distribution generators
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1st ed. xvii, 438 s., grafy, tab.
Understanding species' ability to colonize new habitats is a key knowledge allowing us to predict species' survival in the changing landscapes. However, most studies exploring this topic observe distribution of species in landscapes which are under strong human influence being fragmented only recently and ignore the fact that the species distribution in these landscapes is far from equilibrium. Oceanic islands seem more appropriate systems for studying the relationship between species traits and its distribution as they are fragmented without human contribution and as they remained unchanged for a long evolutionary time. In our study we compared the values of dispersal as well as persistence traits among 18 species pairs from the Canary Islands differing in their distribution within the archipelago. The data were analyzed both with and without phylogenetic correction. The results demonstrate that no dispersal trait alone can explain the distribution of the species in the system. They, however, also suggest that species with better dispersal compared to their close relatives are better colonizers. Similarly, abundance of species in the archipelago seems to be an important predictor of species colonization ability only when comparing closely related species. This implies that analyses including phylogenetic correction may provide different insights than analyses without such a correction and both types of analyses should be combined to understand the importance of various plant traits for species colonization ability.
- MeSH
- fylogeneze MeSH
- oceány a moře * MeSH
- ostrovy * MeSH
- rozšíření zvířat * MeSH
- šíření semen * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- oceány a moře * MeSH
- ostrovy * MeSH
Fungal species identities are often based on morphological features, but current molecular phylogenetic and other approaches almost always lead to the discovery of multiple species in single morpho-species. According to the morphological species concept, the ant-parasitic fungus Rickia wasmannii (Ascomycota, Laboulbeniales) is a single species with pan-European distribution and a wide host range. Since its description, it has been reported from ten species of Myrmica (Hymenoptera, Formicidae), of which two belong to the rubra-group and the other eight to the phylogenetically distinct scabrinodis-group. We found evidence for R. wasmannii being a single phylogenetic species using sequence data from two loci. Apparently, the original morphological description (dating back to 1899) represents a single phylogenetic species. Furthermore, the biology and host-parasite interactions of R. wasmannii are not likely to be affected by genetic divergence among different populations of the fungus, implying comparability among studies conducted on members of different ant populations. We found no differences in total thallus number on workers between Myrmica species, but we did observe differences in the pattern of thallus distribution over the body. The locus of infection is the frontal side of the head in Myrmica rubra and M. sabuleti whereas in M. scabrinodis the locus of infection differs between worker ants from Hungary (gaster tergites) and the Netherlands (frontal head). Possible explanations for these observations are differences among host species and among populations of the same species in (i) how ant workers come into contact with the fungus, (ii) grooming efficacy, and (iii) cuticle surface characteristics.
- MeSH
- Ascomycota fyziologie MeSH
- Formicidae mikrobiologie MeSH
- fylogeneze MeSH
- interakce hostitele a parazita * MeSH
- mykózy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Maďarsko MeSH
Phthalates are a class of compounds that have been extensively used as plasticizers in different applications. Several phthalates have been recognized as substances of very high concern (SVHCs) in the EU, because of their toxicity for reproduction. However, high amounts of other phthalates are still produced and imported in the European Economic Area. In China and the US, recent studies show increasing concentrations of several phthalates in the air and in human urine, respectively. The understanding of phthalate absorption, distribution, metabolism, and elimination ('pharmacokinetics') in the organism is still limited. Specifically, phthalate partitioning among tissues is insufficiently understood. Here, we estimate partition coefficient (PC) values for different phthalates by using five algorithms and compare them to experimental (in-vivo and in-vitro) PC values. In addition, we review all pharmacokinetic steps for phthalates in human and rat, based on data from 133 peer-reviewed publications. We analyze the factors that determine phthalate partitioning and pharmacokinetics. Four processes are particularly relevant to phthalate distribution: protein binding, ionization, passive partitioning, and metabolism in different tissues. The interplay of these processes needs to be better represented in methods for determining the PC values of phthalates. The hydrophobicity of phthalates affects all pharmacokinetic steps. The exposure route has an influence on specific steps of phthalate pharmacokinetics but generally does not affect the pattern of metabolites in urine. The age of the organism has an influence on phthalate metabolism. More studies on the protein-bound fraction of phthalates in plasma and pharmacokinetic studies following inhalation and dermal exposure are desirable.
OBJECTIVES: Oxime HI-6 DMS (dimethanesulfonate) is an asymmetric bis-pyridinium aldoxime and essential acetylcholinesterase (AChE) reactivator. The high effectiveness is due to its wide spectrum of therapeutic activity against different structures of nerve agents. Aim of this study was to compare plasma time profiles and tissue distribution (to delimitation of potential toxicity risks) after its intramuscular (i.m.) and intragastric (i.g.) administration to experimental pigs. METHODS: The study entered female Landrace pigs (Sus scrofa f. domestica), 4-5 months old animals, 29 +/- 3.2 kg of body weight. Before the HI-6 DMS administration (i.m. injection or i.g. using a gastric tube), vena auricularis was cannulated (under general anaesthesia) for collection of blood samples. The tissue distribution study was carried out at expected t-max. Concentrations of HI-6 DMS in blood plasma and other tissue samples were detected by means of HPLC method. RESULTS: Fast absorption after i.m. administration, relatively slow absorption and no even elimination after i.g. administration were found. Tissue distribution showed low accumulation in the liver, but a higher content in the kidneys and high concentrations in the brain and gastrointestinal wall. CONCLUSIONS: Plasma time profiles after i.g. administration has a prolonged pharmacokinetics. Tissue distribution study showed potential side effects to the stomach due to a higher accumulation of HI-6 in this tissue after i.g. administration but not after a standard i.m. administration. Higher content of HI-6 in the kidneys after i.m. administration suggests the main way of the oxime elimination.
- MeSH
- oximy aplikace a dávkování farmakokinetika škodlivé účinky MeSH
- pyridinové sloučeniny aplikace a dávkování farmakokinetika škodlivé účinky MeSH
- reaktivátory cholinesterasy aplikace a dávkování farmakokinetika škodlivé účinky MeSH
- Sus scrofa krev metabolismus MeSH
- tkáňová distribuce MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
Krevní výron, jako důsledek intravitálního krvácení, je z forenzního hlediska považován za důležitou známku vitální reakce poranění. Ve zvláštních případech je však nutno připustit možnost, že hematom vznikl až postmortálně. Vznik supravitálních změn je zřejmý kupř. u dárců orgánů u nichž je po smrti mozku udržován krevní oběh a plicní ventilace. Posmrtný vznik krevních výronů ale pozorujeme i u dárců po enukleaci očních bulbů odebraných až před pitvou na Ústavu soudního lékařství a toxikologie; tyto krevní výrony se manifestují za několik hodin po odběru. Mimoto jsme ale zaznamenali vznik hematomu v očnici, který nebyl způsoben ani intravitálním ani postmortálním přímým násilím; jeho vznik nelze vysvětlit jinak než posmrtnou propagací výronu ze zlomeniny přední jámy lební do očnice. V dostupné literatuře jsme nezjistili údaj o posmrtném vzniku resp. přemístění hematomu takového rozsahu. Jde tedy, v rámci znalostí o supravitální reakci o poznatek obecného významu, ovšem i s forenzním dopadem. V konkrétním případě, dokumentace z místa činu umožnila korigovat posouzení mechanismu vzniku poranění resp. úrazového děje z hlediska podezření na cizí zavinění, které by v takovém případě přicházelo v úvahu (jako např. úder do očnice a pád pod projíždějící soupravu metra).
The hemorrhage as a result of intravital bleeding is considered, from forensic point of view, as important sign of vital reaction of injury. However, in special cases it must be accepted that hemorrhage occurred after the death. The formation of supravital changes is evident e.g. in organ donors whose blood circulation and pulmonary ventilation is kept after the brain death. The post-mortem origin of hemorrhages can also be seen in donors of eyeballs after enucleation made before the autopsy at Institute of Forensic Medicine and Toxicology. These hemorrhages are manifested after several hours when eyeballs were removed. Moreover, we observed the origin of hemorrhage in orbit which was caused nor by intravital bleeding neither by direct force. Its origin could not be explained nothing but postmortem propagation of the hemorrhage from the fracture of anterior fossa of the scull base. We did not find information about postmortem origin or relocation of hemorrhage of such extent in the literature. In the frame of knowledge about supravital reaction, this finding is of general importance with forensic impact. The documentation from the scene of death allowed correcting the appreciation of the mechanism of injury and traumatic process from the point of view of foreign culpability which should be considered in such case (e.g. a blow to the orbit with following fall under passing subway train).
- Klíčová slova
- forenzní význam, postmortální propagace hematomu, vitální a supravitální reakce,
- MeSH
- dospělí MeSH
- hematom diagnóza klasifikace MeSH
- kraniocerebrální traumata diagnóza klasifikace patologie MeSH
- lidé MeSH
- pitva metody MeSH
- polytrauma diagnóza klasifikace MeSH
- poranění elektrickým proudem diagnóza klasifikace MeSH
- posmrtné změny MeSH
- úrazy a nehody klasifikace MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
Understanding variation in resource specialization is important for progress on issues that include coevolution, community assembly, ecosystem processes, and the latitudinal gradient of species richness. Herbivorous insects are useful models for studying resource specialization, and the interaction between plants and herbivorous insects is one of the most common and consequential ecological associations on the planet. However, uncertainty persists regarding fundamental features of herbivore diet breadth, including its relationship to latitude and plant species richness. Here, we use a global dataset to investigate host range for over 7,500 insect herbivore species covering a wide taxonomic breadth and interacting with more than 2,000 species of plants in 165 families. We ask whether relatively specialized and generalized herbivores represent a dichotomy rather than a continuum from few to many host families and species attacked and whether diet breadth changes with increasing plant species richness toward the tropics. Across geographic regions and taxonomic subsets of the data, we find that the distribution of diet breadth is fit well by a discrete, truncated Pareto power law characterized by the predominance of specialized herbivores and a long, thin tail of more generalized species. Both the taxonomic and phylogenetic distributions of diet breadth shift globally with latitude, consistent with a higher frequency of specialized insects in tropical regions. We also find that more diverse lineages of plants support assemblages of relatively more specialized herbivores and that the global distribution of plant diversity contributes to but does not fully explain the latitudinal gradient in insect herbivore specialization.
- MeSH
- biodiverzita MeSH
- biologické modely MeSH
- býložravci fyziologie MeSH
- dieta * MeSH
- ekosystém MeSH
- fylogeneze MeSH
- hmyz klasifikace fyziologie MeSH
- hostitelská specificita MeSH
- Lepidoptera klasifikace fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
Reticulitermes, Heterotermes and Coptotermes form a small termite clade with partly overlapping distributions. Although native species occur across all continents, the factors influencing their distribution are poorly known. Here, we reconstructed the historical biogeography of these termites using mitochondrial genomes of species collected on six continents. Our analyses showed that Reticulitermes split from Heterotermes + Coptotermesat 59.5 Ma (49.9-69.5 Ma 95% CI), yet the oldest split within Reticulitermes(Eurasia and North America) is 16.1 Ma (13.4-19.5 Ma) and the oldest split within Heterotermes + Coptotermesis 36.0 Ma (33.9-40.5 Ma). We detected 14 disjunctions between biogeographical realms, all of which occurred within the last 34 Ma, not only after the break-up of Pangaea, but also with the continents in similar to current positions. Land dispersal over land bridges explained four disjunctions, oceanic dispersal by wood rafting explained eight disjunctions, and human introduction was the source of two recent disjunctions. These wood-eating termites, therefore, appear to have acquired their modern worldwide distribution through multiple dispersal processes, with oceanic dispersal and human introduction favoured by the ecological traits of nesting in wood and producing replacement reproductives.
- MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- genom hmyzu * MeSH
- genom mitochondriální * MeSH
- Isoptera genetika fyziologie MeSH
- rozšíření zvířat * MeSH
- sekvenční analýza DNA MeSH
- sekvenční seřazení MeSH
- zavlečené druhy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Deep evolutionary relationships within raptorial niche have recently been challenged. Little is known as to whether birds of the raptorial niche share congruent or host-switching communities of parasites. Here, we analyzed the helminth component communities associated with birds of prey and owls. From 1962 to 2015, we examined 1731 birds of prey and owls in Czechia, and we provide a meta-analysis based on the available literature. Both the analysis of newly examined birds as well as the meta-analysis of previous studies suggested low similarities in the helminth component communities in Strigiformes relative to those in Accipitriformes (Sørensen similarity indices 0.380 in Czechia and 0.324 worldwide) or Falconiformes (0.341 and 0.328), as well as low similarities in the helminth component communities in Falconiformes to those in Accipitriformes (0.366 and 0.413). Globally, 59.6% of helminth species found in Accipitriformes, 39.5% of those in Falconiformes and 38.3% of those in Strigiformes were obligate specialists that were limited to a single examined bird order. Another 11.5%, 12.8% and 8.3% of species had core hosts in only a single order. Only five helminth species infected all three bird orders at a similar prevalence. The differences in prevalence cannot be explained by differences in food composition. We provide detailed information on the prevalence, seasonality, age- and sex-specificity, intensity and lethality of helminth infections. In conclusion, we provide the first systematically collected evidence on the congruence of the helminth distribution and phylogeny of the raptorial niche, which is consistent with its split into Australaves and Afroaves.
- MeSH
- cizopasní červi klasifikace fyziologie MeSH
- dravci parazitologie MeSH
- Falconiformes parazitologie MeSH
- fylogeneze MeSH
- helmintózy zvířat epidemiologie MeSH
- nemoci ptáků epidemiologie parazitologie MeSH
- prevalence MeSH
- roční období MeSH
- rozšíření zvířat * MeSH
- sexuální faktory MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- metaanalýza MeSH
- Geografické názvy
- Česká republika MeSH
