Quantitative data are presented on the spatial distribution of metacercariae of the digenean trematode Diploslomum phoxini (Faust, 1918) in the brains of minnows, Phoxinus phoxinus (Linnaeus, 1758), from two Scottish populations. Sequential examination of serial histological sections revealed metacercariae to be unevenly distributed throughout the brain, aggregating in specific regions including the cerebellum, the medulla oblongata and the optic lobes. In addition, a number of metacercariae were found in the anterior part of the spinal cord. The inferior lobe of the cerebellum, pituitary, olfactory lobes and olfactory bulbs were largely free of metacercariae. Reasons for the uneven distribution of metacercariae within the brains of infected minnows are discussed, including the possibility that the parasite may have evolved to enhance its transmission to subsequent hosts by aggregating in regions known to be important in the control of the host’s antipredator responses.
This paper questions the uncritical transfer of neoliberal concepts, such as financialisation and overreliance on conceptual dichotomies like formal/informal, as the lenses through which to understand practices of housing provision and consumption in the post-communist space. To this end, it introduces the newly-established ‘diverse economies’ framework, which has been used elsewhere to reveal existing and possible alternatives to advanced capitalism. Applied to the Romanian case, the lens of diverse economic practices helps shed light on the ways in which the current housing system was historically constituted, with implications for how housing consumption is now stratified across some related housing typologies. The paper invites debate on the theoretical usefulness of the diverse economies framework to study housing phenomena, particularly its implications for understanding patterns of inequality and poverty, its potential to devise useful analytical categories, and its effect of directing attention to acts of resistance to neoliberal capitalism.
Food webs are of crucial importance for understanding any ecosystem. The accuracy of food web and ecosystem models rests on the reliability of the information on the feeding habits of the species involved. Water boatmen (Corixoidea) is the most diverse superfamily of water bugs (Heteroptera: Nepomorpha), frequently the most abundant group of insects in a variety of freshwater habitats worldwide. In spite of their high biomass, the importance of water boatmen in aquatic ecosystems is frequently underestimated. The diet and feeding habits of Corixoidea are unclear as published data are frequently contradictory. We summarise information on the feeding habits of this taxon, which exemplify the difficulties in evaluating published data on feeding habits in an invertebrate taxon. It is concluded that Corixoidea are, unlike other true bugs, capable of digesting solid food, but their feeding habits are still insufficiently known. The dominant feeding strategy in this taxon is zoophagy, but several species consume other foods, particularly algae and detritus. Only members of the subfamily Cymatiainae seem to be exclusively predators. In other subfamilies, the diet of different species and different sexes or populations of a single species may vary depending on the food available or is still unknown. We conclude, that a multi-method approach is needed to elucidate the feeding habits of aquatic insects and invertebrates in general., Christian W. Hädicke, Dávid Rédei, Petr Kment., and Obsahuje bibliografii
This study determined the scale of the phoresy of mesostigmatid mite by Ips typographus. Thirty pheromone traps in the Karkonosze National Park (Poland) caught 10,575 bark beetles on which there were 2,388 mesostigmatid mites belonging to eight species. The most numerous mites were Dendrolaelaps quadrisetus (1076 ind.) and Trichouropoda polytricha (1067 ind.). and Dariusz J. Gwiazdowicz, Jacek Kamczyc, Jerzy Bloszyk.
We establish the Doob inequality for martingale difference arrays and provide a sufficient condition so that the strong law of large numbers would hold for an arbitrary array of random elements without imposing any geometric condition on the Banach space. Some corollaries are derived from the main results, they are more general than some well-known ones.
Honey bees are not only important for honey production but also as pollinators of wild and cultivated plants. The Eastern honeybee (Apis cerana) is more resistant to several pathogens than the Western honeybee (Apis mellifera), and the genomes of two strains of the nominotypical subspecies, A. cerana cerana, northern (Korea) and southern (China) strains, have been sequenced. Apis cerana japonica, another subspecies of A. cerana, shows many specific features (e.g. mildness, low honey production and frequently absconds) and it is important to study the molecular biological and genetic aspects of these features. To accelerate the genetic research on A. cerana japonica, we sequenced the genome of this subspecies. The draft genome sequence of A. cerana japonica presented here is of high quality in terms of basic genome status (e.g. N50 is 180 kbp, total length is 211 Mbp, and largest contig length is 1.31 Mbp) and BUSCO results. The gene set of A. cerana japonica was predicted using AUGUSTUS software and the set of genes was annotated using Blastp and InterProScan, and GO terms were added to each gene. The number of genes is higher than in A. mellifera and in the two strains of A. cerana cerana sequenced previously. A small number of transposable elements and repetitive regions were found in A. cerana japonica, which are also in the genomes of A. mellifera and the northern and southern strains of A. cerana cerana. Apis cerana is resistant to several pathogens that seriously damage A. mellifera. We searched for 41 orthologs related to the IMD and Toll pathways, which have key roles in the immune reaction to invading pathogens. Some orthologs were not identified in the genome of the northern strain of A. cerana cerana. This indicates that the Toll and IMD pathways function in the same way as in A. mellifera and Drosophila melanogaster., Kakeru Yokoi, Hironobu Uchiyama, Takeshi Wakamiya, Mikio Yoshiyama, Jun-Ichi Takahashi, Tetsuro Nomura, Tsutomu Furukawa, Shunsuke Yajima, Kiyoshi Kimura., and Obsahuje bibliografii
We studied visual orientation and perching behaviour of a territorial libellulid dragonfly species, Libellula quadrimaculata. The studies were performed during sunny, cloudless conditions at a pond in southern Styria, Austria, from May to July of 2001 and 2002. Individual males were observed for periods of 3 to 4 weeks.
We measured dragonfly's horizontal orientation relative to the solar azimuth, and vertical orientation relative to the solar altitude. The measurements indicated that the males had a favourable view of the sky during perching. In addition, the relative amounts of ultraviolet (UV) and blue-violet radiation in scattered light (not direct sunlight) were calculated for the whole sky and for the section of the sky viewed by the fovea. Our results show that the dorsal fovea is directed preferentially toward a section of the sky away from the sun, with less radiation but a higher UV and blue-violet saturation.
The present findings fit in well with the hypothesis, based on optical and physiological data, that the fovea, which is sensitive only to blue and UV radiation, is optimally suited to the detection of small, rapidly flying insects against the blue sky. The findings supply the first behavioural correlates of this foveal specialisation.
Throughout this abstract, $G$ is a topological Abelian group and $\widehat{G}$ is the space of continuous homomorphisms from $G$ into the circle group $\mathbb{T}$ in the compact-open topology. A dense subgroup $D$ of $G$ is said to determine $G$ if the (necessarily continuous) surjective isomorphism $\widehat{G}\twoheadrightarrow \widehat{D}$ given by $h\mapsto h\big |D$ is a homeomorphism, and $G$ is determined if each dense subgroup of $G$ determines $G$. The principal result in this area, obtained independently by L. Außenhofer and M. J. Chasco, is the following: Every metrizable group is determined. The authors offer several related results, including these. 1. There are (many) nonmetrizable, noncompact, determined groups. 2. If the dense subgroup $D_i$ determines $G_i$ with $G_i$ compact, then $\oplus _iD_i$ determines $\Pi _i G_i$. In particular, if each $G_i$ is compact then $\oplus _i G_i$ determines $\Pi _i G_i$. 3. Let $G$ be a locally bounded group and let $G^+$ denote $G$ with its Bohr topology. Then $G$ is determined if and only if ${G^+}$ is determined. 4. Let $\mathop {\mathrm non}({\mathcal N})$ be the least cardinal $\kappa $ such that some $X \subseteq {\mathbb{T}}$ of cardinality $\kappa $ has positive outer measure. No compact $G$ with $w(G)\ge \mathop {\mathrm non}({\mathcal N})$ is determined; thus if $\mathop {\mathrm non}({\mathcal N})=\aleph _1$ (in particular if CH holds), an infinite compact group $G$ is determined if and only if $w(G)=\omega $. Question. Is there in ZFC a cardinal $\kappa $ such that a compact group $G$ is determined if and only if $w(G)<\kappa $? Is $\kappa =\mathop {\mathrm non}({\mathcal N})$? $\kappa =\aleph _1$?
In the paper, we show that the space of functions of bounded variation and the space of regulated functions are, in some sense, the dual space of each other, involving the Henstock-Kurzweil-Stieltjes integral.
In this paper, we propose a new impulsive predator prey model with impulsive control at different fixed moments and analyze its interesting dynamic behaviors. Sufficient conditions for the globally asymptotical stability of the semi-trivial periodic solution and the permanence of the present model are obtained by Floquet theory of impulsive differential equation and small amplitude perturbation skills. Existences of the "infection-free" periodic solution and the "predator-free" solution are analyzed by bifurcation theory of impulsive differential equation. Finally, the analytical results presented in the work are validated by numerical simulation figures for this proposed model.