341,650 research outputs found
Spontaneous gene flow and population structure in wild and cultivated chicory, Cichorium intybus L.
No full textSpontaneous gene flow between wild and cultivated chicory, Cichorium intybus L., may have implications for the genetic structure and evolution of populations and varieties. One aspect of this crop-wild gene flow is the dispersal of transgenes from genetically modified varieties, e.g. gene flow from GM chicory to natural chicory could have unwanted consequences. With the purpose to identify and quantify crop-wild gene flow in chicory, we analysed introgression in 19 wild chicory populations and 16 accessions of chicory varieties and landraces distributed across Northern, Central and Mediterranean Europe. The analysis used 281 AFLP markers and 75 SSAP markers giving a total of 356 polymorphic markers. Results from model based assignments with the program STRUCTURE indicated many incidents of recent gene flow. Gene flow was observed both between cultivars and wild populations, between landraces and wild populations, between different wild populations as well as between cultivars. Population structure visualized by distance-based clustering showed a North–South geographical structuring of the wild populations, and a general grouping of the cultivars corresponding to known origin. The results indicated, however, that the structuring between the two groups of wild and cultivated types was weak. As crop and wild recipients are genetically close and genes are transferred between the two types rather frequently, focus on mitigating crop-wild gene flow should be increased, before transgenic varieties are cultivated openly
Dioptra o alidada
No full textLlautó, ferro, vidreAlidada per treballar amb planxeta. Està fabricada per Wild; però el segell podria estar tapat per la pintura.Longitud de l’ocular: 19.5 cm. Augment: x 24.32 x 12 x 16 c
Molecular characterization of Cryptosporidium spp. from wild rats and mice from rural communities in the Philippines
No full textIn order to examine the prevalence of Cryptosporidium in wild rodents in the Philippines and understand the role wild rodents play in the transmission of this parasite to humans and livestock, 194 fecal samples from wild rats and mice from Luzon and Mindoro islands were examined. Molecular screening at the 18S and actin gene loci identified an overall prevalence of 25.8% (95%CI: 19.8, 32.5). Sequence and phylogenetic analysis of both loci identified C. parvum, C. muris, C. scrofarum, rat genotypes I-IV and a C. suis-like genotype in the rat-derived isolates and is the first report of C. suis-like and C. scrofarum in rats. Mixed infections were identified in 24% of the Cryptosporidium positive isolates. Rat genotypes II, III and IV showed high intragenotypic variation at the 18S gene locus compared to the actin locus
Vorstellung verschidener Chrono-Magischen Quadraten : Deren die erste Zehen von 25 Fächlein, und folgende Vier von 49 Fächlein, so man aufwerts, über die Seiten, und auch NB. über das Creutz (nemlich von A zum D, und vom B bis C) addirt, oder summiert, machen sammentlich 184. mahl das letzlich verflossene Jubel-Jahr aus, nemlich 1750. ...
No full textEntworffen Von P. Friderico Wild, p. t. Procuratore Ord. Min. S. Francisci Conv
Vaccination strategies to conserve the endangered African wild dog (Lycaon pictus)
No full textPathogens such as rabies virus and canine distemper virus present a significant risk to the long-term survival of some endangered African wild dog (Lycaon picrus) populations. Vaccination of wild dogs is one approach that might reduce population extinction risks; however clear guidelines for how best to do this are lacking. Hence, we developed a mathematical model of wild dog population dynamics that integrates a pathogen transmission model and a vaccination process. Simulations indicated that the most effective vaccination strategy includes all age classes (when pups are 2-months old), prioritizes the breeding pair, and vaccinates at least 4 animals per pack included in the vaccination effort. In addition, populations for which an Allee effect, high rates of pathogen introduction, or low rates of recovery and immunity were simulated, required greater vaccination coverage (dogs/pack), to protect an equivalent number of packs compared to populations for which no Allee effect, low rates of pathogen introduction, or high rates of recovery and immunity were simulated. For populations in which some packs (high-risk) have a greater risk of pathogen exposure than others (low-risk), vaccinating both high- and low-risk packs, or only low-risk packs, is more effective than vaccinating only high-risk packs when pathogen introduction rates are high. Finally, model results suggest that vaccination of wild dog populations against pathogens, such as canine distemper virus, that do not cause 100% mortality and against which some wild dogs develop acquired immunity, may be unnecessary. (C) 2011 Elsevier Ltd. All rights reserve
Identifying realistic recovery targets and conservation actions for tigers in a human dominated landscape using spatially-explicit densities of wild prey and their determinants
No full textAim
Setting realistic population targets and identifying actions for site and landscape-level recovery plans are critical for achieving the global target of doubling wild tiger numbers by 2022. Here, we estimate the spatially explicit densities of wild ungulate prey across a gradient of disturbances in two disjunct tiger habitat blocks (THBs) covering 5212 km2, to evaluate landscape-wide conditions for tigers and identify opportunities and specific actions for recovery.
Location
Western Terai Arc Landscape, India.
Methods
Data generated from 96 line transects in 15 systematically selected geographical cells (166.5 km2) were used to estimate spatially explicit densities of six wild ungulate prey species at a fine scale (1 km2). Employing distance-based density surface models, we derived species-specific estimates within three major forest land management categories (inviolate protected areas (PA), PAs with settlements and multiple-use forests). By scaling estimated prey densities using an established relationship, we predicted the carrying capacity for tigers within each THB.
Results
Species-specific responses of the six wild ungulates to natural-habitat and anthropogenic covariates indicated the need for targeted prey recovery strategies. Inviolate PAs supported the highest prey densities compared with PAs with settlements and multiple-use forests, and specifically benefited the principal tiger prey species (chital Axis axis and sambar Rusa unicolor). The estimated mean prey density of 35.16 (±5.67) individuals per km2 can potentially support 82 (62–106) and 299 (225–377) tigers across THB I and THB II, which currently support 2 (2–7) and 225 (199–256) tigers, respectively. This suggests a potential c. 68% increase in population size given existing prey abundances. Finally, while THB I represents a potential tiger recovery site given adequate prey, PAs where resettlement of pastoralists is underway represent potential prey recovery sites in THB II.
Main conclusions
This systematic approach of setting realistic population targets and prioritizing spatially explicit recovery strategies should aid in developing effective landscape conservation plans towards achieving global tiger conservation targets
Preventing wild boar "Sus scrofa" damage - considerations for wild boar management in highly fragmented agroecosystems
No full textDuring the last three decades wild boar populations have grown rapidly and the range of the species has increased steadily, covering almost the whole European continent today. The huge spread of the wild boar and the high population densities pose major problems, particularly to agriculture. Wild boars cause considerable damage to fields and grassland, but also pose a potentially high threat to livestock, as carrier of the pathogen of the classical swine fever, which may be transmitted to domestic pigs and can cause huge losses. To prevent economic problems by high wild boar populations, an effective wild boar management has to be established. Besides the regulation of the populations by means of hunting, vulnerable crop fields have to be protected adequately. Crop protection is usually achieved by the use of electric fences. Alternatively, various methods are available that claim effective deterrence of wild boars, however, most of which lacking scientific proof of effectiveness.
This thesis, based on a field study conducted in the Canton Basel-Land, northwestern Switzerland, presents research results on the effectiveness of three different deterrent systems: solar-powered blinkers, an odour repellent, and a gustatory repellent. The aims of the study were: (1) to investigate three means to deter wild boars from agricultural land representative for other deterrents based on optic, olfactory, or gustatory effects; (2) to provide relevant and evidence-based data, which contribute to the policy and practice of wild boar management and damage prevention in the Canton Basel-Land, also applicable to other regions. I discussed the results in a broader context, also considering the role of hunting in damage prevention.
Solar blinkers and the odour repellent, which were investigated at baited luring sites, reduced the probability of wild boar visits by 8.1% and by 0.4% respectively. Both deterrents were not effective in preventing wild boars from accessing the lure food. Additionally, we did not find any initial deterrence effect. The gustatory repellent, which was investigated in experimental fields, did not have a significant effect on the frequency of damage events. Although we observed a slight trend towards a damage reduction, the results show, that the repellent was not able to prevent damage. We further could not detect any area avoidance by the wild boars as a response to the repellent.
The present study revealed, that none of the deterrents investigated was able to prevent wild boars from entering the experimental sites. Hence the deterrents in question are no effective means for field protection. Moreover, I suggest that any other deterrent basing on startling response, neophobia, fear-evocation, or conditioned avoidance would not be effective in preventing wild boars from entering agricultural land. To date, the only recommendable means for damage prevention is the electric fence, which should be taken into account by the responsible authorities. Based on the findings of the present study, farmers must be discouraged from the use of other deterrents than electric fences to protect their fields. Additionally, damage compensation should be subject to the condition of fencing of the fields.
Besides the protection of vulnerable crops the reduction of wild boar populations by means of hunting is crucial for damage prevention. Hunting rates have to be increased and hunting effort should focus on females of all age classes, but especially on juvenile females, which have shown to be highly reproductive and substantially contribute to population growth. For this purpose, selective hunting techniques like hide hunting and stalk hunting should be prioritised and promoted.
The highly reproductive wild boar possesses the ability to recover from population losses in a very short time. Hence, both effective hunting management and field protection will remain the most important tools for damage control. Further research is required to investigate and compare different wild boar management systems including also damage prevention under an economic perspective. Stakeholders like farmers, hunters, and authorities must be involved.
The omnivore wild boar is enabled to adapt to various environments. Wild boar populations are expected to increase further and to spread into areas not yet populated. In Switzerland, the spread into the central parts of the country will also be supported by additional wildlife crossings that are in construction or in process of planning which will pose a challenge for wildlife management in these regions
Electronic properties of boron-doped diamond on the border between the normal and the superconducting state
No full textWe report on measurements of resistivity and magnetoresistivity, Hall effect and upper critical field on normal and superconducting heavily boron-doped diamond layer produced by microwave plasma assisted chemical vapour deposition. The magnetoresistivity shows a characteristic change as a function of the boron concentration with strong evidence for a closed Fermi surface for superconducting samples. Although experimental and theoretical results favour a conventional, weak coupling electron-phonon interpretation of the superconducting mechanism, the observed dependence of the transition temperature T-C on the hole concentration cannot be consistently described by the conventional theory. (c) 2005 Elsevier B.V. All rights reserved
Our Stories Are Wild
No full textCurated by Caroline Locke "Our Stories Are Wild", is an exhibition which brings together artists and researchers from Derbyshire, Nottinghamshire, Leicestershire, and, Staffordshire, who focus on the human-nature relationship. Many of the artworks and films reveal an emotional and spiritual connection with our environment and explore themes of care, hope and responsibility. The exhibition took place at Derby Cathedral over a five week period and included over 33 artists and collaborators. The exhibition brought together research and practice to coincide with the University of Derby’s Nature Connections Conference 2024
Wild-Type Cells 1-12
No full textFission yeast growth videos. Wild-type cells growing in rich medium (YES) at 30˚C.<br
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