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52. Life cycles in polar arthropods - flexible or programmed?
- Creator:
- Danks, Hugh V.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Arctic, Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), climate, temperature, seasonal, life-cycle, arthropods, insects, polar, Antarctic, zoologie, fyziologie živočichů, ekofyziologie, členovci, hmyz, životní cykly, sezónní vlivy, klimatické vlivy, teplota, arktická oblast, antarktická oblast, fenologická studie, přehledy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- Climate features that influence life cycles, notably severity, seasonality, unpredictability and variability, are summarized for different polar zones. The zones differ widely in these factors and how they are combined. For example, seasonality is markedly reduced by oceanic influences in the Subantarctic. Information about the life cycles of Arctic and Antarctic arthropods is reviewed to assess the relative contributions of flexibility and programming to life cycles in polar regions. A wide range of life cycles occurs in polar arthropods and, when whole life cycles are considered, fixed or programmed elements are well represented, in contrast to some recent opinions that emphasize the prevalence of flexible or opportunistic responses. Programmed responses ale especially common for controlling the appearance of stages that are sensitive to adverse conditions, such as the reproductive adult. The relative contribution of flexibility and programming to different life cycles is correlated with taxonomic affinity (which establishes the general lifecycle framework for a species), and with climatic zone, the habitats of immature and adult stages, and food., Hugh V. Danks, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
53. Marše pobřežní - stálice štěrkových lavic
- Creator:
- Kuřavová, Kateřina
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, hmyz, životní prostředí, Morávka (Česko : řeka), Morávka River (Czechia), 2, and 59
- Language:
- Czech
- Description:
- Vodní toky v ČR jsou v posledních sto letech vystaveny intenzivnímu antropogennímu tlaku. Tyto činnosti se projevují také na populaci druhu marše pobřežní (Tetrix tuerki), který se vyskytuje se pouze na štěrkových lavicích podhorských potoků a řek. Národní přírodní památka Skalická Morávka je ideálním místem pro tento druh. Dynamika štěrkových lavic je velmi důležitá pro existenci tohoto druhu., Water flows have been under intensive anthropogenic pressure over the last 100 years. These activities also influenced populations of Tetrix tuerki, which only occurs on gravel benches of streams and rivers (dynamics of the benches are crucial for its existence). The National Natural Monument Skalická Morávka provides an ideal habitat., and Kateřina Kuřavová.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
54. Metabolic neurohormones: release, signal transduction and physiological responses of adipokinetic hormones in insects
- Creator:
- Van Der Horst, Dick J., Van Marrewijk, Wil J. A., Vullings, Henk G. B., and Diederen, Jacques H. B.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, Locusta migratoria, metabolismus, metabolické neurohormony, adipokinetické hormony, biosyntéza, vylučování, přenos signálu, mechanismus přenosu, 595.2/.7, and 591.1
- Language:
- English
- Description:
- In view of the extremely high metabolic rates involved, insect flight offers a fascinating model system for studying metabolism during exercise, including its regulation by metabolic neurohormones. In our laboratory the African migratory locust, Locusta migratoria, well-known for its long-distance flights, is used as an internationally recognized model insect. The insect is mass-reared under controlled conditions; its size permits convenient handling in vivo and in vitro, while flight activity can be easily evoked. In addition, research on this pest insect may be of economical importance. A survey of the energy metabolism during locust flight is presented in Fig. 1. Flight activity stimulates the neurosecretory adipokinetic cells in the glandular lobes of the corpus cardiacum, a neuroendocrine gland connected with the insect brain, to release peptide neurohormones, the adipokinetic hormones (AKHs). The target for these hormones is the fat body. Via signal transduction processes, the action of the hormones ultimately results in the mobilization of both carbohydrate and lipid reserves as fuels for flight. Carbohydrate (trehalose) is mobilized from glycogen reserves, implying hormonal activation of the key enzyme, fat body glycogen phosphorylase, by phosphorylation. Similarly, on the lipid side, sn-1,2-diacylglycerol (DAG) is mobilized from stored triacylglycerol (TAG), by hormonal activation of the fat body TAG lipase. The carbohydrate and lipid substrates are transported in the hemolymph to the contracting flight muscles. Carbohydrate provides most of the energy for the initial period of flight, whereas at a later stage, lipid substrate in the blood is increased and gradually takes over. The transport of DAG requires specific lipoprotein carriers (lipophorins) which differ in several respects from the lipoproteins in mammals, and act as a lipid shuttle. This review is focused on three interrelated topics, covering recent data on the biosynthesis and release of the AKHs, their signal transduction mechanisms in the fat body cells, and the changes in the lipophorin system induced by the AKHs during flight., Dick J. Van Der Horst, Wil J.A. Van Marrewijk, Henk G.B. Vullings, Jacques H.B. Diederen, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
55. Monophyly of the subgenus Leptempis, and description of seven new species of the Empis (Leptempis) rustica-group (Diptera: Empididae)
- Creator:
- Daugeron, , Christophe
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, entomologie, hmyz, dvoukřídlí, Empididae, Empis, Leptempis, Leptempis rustica, nové druhy, taxonomie, fylogeneze, monofylie, and 595.2/.7
- Language:
- English
- Description:
- The monophyly of the subgenus Leptempis Collin of the genus Empis L. is established on the basis of a male hypopygial character, and the possibility of a close relationship between the subgenera Leptempis Collin, Planempis Frey and Kritempis Collin is discussed. Seven new species belonging to Empis (Leptempis) rustica-group are described from France, Germany, Greece and Spain: E. (L.) abdominalis sp. n., E. (L.) lamellata sp. n., E. (L.) multispina sp. n., E. (L.) pandellei sp. n., E. (L.) lamellimmanis sp. n., E. (L.) sinuosa sp. n. and E. (L.) trunca sp. n. A key to the E. (L.) rustica-group is presented., Christophe Daugeron, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
56. Mor, Yersinia pestis, blecha a člověk
- Creator:
- Konopásek, Ivo
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, molekulární biologie, virologie, mor, hmyz, pathology, zoology, plague, insects, 2, and 577
- Language:
- Czech
- Description:
- Mor je zoonóza, jejíž epidemie sužují lidstvo od starověku. Od objevu bakteriálního původce moru A. Yersinem a S. Kitasatem uplynulo 120 let, během kterých byla tato choroba velmi dobře popsána jak z epidemiologického, tak z molekulárně mikrobiologického a evolučního hlediska. Studiem DNA izolované z ostatků obětí moru byl původce moru přímo prokázán u epidemií starých až 650 let. Vysoká mortalita při moru je dána neefektivním přenosem mezi hostiteli pomocí blechy jako vektoru., Plague is a zoonotic disease, the epidemics of which have troubled mankind since ancient times. During the last 120 years that have passed since the discovery of the plague bacillus Y. pestis by A. Yersin and S. Kitasato this infectious disease was described in detail, including its epidemiology, molecular microbiology and evolution. Ancient DNA isolated from the remains of plague victims have enabled us to establish Y. pestis as the causative agent in epidemics more than 650 years old. The high mortality of the plague is caused by an ineffective transfer by its flea vector., and Ivo Konopásek.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
57. Musca, cratura minima :
- Creator:
- Studničková, Milada,
- Type:
- text and studie
- Subject:
- Výtvarné umění, umění výtvarné, obrazy středověké, hmyz, ikonografie, světové dějiny středověku (do r. 1492), and jazyk, písmo
- Language:
- Czech
- Rights:
- unknown
58. Myotropic neuropeptides from the retrocerebral complex of the stick insect, Carausius morosus (Phasmatodea: Lonchodidae)
- Creator:
- Predel, Reinhard, Kellner, Roland, and Gäde, Gerd
- Format:
- print, text, and regular print
- Type:
- article, bibliography, model:article, and TEXT
- Subject:
- zoologie, hmyz, Phasmatodea, Lonchodidae, Carausius morosus, neuropeptidy, myotropin, myotropické neuropeptidy, izolace, bioaktivita, 595.2/.7, and 591.1
- Language:
- English
- Description:
- Myotropic neuropeptides were isolated from the retrocerebral complex of the stick insect, Carausius morosus, by using three HPLC steps. Bioactivity during purification was measured by heterologous bioassays monitoring the contractions of the hyperneural muscle and hindgut of the American cockroach. Additionally, fractions not active in these bioassays were tested in a homologous bioassay evoking contractions of the hindgut of C. morosus. Peptide sequence analysis and mass spectrometry yielded the following structures: Pro-Phe-Cys-Asn-Ala-Phe-Thr-Gly-Cys-NH2 (CCAP), pGlu-Thr-Phe-Gln-Tyr-Ser-His-Gly-Trp-Thr-Asn-NH2 (His7-corazonin) and Asp-Glu-Gly-Gly-Thr-Gln-Tyr-Thr-Pro-Arg-Leu-NH2 (Cam-PK-1). These neuropeptides are the first myotropins isolated from C. morosus. The most bioactive compound in the homologous bioassay, the C. morosus-hindgut assay, was CCAP., Reinhard Predel, Roland Kellner, Gerd Gäde, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
59. Naši rýhonosci. 1. Nosatí elegáni
- Creator:
- Robert Stejskal and Trnka, Filip
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, hmyz, brouci, nosatcovití, biologické druhy, morfologie živočichů, škůdci rostlin, insects, beetles, Curculionid beetles, biological species, animal morphology, pests of plants, Česko, Czechia, 595.76, 2, and 59
- Language:
- Czech
- Description:
- This paper introduces a very interesting group of curculionid beetles – weevils of the tribe Cleonini. This tribe includes quite a remarkable large species associated with non-forest habitats, most of which are currently considered endangered. In spite of being very popular among coleopterists, this group of beetles has not been studied in detail within the Czech Republic. and Robert Stejskal, Filip Trnka.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
60. Naši rýhonosci. 2. Napudrovaní krasavci
- Creator:
- Robert Stejskal and Trnka, Filip
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, hmyz, brouci, nosatcovití, Česko, 2, and 59
- Language:
- Czech
- Description:
- This paper introduces a very interesting group of curculionid beetles–weevils of the tribe Lixini. This tribe includes a quite re-markable large species, most of which are currently considered endangered. They are associated with non-forest habitats and re-quire various kinds of habitat disturbation which ensures their successful survival., Robert Stejskal, Filip Trnka., and 13 barev. fot.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public