1,944 research outputs found
Il lessico storico come strumento di propaganda e di azione politica in Giappone
No full textLa Società per la creazione di un nuovo libro di testo di storia e il movimento del revisionismo storico in Giappone, dagli anni Novanta del Novecento.The Society for a New History Texbook and the hitorical revisionism in Japan from the late Nineties of Twentieth Century
ANALISI COMPARATIVA ULTRASTRUTTURALE DELLE GHIANDOLE RIPRODUTTIVE ACCESSORIE MASCHILI IN BACTROCERA OLEAE E CERATITIS CAPITATA (DIPTERA: TEPHRITIDAE)
No full textNotes on the biology and ethology of Luperomorpha xanthodera, a flea beetle recently introduced into Europe
No full textThe life cycle, host plants and damage caused by Luperomorpha xanthodera (Fairmaire), a chrysomelid recently introduced to
Europe, are described. In Tuscany (Italy) L. xanthodera completes 2 generations per year and all stages may overwinter in soil. Adults fly and feed from March-April until autumn. Females oviposit in the soil where larvae complete their development on radicles and pupate. Adults are polyphagous, chiefly anthophagous, causing damage on plants belonging to 23 genera of 19 botanical families
Comparative fine structural analysis of the male reproductive accessory glands in Bactrocera oleae and Ceratitis capitata (Diptera, Tephritidae)
No full textThe morphology and ultrastructure of the male reproductive accessory glands from Bactrocera oleae and Ceratitis capitata were comparatively investigated. In both insects, there are two types of glands, mesoderm- and ectoderm-derived, which open in the ejaculatory duct. The mesoderm-derived glands are sac-like in B. oleae and very long tubules in C. capitata, whereas the ectodermic glands, generally branched finger-like structures, are longer in B. oleae than in C. capitata. Despite their different morphology, the ultrastructure of the two types of glands is quite similar in both Tephritids. The epithelium of the mesoderm-derived glands consists of binucleate and microvillate secretory cells. In C. capitata, but not in B. oleae, the secretory cells contain smooth endoplasmic reticulum and, in the sexually mature males, enlarged polymorphic mitochondria. The gland lumen is filled with a dense or sometimes granulated secretion. The ectoderm-derived glands undergo a cycle of maturation, by which their epithelial cells form a large subcuticular cavity filled with an electrontransparent secretion. Electrophoretic analysis of accessory gland secretion reveals in both species the presence of low molecular weight protein bands. A major band of about 29 kDa or 30 kDa in B. oleae and C. capitata, respectively, is
revealed
Ultrastruttura delle ghiandole accessorie maschili di Ceratitis capitata (Wiedemann) e preliminare caratterizzazione del loro secreto
No full textFine structure of the male reproductive accessory glands of Ceratitis capitata (Wiedemann) and preliminary characterization of their secretion
The male reproductive accessory glands of the medfly Ceratitis capitata consist of two main different types of glands: one type is formed by long slender tubular glands of mesodermal origin; the second type by ectodermally derived short finger-like and/or branched structures with spongy appearance. Both these types of glands flow into a common chamber from which the ejaculatory duct prolongs.
The short glands show a huge subcuticular cavity surrounded by laminar cytoplasm provided with long and slender microvilli protruding into the cavity. An electron transparent secretion is present in the cavity from which it passes through minute pores of the cuticular intima and it is stored in the gland lumen. The secretion contains protein material.
The tubular glands show binucleated and microvillated cells rich in smooth endoplasmic reticulum and large polymorphic mitochondria. A secretion containing lipids flows into the narrow gland lumen
VIRTU' E BENE COMUNE
No full textIl testo riproduce una relazione tenuta dall’autore all’interno di un ciclo di seminari dedicato al concetto di “bene comune”, organizzato dall’Università di Perugia nel 2008. A una delineazione classica del “bene comune” fa seguito l’illustrazione essenziale di due prospettive non-classiche sul
tema : quella di Von Hayek e quella di Habermas. Ne emerge che le prospettive non -classiche del bene comune non costituiscono, a ben vedere, una alternativa, bensì una implementazione rispetto alla prospettiva classi ca. All’interno di quest’ultima, occorre evidenziare: l’irriducibilità del bene
comune al bene pubblico (con ciò che ne consegue), e l’insostituibilità delle comunità (familiari, religiose, lavorative, politiche) entro le quali si forma la persona umana e si trasmettono le virtù essenziali per il perseguimento di un bene riconoscibile e condivisibile da ognuno.
Altri autori: P. Daddi, P. Grasselli, M. Moschini, F. Valori, R. Vinerba, E. Lussana, M. Boccaccio, C. Montesi, G. Vittadini, F. Musotti, L. Bartocci, M. Signorelli, A. Montrone, M. Musella, I. Colozzi, A. Lombardi, F. Scaglione, L. Mezzasoma, G. Lizzi
Titolo: ß-N-acetylhexosaminidase activity in the female accessory gland secretion of fruit flies
No full textUltrastructure of the midgut and the adhering tubular salivary glands of Frankliniella occidentalis (Pergande)(Thysanoptera: Thripidae)
No full textThe ultrastructure of the midgut and the tubular salivary glands of Frankliniella occidentalis (Thysanoptera:Thripidae) is described. The microvilli have 2 different types of glycocalyx: in the anterior part of the midgut they are surrounded by a myelin-like membrane; in the posterior region, the microvilli have numerous rod-like projections arranged to form a continuous layer. Microfilaments longitudinally cross each microvillus; the microfilaments contain F-actin. Tubular salivary glands flank the midgut but do not fuse with it. The distal part of these glands have microvillated cells containing large amounts of electron-transparent material. The cells of the proximal part are lined with a thin cuticle
Functional morphology of the female reproductive apparatus of Stephanitis pyrioides (Heteroptera, Tingidae): a novel role for the pseudospermathecae
No full textAt mating, female insects generally receive and store sperm in specific organs of their reproductive tract called spermathecae. Some Heteroptera, such as Cimicomorpha, lack a true spermatheca; some have receptacles of novel formation where sperm cells can transit or be stored. In Tingidae, there are two sac-like diverticula, the "pseudospermathecae," each at the base of a lateral oviduct, which previously were considered to function as spermathecae. However, this role has never been documented, either by ultrastructural studies or by observations of sperm transit in the female reproductive tract. In this article, we investigate the morphology and the ultrastructure of the female reproductive apparatus in the economically important tingid species Stephanitis pyrioides, focusing our attention on the functional role of the pseudospermathecae in an evolutionary perspective. Each ovary consists of seven telotrophic meroistic ovarioles, the long pedicels of which enlarge into a bulb-like structure near the terminal oocyte. The ovarioles flow into two long lateral oviducts, which join to form a very short common oviduct. Basally, each lateral oviduct is connected through a short duct to one of two pseudospermathecae. The ultrastructure of the ectodermal epithelium of the pseudospermathecae is dramatically different in sexually immature or mated females. In virgin females, cells delimit a very irregular lumen, filled with a moderately electron-dense granular material. The large nucleus adapts to their irregular shape, which can have long projections in some regions and be flattened in others. After mating, epithelial cells generally elongate and display an apical layer of microvilli extending beneath the cuticle, often containing mitochondria. In the lumen of the pseudospermathecae there is a dense brownish secretion. No sperm cells were ever found inside this organ. After mating, sperm move upward along the lateral oviducts and the ovarioles, accumulating in the bulb-like structure of the pedicels, and proceeding into the distal region between the follicle cells surrounding the oocyte and the ovariole wall. The egg, most likely fertilized in the bulb-like region of the ovariole, moves through the lateral oviduct, entirely enters the pseudospermatheca and is smeared with its secretion just before oviposition. We exclude a function of sperm storage for the pseudospermathecae, and instead suggest a novel role for these organs as reproductive accessory glands
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