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474272. The draft genome sequence of the Japanese honey bee, Apis cerana japonica (Hymenoptera: Apidae)
- Creator:
- Yokoi, Kakeru, Uchiyama, Hironobu, Wakamiya, Takeshi, Yoshiyama, Mikio, Takahashi, Jun-Ichi, Nomura, Tetsuro, Furukawa, Tsutomu, Yajima, Shunsuke, and Kimura, Kiyoshi
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, včelovití, Hymenoptera, Apidae, Apis cerana japonica, genome sequence, transposable elements, innate immune genes, 2, and 59
- Language:
- English
- Description:
- 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
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474273. The dragonfly Libellula quadrimaculata (Odonata: Libellulidae) makes optimal use of the dorsal fovea of the compound eyes during perching
- Creator:
- Sauseng, Manuela, Pabst, Maria-Anna, and Kral, Karl
- Type:
- article, model:article, and TEXT
- Subject:
- Odonates, perching, compound eye, dorsal fovea, vision, and visual ecology
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474274. The dual group of a dense subgroup
- Creator:
- Comfort;, William Wistar , Raczkowski, S. U. , and Trigos-Arrieta, F. Javier
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Bohr compactification, Bohr topology, character, character group, Außenhofer-Chasco Theorem, compact-open topology, dense subgroup, determined group, duality, metrizable group, reflexive group, and reflective group
- Language:
- English
- Description:
- 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 $\kappa =\mathop {\mathrm non}({\mathcal N})$? $\kappa =\aleph _1$?
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474275. The dual of the space of functions of bounded variation
- Creator:
- Aye, Khaing Khaing and Lee, Peng Yee
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bounded variation, two-norm space, dual space, linear functional, Henstock integral, Stieltjes integral, and regulated function
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474276. The dynamic behaviors of a new impulsive predator prey model with impulsive control at different fixed moments
- Creator:
- Wang, Linjun, Xie, Youxiang, and Deng, Qicheng
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- impulsive differential equation, bifurcation theory, stability, impulsive control, and persistence and extinction
- Language:
- English
- Description:
- 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.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474277. The dynamics of the zodiacal dust cloud on account of optical and infrared observations
- Creator:
- Kneißel, B. and Giese, R. H.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- optical and infrared observations, zodiacal dust cloud, and collisions
- Language:
- Czech
- Description:
- The method to determine the inclination distribution of zodiacal particle orbits according to 3D-density models of zodiacal dust presented by Giese and Kneißel (1987, this volume) is briefly discussed. The results show that models with additional bulges at the solar poles bear an isotropic component of the inclination distribution amounting up to 20% of all orbits, whereas infrared models show almost no isotropic component. The existence of an isotropic component for zodiacal dust orbits is questioned by comparison with the orbital elements of meteoroidal particles which serve as a source for the zodiacal dust by mutual collisions
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474278. The dynamics of weakly interacting fronts in an adsorbate-induced phase transition model
- Creator:
- Ei, Shin-Ichiro and Tsujikawa, Tohru
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- reaction-diffusion system, iteraction of fronts, and phase transition model
- Language:
- English
- Description:
- Hildebrand et al. (1999) proposed an adsorbate-induced phase transition model. For this model, Takei et al. (2005) found several stationary and evolutionary patterns by numerical simulations. Due to bistability of the system, there appears a phase separation phenomenon and an interface separating these phases. In this paper, we introduce the equation describing the motion of two interfaces in R2 and discuss an application. Moreover, we prove the existence of the traveling front solution which approximates the shape of the solution in the neighborhood of the interface.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474279. The earliest fossil flower bugs (Heteroptera: Cimicomorpha: Cimicoidea: Vetanthocoridae) from the Middle Jurassic of Inner Mongolia, China
- Creator:
- Hou, Wenjing, Yao, Yunzhi, Zhang, Weiting, and Ren, Dong
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Heteroptera, Vetanthocoridae, fossil, Middle Jurassic, Inner Mongolia, 2, and 59
- Language:
- English
- Description:
- One new genus with two new fossil species, Pumilanthocoris gracilis gen. n. sp. n. and P. obesus gen. n. sp. n., which were found in the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China, are described and illustrated. These are the earliest fossil records of Vetanthocoridae., Wejing Hou ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474280. The early iron metallurgy in the Siberian Arctic
- Creator:
- Vodyasov, Evgeny
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Circumpolar Region, Siberia, iron smelting, Early Iron Age, polární oblast, Sibiř, výroba železa, and starší doba železná
- Language:
- Czech
- Description:
- Archaeological excavations conducted at the settlement-sanctuary of Ust-Polui, located just north of the Arctic Circle in Western Siberia yielded the oldest remains of early iron production in the Circumpolar region of Asia. Ust-Polui archaeological finds associated with metallurgy of iron are dated back to the 3rd century BC – 2nd century AD. Hence the finds date the origins of metallurgical technologies used in the north of Western Siberia virtually several centuries back in time and geographically extend the spread of iron metallurgy between the eras significantly. It seems that Ust-Polui is the most northern point on the Earth where iron metallurgy was developed by ancient people. The discovery of new iron production site poses an important question – what are the reasons and ways of appearance of the iron smelting technologies in the Polar North of Siberia? It is possible that all knowledge was obtained from outside via contacts with metal producing societies, who lived in the eastern regions of the Ural Mountains (to the southwest of Ust-Polui), and knew how to produce iron about two thousand years ago. and Archeologické výzkumy osady-svatyně Ust-Polui, nacházející se severně od arktického kruhu v západní Sibiři, odkryly nejstarší pozůstatky rané výroby železa v polárních oblastech Asie. Archeologické nálezy spojené s metalurgií železa jsou datovány od 3. stol. př. n. l. do 2. stol. n. l. Datují tak počátky užívání metalurgických technologií v severozápadní Sibiři prakticky o několik století dříve a geograficky výrazně rozšiřují prostor, v němž se železná metalurgie mezi danými obdobími šířila. Zdá se, že Ust-Polui je nejsevernějším bodem planety, kde byla starověká metalurgie železa rozvinuta. S objevem nové lokality s doklady metalurgie železa vyvstává důležitá otázka – z jakých důvodů a jakým způsobem se metalurgie železa za polárním kruhem na severu Sibiře objevila? Je možné, že veškeré poznání bylo získáno zvenčí prostřednictvím kontaktů se společnostmi vyrábějícími kovy, které žily ve východních oblastech Uralských hor (na jihozápad od Ust-Polui) a které si osvojily znalost výroby železa již před dvěma tisíci lety.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public