Search results for "juvenile"
showing 10 items of 366 documents
Plekstes (Platichthys flesus L) agrīno attīstības stadiju bioloģiskais raksturojums Baltijas jūras centrālajā daļā
2014
ANOTĀCIJA Ustups, 2013. Plekstes (Platichthys flesus L.) agrīno attīstības stadiju bioloģiskais raksturojums Baltijas jūras centrālajā daļā. Plekstu ihtioplanktona daudzumu Baltijas jūras centrālajā daļā nosaka nārsta bara lielums un hidroloģiskie apstākļi. Plekstu mazuļu skaitu piekrastes zonā būtiski ietekmē ūdens temperatūra, mēnesis un vēja virziens. Strauja šāgadeņu augšana novērojama līdz septembrim, bet viengadniekiem no pavasara līdz novembrim. Irbes šauruma piekraste ir labvēlīga dzīvotne plekstu mazuļiem, ko nosaka smilšainās seklūdens zonas, daudzveidīgie barošanās objekti un ģeogrāfiskais novietojums attiecībā pret nārsta vietu. Plekstes mazuļu plašais barības spektrs samazina b…
Juvenile autophagic vacuolar myopathy - a new entity or variant?
2013
A heterocyclic oxime from a fungus with anti-juvenile hormone activity
1998
Two fractions obtained after chromatography of dichloromethane extract of Penicillium brevicompactum culture medium showed anti-juvenile hormone activity. One was active when assayed in vivo against Oncopeltus fasciatus third-instar nymphs, whereas the other showed a strong in vitro inhibition of JH III biosynthesis on Locusta migratoria corpora allata. A subfraction of the latter, constituting 97% of this fraction, is a main component that possessed the juvenile hormone biosynthesis inhibitory activity. Chemical characterization of this compound shows a sesquiterpene-like structure, molecular mass of 278.16185 daltons, corresponding to an empirical formula of C15H22N2O3 named brevioxime. E…
Reproductive effects in German cockroaches by ecdysteroid agonist RH-0345, juvenile hormone analogue methoprene and carbamate benfuracarb
2004
1379-1176 (Print) Journal Article Research Support, Non-U.S. Gov't; Blatta germanica is the more prevalent cockroach species in Algeria. In the present study, we tested the effect on reproduction in B. germanica of two insect growth regulators, RH-0345, a benzoylhydrazine analogue that mimics the action of 20-hydroxyecdysone, and methoprene, one of the most commercially important juvenile hormone analogues, and a novel carbamate insecticide, benfuracarb. The compounds were applied topically (10 and 20 microg/insect for RH-0345, and 1 and 10 microg/insect for methoprene) or orally administrated (at 2% for benfuracarb) on newly emerged females and evaluated on reproductive events during the a…
Oxygen consumption of F0 and F1 larval and juvenile European seabass Dicentrarchus labrax in resonse to ocean acidification and warming
2022
Ongoing climate change is leading to warmer and more acidic oceans. The future distribution of fish within the oceans depends on their capacity to adapt to these new environments. Only few studies have examined the effects of ocean acidification (OA) and warming (OW) on the metabolism of long-lived fish over successive generations. We therefore aimed to investigate the effect of OA on larval and juvenile growth and metabolism on two successive generations of European sea bass (Dicentrarchus labrax L.) as well as the effect of OAW on larval and juvenile growth and metabolism of the second generation. European sea bass is a large economically important fish species with a long generation time…
Els estudiants valencians sota el franquisme
1999
Este artículo presenta un resumen del proceso de aparición, desarrollo y disolución del movimiento estudiantil antifranquista en la Universidad de Valencia. En priemr lugar, analiza sus antecedentes: la última resistencia democrática republicana en los años cuarenta y los cambios culturales de los años cincuenta. En segundo lugar, describe las dos estrategias -resistente y opositora- ensayadas por los nuevos disidentes desde 1957; y la superviviencia de la segunda, origen de un nuevo movimiento fue liderado primero por un grupo progresista y nacionalista: PSV, que fundó un sindicato estudiantil, ADEV, enfrentado al sindicato oficial (SEU). El PSV fue reemplazado a partir de 1966 por el PCE,…
Ovarian tissue in juvenile palaeacanthocephalans: Corynosoma semerme, C. strumosum and Echinorhynchus gadi
1986
SUMMARYThe structure of the ovarian tissue in juvenile Corynosoma semerme and C. strumosum from a fish paratenic host and in the cystacanth stage of Echinorhynchus gadi from an amphipod intermediate host was investigated by means of transmission electron microscopy. The species were obtained from hosts living in the Baltic Sea. The observations indicate that ovarian development was more advanced in cystacanths of E. gadi than in juveniles of C. semerme and C. strumosum. Free ovaries were present in E. gadi with an obvious supporting syncytium and surface microvilli. The biological significance of the different stages of ovarian development in these species is discussed briefly in relation t…
The regulation of expression of insect cuticle protein genes
2010
International audience; The exoskeleton of insects (cuticle) is an assembly of chitin and cuticle proteins. Its physical properties are determined largely by the proteins it contains, and vary widely with developmental stages and body regions. The genes encoding cuticle proteins are therefore good models to study the molecular mechanisms of signalling by ecdysteroids and juvenile hormones, which regulate molting and metamorphosis in insects. This review summarizes the studies of hormonal regulation of insect cuticle protein genes, and the recent progress in the analysis of the regulatory sequences and transcription factors important for their expression.
A novel putative insect chitinase with multiple catalytic domains: hormonal regulation during metamorphosis
2002
0264-6021 (Print) Journal Article Research Support, Non-U.S. Gov't; We have used differential display to identify genes that are regulated by juvenile hormone in the epidermis of the beetle Tenebrio molitor. One of the genes encodes T. molitor chitinase 5 (TmChit5), a chitinase possessing an unusual structure. Sequence analysis of TmChit5 identified five 'chitinase units' of approx. 480 amino acids with similarity to chitinase family 18. These units are separated by less conserved regions containing putative PEST (rich in proline, glutamic acid, serine and threonine) sequences, putative chitin-binding domains and mucin domains. Northern-blot analysis identified a single transcript of approx…
Pilot study on the combination of an organophosphate-based insecticide paint and pyrethroid-treated long lasting nets against pyrethroid resistant ma…
2015
International audience; A pilot study to test the efficacy of combining an organophosphate-based insecticide paint and pyrethroid-treated Long Lasting Insecticide Treated Nets (LLINs) against pyrethroid-resistant malaria vector mosquitoes was performed in a real village setting in Burkina Faso. Paint Inesfly 5A IGR™, comprised of two organophosphates (OPs) and an Insect Growth Regulator (IGR), was tested in combination with pyrethroid-treated LLINs. Efficacy was assessed in terms of mortality for 12 months using Early Morning Collections of malaria vectors and 30-minute WHO bioassays. Resistance to pyrethroids and OPs was assessed by detecting the frequency of L1014F and L1014S kdr mutation…