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161.
Constantí Stefanescu Ferran Páramo Susanne Åkesson Marta Alarcón Anna Ávila Tom Brereton Jofre Carnicer Louis F. Cassar Richard Fox Janne Heliölä Jane K. Hill Norbert Hirneisen Nils Kjellén Elisabeth Kühn Mikko Kuussaari Matti Leskinen Felix Liechti Martin Musche Eugenie C. Regan Don R. Reynolds David B. Roy Nils Ryrholm Heiko Schmaljohann Josef Settele Chris D. Thomas Chris van Swaay Jason W. Chapman 《Ecography》2013,36(4):474-486
Long‐range, seasonal migration is a widespread phenomenon among insects, allowing them to track and exploit abundant but ephemeral resources over vast geographical areas. However, the basic patterns of how species shift across multiple locations and seasons are unknown in most cases, even though migrant species comprise an important component of the temperate‐zone biota. The painted lady butterfly Vanessa cardui is such an example; a cosmopolitan continuously‐brooded species which migrates each year between Africa and Europe, sometimes in enormous numbers. The migration of 2009 was one of the most impressive recorded, and thousands of observations were collected through citizen science programmes and systematic entomological surveys, such as high altitude insect‐monitoring radar and ground‐based butterfly monitoring schemes. Here we use V. cardui as a model species to better understand insect migration in the Western Palaearctic, and we capitalise on the complementary data sources available for this iconic butterfly. The migratory cycle in this species involves six generations, encompassing a latitudinal shift of thousands of kilometres (up to 60 degrees of latitude). The cycle comprises an annual poleward advance of the populations in spring followed by an equatorward return movement in autumn, with returning individuals potentially flying thousands of kilometres. We show that many long‐distance migrants take advantage of favourable winds, moving downwind at high elevation (from some tens of metres from the ground to altitudes over 1000 m), pointing at strong similarities in the flight strategies used by V. cardui and other migrant Lepidoptera. Our results reveal the highly successful strategy that has evolved in these insects, and provide a useful framework for a better understanding of long‐distance seasonal migration in the temperate regions worldwide. 相似文献
162.
PYRABACTIN RESISTANCE1-LIKE8 Plays an Important Role for the Regulation of Abscisic Acid Signaling in Root 总被引:2,自引:0,他引:2
163.
Alexandre Alberto Tonin Aleksandro Schafer da Silva Maria Luiza Thorstenberg Lívia Gelain Castilhos Raqueli Teresinha Fran?a Daniela Bitencourt Rosa Leal Marta Maria Medeiros Frescura Duarte Fernanda Silveira Flores Vogel Mario Luiz de La Rue Sonia Terezinha dos Anjos Lopes 《The Korean journal of parasitology》2013,51(4):421-426
Several studies have shown the mechanisms and importance of immune responses against Toxoplasma gondii infection and the notable role of cholinesterases in inflammatory reactions. However, the association between those factors has not yet been investigated. Therefore, the aim of this study was to evaluate the acetylcholinesterase (AChE) activity in blood and lymphocytes and the activity of butyrylcholinesterase (BChE) in serum of rats experimentally infected with T. gondii during the acute phase of infection. For that, an in vivo study was performed with evaluations of AChE and BChE activities on days 5 and 10 post-infection (PI). The activity of AChE in blood was increased on day 5 PI, while in lymphocytes its activity was enhanced on days 5 and 10 PI (P<0.05). No significant difference was observed between groups regarding to the activity of BChE in serum. A positive (P<0.01) correlation was observed between AChE activity and number of lymphocytes. The role of AChE as an inflammatory marker is well known in different pathologies; thus, our results lead to the hypothesis that AChE has an important role in modulation of early immune responses against T. gondii infection. 相似文献
164.
Mauro I. Schiaffini Magalí Gabrielli Francisco J. Prevosti Yamila P. Cardoso Diego Castillo Roberto Bo Emma Casanave Marta Lizarralde 《Zoological Journal of the Linnean Society》2013,167(2):327-344
Despite recent taxonomic evaluations of Mephitidae and North American hog‐nosed skunks, southern South American species of Conepatus have not been thoroughly examined in a systematic context. Conepatus chinga and Conepatus humboldtii were described more than 150 years ago, based on external characters such as hair coloration and size. Although historically recognized as valid species, to date no detailed systematic analysis has been performed for either of these taxa. Herein, we evaluated the taxonomic status of C. chinga and C. humboldtii within the southern part of South America using geometric morphometrics of the skull and mandible, mitochondrial DNA analysis using the cytochrome b and cytochrome oxidase c subunit I genes, and also control region and pelage pattern variation. We failed to find morphological (skull shape and pelage coloration patterns) or molecular differences between these two species; thus, we considered that the specimens assigned to C. chinga and C. humboldtii belong to the same species. Our results indicate that environmental variation seems to be responsible for shape and size variation in Conepatus skulls from southern South America. © 2013 The Linnean Society of London 相似文献
165.
Species richness and endemicity in the Spanish vascular flora 总被引:1,自引:0,他引:1
Data from an updated and revised checklist of the Spanish flora is analyzed. The Spanish vascular plant flora is composed of 204 families, 1433 genera and 7071 species. Floristic data are analysed by considering three regions: mainland Spain with 5984 species, the Balearic Islands with 1521 species and Canary Islands with 2066 species. Extinct species are included in the analysis, with an extinction rate of 0.35% of the flora. A total of 1488 endemic species are recognized, which account for 21% of the Spanish flora. The rate of endemism in the Canary Islands is 25.9%, considerably higher than for the Balearic Islands (6.9%) and for mainland Spain (13.8%). A list of the 35 strict endemic genera is compiled, of which 65.7% are Canarian, and another list of 27 subendemic genera of which 48.1% are also Canarian. An estimated 12% of the Spanish flora is non‐native, with large variation between the 20.7% of the Canary flora, 10.5% of mainland Spain and 9.7% of the Balearic Islands. Finally, the composition of the Spanish flora for large groups and families is ana lysed. The data show that species richness and endemicity rates have been overestimated by previous authors, and are similar to other Mediterranean countries. It is concluded that a complete revision of the Macaronesian flora is strongly needed to obtain an accurate comparison with the flora of other areas. 相似文献
166.
This article is based on the theoretical framework developed within a research project on the construction of Eurocentrism and, more specifically, on the analysis of Portuguese history textbooks. We propose that the textbooks’ master narrative constitutes a power-evasive discourse on history, which naturalizes core processes such as colonialism, slavery and racism. Showing the limits of an approach that merely proposes the compensation or rectification of (mis)representations, we argue for the need to unbind the debate on Eurocentrism from a perspective that fails to make problematic the ‘very idea of Europe’. Accordingly, our analysis of Portuguese history textbooks focuses on three core narrative devices: (1) the chronopolitics of representation; (2) the paradigm of the (democratic) national state; and (3) the definitive bond between concepts and historical processes. 相似文献
167.
Qiaoqiao Xu Shanshan Huang Mingke Song Chuan-En Wang Sen Yan Xudong Liu Marta A. Gaertig Shan Ping Yu He Li Shihua Li Xiao-Jiang Li 《The Journal of cell biology》2013,202(7):1123-1138
Many genetic mouse models of Huntington’s disease (HD) have established that mutant huntingtin (htt) accumulates in various subcellular regions to affect a variety of cellular functions, but whether and how synaptic mutant htt directly mediates HD neuropathology remains to be determined. We generated transgenic mice that selectively express mutant htt in the presynaptic terminals. Although it was not overexpressed, synaptic mutant htt caused age-dependent neurological symptoms and early death in mice as well as defects in synaptic neurotransmitter release. Mass spectrometry analysis of synaptic fractions and immunoprecipitation of synapsin-1 from HD CAG150 knockin mouse brains revealed that mutant htt binds to synapsin-1, a protein whose phosphorylation is critical for neurotransmitter release. We found that polyglutamine-expanded exon1 htt binds to the C-terminal region of synapsin-1 to reduce synapsin-1 phosphorylation. Our findings point to a critical role for synaptic htt in the neurological symptoms of HD, providing a new therapeutic target. 相似文献
168.
Marta R. Hentschke Carlos E. Poli-de-Figueiredo Bartira E. Pinheiro da Costa Lesia O. Kurlak Paula J. Williams Hiten D. Mistry 《Journal of lipid research》2013,54(10):2658-2664
Atherosis of spiral arteries in uteroplacental beds from preeclamptic women resemble those of atherosclerosis, characterized by increased plasma lipids and lipoproteins. We hypothesized that: 1) lipoprotein receptors/transporters in the placenta would be upregulated in preeclampsia, associated with increased maternal and fetal lipoprotein concentrations; and 2) expression of these would be reduced in preeclamptic placentae from women delivering small-for-gestational-age (SGA) infants. Placental biopsies and maternal and umbilical serum samples were taken from 27 normotensive and 24 preeclamptic women. Maternal/umbilical cord serum LDL, HDL, total cholesterol, and triglycerides were measured. Placental mRNA expression of lipoprotein receptors/transporters were quantified using quantitative RT-PCR. Protein localization/expression of LDL receptor-related protein 1 (LRP-1) in the preeclamptic placentae with/without SGA was measured by immunohistochemistry. Placental mRNA expression of all genes except paraoxonase-1 (PON-1), microsomal triglyceride transfer protein (MTTP), and protein disulfide isomerase family A member 2 (PDIA2) were observed. No differences for any lipoprotein receptors/transporters were found between groups; however, in the preeclamptic group placental LRP-1 expression was lower in SGA delivering mothers (n = 7; P = 0.036). LRP-1 protein was localized around fetal vessels and Hofbauer cells. This is the first detailed study of maternal/fetal lipoprotein concentrations and placental lipoprotein receptor mRNA expression in normotensive and preeclamptic pregnancies. These findings do not support a role of altered lipid metabolism in preeclampsia, but may be involved in fetal growth. 相似文献
169.