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961.
962.
Norbert Maczey Steve Edgington Dave Moore Tim Haye 《Biocontrol Science and Technology》2016,26(4):447-461
The European earwig (Forficula auricularia) is an invasive species in the Falkland Islands, causing considerable problems for local horticulture, as well threatening indigenous ecosystems. To assess the potential of a classical biological control introduction two parasitoid fly species, Triarthria setipennis and Ocytata pallipes (Diptera: Tachinidae), were collected from sites in southern and northern England and then tested for their suitability as earwig biological controls at Egham, UK. Both species had previously been introduced into North America for earwig control however little is known of their long-term efficacy and host specificity. Host range tests including both target and non-target species were done. As there are no native Dermaptera on the Falkland Islands, tests were restricted to the field cricket Gryllus assimilis and the Dubia cockroach Blaptica dubia, as representatives of insect orders phylogenetically closely related to earwigs. A second cricket species (Gryllus bimaculatus) was included in an egg-depositing experiment for O. pallipes. Both tachinid species successfully parasitised and emerged from earwigs under laboratory conditions but no signs of parasitisation and development were observed in either the cricket or cockroach. 相似文献
963.
The Cooling Trend of Canopy Temperature During the Maturation,Succession, and Recovery of Ecosystems
Hua Lin Zexin Fan Leilei Shi Altaf Arain Harry McCaughey Dave Billesbach Mario Siqueira Rosvel Bracho Walter Oechel 《Ecosystems》2017,20(2):406-415
The maximum exergy dissipation theory provides a theoretical basis for using surface temperature to measure the status and development of ecosystems, which could provide an early warning of rapid evaluation of ecosystem degradation. In the present study, we used the radiation balance of ecosystems to demonstrate this hypothesis theoretically. Further, we used empirical data to verify whether ecosystems gain more radiation, while lowering their surface temperatures, as they develop naturally. We analyzed 12 chronosequences from the FLUXNET database using meteorological data and heat fluxes. We included age, disturbance, and successional chronosequences across six climate zones. Net radiation (R n) and the ratio of net radiation to global radiation (R n/R g) were used to measure the energy gain of the ecosystems. The maximum daily air temperature above the canopy (T max) and thermal response number (TRN) were used to analyze the surface temperature trends with ecosystem natural development. The general trends of T max, TRN, R n, and R n /R g demonstrated that ecosystems become cooler and more stable, yet gain more energy, throughout their natural development. Among the four indicators, TRN showed the most consistent trends and highest sensitivity to ecosystem growth, succession, and recovery. Moreover, TRN was not significantly influenced by precipitation or wind. We propose that TRN can be used to rapidly evaluate or warn of ecosystem disturbance, senescence, and degradation without prior knowledge of species composition, nutrient status, and complex ecosystem processes. 相似文献
964.
965.
The study was aimed at investigating localized topical drug delivery to the breast via mammary papilla (nipple). 5-fluorouracil (5-FU) and estradiol (EST) were used as model hydrophilic and hydrophobic compounds respectively. Porcine and human nipple were used for in-vitro penetration studies. The removal of keratin plug enhanced the drug transport through the nipple. The drug penetration was significantly higher through the nipple compared to breast skin. The drug’s lipophilicity had a significant influence on drug penetration through nipple. The ducts in the nipple served as a major transport pathway to the underlying breast tissue. Results showed that porcine nipple could be a potential model for human nipple. The topical application of 5-FU on the rat nipple resulted in high drug concentration in the breast and minimal drug levels in plasma and other organs. Overall, the findings from this study demonstrate the feasibility of localized drug delivery to the breast through nipple. 相似文献
966.
Free‐roaming animal populations are hard to count, and professional experts are a limited resource. There is vast untapped potential in the data collected by nonprofessional scientists who volunteer their time to population monitoring, but citizen science (CS) raises concerns around data quality and biases. A particular concern in abundance modeling is the presence of false positives that can occur due to misidentification of nontarget species. Here, we introduce Integrated Abundance Models (IAMs) that integrate citizen and expert data to allow robust inference of population abundance meanwhile accounting for biases caused by misidentification. We used simulation experiments to confirm that IAMs successfully remove the inflation of abundance estimates caused by false‐positive detections and can provide accurate estimates of both bias and abundance. We illustrate the approach with a case study on unowned domestic cats, which are commonly confused with owned, and infer their abundance by analyzing a combination of CS data and expert data. Our case study finds that relying on CS data alone, either through simple summation or via traditional modeling approaches, can vastly inflate abundance estimates. IAMs provide an adaptable framework, increasing the opportunity for further development of the approach, tailoring to specific systems and robust use of CS data. 相似文献
967.
gesp: A computer program for modelling genetic effective population size,inbreeding and divergence in substructured populations 下载免费PDF全文
Fredrik Olsson Linda Laikre Ola Hössjer Nils Ryman 《Molecular ecology resources》2017,17(6):1378-1384
The genetically effective population size (Ne) is of key importance for quantifying rates of inbreeding and genetic drift and is often used in conservation management to set targets for genetic viability. The concept was developed for single, isolated populations and the mathematical means for analysing the expected Ne in complex, subdivided populations have previously not been available. We recently developed such analytical theory and central parts of that work have now been incorporated into a freely available software tool presented here. gesp (Genetic Effective population size, inbreeding and divergence in Substructured Populations) is R‐based and designed to model short‐ and long‐term patterns of genetic differentiation and effective population size of subdivided populations. The algorithms performed by gesp allow exact computation of global and local inbreeding and eigenvalue effective population size, predictions of genetic divergence among populations (GST) as well as departures from random mating (FIS, FIT) while varying (i) subpopulation census and effective size, separately or including trend of the global population size, (ii) rate and direction of migration between all pairs of subpopulations, (iii) degree of relatedness and divergence among subpopulations, (iv) ploidy (haploid or diploid) and (v) degree of selfing. Here, we describe gesp and exemplify its use in conservation genetics modelling. 相似文献
968.
Interaction of yellow fever virus French neurotropic vaccine strain with monkey brain: characterization of monkey brain membrane receptor escape variants 下载免费PDF全文
Ni H Ryman KD Wang H Saeed MF Hull R Wood D Minor PD Watowich SJ Barrett AD 《Journal of virology》2000,74(6):2903-2906
Binding of yellow fever virus wild-type strains Asibi and French viscerotropic virus and vaccine strains 17D and FNV to monkey brain and monkey liver cell membrane receptor preparations (MRPs) was investigated. Only FNV bound to monkey brain MRPs, while French viscerotropic virus, Asibi, and FNV all bound to monkey liver MRPs. Four monkey brain and two mouse brain MRP escape (MRP(R)) variants of FNV were selected at pH 7.6 and 6.0. Three monkey brain MRP(R) variants selected at pH 7.6 each had only one amino acid substitution in the envelope (E) protein in domain II (E-237, E-260, or E274) and were significantly attenuated in mice following intracerebral inoculation. Two of the variants were tested in monkeys and retained parental neurotropism following intracerebral inoculation at the dose tested. We speculate that this region of domain II is involved in binding of FNV E protein to monkey brain and is, in part, responsible for the enhanced neurotropism of FNV for monkeys. A monkey brain MRP(R) variant selected at pH 6.0 and two mouse brain MRP(R) variants selected at pH 7.6 were less attenuated in mice, and each had an amino acid substitution in the transmembrane region of the E protein (E-457 or E-458). 相似文献
969.
The contents of reducing sugars, proteins and ascorbic acid and the activities of protease, peroxidase, catalase, indole acetic
acid oxidase, ascorbic acid oxidase, succinic dehydrogenase and the rate of respiration were investigated in regenerating
and non-regenerating parts ofClerodendrum viscosum Vent. root cuttings. All the above variables have registered higher in the regenerating parts, particularly at the distal
end where roots appear, than in the non-regenerating parts of root cuttings. The contents of metabolites and the activities
of enzymes in the presence of endogenous cytokinins at the proximal end and auxins at the distal end, were compared and discussed
in relation to the initiation of shoots and roots at two ends of root cuttings. In general it was concluded that interacting
hormonal and nutritional factors must be appropriate to initiate shoots or roots in the root cuttings. 相似文献