Those who argue that dispositional explanations are genuine explanations usually construe them as causal explanations. There are several well-known arguments against the causal efficacy of dispositions, but there are as well demonstrations that on some minimal conditions, dispositions could be viewed as causally relevant to the effects which they are taken to explain. Although the latter position is generally tenable, it may be shown that in some important cases it is not a good idea to commit to a causal construal of dispositional explanations. The argument goes as follows: (1) Dispositional explanations are valued for certain specific extra-inferences which they allow us to draw; (2) The causal construal of dispositional explanations can account for some of these extra-inferences only on the assumption that the disposition is a common cause of its manifestations; (3) However, under certain circumstances, the common cause assumption is refuted on theoretical or empirical grounds; Therefore, (4) under certain circumstances, the causal construal of dispositional explanations cannot account for what these explanations are valued for. The latter conclusion is a reason to argue that in some cases at least, the causal construal of dispositional explanations should be avoided., Ti, kteří tvrdí, že dispoziční vysvětlení jsou skutečná vysvětlení, je obvykle považují za kauzální vysvětlení. Existuje několik dobře známých argumentů proti kauzální účinnosti dispozic, ale jsou zde také demonstrace, že za určitých minimálních podmínek lze dispozice považovat za kauzálně relevantní vzhledem k účinkům, které mají být vysvětleny. I když je tato pozice obecně udržitelná, může být prokázáno, že v některých důležitých případech není dobré zavázat se k příčinnému konstruktivnímu vysvětlení. Argument jde následovně: (1) Dispoziční vysvětlení jsou oceňována pro určité specifické extra-závěry, které nám umožňují kreslit; (2) Kauzální konstrukční dispoziční vysvětlení může vysvětlit některé z těchto extra-dedukcí pouze za předpokladu, že dispozice je společnou příčinou jejích projevů; (3) Za určitých okolností je však předpoklad společné příčiny vyvrácen z teoretických nebo empirických důvodů; Proto (4) za určitých okolností nemůže kauzální konstrukční vysvětlení vysvětlení vysvětlit, za co jsou tato vysvětlení oceňována. Tento závěr je důvodem pro tvrzení, že v některých případech je třeba se vyhnout kauzálnímu konstrukčnímu vykládání vysvětlení. kauzální konstruktivní vysvětlení nemůže vysvětlit, za co jsou tato vysvětlení oceňována. Tento závěr je důvodem pro tvrzení, že v některých případech je třeba se vyhnout kauzálnímu konstrukčnímu vykládání vysvětlení. kauzální konstruktivní vysvětlení nemůže vysvětlit, za co jsou tato vysvětlení oceňována. Tento závěr je důvodem pro tvrzení, že v některých případech je třeba se vyhnout kauzálnímu konstrukčnímu vykládání vysvětlení., and Lilia Gurova
Arostrilepis beringiensis (Kontrimavichus et Smirnova, 1991) is redescribed on the basis of its type specimens from Lemmus trimucronatus (Richardson) and material from the collections of the Institute of Systematics and Ecology of Animals, Novosibirsk from the lemmings Myopus schisticolor (Lilljeborg) and Lemmus sibiricus (Kerr) from the Asian part of Russia. Specimens previously identified as Arostrilepis horrida (Linstow, 1901) from voles are revised and newly collected materials are addressed. Two new species of the genus Arostrilepis Mas-Coma et Tenora, 1997, A. intermedia sp. n. from red-backed voles (Myodes Pallas) from the Asian part of Russia and A. janickii sp. n. from Europe, are described. These species are clearly distinguished from congeners by form and size of the cirrus and its armature as well as the type of arrangement for the testes, position of the cirrus-sac with regard to poral ventral osmoregulatory canals, and host specificity.
The type species of the cestode genus Arostrilepis Mas-Coma et Tenora, 1997, Arostrilepis horrida (Linstow, 1901), is redescribed on the basis of the syntype material from the brown rat (Rattus norvegicus) deposited in the collection of the Museum für Naturkunde, Berlin. Arostrilepis horrida (sensu lato), reported from a wide range of rodents throughout the Holarctic Region, is shown to be a species complex. The proposed host range and geographical distribution of A. horrida (sensu stricto) are limited to the data reported in the original description. The previously proposed synonymy of A. horrida is examined and the following species are excluded from the list of its synonyms: Hymenolepis procera Janicki, 1904, H. arvicolina Cholodkowsky, 1913, H. sciurina Cholodkowsky, 1913 and H. mathevossianae Akhumyan, 1946; these are considered species inquirendae. Specimens previously identified as A. horrida from voles from the Asian part of Russia are revised and newly collected materials are worked out. Two new species, A. macrocirrosa sp. n. and A. tenuicirrosa sp. n., are described. The main differentiating characters used to distinguish Arostrilepis spp. are the form and size of cirrus and its armature as well as the type of arrangement for the testes. The new species can also be distinguished from one another on the basis of sequences of the ITS2 rRNA gene. The generic diagnosis of Arostrilepis is emended. Hymenolepis neurotrichi Rausch, 1962, which had been placed in Arostrilepis by Mas-Coma and Tenora (1997), does not correspond to the generic diagnosis and is considered a species incertae sedis.
Blood films were examined from 154 wild and captive tortoises from four provinces of South Africa, including Gauteng, Kwazulu-Natal, North West and Western Cape. The five species of chelonians studied were Chersina angulata (Schweigger), Kinixys belliana belliana (Gray), K. lobatsiana Power, K. natalensis Hewitt, and Stigmochelys pardalis (Bell). Two species of haemogregarines, previously reported from Mozambique, were identified in blood films, namely Haemogregarina fitzsimonsi Dias, 1953 and Haemogregarina parvula Dias, 1953. Additional stages of development (trophozoites and probable meronts, merozoites and immature gamonts) in blood preparations from South Africa warranted the redescription of H. fitzsimonsi. A variety of hosts and broad host distribution range were observed for this haemogregarine, with all five species of tortoises parasitized, wild and captive, from all four provinces, in all seasons. In contrast, only two individuals of K. b. belliana and one S. pardalis, all three captive in Kwazulu-Natal, contained H. parvula with encapsulated stages resembling those of Hemolivia mauritanica (Sergent et Sergent, 1904). For H. fitzsimonsi, parasite prevalences, but not parasitaemias, were significantly higher in captive than wild S. pardalis; captive female S. pardalis also showed a significantly greater prevalence of infection than males, but younger, lighter hosts were not significantly more heavily parasitized than older, heavier individuals. The ticks, Amblyomma marmoreum Koch, 1844 and A. sylvaticum (De Geer, 1778), found attached to some tortoises, may prove to be definitive hosts for the two species of haemogregarines observed.
Pseudocharopinus Kabata, 1964 is one of the 48 genera comprising the Lernaeopodidae (Copepoda, Siphonostomatoida). Currently there are 11 accepted species contained in Pseudocharopinus. Pseudocharopinus pteromylaei Raibaut et Essafi, 1979 infects the spiracles and gill filaments of Pteromylaeus bovinus (Geoffroy St. Hilaire) and is most similar in general appearance to P. pteroplateae (Yamaguti et Yamasu, 1959) from which it clearly differs in the size and dimensions of the dorsal shield and the posterior processes. Additional features of the antenna and the maxilliped of P. pteromylaei, not previously illustrated, are discussed and illustrated while more detailed illustrations of other appendages are provided. This is the first report of the occurrence of a Pseudocharopinus species from the west Indian Ocean and the first report of P. pteromylaei off the east coast of South Africa.
The adults of Trichosurolaelaps dixous Domrow, 1972 are redescribed from a population of Trichosurus cunninghami Lindenmayer, Dubach et Viggers, 2002 in south-eastern Australia. The nymphal stages are described for the first time. Morphologically, T. dixous is similar to Trichosurolaelaps crassipes Womersley, 1956. Morphological differences between the pre-female deutonymphs and adult females of the two mite species are the presence of a single large ventral spur on tibia I of T. dixous. Males of T. dixous could not be distinguished from T. crassipes morphologically and the idiosomal length of male T. dixous was variable (475-683 μm). Protonymphs of the two mite species differed only in size, with that of T. dixous being larger. Although T. crassipes was prevalent in a sympatric population of Trichosurus vulpecula and has been reported from other populations of T. cunninghami in southern Australia, it was never recovered from the population of T. cunninghami studied.
We have computed the following physical parameters for the atmosphere of Titan, usinge Voyager´s measurements:
1) Temperature, 2) Pressure, 3) Density, 4 Speed of sound, 5) Density scale, 6) Number density, 7) Mean free path, 8) Viscosity, 9) Pressure scale, 10) Mean particle velocity, 11) Mean collisional frequency, 12) Columnar mass.
In this article we produce a refined version of the classical Pohozaev identity in the radial setting. The refined identity is then compared to the original, and possible applications are discussed.
This paper analyses the bivariate relationship between flood peaks and corresponding flood event volumes modelled by empirical and theoretical copulas in a regional context, with a focus on flood generation processes in general, the regional differentiation of these and the effect of the sample size on reliable discrimination among models. A total of 72 catchments in North-West of Austria are analysed for the period 1976-2007. From the hourly runoff data set, 25 697 flood events were isolated and assigned to one of three flood process types: synoptic floods (including long- and short-rain floods), flash floods or snowmelt floods (both rain-on-snow and snowmelt floods). The first step of the analysis examines whether the empirical peak-volume copulas of different flood process types are regionally statistically distinguishable, separately for each catchment and the role of the sample size on the strength of the statements. The results indicate that the empirical copulas of flash floods tend to be different from those of the synoptic and snowmelt floods. The second step examines how similar are the empirical flood peak-volume copulas between catchments for a given flood type across the region. Empirical copulas of synoptic floods are the least similar between the catchments, however with the decrease of the sample size the difference between the performances of the process types becomes small. The third step examines the goodness-of-fit of different commonly used copula types to the data samples that represent the annual maxima of flood peaks and the respective volumes both regardless of flood generating processes (the traditional engineering approach) and also considering the three process-based classes. Extreme value copulas (Galambos, Gumbel and Hüsler-Reiss) show the best performance both for synoptic and flash floods, while the Frank copula shows the best performance for snowmelt floods. It is concluded that there is merit in treating flood types separately when analysing and estimating flood peak-volume dependence copulas; however, even the enlarged dataset gained by the process-based analysis in this study does not give sufficient information for a reliable model choice for multivariate statistical analysis of flood peaks and volumes.
Spermiogenesis in the amphilinidean cestode Amphilina foliacea (Rudolphi, 1819) was examined using transmission electron microscopy. The orthogonal development of the two flagella is followed by a flagellar rotation and their proximodistal fusion with the median cytoplasmic process. This process is accompanied by extension of both the mitochondrion and nucleus into the median cytoplasmic process. The two pairs of electron-dense attachment zones mark the lines where the proximodistal fusion of the median cytoplasmic process with the two flagella takes place. The intercentriolar body, previously undetermined in A. foliacea, is composed of three electron-dense and two electron-lucent plates. Also new for this species is the finding of electron-dense material in the apical region of the differentiation zone at the early stage of spermiogenesis, and the fact that two arching membranes appear at the base of the differentiation zone only when the two flagella rotate towards the median cytoplasmic process. The present data add more evidence for a close relationship between the Amphilinidea and the Eucestoda.