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11.
Alfredo Manuel Bermúdez José María Fernández-Palacios Juana María González-Mancebo Jairo Patiño José Ramón Arévalo Rüdiger Otto Juan Domingo Delgado 《Annals of Forest Science》2007,64(1):109-119
We analyzed a post-clearcut chronosequence (0.5 to 60 years after harvesting) in the laurel forest of La Palma island (Canarian Archipelago) to determine the recovery of the stands with respect to species composition, richness, life strategies and structural parameters of the canopy. Multivariate analysis showed that exotic species, as well as annual ruderal species were confined to early-successional stages, while native perennials, typical of laurel forests, dominated the late-successional stages. Total species richness decreased significantly with time after clear-cutting. The relative fast recovery of understory native species may be due to low forest floor disturbance during harvesting. Shade-intolerant pioneer, pioneer-remnant and shade-tolerant late-successional species were the main life strategies of native tree species. Most structural parameters showed a continuous and monotonic increase (basal area, biomass) or decrease (density, percentage of photosynthetic biomass) during succession. Once clear-cutting, here performed with an interval of 8 years, is abandoned, the recovery of the laurel forest seems possible due to careful logging that protects the soil and a rapid asexual regeneration of native tree species, revealing this to be a sustainable management practice. 相似文献
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Valentina Perdomo-Cárdenas Catalina Patiño-Holguín Juan Fernando Vélez-García 《Anatomia, histologia, embryologia》2021,50(3):520-533
The kinkajou (Potos flavus) and crab-eating raccoon (Procyon cancrivorus) are carnivores belonging to the family Procyonidae, but both species are characterized by different types of locomotion. Differences can be found in the adaptations that these two species present in the forearm muscles, such as the flexor digitorum superficialis (FDS), palmaris longus (PL) and interflexorii (IF), which have been described confusingly in previous studies. Therefore, the aim of this study was to describe these muscles in both species together with their innervations to carry out an evolutionary and terminological analysis among carnivorans. Both thoracic limbs were dissected from five P. flavus and three P. cancrivorus that had died of natural causes in Wildlife Care Centers. Two PL muscles (m. palmaris longus lateralis, PLL, and m. palmaris longus medialis, PLM) were found in P. flavus, and the IF were the only superficial flexors of the digits, whereas P. cancrivorus presented the IF and two bellies homologous to the two PLs of P. flavus, where the homologous belly of the PLM sent tendons to digits II–IV. Therefore, it was considered as the FDS due to its similarity to other carnivorans, and the lateral belly is the only PL present in P. cancrivorus. The topology, attachments and innervation of these muscles in P. flavus and P. cancrivorus allowed homologies to be established, hypothesizing their evolutionary derivation from the FDS. It also allowed the differences among PL, FDS and IF muscles to be described, concluding that most carnivorans do not have a PL. 相似文献
13.
Cardinali A Pati S Minervini F D'Antuono I Linsalata V Lattanzio V 《Journal of agricultural and food chemistry》2012,60(7):1822-1829
Olive oil processing industries generate substantial quantities of phenolic-rich byproducts, which could be valuable natural sources of antioxidants. This work is focused on the recovery and structural characterization of antioxidant compounds from olive mill wastewater (OMWW), a polluting byproduct of the olive oil production process. Phenolics were extracted from the waste material using a membrane technology coupled to low-pressure gel filtration chromatography on a Sephadex LH-20. The LH-20 fraction was, in turn, characterized for its phenolic composition by HPLC-DAD-MS/MS analyses. Verbascoside, isoverbascoside, β-hydroxyverbascoside, β-hydroxyisoverbascoside, and various oxidized phenolics were identified. Uptake of verbascoside, purified from the LH-20 fraction, by HT-29 cells, an established model system for studying drug transport properties, was also assayed. Finally, the antioxidant activities of the LH-20 fraction and verbascoside were characterized by two different techniques. Individual verbascoside was more active as a scavenger of reactive oxygen species and as a chemopreventive agent protecting low-density lipoproteins from oxidative damage than the LH-20 fraction. 相似文献
14.
Effects of stocking density on intermediate culture of the razor clam Ensis arcuatus (Pharidae: Bivalvia) 下载免费PDF全文
Fiz da Costa Berta Barreiro Justa Ojea Susana Nóvoa Dorotea Martínez‐Patiño 《Aquaculture Research》2015,46(8):1858-1865
Commercial production of most bivalve species involves a phase of intermediate cultivation during which juveniles are grown under protected conditions until they can be transferred to the final grow‐out location. Consequently, the aim of this study was investigating the effect of density on growth and survival in the intermediate culture of the razor clam Ensis arcuatus in raft. Two series of experiments were performed, using in the first experiment two holding systems: 5‐L plastic bottles and PVC cylinders, both perforated, covered with a 1 mm mesh net to prevent razor clam escape and a 10‐cm layer of coarse grained sand (300–1200 μm grain diameter). In this trial, two stocking densities were tested: 0.15 and 0.30 kg m?2. In the second one‐two densities were essayed (0.62 and 1.24 kg m?2) in the PCV cylinders. In the first experiment after 27 of trial higher growth in cylinders at low density was observed. At the end of this trial all juveniles died in the 5‐L plastic bottles and higher growth and survival were recorded in the cylinders at low density. In the second experiment, significant differences in growth and survival were found on day 70, with the best results at low density. Five‐L plastic bottles must be rejected as holding system for the intermediate culture of E. arcuatus and the PVC cylinders at low densities could be a good alternative. At the end of the experiment razor clams reached the adequate size for their transfer into the grow‐out system. 相似文献
15.
Rapid climate change has the potential to alter the location of bioclimatic envelopes for a significant portion of the world’s flora. Plant species will respond variously via phenotypic plasticity, evolutionary adaptation, migration, or extinction. When fragmentation limits migration potential of many species or when natural migration rates are outstripped by the pace of climate change, some propose purposeful, human-mediated migration (assisted migration) as a solution. Here, we join the debate on assisted migration, and while recognizing the potential negative impacts, present a strategy to collect and bank seeds of plant species at risk of extinction in the face of rapid climate change to ensure that emerging habitats are as species-diverse as possible. We outline the framework currently being used by the Dixon National Tallgrass Prairie Seed Bank to prioritize species for seed banking, both for restoration purposes and for potential assisted migration in the future. We propose a strategy for collecting across the entirety of a species range, while targeting populations likely to go extinct under climate change, determined by application of species distribution models. Finally, we discuss current international efforts to collect and bank the global flora, as well as the research needs necessary to fully undertake the strategy presented. 相似文献
16.
C. Lamacchia A. Di Luccia A. Baiano G. Gambacorta B. la Gatta S. Pati Ennio La Notte 《Journal of Cereal Science》2007
Spaghetti produced in a pilot plant was dried using three different drying conditions: 60 °C for 7.5 h; 75 °C for 5.5 h; 90 °C for 5 h. Proteins of spaghetti were characterized by size-exclusion chromatography (SEC) and size-exclusion–high-performance liquid chromatography (SE-HPLC). As the temperature of the drying cycles increased, a progressive decrease of the small and large monomeric proteins and an increase in molecular size of the large polymeric proteins (LPPs) were observed. Drying temperature at 60 °C already induces a significant increase in the molecular size of the LPPs and a significant decrease of the other protein fractions. At 70 and 90 °C, large and small monomeric proteins as well as LPPs polymerized as seen by a progressive shift towards higher molecular weights in the SEC profile as temperature increased. The changes in the chromatographic profiles were accompanied by increasing amount of total unextractable polymeric protein (UPP). A decrease in stickiness and an increase in firmness corresponded to the formation of large and insoluble protein aggregates. 相似文献
17.
Messaoudi I Guevara Patiño JA Dyall R LeMaoult J Nikolich-Zugich J 《Science (New York, N.Y.)》2002,298(5599):1797-1800
Major histocompatibility complex (mhc)-encoded molecules govern immune responses by presenting antigenic peptides to T cells. The extensive polymorphism of genes encoding these molecules is believed to enhance immune defense by broadening the array of antigenic peptides available for T cell recognition, but direct evidence supporting the importance of this mechanism in combating pathogens is limited. Here we link mhc polymorphism-driven diversification of the cytotoxic T lymphocyte (CTL) repertoire to the generation of high-avidity, protective antiviral T cells and to superior antiviral defense. Thus, much of the beneficial effect of the mhc polymorphism in immune defense may be due to its critical influence on the properties of the selected CTL repertoire. 相似文献
18.
Numerous studies with teleosts have addressed the regulation and mechanisms of oocyte maturation, but largely at the exclusion of ovulation. A smaller but still considerable number of studies have focused on ovulation, and ignored maturation. Consequently, little is known about the mechanistic linkages between these two events. New information is presented here indicating that luteinizing hormone regulates the acquisition not only of oocyte maturational competence, but also ovulatory competence. The thesis is presented that maturation and ovulation are closely integrated and overlapping events that are best viewed conceptually and experimentally as parts of a functional whole. 相似文献
19.
Ovarian follicle growth, maturation, and ovulation in teleost fish 总被引:12,自引:0,他引:12
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