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1.
Abstract The way in which foraging wasps use cues for prey location and choice appears to depend on both the context and on the type of prey. Vespula germanica is an opportunistic, generalist prey forager, and individual wasp foragers often return to hunt at sites of previous hunting success. In this paper, we studied which cues are used by this wasp when relocating a food source. Particularly we analysed the response to a displaced visual cue versus a foraging location at which either honey or cat food had been previously presented. We conclude that location is used over a displaced visual cue for directing wasp hovering, although the landing response is directed differently according to bait type. When wasps are exploiting cat food, location also elicits landing, but if they are exploiting honey, a displaced visual cue elicits landing more frequently than location. 相似文献
2.
Gymnocharacinus bergi (Pisces, Characidae), an endemic fish in the headwaters of the Valcheta stream in northern Patagonia, displays a fright reaction. As this species inhabits a rapid stream, we hypothesized that the alarm reaction might be socially transmitted through visual information, because the detection of alarm pheromone would be restricted to those fish located downstream from the releaser. Alarm substances elicited a decrease in the swimming activity and a tendency to remain at the bottom of the aquarium. Individuals that observed the fright reaction, but were not exposed to the pheromone, spent significantly more time at the bottom of the aquarium imitating the alarm response, and tended to approach the others. Gregarious behaviour was observed; however, interactions (number of approaches) were stronger between those fish held prior to testing in the same aquarium; smaller fish in particular tended to get closer to bigger ones. Greater group cohesion was found between individuals that were exposed to the alarm pheromone. 相似文献
3.
Biomechanical basis of optimal scoliosis surgical correction 总被引:6,自引:0,他引:6
D N Ghista G R Viviani K Subbaraj P J Lozada T M Srinivasan G Barnes 《Journal of biomechanics》1988,21(2):77-88
For an optimal approach to surgical correction of scoliosis, it was deemed desirable to biomechanically simulate the set of corrective forces applied by alternative internal fixation systems, so as to determine and apply the internal fixation system producing the best correction under safe levels of forces applied by the fixation systems to the spinal structures. To this end, we have developed, and presented here, (1) a spinal finite-element model relating the applied corrective forces to the corrected spinal configurations, (2) a method for determining the stiffness of the patient's spine prior to surgery, (3) computerized finite-element analysis simulation of alternative internal correction-fixation systems, so as to determine the most efficacious system, (4) instrumentations for surgically implementing the recommendations of the surgical simulation analysis and (5) comparisons of the model-simulated and surgically-obtained corrected spinal configurations. These procedures together constitute the biomechanical foundations of scoliosis surgical correction. 相似文献
4.
Tannya Lozada G. H. J. de Koning Michael Kessler Alexandra-Maria Klein Teja Tscharntke 《Diversity & distributions》2008,14(1):59-68
Biodiversity patterns may be influenced by the species geographical range sizes, but this is rarely shown. We used a highly replicated and large-scale study in coastal Ecuador to determine for the first time the importance of latitudinal range size of plant species in their response to land-use activities. We examined herbaceous plant communities of five land-use types with decreasing anthropogenic disturbance (from the most intervened rice and pasture to the less intervened managed agroforest, abandoned agroforest, and forest) in a low and a high impact human-dominated landscape. All species were classified in four latitudinal range size quartiles, from the 25% species with the narrowest to the 25% with the widest range size. We found notable differences between patterns of total species richness and those of individual range size quartiles. Whereas total species richness was higher in more intervened land-use types, percentages of narrow-ranged species were significantly higher in less intervened land-use types. In contrast, percentages of wide-ranging species were higher in more intervened land-use types. Hence, responses of plant species to human activities were influenced by traits that determine their range sizes. An analysis of floristic similarity between land-use types revealed that narrow-ranged species were mainly preserved in forest fragments, but the other land-use types supported many unique narrow-ranged species and therefore made an important contribution to their preservation at the landscape level. Conservation efforts should combine protection of natural habitats with strategies to maintain a diversity of low-intensity land-use types, looking for win-win solutions or trade-offs between biodiversity conservation and human welfare in human-dominated landscapes. 相似文献
5.
Cultural transmission of ethnobotanical knowledge in a rural community of northwestern Patagonia, Argentina 总被引:2,自引:0,他引:2
In the present study we analyzed medicinal and edible plant utilization in Cuyin Manzano, a small rural population located
near the Andean forests of Argentina. We also studied where and when plant knowledge was learned, who the principal transmitters
were, and how people were taught. The participants were interviewed individually and at random, by means of a semi-structured
questionnaire. Interviews were carried out in 16 families in order to examine the present use of wild plants. The inhabitants
of Cuyin Manzano cited 87 plants: 63 medicinal and 24 edible species. They mentioned on average 31 ± 10 species per person.
Similar patterns of plant use were found in young and old people alike, irrespective of gender. Learning about useful plants
took place at an early age as a result of family tradition. This local knowledge is acquired and taught “by doing,” and is
mostly transmitted vertically through family dissemination. Wild plant learning implies the acquisition of plants' physical
and functional features as well as their environmental characteristics. 相似文献
6.
Olga De Castro Antonietta Di Maio José Armando Lozada García Danilo Piacenti Mario Vázquez-Torres Paolo De Luca 《Annals of botany》2013,112(3):589-602
Background and Aims
Recent research on the history of Platanus reveals that hybridization phenomena occurred in the central American species. This study has two goals: to help resolve the evolutive puzzle of central American Platanus, and to test the potential of real-time polymerase chain reaction (PCR) for detecting ancient hybridization.Methods
Sequencing of a uniparental plastid DNA marker [psbA-trnH(GUG) intergenic spacer] and qualitative and quantitative single nucleotide polymorphism (SNP) genotyping of biparental nuclear ribosomal DNA (nrDNA) markers [LEAFY intron 2 (LFY-i2) and internal transcribed spacer 2 (ITS2)] were used.Key Results
Based on the SNP genotyping results, several Platanus accessions show the presence of hybridization/introgression, including some accessions of P. rzedowskii and of P. mexicana var. interior and one of P. mexicana var. mexicana from Oaxaca (= P. oaxacana). Based on haplotype analyses of the psbA-trnH spacer, five haplotypes were detected. The most common of these is present in taxa belonging to P. orientalis, P. racemosa sensu lato, some accessions of P. occidentalis sensu stricto (s.s.) from Texas, P. occidentalis var. palmeri, P. mexicana s.s. and P. rzedowskii. This is highly relevant to genetic relationships with the haplotypes present in P. occidentalis s.s. and P. mexicana var. interior.Conclusions
Hybridization and introgression events between lineages ancestral to modern central and eastern North American Platanus species occurred. Plastid haplotypes and qualitative and quantitative SNP genotyping provide information critical for understanding the complex history of Mexican Platanus. Compared with the usual molecular techniques of sub-cloning, sequencing and genotyping, real-time PCR assay is a quick and sensitive technique for analysing complex evolutionary patterns. 相似文献7.
The multiple use of distinct ecological environments in the search for wild resources has been practiced since ancestral times in aboriginal communities inhabiting northwestern Patagonia. This paper examines the actual use and knowledge of wild edible plants in a Mapuche community presently settled in one of the most arid areas of Patagonia, far from the temperate forests where their ancestors used to live. The difference between knowledge of and use of wild plants is analyzed emphasizing that these differences could contribute to the understanding of eroding processes believed to be occurring in the community. These objectives are studied quantitatively by utilizing ethnobotanical indices, partially derived from ecological theory. Our results indicate that the Paineo dwellers still utilize multiple ecological gathering environments and have thorough plant knowledge of both native and exotic species. The Andean forest, more than 50km away from this community, is the environment from which the Paineo dwellers know the greatest total richness and the highest diversity of wild edible plants, followed by the Monte–Steppe species and lastly, those growing around their homes. The transmission of wild edible plant knowledge in the Paineo community diminishes with age, and the forest plants are the most vulnerable to loss. Our results have shown that the knowledge and consumption of wild edible plants follows a pattern according to ecological conditions of the gathering environments, as well as the cultural heritage of the Paineo people. 相似文献
8.
Li Z Mehdi S Patel I Kawooya J Judkins M Zhang W Diener K Lozada A Dunnington D 《Journal of biomolecular screening》2000,5(1):31-38
We have developed a novel assay for measuring the activity of an enzyme that transfers multiple adenine-containing groups to an acceptor protein. The assay is based on fluorescence polarization (FP) technology in a 1536-well plate format. In the assay, a long wavelength fluorescence tracer, Texas Red (Rhodamine), was covalently conjugated to adenine of the donor substrate through a C(6) spacer arm. As a result of the transfer of the adenine-containing moieties to the acceptor protein substrate, the rotational correlation time of the Texas Red conjugate increased, hence increasing the degree of fluorescence polarization. The pharmacological profile and kinetics of the enzyme measured according to the FP method were consistent with those determined previously by conventional analysis. We have successfully executed a 250,000-compound high throughput screening program based on the FP assay method. The quality and validity of the assay were verified by a variety of statistical analyses. 相似文献
9.
Metagenomics reveals the high polycyclic aromatic hydrocarbon‐degradation potential of abundant uncultured bacteria from chronically polluted subantarctic and temperate coastal marine environments 下载免费PDF全文
10.
María B. Yossen Mariana Lozada Marcelo N. Kuperman Silvia Gonzlez Bruno Gastaldi Micaela Buteler 《Journal of Applied Entomology》2019,143(6):635-643
Recently, plant‐based repellents have been proposed as a potential alternative to classic pesticides against pest wasps, in certain scenarios. Here, the repellent effect of Dysphania multifida essential oil and one of its main terpenoid components, α‐terpinene, were tested under field conditions with natural populations of wasps in Patagonia Argentina. D. multifida essential oil (paico), as well as α‐terpinene, repelled V. germanica wasps in the field. A strong avoidance of food baits treated with the essential oil or α‐terpinene was observed in choice and no‐choice tests. In no‐choice tests, the time it took wasps to arrive at the bait was significantly greater in treated baits than in control baits. Also, the total number of arriving wasps in 30 min was significantly greater in untreated baits in comparison with treated baits, under similar environmental conditions and wasp density. As the wasps’ flight season progressed, wasp density and motivation for proteinaceous food sources increased. This was evidenced by a greater total number of wasps in untreated baits with time. On the contrary, the number of wasps in treated baits remained low throughout the peak season. Both the paico essential oil and the α‐terpinene act as powerful repellents for V. germanica wasps, generating an avoidance response to treated food sources. Thus, these compounds have potential to be used as repellents to prevent wasps’ approaches and foraging, when applied in close proximity to a food source. 相似文献