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3172. Compact embeddings of Besov spaces involving only slowly varying smoothness
- Creator:
- Caetano, Antonio, Gogatishvili, Amiran, and Opic, Bohumír
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Besov spaces with generalized smoothness, Lorentz-Karamata spaces, and compact embeddings
- Language:
- English
- Description:
- We characterize compact embeddings of Besov spaces $B^{0,b}_{p,r}(\mathbb {R}^n)$ involving the zero classical smoothness and a slowly varying smoothness $b$ into Lorentz-Karamata spaces $L_{p, q; \bar {b}}(\Omega )$, where $\Omega $ is a bounded domain in $\mathbb {R}^n$ and $\bar {b}$ is another slowly varying function.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3173. Compact images of spaces with a weaker metric topology
- Creator:
- Yan, Peng-Fei and Lü, Cheng
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- sequence-covering mappings, sequentially-quotient mappings, compact mappings, and weaker metric topology
- Language:
- English
- Description:
- If $X$ is a space that can be mapped onto a metric space by a one-to-one mapping, then $X$ is said to have a weaker metric topology. \endgraf In this paper, we give characterizations of sequence-covering compact images and sequentially-quotient compact images of spaces with a weaker metric topology. The main results are that \endgraf (1) $Y$ is a sequence-covering compact image of a space with a weaker metric topology if and only if $Y$ has a sequence $\{\mathcal F_i\}_{i\in \mathbb N}$ of point-finite $cs$-covers such that $ {\bigcap _{i\in \mathbb N}}\mathop{\rm st} (y,\mathcal F_i)=\{y\}$ for each $y\in Y$. \endgraf (2) $Y$ is a sequentially-quotient compact image of a space with a weaker metric topology if and only if $Y$ has a sequence $\{\mathcal F_i\}_{i\in \mathbb N}$ of point-finite $cs^*$-covers such that ${\bigcap _{i\in \mathbb N}}\mathop{\rm st} (y,\mathcal F_i)=\{y\}$ for each $y\in Y$.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3174. Comparative analysis of maternal and grand-maternal photoperiodic responses of Trichogramma species (Hymenoptera: Trichogrammatidae)
- Creator:
- Voinovich, Natalia D., Vaghina, Nina P., and Reznik, Sergey Ya.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Trichogrammatidae, Trichogramma, diapause, photoperiod, temperature, maternal effect, grand-maternal effect, comulative photoperiodic effect, 2, and 59
- Language:
- English
- Description:
- 1_Maternal and grand-maternal photoperiodic responses of Trichogramma buesi, T. embryophagum, T. evanescens, T. piceum, T. principium, and T. telengai were investigated in laboratory conditions. During the experiment, grand-maternal and maternal generations developed at 20°C and one of the 4 photoperiodic regimes: L : D = 12 : 12, 14 : 10, 16 : 8, and 18 : 6 (in total, 16 combinations) while the progeny developed at L : D = 12 : 12 and one of the 3 thermal regimes: 13, 14, and 15°C. The proportion of diapausing individuals in the progeny of all the studied species was significantly dependent on the direct influence of temperature and on the maternal photoperiodic response. The influence of the photoperiodic conditions during development of the grand-maternal generation was statistically significant in 5 of the 6 studied species, being relatively weak in T. embryophagum and T. telengai, whose geographical ranges extend up to north-western regions of Europe (possibly, these wasps enter diapause so early that the grand-mothers of the diapausing generation develop under long day conditions). Comparative analysis showed that the thresholds of the maternal and grand-maternal photoperiodic responses coincided or almost coincided. The grand-maternal effect was stronger in the progeny of maternal females which developed under short day conditions than in those that developed under long day conditions. This pattern of interaction probably synchronizes the life cycle with seasonal changes because diapause is induced under decreasing day length and thus mothers of diapausing individuals develop at shorter daylength than do grand-mothers., 2_We conclude that the grand-maternal and the maternal effects on Trichogramma progeny diapause are based on one and the same photoperiodic response. In nature, the grand-maternal effect increases the proportion of diapausing individuals in the progeny of females which have developed under short day conditions during two generations, thus achieving a "cumulative" photoperiodic effect., Natalia D. Voinovich, Nina P. Vaghina, Sergey Ya. Reznik., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3175. Comparative analysis of quality metrics for community detection in social networks using genetic algorithm
- Creator:
- Kaur, S., Singh, S., Kaushal, S., and Sangaiah, A. K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- community detection, social network, optimization, objective function, genetic algorithm, and Néormalized mutual information
- Language:
- English
- Description:
- Web 2.0 has led to the expansion and evolution of web-based communities that enable people to share information and communicate on shared platforms. The inclination of individuals towards other individuals of similar choices, decisions and preferences to get related in a social network prompts the development of groups or communities. The identification of community structure is one of the most challenging task that has received a lot of attention from the researchers. Network community structure detection can be expressed as an optimisation problem. The objective function selected captures the instinct of a community as a group of nodes in which intra-group connections are much denser than inter-group connections. However, this problem often cannot be well solved by traditional optimisation methods due to the inherent complexity of network structure. Therefore, evolutionary algorithms have been embraced to deal with community detection problem. Many objective functions have been proposed to capture the notion of quality of a network community. In this paper, we assessed the performance of four important objective functions namely Modularity, Modularity Density, Community Score and Community Fitness on real-world benchmark networks, using Genetic Algorithm (GA). The performance measure taken to assess the quality of partitions is NMI (Normalized mutual information). From the experimental results, we found that the communities' identified by these objectives have different characteristics and modularity density outperformed the other three objective functions by uncovering the true community structure of the networks. The experimental results provide a direction to researchers on choosing an objective function to measure the quality of community structure in various domains like social networks, biological networks, information and technological networks.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3176. Comparative analysis of the location of rDNA in the Palaearctic bushcricket genus Isophya (Orthoptera: Tettigoniidae: Phaneropterinae)
- Creator:
- Grzywacz, Beata, Maryańska-Nadachowska, Anna, Chobanov, Dragan P., Karamysheva, Tatjana, and Warchałowska-Śliwa, Elżbieta
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Orthoptera, FISH, Ag-NOR, rDNA, telomeric repeats, 2, and 59
- Language:
- English
- Description:
- The present study focused on the evolution of the karyotype in 21 taxa of the genus Isophya, which was done by mapping the location on the chromosomes of ribosomal RNA (rRNA) coding genes using fluorescence in situ hybridization (FISH) with an 18S rDNA probe and using silver staining (AgNO3) to evaluate the activity of major rDNA clusters. Since the chromosome number and sex determination do not vary in this genus, the above markers were used in a detailed comparison of the cytogenetic features of species of Isophya. The species analyzed were placed into three groups based on the location of rDNA on their chromosomes: (1) rDNA-FISH signals only on the two long pairs of autosomes, (2) rDNA-FISH signals on one long and one short pair of autosomes, and (3) rDNA-FISH signals on three to five different sized pairs of autosomes. These groupings partly correspond to the morphological groupings proposed in earlier studies. One long pair of autosomes frequently carried rDNA in all the Isophya species and probably is a plesiomorphic character for these taxa. The cytogenetic mapping revealed great variability among Isophya species in the chromosomal location of major rDNA clusters. Our results suggest that the observed variation in the number of rDNA clusters can be an important species-group specific phylogenetic marker. Analysis of 18S rDNA hybridization signals showed that the evolutionary dynamics of rDNA in this genus is remarkably high and accompanied by changes in the structure of chromosomes bearing rDNA at an inter- and intra-specific level. The telomeric sequence (TTAGG)n hybridized with the termini of most of chromosomes, however, some chromosome ends lacked signals probably due to a low copy number of telomeric repeats. and Beata Grzywacz, Anna Maryańska-Nadachowska, Dragan P. Chobanov, Tatjana Karamysheva, Elżbieta Warchałowska-Śliwa.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3177. Comparative analysis of the testes and spermatogenesis in species of the family Pentatomidae (Heteroptera)
- Creator:
- de Souza, Hederson Vinícius, Murakami, Aline Sumitani, de Moura, Juliana, de Almeida, Elisângela Cristiane, Marques, Inaiá Fernandes Gallego, and Itoyama, Mary Massumi
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Pentatomidae, harlequin lobe, meiosis, spermatogenesis, spermiogenesis, 2, and 59
- Language:
- English
- Description:
- a1_There are few studies on the morphology and meiosis in the testicles of Heteroptera, but are extremely important, especially for the family Pentatomidae, because in some species in this family meiosis in the testicular lobes results in the production of non-fertile spermatozoa. With the aim of improving the level of understanding of this phenomenon the morphology of the testes and spermatogenesis in 10 species of Pentatomidae were recorded and compared. All of them have testes covered by a pigmented peritoneal sheath. In some species the internal membrane or just inside the peritoneal sheath is pigmented. The pigmentation of both membranes varied. The pigmentation of both was either yellow, or the internal membrane was yellowish and the external one reddish. When the membrane is pigmented, the colour is red or yellow. The number of lobes varied from 3 to 7, with intermediate numbers of 4 and 6. The size and diameter of the lobes are similar in all the species studied, except Proxys albopunculatus, in which the diameter of the third and fifth is smaller than that of the other lobes. The behaviour of the cells during spermatogenesis was the same in all lobes of most species, except in P. albopunctulatus, in which the harlequin lobe is absent and the cells in lobes 4 and 6 exhibited characteristics different from those of cells in lobes 1-3 and 5. Chlorocoris complanatus and Loxa deducta (both Pentatominae) have a harlequin lobe (lobe 5). The chromosome complements recorded were: 2n = 12 (10A + XY) in Dichelops melacanthus and Edessa collaris, 2n = 14 (12A + XY) in C. complanatus, Edessa meditabunda, Ladeaschistus sp., Loxa deducta, P. albopunctulatus, Piezodorus guildinii and Thyanta perditor and 2n = 16 (14A + XY) in Edessa affinis. Thus, this study extends the knowledge of characteristics, such as the pigmentation of the peritoneal sheath, number of testicular lobes, the occurrence of meiotic cells in some, a2_testicular lobes, and the chromosome complements of the family Pentatomidae., and Hederson Vinícius De Souza, Aline Sumitani Murakami, Juliana De Moura, Elisângela Cristiane De Almeida, Inaiá Fernandes Gallego Marques, Mary Massumi Itoyama.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3178. Comparative behavioral and EAG responses of female obliquebanded and redbanded leafroller moths (Lepidoptera: Tortricidae) to their sex pheromone components
- Creator:
- Gökce, Ayhan, Stelinski, Lukasz L., Gut, Larry J., and Whalon, Mark E.
- Type:
- article, model:article, and TEXT
- Subject:
- Tortricidae, obliquebanded leafroller, Choristoneura rosaceana, redbanded leafroller, Argyrotaenia velutinana, electroantennogram recording, sex-attractant pheromone, female response, autodetection, calling behaviour, oviposition, and mating disruption
- Language:
- English
- Description:
- Studies were conducted investigating the responses of female obliquebanded leafrollers, Choristoneura rosaceana (Harris) and redbanded leafrollers, Argyrotaenia velutinana (Walker) (Lepidoptera: Tortricidae), to components of their sex pheromone. Electroantennogram (EAG) recordings revealed significant responses from antennae of female moths of both species to the major pheromone component, (Z)-11-tetradecenyl acetate, at dosages ranging from 2 µg - 2 mg. However, tested individually, the minor pheromone components of the obliquebanded leafroller, (E)-11-tetradecenyl acetate and (Z)-11-tetradecenol, elicited little or no antennal response from conspecific females. This result was consistent for redbanded leafroller females, which showed only weak responses to the minor component (E)-11-tetradecenyl acetate at a 2 mg dosage. For both species, species-specific blend ratios of the Z and E isomers of tetradecenyl acetate did not elicit a greater antennal response than the Z isomer alone. Virgin females of each species (2-4 d old) were placed into 1-liter plastic assay chambers with constant throughput of carbon-filtered air passed through 1-liter flasks containing rubber septa loaded with (Z)- and (E)-11-tetradecenyl acetates and (Z)-11-tetradecenol for trials with female obliquebanded leafrollers or with (Z)- and (E)-11-tetradecenyl acetates and dodecyl acetate for trials with female redbanded leafrollers. Exposure to pheromone-permeated air delayed the onset of calling by 1 h and terminated the calling period 1 h earlier for both species compared with solvent-control exposed females. Furthermore, the total proportion of calling females was reduced by half in chambers receiving constant throughput of pheromone-permeated air compared with solvent controls. Exposure to pheromone-permeated air also significantly reduced egg-laying in both species compared with clean-air controls. Furthermore, application of the major pheromone component, (Z)-11-tetradecenyl acetate, at dosages ranging from 2 µg - 2 mg to wax-paper ovipositional substrates, deterred oviposition by females of both species. Our data suggest that application of synthetic sex-attractant pheromones for mating disruption of leafroller species may have deleterious effects on female moth behavior, which may contribute to pest control. Field investigations will need to be conducted to test this hypothesis.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3179. Comparative dispersal and larvicidal activity of exotic and Azorean isolates of entomopathogenic nematodes against Popillia japonica (Coleoptera: Scarabaeidae)
- Creator:
- Lacey, Lawrence A., Rosa, Silvino J., Simoes, Nelson O., Amaral, Joao J., and Kaya, Harry K.
- Type:
- article, model:article, and TEXT
- Subject:
- Steinernema carpocapsae, Steinernema glaseri, Heterorhabditis bacteriophora, Heterorhabditidae, Steinernematidae, Japanese beetle, Popillia japonica, and dispersal
- Language:
- English
- Description:
- The Japanese beetle, Popillia japonica Newman, is an introduced pest on Terceira, one of nine islands in the Azorean Archipelago. Research conducted on Terceira indicates that entomopathogenic nematodes in the families Steinernematidae and Heterorhabditidae provide good to excellent control of Japanese beetle larvae, but the species that have been evaluated are not native to the Azores. An efficacious species that is native to the archipelago might provide increased capabilities for persisting and recycling in Azorean soil and weather conditions. Surveys on the islands of Terceira and Santa Maria resulted in the isolation of two Heterorhabditis strains (São Mateus and Praia Formosa) with good larvicidal activity for P. japonica. Initial bioassays conducted with Steinernema glaseri (Steiner) originally from North Carolina against P. japonica third instar larvae and pupae produced LC50 values of 3.2 × 105 infective juveniles (IJs)/m2 and 0.9 × 105 IJs/m2, respectively. Comparative bioassays of the native isolates and S. glaseri against P. japonica revealed similar larvicidal activity. The LC50s of the São Mateus and Praia Formosa isolates against third instar larvae were 3.64 × 105 and 4.44 x 105 IJs/m2, respectively. The LC50 of S. glaseri ranged from 3.2 to 5.5 × 105 IJs/m2. The higher larvicidal activity of the Azorean Heterorhabditis isolates for P. japonica indicates that native nematodes are as effective as S. glaseri. Heterorhabditid species also have demonstrated ability for persistence and apparent recycling under conditions where sustainable control of this introduced pest is needed. Studies comparing the dispersal behavior of the Heterorhabditis bacteriophora Poinar São Mateus isolate with that of S. glaseri and native and exotic strains of Steinernema carpocapsae (Weiser) revealed that the H. bacteriophora isolate demonstrated a greater propensity to disperse than other strains in the presence or absence of P. japonica larvae. In the presence of a host, a greater proportion of H. bacteriophora and S. glaseri dispersed than either of the two S. carpocapsae strains.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3180. Comparative dynamics of uterine echo dimentions in health and secondary amenorrhea
- Creator:
- Kasym-Hojaev, Ibragim, Kamalova, Gulnora, Negmatshaeva, Habiba, and Khankeldieva, Hurmatoy
- Format:
- electronic, electronic resource, and remote
- Type:
- model:article, article, Text, and TEXT
- Language:
- English
- Description:
- Protection of reproductive health of adolescents and youth, i.e., individuals aged 15 to 24 years, is a primary goal of a family planning service as according to WHO estimations (1995), the youth aged 15 to 24 years makes over 14% of the overall population in developed countries. Disorders of a menstrual cycle take a leading place among gynaecologic pathologies of adolescent girls. At the same time, according to WHO data, about 30% of schoolchildren suffer from iron deficiency anemia, which takes one of the first places in the structure of somatic pathologies. On the basis of maternity welfare centre No. 2, 2,456 girls aged 15 to 18 years were examined, and the frequency of occurrence and structure of disorders of a menstrual cycle was studied. In addition to standard methods of examination, all patients undertook USI of small pelvis organs; indicators of a hormonal status, complete blood test, transport fund, and iron stocks were investigated. The study included 285 girls, with various disorders of a menstrual cycle, who had no history of iron deficiency states and exacerbation of chronic diseases. The control group included 69 adolescent girls with a regular menstrual cycle. The most common type of disorder of a menstrual cycle in subjects examined was dysmenorrhea I. Iron deficiency anaemia was found in 5.3% of the subjects examined. The frequency of occurrence of moderate anaemia and latent deficiency of iron of 46.7% and 11.9%, respectively, attracts our attention. Well-timed diagnostics of the states mentioned in adolescent girls can prevent subsequent development of reproductive and somatic pathologies., Ibragim Kasym-Hojaev, Gulnora Kamalova, Habiba Negmatshaeva, Hurmatoy Khankeldieva, and Literatura
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public