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131.
Adriano Evandir Marchello Daniela Mariano Barreto Ana Teresa Lombardi 《Water, air, and soil pollution》2018,229(2):48
The products that employ nanoparticles (NPs) in their composition have increased since the beginning of NP production; hence, their availability in the environment, especially in aquatic ecosystems, tends to increase. In these ecosystems, the phytoplankton is immersed in a complex matrix of nutrients, excreted materials, and other chemical compounds, which can influence the metabolic strategy of microalgae. One of the metabolic ways is mixotrophy, a situation whereby microalgae perform photosynthesis and use dissolved organic carbon at the same time. Most toxicity evaluations do not consider such a metabolic route, but this can represent a preferential metabolism in natural environments. The present study aimed at evaluating the effects of NP-TiO2 at a log concentration range of ??3.10 to 0.89, on photosynthesis, growth, viability, and biochemical composition of the microalgae Chlorella sorokiniana during photoautotrophic and mixotrophic growth (glucose as the organic carbon source). The results showed lower chlorophyll a and photosynthetic activity in mixotrophy than in photoautotrophy, which can be due to a decreased need for photosynthesis in mixotrophy. Photoautotrophy cultures were sensitive to NPs, reaching 39% of viability at log 0.89, while in mixotrophy, cell viability was not affected by NPs. The biochemical composition and cell density changed as a function of NP concentrations, with increase in the protein/carbohydrate ratio in both treatments. The results showed that C. sorokiniana is more resistant to NPs during mixotrophic growth, but with changes in biochemical composition, whereas the photoautotrophic cultures were more sensitive to the increase in NP concentrations. 相似文献
132.
Armin M Stroebel Matthias Bergner Udo Reulbach Teresa Biermann Teja W Groemer Ingo Klein Johannes Kornhuber 《Journal of circadian rhythms》2010,8(1):10
Background
Animals, including humans, exhibit a variety of biological rhythms. This article describes a method for the detection and simultaneous comparison of multiple nycthemeral rhythms. 相似文献133.
Isabel Egea Paloma Sánchez-Bel Felix Romojaro Maria Teresa Pretel 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):121-129
Total antioxidant activity of six non-cultivated but traditionally collected fruits from the south of Europe was assessed
by measuring their ability to reduce the hydroxyl radical ( OH· ) \left( {{\hbox{O}}{{\hbox{H}}^\bullet }} \right) and hydrogen peroxide (H2O2), and their Trolox equivalent antioxidant capacity (TEAC). This antioxidant activity was compared with that shown by the
synthetic antioxidants BHA (E-320), BHT (E-321) and propyl gallate (E-310). Total phenolics, ascorbic acid and the carotenoid
content of the fruits were also analyzed. All fruits showed a high ability to scavenge the OH· {\hbox{O}}{{\hbox{H}}^\bullet } radical, ranging from 60.61% to 81.04% inhibition for Rosa canina and Crataegus monogyna, respectively. The H2O2 scavenging capacity and the TEAC value varied widely, ranging between 3.63% and 87.26% inhibition of H2O2 and between 0.47 and 416.64 mM trolox g−1 FW for Sorbus domestica and Rosa canina, respectively. The antioxidant activity of fruits was higher than that of the synthetic additives analyzed, except in the
TEAC assay. The phenolic and carotenoid content of R. canina was much higher than that of the other fruits analyzed and its ascorbic acid concentration was also high, reflecting its
higher efficacy towards ABTS ·- {\hbox{ABT}}{{\hbox{S}}^{ \bullet - }} (TEAC assay) and H2O2 species. In spite of these associations, the correlation coefficients between total antioxidant activity and the antioxidant compounds
analyzed were not very significant; only phenolics and carotenoids showed a marginal correlation with the TEAC assay. The
results support the possible use of R. canina as natural antioxidant to replace the synthetic additives, as well as their use in the production of functional foods with
a high antioxidant activity. 相似文献
134.
Maria Teresa Scicluna Andrea CaprioliGiorgio Saralli Giuseppe MannaAntonino Barone Antonella CersiniGiusy Cardeti Renato Ugo CondoleoGian Luca Autorino 《Veterinary microbiology》2010
Only limited information is available on the epidemiology and pathogenesis of Bovine Herpesvirus 1 (BoHV-1) in domestic buffalos. In this study, a virulent BoHV-1 field strain isolated from cattle was inoculated into buffaloes to evaluate their susceptibility to the virus and to investigate the establishment of viral latency through clinical, virological and serological investigations. Latency was also studied by attempting viral reactivation using pharmacological induction. Six of seven male, 5 months old buffaloes were intranasally inoculated with BoHV-1; the other animal was kept as negative control. The animals were clinically monitored during the post-infection (P.I.) and the post-pharmacological induction (P.P.) periods. During these periods, nasal and rectal swabs, and blood samples, with and without anticoagulant, were collected at 2–3 day intervals. On culling the animals, 206 days P.I., their trigeminal ganglia and tonsils were collected. No clinical signs referable to BoHV-1 were observed throughout the experimental period. However, seropositivity was detected in all infected animals within day 20 P.I., using BoHV-1 glycoprotein E and glycoprotein B competitive ELISAs (IDEXX) and virus neutralisation test. In real-time PCR (RT-PCR), five of these animals were positive, at least once, for nasal or rectal swabs, during the P.I. period. The sixth infected animal was found positive only in the trigeminal ganglia after culling. Ganglia were also positive for two other animals. Virus isolation in permissive cell-lines was successful for a part of the RT-PCR positive samples. The detected viruses were confirmed by genetic analysis as identical to the inoculated strain. No evidence of infection was observed in the negative control. This study represents the first experimental transmission of BoHV-1 in buffaloes, confirming their susceptibility to infection and their possible role as host/reservoirs of BoHV-1. 相似文献
135.
Teresa A. Newsome Jean L. Heineman Amanda F. Linnell Nemec Philip G. Comeau André Arsenault Michaela Waterhouse 《Forest Ecology and Management》2010
We investigated survival and growth responses of planted and advance natural regeneration species of varying shade tolerance to partial retention harvesting in moist warm Interior Cedar-Hemlock (ICHmw2) and dry cool Montane Spruce (MSdk) ecosystems of southeastern British Columbia, Canada. Treatments included three levels of overstory basal area retention (none, light (∼25%), or heavy (∼50%)) installed by two harvest methods (handfelled or a pushover falling technique being tested for its ability to control the spread of root disease). After 10 years, growth of both planted and natural regeneration species of varying shade tolerance tended to increase with decreasing overstory retention and associated increases in light availability. In contrast, significant survival responses to retention level were lacking except in the case of shade-intolerant western larch. Harvest method had a variable effect on regeneration survival and growth. Where significant responses did occur, they were generally attributed to harvesting effects on the characteristics of planting microsites rather than root disease spread. Natural regeneration densities at the ICHmw2 site were high at all retention levels, whereas stocking was less consistent at the MSdk site. We concluded that moderately shade-tolerant to shade-tolerant interior spruce and western redcedar can, under conditions similar to those of our study sites, be successfully established under overstories of up to approximately 25 m2/ha basal area, but that growth performance is likely to be significantly lower than in clearcuts. Despite early survival issues, conclusions regarding Douglas-fir were similar. Poorer survival and vigour of shade-intolerant western larch suggested this species is not suitable for regeneration in partial retention systems where timber production is the primary objective. Where non-timber objectives predominate, survival and acceptable growth of even a small proportion of larch could add to the diversity of the regenerating stand. 相似文献
136.
Laura Martín María Teresa Martín 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(2):343-361
Esca and Petri disease, caused by Phaeoa-cremonium, and other grapevine decline diseases, such as eutypa dieback, are responsible for serious economic losses to the wine industry worldwide. In the present work, 175 isolates of Phaeoacremonium spp. were collected (mostly in the region of Castilla y León, Spain) from vines either asymptomatic or symptomatic for grapevine decline diseases. The sequences of DNA fragments of 30 isolates were analysed. Amplicons of ITS, and partial gene of the β-tubulin, actin, calmodulin and translation elongation factor 1-α [EF1-α], were obtained by PCR. This is the first time that any exon of the EF1-α gene or exons 6–7 of the β-tubulin gene of seven Phaeoacremonium spp. have been amplified. Amplicons of the calmodulin and EF1-α exons were the most informative in terms of species differentiation: only 52.6 % and 56.6 % similarity across six and seven species was respectively seen. Phylogenetic analysis of combined DNA sequences revealed five Phaeoacremonium species isolated from the sampled plants; P. aleophilum was the most common. Four other species were found, however only one isolate each. P. mortoniae and P. iranianum are here reported for the first time on grapevines in the region of Castilla y León and the neighbouring region of La Rioja respectively. In total, 29 nucleotide differences among the studied gene fragments were seen across 23 isolates of P. aleophilum. Network analysis showed these Spanish P. aleophilum isolates to fall into two main groups of genotypes. P. aleophilum genotypes belonging to group 1 were mostly isolated from young grapevines affected by Petri disease but genotypes included in group 2 were isolated from adult plants showing esca or eutypa dieback symptoms. 相似文献
137.
Rafaella de Paula Paseto Femandest Maria Teresa de Alvarenga Freire Celso da Costa Carrer Marco Antonio Trindade 《农业科学学报》2013,12(11):1946-1952
Nowadays, lamb meat represents only 7% of all meat produced in the world. In recent years the demand for standardized lamb meat cuts has been considered of great importance and the marketing occurs predominantly in the form of frozen cuts. Herewith, the main of this work was to evaluate the stability and safety of lamb meat during frozen storage. Meats were vacuum packed in high barrier multilayer plastic iflms and stored during 12 mon at (-18±1)℃. The meat stability was assessed by physical and chemical (lipid oxidation, objective color, pH value, cooking losses and instrumental texture), microbiological (total count of psychrotrophic, coliform count at 45℃, coagulase-positive staphylococci and the presence of Salmonella) and sensory analysis (acceptance test and visual evaluation). The vacuum packed lamb meat remained stable as to most physical and chemical indexes. Microbiological indexes showed good stability throughout the storage period according to Brazilian legislation standards to pathogenic microorganisms. Although a signiifcant reduction in tenderness (shear force increase from 3 to 8 kg), it showed a good sensorial acceptance for all attributes tested, including texture, with scores of around 7 (like moderately) during the 12 mon of storage. Therefore, it can be concluded that, under the conditions applied in this study, lamb meat presents a shelf life of at least 12 mon when stored at-18℃. 相似文献
138.
OssamA Kodad Gloria Estopañan Teresa Juan Francisco Molino Ali Mamouni Zerhoun Messaoudi 《The Journal of Horticultural Science and Biotechnology》2013,88(5):381-386
SummaryOil contents and fatty acid compositions were determined in 17 almond cultivars growing under two different Mediterranean conditions, in northeast Spain and in central Morocco. The major differences were irrigation management in Spain and higher temperatures in Morocco. Although a cultivar effect was observed for some compounds, the general trend was for an increase in total oil content [58.65% vs. 55.58% (w/w)] and in the percentage of oleic acid [71.1% vs. 68.62% (w/w)] in those kernels harvested in Spain, probably due to having lower temperatures and better water status. As the total oil content and level of oleic acid in almond oil are the major parameters for higher quality almond kernels, these results emphasise the need to optimise the management of almond orchards to improve kernel quality, not only from the commercial and industrial points of view, but also because of their healthgiving properties. 相似文献
139.
García-Estévez I Escribano-Bailón MT Rivas-Gonzalo JC Alcalde-Eon C 《Journal of agricultural and food chemistry》2012,60(6):1373-1379
Detection and individual quantification of oak wood ellagitannins in oak barrel aged red wine samples are difficult mainly due to their low levels and the similarity between their structures. In this work, a quantification method using mass spectrometry has been developed and validated to quantify wine ellagitannins after sample fractionation with a previously reported method. The use of an internal standard is a requirement to correct mass signal variability. (-)-Gallocatechin, among the different tested compounds, was the only one that proved to be a suitable internal standard making possible the accurate and individual quantification of the main oak wood ellagitannins. The developed methodology has been used to detect and quantify these ellagitannins in different Spanish commercial wines, proving its usefulness. 相似文献