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508342. Two species of philometrid nematodes (Philometridae) from marine fishes off Japan, including Philometroides branchiostegi sp. n. from Branchiostegus japonicus (Malacanthidae)
- Creator:
- Moravec, František, Nagasawa, Kazuya, and Nohara, Kenji
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parasitic nematode, Philometra, Philometroides, marine fish, Branchiostegus, Acanthogobius, Pterogobius, Sea of Japan, and Japan
- Language:
- English
- Description:
- Gravid females of two species of philometrid nematodes (Philometridae) were collected from marine perciform fishes in Japanese waters, mainly from the southern Sea of Japan. Based on light microscopy and scanning electron microscopy examinations, the previously described but poorly known species Philometra cryptocentri Yamaguti, 1961 is redescribed from specimens recovered from the abdominal cavity of Acanthogobius flavimanus (Temminck et Schlegel), Pterogobius elapoides (Günther) and P. zonoleucus Jordan et Snyder (all Gobiidae) (all new host records); the number (14) and arrangement of cephalic papillae in this species are described for the first time. The new species, Philometroides branchiostegi sp. n. from head tissues of Branchiostegus japonicus (Houttuyn) (Malacanthidae), based on a single specimen, is mainly characterized by the embossment of the entire body except for the cephalic end, presence of four submedian pairs of large cephalic papillae of external circle and two small lateral single papillae of internal circle, pair of large papilla-like caudal projections, the oesophagus with a distinct anterior inflation, by a markedly small body (length about 18 mm) and the larvae 306-465 µm long.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
508343. Two species of Rhabdochona (Nematoda: Rhabdochonidae) from the cyprinid fish Luciobarbus kersin (Heckel) in northern Iraq, including R. (Globochona) kurdistanensis sp. n.
- Creator:
- Moravec, František, Bilal, Samir J., and Abdullah, Shamall M. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Parasitic nematode, Rhabdochona, freshwater fish, Luciobarbus, and Iraq
- Language:
- English
- Description:
- A new nematode species, Rhabdochona (Globochona) kurdistanensis sp. n. (Rhabdochonidae), is decribed based on specimens collected from the intestine of the barbel Luciobarbus kersin (Heckel) (Cyprinidae) in the Greater Zab (type locality) and the Lesser Zab Rivers, Tigris River basin, Kurdistan Region, northern Iraq. It is mainly characterized by a prostom with 8 anterior teeth, the presence of basal prostomal teeth, bifurcated deirids, length ratio of the muscular and glandular portions of oesophagus (1:14.4-17.8), conspicuously short left spicule (180-204 µm), arrangement of genital papillae, nonfilamented eggs, and by having cuticular ornamentations on the tail tip (2 lateral denticular outgrowths in female and numerous fine spines in male). Description of a gravid female of Rhabdochona (Rhabdochona) sp. with 14 anterior prostomal teeth and filamented eggs, recorded from L. kersin of the Greater Zab River, is also provided. R. kurdistanensis sp. n. is the fifth valid species of Rhabdochona Railliet, 1916 and the only representative of the subgenus Globochona Moravec, 1972 recorded from Iraq.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
508344. Two types of high inductive electromagnetic stimulation and their different effects on endothelial cells
- Creator:
- Průcha, J. , Skopalik, J. , Socha, V., Hanáková, L., Knopfová, L. , and Hána, K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- low frequency-electromagnetic fields, induced electric currents, neoangiogenesis, and endothelial cells
- Language:
- English
- Description:
- Effects of low-frequency electromagnetic fields (LF EMF) on the activation of different tissue recovery processes have not yet been fully understood. The detailed quantification of LF EMF effects on the angiogenesis were analysed in our experiments by using cultured human and mouse endothelial cells. Two types of fields were used in the tests as follows: the LF EMF with rectangular pulses, 340-microsecond mode at a frequency of 72 Hz and peak intensity 4 mT, and the LF EMF with sinusoidal alternating waveform 5 000 Hz, amplitude-modulated by means of a special interference spectrum mode set to a frequency linear sweep from 1 to 100 Hz for 6 s and from 100 Hz to 1 Hz return also for 6 s, swing period of 12 second. Basic parameters of cultured cells measured after the LF EMF stimulus were viability and proliferation acceleration. Both types of endothelial cells (mouse and human ones) displayed significant changes in the proliferation after the application of the LF EMF under conditions of a rectangular pulse mode. Based on the results, another test of the stimulation on a more complex endothelial-fibroblast coculture model will be the future step of the investigation.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
508345. Two types of refuge have opposite effects on the size of larval aggregations in a tropical defoliator
- Creator:
- Horgan, Finbarr G.
- Type:
- article, model:article, and TEXT
- Subject:
- Defence, density responses, El Salvador, Ficus, gregariousness, parasitism, refuges, Tachinidae, tiger moth, and tropical defoliator
- Language:
- English
- Description:
- Many gregarious insects aggregate in naturally occurring refuges on their host plants. However, when refuges are filled, they may be forced to aggregate on exposed areas of the plant. This study examines the effects of refuge saturation on group size and defence against parasitism in larvae of Ammalo helops Cramer (Lepidoptera: Arctiidae) that form day-resting groups on the trunks of weeping laurel, Ficus benjamina L., in El Salvador. Population densities, group sizes and parasitism were recorded on eight trees for each of four generations in 1995 and 1996. When population densities were low, all larvae were located in small groups in naturally occurring structural refuges (rotted out holes, spaces between crossing branches and under aerial roots) on the host plant. In contrast, when population densities were high and structural refuges were full, many larvae formed significantly larger groups (density refuges) on the open trunk. Between 20 and 24% of late-instar larvae were parasitized and this was inversely dependent on the size of within tree populations, in spite of populations being fragmented among structural refuges. Similarly, in a study carried out at a different location on young trees without structural refuges, parasitism of larvae was inversely related to group size. Although parasitism rates decreased with increasing group size, most larvae preferentially selected the small naturally occurring refuges, where groups were restricted to low densities. If this behaviour is an adaptive trait, I speculate that parasitism (or some other unmeasured mortality factor) is lower in naturally occurring refuges than in large open groups.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
508346. Two valued measure and some new double sequence spaces in $2$-normed spaces
- Creator:
- Das, Pratulananda, Savas, Ekrem, and Bhunia, Santanu
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- convergence, $\mu $-statistical convergence, convergence in $\mu $-density, condition (APO$_{2}$), 2-norm, 2-normed space, paranorm, paranormed space, Orlicz function, and sequence space
- Language:
- English
- Description:
- The purpose of this paper is to introduce some new generalized double difference sequence spaces using summability with respect to a two valued measure and an Orlicz function in $2$-normed spaces which have unique non-linear structure and to examine some of their properties. This approach has not been used in any context before.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
508347. Two valued measure and summability of double sequences
- Creator:
- Das, Pratulananda and Bhunia, Santanu
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- double sequences, $\mu $-statistical convergence, divergence and Cauchy criteria, convergence, divergence and Cauchy criteria in $\mu $-density, and condition (APO$_2)$
- Language:
- English
- Description:
- In this paper, following the methods of Connor \cite {connor}, we extend the idea of statistical convergence of a double sequence (studied by Muresaleen and Edely \cite {moe}) to $\mu $-statistical convergence and convergence in $\mu $-density using a two valued measure $\mu $. We also apply the same methods to extend the ideas of divergence and Cauchy criteria for double sequences. We then introduce a property of the measure $\mu $ called the (APO$_2$) condition, inspired by the (APO) condition of Connor \cite {jc}. We mainly investigate the interrelationships between the two types of convergence, divergence and Cauchy criteria and ultimately show that they become equivalent if and only if the measure $\mu $ has the condition (APO$_2$).
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
508348. Two wavelenght picosecond ranging of ground target
- Creator:
- Hamal, K., Prochazka, I., and Gaignebet, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- scientific research, two wavelenght experiment, and Nd YAG laser
- Language:
- Czech
- Description:
- One of the limiting factors in decreasing the systematic error of laser ranging is the influence of the atmospheric refraction. Two colour ranging may contribute useful information for more precise refraction factor modelling and calculation. We will describe two wavelength experiment using streak camera as a high resolution detector for ground target distance measurement.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
508349. Two ways of experimental infection of Ixodes ricinus ticks (Acari: Ixodidae) with spirochetes of Borrelia burgdorferi sensu lato complex
- Creator:
- Fišerová, Lenka, Černá, Kateřina, Horká, Helena, and Kopecký, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Lyme disease spirochete, Borrelia burgdorferi, Borrelia garinii, Borrelia afzelii, tick, and Ixodes ricinus
- Language:
- English
- Description:
- A previously reported procedure for the introduction of Borrelia spirochetes into tick larvae by immersion in a suspension of spirochetes was tested on Ixodes ricinus (L.) ticks and three of the most medically important European Borrelia genomic species, B. burgdorferi sensu stricto, B. garinii and B. afzelii. The procedure was compared with ''classical'' infection of nymphs by feeding on infected mice. Both methods yielded comparable results (infection rate 44-65%) with the exception of B. afzelii, which produced better results using the immersion method (44%) compared with feeding on infected mice (16%). Nymphs infected by the immersion method at the larval stage were able to transmit the infection to naïve mice as shown by serology and PCR detection of spirochetal DNA in organs. The immersion method is faster than feeding on infected mice and provides more reproducible conditions for infection. It can be exploited for studies on both pathogen transmission and Borrelia-vector interactions.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
508350. Two ways of finding a host: A specialist and a generalist parasitoid species (Hymenoptera: Chalcidoidea: Pteromalidae)
- Creator:
- Peters, Ralph S.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Hymenoptera, Chalcidoidea, Pteromalidae, Nasonia vitripennis, Dibrachys microgastri, parasitic wasps, specialist, generalist, locomotor activity, laboratory experiments, parasitoid life history traits, host finding, olfactory cues, 2, and 59
- Language:
- English
- Description:
- Two closely related parasitoid wasp species with different host specificities were used for experimental studies on the biology of host finding, a crucial element of parasitoid life history: The habitat and host specialist Nasonia vitripennis and the habitat and host generalist Dibrachys microgastri (Chalcidoidea: Pteromalidae). The host finding parameters tested included reaction to olfactory cues, aspects of locomotor activity, ability to locate hidden hosts and day-night-activity. The results revealed distinct interspecific differences that match the respective host and habitat ranges of the two species. In N. vitripennis host finding is dominated by olfactory reaction to hosts and host habitat, i.e., fly puparia and birds' nests. In D. microgastri olfactory cues have only a minor role. Its host finding is characterized by rapid searching at random. Both species are able to locate hidden hosts. Although still incomplete, these insights into host finding by two parasitoid species with different life history strategies indicate they can be characterized by specific combinations of behavioural host finding features. and Ralph S. Peters.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public