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3182. Biometry of the large dragonfly Anax imperator (Odonata: Aeshnidae): a study of traits from larval development to adults
- Creator:
- Minot, Marceau, Le Gall, Mickaël , and Husté, Aurélie
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Odonata, Aeshnidae, Anax imperator, body length, body mass, larval rearing, sexual size dimorphism, and traits
- Language:
- English
- Description:
- Insect larval development affects adult traits but the biometric relationships are usually poorly understood, including large odonates. In this study, measurements of morphological traits of larvae, exuviae and adults of Anax imperator were recorded. They were used to investigate the effects of early development on adult morphology. Results showed an increase in larval length during the final instar and the length of its exuviae significantly exceeded that of the larva. Length and body mass of teneral adults were strongly related to the length of their exuviae. Adult males were significantly longer than adult females, while both had the same body mass at emergence. Length of teneral adults was negatively related to the date of emergence in both sexes. During maturation, body mass of males only increased slightly whereas that of females increased greatly. Mature specimens were also significantly longer than teneral individuals. Body mass of mature males and length of mature females were both associated with the date of capture. Wing length did not differ between sexes or from data available from Great Britain. This study underscores the importance of taking into account larval growth in order to better understand the adult traits of odonates.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3183. Bionomics and ecology of Bemisia tabaci (Sternorrhyncha: Aleyrodidae) in Italy
- Creator:
- Bosco, Domenico and Caciagli, Piero
- Type:
- article, model:article, and TEXT
- Subject:
- Aleyrodidae, Bemisia tabaci, developmental time, cold resistance, overwintering, Italy, and distribution
- Language:
- English
- Description:
- The development of a B-biotype Bemisia tabaci Italian colony was studied on bean at 9 constant temperatures (15, 16, 17, 20, 23, 26, 29, 32, 35°C). The developmental time from egg-to-adult varied from 70 days at 16°C to 22 at 26°C and higher temperatures. A thermal requirement for egg-to-adult development of 307 day-degrees was calculated, based on a lower developmental threshold of 11.53°C. The survival of egg, nymph and adult whiteflies was investigated at 0, 2, 4, and 6°C on broad bean for periods of 1-8 days. The adult was the most cold-sensitive stage, while the egg and nymph showed a similar level of cold resistance. The effect of sub-lethal cold stress of 4-8 days at 4°C on eggs and nymphs was studied. After exposure to low temperatures, whiteflies needed longer developmental times, from 5 to 8 days more. The presence of B. tabaci under outdoor conditions in Italy was investigated with field surveys and correlated with climatic data; the whitefly species was found in open field conditions only south of the 41° parallel, in areas characterised by less than 5 frost days per winter and by annual mean temperatures >16°C.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3184. Biophysical investigation on left ventricular myocytes in rats with experimentally induced diabetes
- Creator:
- Waczulíková, I., Cagalinec, M., Oľga Uličná, Peter Slezák, and Atila Ziegelhöffer
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, membrány, mitochondrie, fluorescenční spektroskopie, fluorescenční mikroskopie, membranes, mitochondrias, fluorescent spectroscopy, fluorescence microscopy, left ventricular myocytes, biophysical properties, 14, and 612
- Language:
- English
- Description:
- Diabetes is a recognized risk factor of heart disease. The abnormalities related to a decreased heart performance probably arise at cellular and molecular levels already in the asymptomatic phase of diabetes. However, the early alterations initiating a sequence of events that culminates in the clinical signs have not been fully elucidated yet. This review deals with some biophysical methods applied to investigation of left ventricular myocytes in rats with streptozotocin diabetes, as well as our most important findings concerning diabetes-induced cell changes which cannot be captured by other techniques. The observed decrease in sarcolemmal membrane fluidity is causatively associated with increased glycation and glycoxidation. On the other hand, an increase in the mitochondrial membrane fluidity may be attributed to augmented energy transduction through the membranes. We reported for the first time concurrent measurements of membrane potential and dynamics, and respiratory chain activities in rat heart mitochondria, as well as calcium transients in the myocytes from diabetic hearts together with the assessed quantitative relationships among these variables. We were able to detect some significant alterations that may underlie myocyte dysfunction and subsequent remodeling of the heart. We suppose that not all these changes reflect mechanisms leading to pathology; some may represent adaptive and compensatory responses to diabetes., I. Waczulíková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3185. Biosystematic study of the Cyanus triumfetti group in Central Europe
- Creator:
- Olšavská, Katarína, Perný, Marián, Kučera, Jaromír, and Hodálová, Iva
- Type:
- article and TEXT
- Subject:
- Asteraceae, Cyanus sect. Perennes, flow cytometry, genetic variation, morphology, Pannonia, taxonomy, and Western Carpathians
- Language:
- English
- Description:
- Multivariate morphometrics and an assessment of genetic diversity obtained using amplified fragment length polymorphism (AFLP) were used to determine the variability of the polymorphic group Cyanus triumfetti in Central Europe. The ploidy level of the populations studied was also determined; all individuals from the C. triumfetti group were diploid (2n ~ 2x ~ 22) and all those of the related C. montanus group were tetraploid (2n ~ 4x ~ 44). A multivariate morphometric study of 71 populations revealed that three species from the C. triumfetti group occur in Central Europe, namely ‘Cyanus axillaris’, C. strictus and C. dominii. Three subspecies are recognized within the latter species, namely C. dominii subsp. dominii, C. dominii subsp. slovenicus and C. dominii subsp. sokolensis. Morphological characters of leaves are the best features for delimiting these taxa; a shift in characters caused by cultivation did not affect the value of key characters and differences among the taxa remained. AFLP analysis of 38 populations from the C. triumfetti group and two from the C. montanus group revealed a contrasting pattern of genetic variation that was related to the geographic distribution of the populations rather than the morphological variation in the C. triumfetti group. The AFLP data revealed the following three genetically differentiated and allopatric groups: (i) C. triumfetti s.s. and C. montanus from the Western Alps, (ii) ‘C. axillaris’ from Austria and the Czech Republic (except the Carpathians) and (iii) ‘C. axillaris’, C. strictus and C. dominii from the Western Carpathians and Pannonia. The striking genetic gap between the Austrian-Czech and the W Carpathian-Pannonia groups and the high genetic diversity and weak genetic differentiation within the latter group are discussed in the light of potential glacial refuges, postglacial migration routes and/or the probability of hybridization events occurring during the evolutionary history of this group. An identification key for the taxa of the C. triumfetti group in Central Europe is presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
3186. Biphasic ventilatory response to hypoxia in unanesthetized rats
- Creator:
- Hana Maxová and Martin Vízek
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, větrání, ventilation, biphasic response to hypoxia, diaphragmatic activity, pattern of breathing, 14, and 612
- Language:
- English
- Description:
- To determine the role of postinspiratory inspiratory activity of the diaphragm in the biphasic ventilatory response to hypoxia in unanesthetized rats, we examined diaphragmatic activity at its peak (DI), at the end of expiration (DE), and ventilation in adult unanesthetized rats during poikilocapnic hypoxia (10 % O2) sustained for 20 min. Hypoxia induced an initial increase in ventilation followed by a consistent decline. Tidal volume (VT), frequency of breathing (fR), DI and DE at first increased, then VT and DE decreased, while fR and DI remained enhanced. Phasic activation of the diaphragm (DI - DE) increased significantly at 10, 15 and 20 min of hypoxia. These results indicate that 1) the ventilatory response of unanesthetized rats to sustained hypoxia has a typical biphasic character and 2) the increased end-expiratory activity of the diaphragm limits its phasic inspiratory activation, but this increase cannot explain the secondary decline in tidal volume and ventilation., H. Maxová, M. Vízek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3187. Bipteria formosa (Kovaleva et Gaevskaya, 1979) comb. n. (Myxozoa: Myxosporea) in whiting Merlangius merlangus (Teleostei: Gadidae) from Denmark
- Creator:
- Karlsbakk, Egil and Køie, Marianne
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Myxozoa, Bipteria formosa, Myxoproteus formosus, Zschokkella hildae, Gadimyxa, Merlangius merlangus, 18S rDNA sequences, and Denmark
- Language:
- English
- Description:
- A total of 22 specimens of whiting Merlangius merlangus (L.) (Teleostei, Gadidae) from the northern Øresund, Denmark were examined for Myxosporea. Zschokkella hildae Auerbach, 1910 (Myxidiidae), Gadimyxa sp. (Parvicapsulidae) and a species of Bipteria occurred in the renal tubules of 9%, 18% and 68% whiting, respectively. Immature spores of the Bipteria species are very similar to spores of Myxoproteus formosus Kovaleva et Gaevskaya, 1979 originally described from the urinary system of whiting from the Celtic Sea. We therefore consider Bipteria sp. from whiting in Denmark conspecific with M. formosus and propose Bipteria formosa (Kovaleva et Gaevskaya, 1979) comb. n. The spore of Bipteria formosa is described in detail and compared with other Bipteria spp. The phylogenetic position of B. formosa, based on partial 18S rDNA sequences, is closest to Leptotheca fugu Tun, Yokoyama, Ogawa et Wakabayashi, 2000 and the Sphaerosporidae.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3188. bird assemblage of coastal borrowdykes in relation to habitat features
- Creator:
- Mason, Christopher F. and MacDonald, Sheila M.
- Type:
- article and TEXT
- Subject:
- borrowdyke, wetland, wetland birds, reedbed, and conservation
- Language:
- English
- Description:
- The birds along twenty 500 m lengths of coastal borrowdyke (water-filled ditches left when clay is extracted to make a sea wall) in eastern England were counted in spring 2004 and occurrence related to features of habitat. A total of 45 species was recorded with species richness ranging from 5–21. The most widespread species were little grebe Tachybaptus ruficollis, mute swan Cygnus olor, mallard Anas platyrhynchos, moorhen Gallinula chloropus, coot Fulica atra, sedge warbler Acrocephalus schoenobaenus, reed warbler Acrocephalus scirpaceus and reed bunting Emberiza schoeniclus, all typical wetland birds. Of 20 habitat variables measured, six (open water, narrow and broad marginal Scirpus, width, and low and tall thick scrub) were significant in describing species abundance data in a Canoco analysis. The linear coastal habitat of borrowdykes is regionally important for the conservation of some wetland species and current rotational management for land drainage purposes maintains the variety of habitats to retain a diversity of bird species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
3189. Bird schistosomes of wildfowl in the Czech Republic and Poland
- Creator:
- Rudolfová, Jitka, Littlewood, D. T. J., Sitko, Jiljí, and Horák, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- schistosomes, wildfowl, Trichobilharzia, and Bilharziella
- Language:
- English
- Description:
- In 2005, we dissected 102 wildfowl from the Czech Republic and 73 wildfowl from Poland including representatives of Anseriformes, Gruiformes and Gaviiformes. Schistosome infection was found in a total of 21 (29%) and 23 (23%) birds from Poland and the Czech Republic, respectively. All infected birds belonged to the order Anseriformes. The prevalences of nasal and visceral species were, respectively, 22% and 16% in Poland and 6% and 19% in the Czech Republic. Four species of schistosomes were found: Bilharziella polonica Kowalewski, 1895, Trichobilharzia regenti Horák, Kolářová et Dvořák, 1998, T. szidati Neuhaus, 1952, and an undetermined schistosome from the intestinal wall of Anas penelope L. The finding of T. szidati represents the first record of the parasite from natural final host since the species description.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3190. Bitis, Alexander. Russia and the Eastern Question Army, Government and Society
- Creator:
- Šedivý, Miroslav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public