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441.
442.
The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes species of medical and veterinary importance. The presence of Anaplasma spp. in ticks from birds, as well as in Haemaphysalis punctata (Ixodida: Ixodidae) specimens collected from cattle and vegetation in northern Spain was investigated. A total of 336 ticks from birds [174 Ixodes frontalis (Ixodida: Ixodidae), 108 H. punctata, 34 Hyalomma marginatum (Ixodida: Ixodidae), 17 Ixodes ricinus (Ixodida: Ixodidae) and three Ixodes spp.], and 181 H. punctata specimens collected from cattle (n = 71) and vegetation (n = 110) were analysed. Anaplasma bovis was detected in five H. punctata, including two from birds (1.9%) and three from vegetation (2.7%). Four I. frontalis (2.3%) (one co‐infected with ‘Candidatus Midichloria mitochondrii’) and one I. ricinus (5.9%) removed from birds, as well as four H. punctata (5.6%) collected from cattle showed Anaplasma phagocytophilum infection. In addition, Anaplasma centrale was found in two H. punctata, one from a cow (1.4%) and the other from vegetation (0.9%). This study represents the first evidence of the presence of A. bovis in European ticks, and reports the first detection of A. bovis and A. centrale in H. punctata, and the first finding of A. phagocytophilum and ‘Ca. Midichloria mitochondrii’ in I. frontalis.  相似文献   
443.
The installation of nestboxes is a widely used conservation measure for enhancing habitat suitability for cavity‐nesting birds wherever natural holes are scarce. However, nestboxes may attract birds to unsuitable breeding places or induce a non‐random distribution of individuals in relation to their qualities. We investigated the factors influencing nestbox selection and the quality of breeding territories for the globally near‐threatened Eurasian Roller in a semi‐arid area of southeast of Spain over a 3‐year period. Rollers preferentially used exposed nestboxes that were placed far from highly modified areas. However, breeding success was significantly lower in exposed nestboxes. Early breeders preferred nestboxes oriented to the northwest over any other orientation. Exposure had opposite effects on nestbox use and breeding success, suggesting that nestboxes installed in exposed sites could function as ecological traps for Rollers.  相似文献   
444.
The adaptive benefit of stomatal crypts remains a matter of controversy. This work studies the effect on gas exchange of cuticular rims that overarch the stomatal pore in the Mediterranean species Quercus coccifera L. growing under Mediterranean (lower relative humidities and high summer temperatures) or oceanic conditions (higher daily relative humidities and mild temperatures). After microscopic assessment of the leaf surfaces and stomatal architecture, the impact of the cuticular ‘cup’ on gas exchange was evaluated by employing three‐dimensional finite element models. Here, we provide evidence for a high plasticity of the Q. coccifera cuticular cup, with much larger vents under oceanic conditions compared to small vents under Mediterranean conditions. This structure adds a substantial fixed resistance thereby strongly decreasing gas exchange under Mediterranean conditions. The cuticular cup, which also increases leaf internal humidity, might buffer the rapid changes in vapour pressure deficit (VPD) often observed under Mediterranean conditions. Since water loss of guard and adjacent epidermal cells regulates stomatal aperture, we suggest that this structure allows an efficient regulation of stomatal conductance and optimum use of resources under high VPD. This study provides evidence that plasticity of stomatal architecture can be an important structural component of hydraulic adaptation to different climate conditions.  相似文献   
445.
1. In the current ecological classification of termites, four feeding groups (I–IV) are recognised, corresponding to a gradient of decomposition from sound wood to highly mineralised organic matter in the soil. 2. Nitrogen stable isotopes (hereafter δ15N) were used to place termites from French Guiana rainforests along a wood‐soil decomposition gradient, to test (i) whether feeding group assignation based on morphological characters was accurate and actually represented diet specialisation thresholds, and (ii) to what extent the dietary specialization of species is explained by phylogeny (phylogenetic autocorrelation). 3. δ15N values vary over a range of 13‰, suggesting that diet diversification contributes to the high species diversity in French Guiana. δ15N values span a similar interval in all Termitidae subfamilies. Ranges of different subfamilies broadly overlap, although each of them diversified preferentially on one side of the wood‐soil decomposition gradient. Congeneric species share similar feeding habits, whereas distant species tend to feed on distinct substrates. 4. Feeding groups did not completely match stable isotope data: there was no discontinuity between Groups III and IV, and no correlation between anatomical criteria used to distinguish these groups and δ15N values. Nor was there any consistent difference in δ15N values between wood feeders of the families Rhinotermitidae (Group I) and Termitidae (Group II). We also suggest that species feeding outside the wood‐soil gradient should be distinguished for their peculiar feeding requirements.  相似文献   
446.
447.
Using Drosophila melanogaster, we explore the consequences of restricted panmixia (RP) on the genetic load caused by segregating deleterious recessive alleles in a population where females mate a full sib with probability about ½ and mate randomly otherwise. We find that this breeding structure purges roughly half the load concealed in heterozygous condition. Furthermore, fitness did not increase after panmixia was restored, implying that, during RP, the excess of expressed load induced by inbreeding had also been efficiently purged. We find evidences for adaptation to laboratory conditions and to specific selective pressures imposed by the RP protocol. We discuss some of the consequences of these results, both for the evolution of population breeding structures and for the design of conservation programmes.  相似文献   
448.
ABSTRACT Capturing animals is an essential tool of wildlife management, but the use of capture devices is being affected by public pressures on an international scale. In Europe, and particularly Spain, foxes (Vulpes vulpes) are often captured using traditional methods such as nonlocking Spanish Snares (SS) set in an ad hoc fence line known as an alar, but these traditional European methods are rarely compared to modernly described restraints such as the Wisconsin Cable Restraint (WR). We evaluated rates of efficiency, selectivity, injury, and impacts to foxes and nontarget species when using SS (as traditionally set in an alar) or WR within alars or on trails in Castilla-La Mancha, Spain. During 40,372 trap-nights from summer to winter of 2007, we captured 64 foxes, and 8 of 23 potential nontarget species. Our results indicated that WR set in trails were more efficient (0.28 capture rate) for capturing red foxes than SS set in an alar (0.11 capture rate). Relative to injury, foxes captured with the WR in the alar (95.4%), and WR in trails (90.5%), and the SS (90.9%) showed no indicators of poor welfare, and injury score analysis indicated that injuries were of similar magnitude for all capture devices. Overall, the WR set in trails may have performed the best, but all 3 methods are likely sufficient for capturing foxes with minimal injury, acceptable efficiency, and acceptable impact to foxes and sympatric nontarget species. Thus, wildlife managers in Spain and elsewhere can apply our findings to optimize capture and management of foxes.  相似文献   
449.
Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is a species of mosquito that is currently widespread in Mexico. Historically, the mosquito has been distributed across most tropical and subtropical areas lower than 1700 m a.s.l. Currently, populations that are found at higher altitudes in regions with cold and dry climates suggest that these conditions do not limit the colonization and population growth of S. aegypti. During a survey of mosquitoes in September 2015, larvae of S. aegypti mosquitoes were found in two different localities in Mexico City, which is located at about 2250 m a.s.l. Mexico City is the most populous city in Mexico and has inefficient drainage and water supply systems. These factors may result in the provision of numerous larval breeding sites. Mosquito monitoring and surveillance are now priorities for the city.  相似文献   
450.
Current developments in biomedicine are presenting us with difficult ethical decisions and raising complex policy questions about how to regulate these new developments. Particularly vexing for governments have been issues related to human embryo experimentation. Because some of the most promising biomedical developments, such as stem cell research and nuclear somatic transfer, involve such experimentation, several international bodies have drafted documents aimed to provide guidance to governments when developing biomedical science policy. Here I focus on two such documents: the Council of Europe's Convention for the Protection of Human Rights and Dignity of the Human Being and the Additional Protocol to the Convention for the Protection of Human Rights and Dignity of the Human Being. I argue that by using human dignity as a criterion to determine the permissibility of particular human embryo research practices, these documents cannot aid in identifying research that would be contrary to human dignity. Thus, they fail to guide public policy on embryo experimentation. Their use of human dignity as a criterion makes their task of offering guidance unfeasible because the concept as used in these documents is too vague and is applied in contradictory ways. I discuss the main goals of these documents and their claims in relation to human embryo research. I then discuss how they have influenced public policy in several countries. Finally, I show that although these Council of Europe treaties attempt to serve as public policy guides in the area of embryo research, they fail to do so.  相似文献   
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