrimental effects on its oxidative stability and Artemia nauplii survival during enrichment. 相似文献
100.
Andre Freire Cruz Lucas Fagundes Silva Tiago Vieira Sousa Alessandro Nicoli Trazilbo Jose de Paula Junior Eveline Teixeira Caixeta Laercio Zambolim 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(2):343-354
The common bean (Phaseolus vulgaris L.) is widely cultivated in Brazil and is known as a very important crop for families in this country. Fusarium wilt severely harms common beans and has become a big issue for this crop. In order to assist the breeding programs that target resistance to this disease, the evaluation of genetic diversity of the pathogen and its molecular characterization are crucial. Thus, the present goal was to identify Fusarium isolates obtained from several places in Brazil using molecular tools; select molecular markers for these isolates; and analyze their diversity. All of isolates were molecularly identified as Fusarium oxysporum f. sp. phaseoli (Fop). By using seven selected SSR markers, the results of diversity obtained by the dendrogram and the Bayesian analysis formed four groups where a large diversity of this fungus was found within each state. However, the groups were more homogenous according to the collection source and the pathogenicity test. More specifically, group 2 was composed of the most virulent strains and originated from Minas Gerais State – UFV, and group 3 was mostly composed by isolates from Goias state. Group I was also more diverse in terms of location and virulence. The overall results indicated a positive correlation between Fusarium diversity and its virulence to common bean. Furthermore, the use of these markers was effective in molecular identification and in detecting polymorphism within F. oxysporum f. sp. phaseoli. 相似文献