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Despite intensive efforts in recent decades to develop preventive or therapeutic vaccines against diseases caused by herpes simplex virus (HSV), or varicella-zoster virus (VZV), members of the Alpha herpes virinae subfamily of human herpes viruses,a safe and efficient vaccine has been approved for commercial development only against VZV. The VZV vaccine contains a live attenuated strain, OKA. It consists of amixture of at least 13 subpopulations of viruses, all with deletions, insertions or mutations in the genome; the most common mutations are observed in the open reading frame 62 (ORF62). Experience over more than 30 years in Japan, the USA and other countries where VZV vaccination is provided has demonstrated that the vaccine is safe and the effectiveness of two doses compared to unvaccinated children is 98–99%. When administered in a higher dose to stimulate the declining cell-mediated immunity, the same vaccine has been shown to reduce the incidence and severity of herpes zoster in immunocompetent individuals older than 60 years. Vaccination of immuno-compromised subjects with this VZV vaccine is problematic and various strategies need to be explored. Differences in the pathomechanisms of infection, latency and immune evasion of VZV and HSV, together with host genetic factors, may explain the availability of the successful VZV vaccine and the failures of the past HSV vaccine candidates.

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The thermal decomposition kinetics of sterically hindered salen type ligand (L) and its metal complexes [M=Co(II), Ni(II), Cu(II)] were investigated by thermogravimetric analysis. A direct insertion probe-mass spectrometer (DIP-MS) was used for the characterization of metal complexes of L and all fragmentations and stable ions were characterized. The thermogravimetry and differential thermogravimetry (TG-DTG) plots of salen type salicylaldimine ligand and complexes showed a single step. The kinetic analysis of thermogravimetric data was performed by using the invariant kinetic parameter method (IKP). The values of the invariant activation energy, E inv and the invariant pre-exponential factor, A inv, were calculated by using Coats-Redfern (CR) method. The thermal stabilities and activation energies of metal complexes of sterically hindered salen type ligand (L) were found as Co(II)>Cu(II)>Ni(II)>L and E Cu>E Ni>E Co>L. Also, the probabilities of decomposition functions were investigated. The diffusion functions (D n) are most probable for the thermal decomposition of all complexes.

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Part of a research program on cultural heritage aimed to elucidate the production of ceramic artifacts in Roman Pavia is devoted to the localization of the possible sources of raw materials (claypits) as well as to the technological production processes. Clay samples were collected in two different areas nearby Pavia, Lomellina and Oltrepo. Some of these samples were also fired at 950 °C. Archaeological ceramic samples, mostly bricks and tiles of Roman age, were obtained from excavations of Roman settlings close to Pavia. All samples were submitted to instrumental neutron activation analysis for the determination of Ca, Fe and a number of trace elements. Results indicate (1) fired and raw clay samples keep the same elemental fingerprint so that only raw samples data can be used in archaeometric studies; (2) some parameters based on rare earth elements are useful to discriminate the clay samples from the two investigated areas; (3) clay discrimination is confirmed also by discriminant analysis; and (4) the insertion of the elemental composition data of the ceramic artifacts in the statistical treatment allows one to assign the artifacts to one of the investigated areas and confirms that, at Roman times, the production of ceramic building materials was mostly based on the use of local prime matter.

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Post-operative biliary tract injuries have traditionally been treated by surgery; since the 1990s, however, this was replaced by endoscopic methods. These complications occur most frequently after laparoscopic surgery. Whenever biliary leakage is suspected, a close cooperation between endoscopists and surgeons is essential. Immediate visualisation of the biliary tract by endoscopic retrograde cholangio-pancreatography (ERCP) is mandatory to confi rm the diagnosis and locate the exact site of the lesion. Various endoscopic techniques have proven to be effective in the treatment of post-cholecystectomy biliary leaks. The crucial point is to equalise duodenal and biliary tract pressures so that bile fl ow into the duodenum is ensured and healing of the lesion is facilitated. This can be achieved by endoscopic sphincterotomy either alone or in combination with subsequent implantation of a plastic stent. These methods seem to be equally suitable; for greater lesions, however, insertion of a stent is advisable. For biliary tract strictures, multiple stenting is recommended, the results of which are promising in the long run as well.

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‘Altered recapitulations,’ commonly regarded as a distinguishing feature of Joseph Haydn’s sonata form movements, are usually explained in terms of the ‘monothematic’ design of the exposition. According to the logic used in such analytical studies, recomposing the recapitulation would have been aimed at restoring the proportional balance between exposition and recapitulation, a need that resulted from the omission of the seemingly redundant, retransposed secondary theme along with the preceding transition. Though such an explanation has long been considered indisputable, this article casts doubt on the validity of the redundancy principle by showing that Haydn often did retain the monothematic section in the recapitulation. Rather, the recomposition of the recapitulation results from two important structural aspects thus far largely neglected in the literature: (1) the repetitive formal structure of the main theme, which is often considerably reworked in the recapitulation; and (2) the insertion of a separate newly composed dominant zone in the recapitulation that serves to compensate for the lack of a structural dominant at the end of the development section. Finally, it is argued here that Haydn, who was deeply rooted in the late Baroque tradition, by no means regarded multiple ‘double returns’ as either problematic or redundant, for he may have been thinking more in terms of an overriding ritornello structure.

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L’imaginaire fantastique chez Nodier et l’inspiration biblique

Thématiques des images littéraires d’inspiration biblique reprises par Nodier

Neohelicon
Author: Graciela Boruszko

Résumé  

Cette article interroge sur l’utilisation des images bibliques au sein de l’œuvre de Charles Nodier, pionnier du conte fantastique en France. D’après une approche comparée les images bibliques originales sont confrontées avec les images transposées au sein du récit fantastique. L’analyse s’intéresse à la conjonction entre narration, emprunt des images bibliques et le résultat de cet emprunt dans une image modifiée qui fait référence à l’image original tout en participant dans un nouveau réseau de signification. L’intertextualité des emprunts témoigne d’une créativité littéraire qui s’exprime dans une nouvelle cosmogonie fantastique qui n’hésite pas à se servir d’un monde biblique afin de façonner une nouvelle interprétation du surnaturel.

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It is shown that insertion in methacrylic polymers of bulky electron donor/acceptor side-groups with taper-shaped flourinated tails promotes a self-organization of the respective side-chain polymers due to the space demands of the bulky D/A side-groups, leading to a columnar hexagonal mesophase. The presence of an Lc-phase is evidenced by DSC and identified by X-ray analysis. The orientation in the respective copolymers and polymer blends is additionally improved by the CT-interaction between the D/A side-groups. An increased packing effect due to this CT-orientation effect is evidenced in DSC by an increase of the respective transition temperatures. CT-interaction is responsible as well for a preferential polymerization of monomeric D/A-complexes leading to copolymers of alternating structures and for a zip-like arrangement along the main chain of the A/D-complexes between the interacting side-groups in polymer blends. Formation of mesophases is even observed in CT-interacting blends between the Lc-D/A side-chain polymethacrylates and the respective amorphous D/A side-chain polysiloxanes.

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The crystallization behaviour and the physical characterization of supramolecular complexes formed between permethylated-α-cyclodextrin (TMα-CD) and the enantiomers of phenylethanol (PE) are investigated. According to crystal structure analyses, complexes containing the pure guest enantiomers are almost isomorphous, indicating that the host presents a poor ability to distinguish PE enantiomers at a molecular level. Nevertheless, crystallizations from racemic PE in water induce an efficient chiral discrimination and allow the enantio-separation of the guests despite the existence of a solid solution revealed by XRPD and coupled TG-DSC analyses. The enantiodifferentiation is explained by solubility differences between the two diastereomeric complexes in the studied temperature range. Moreover, it is shown that the diastereomeric complex TMα-CD/(S)-PE crystallizes in two distinct phases: a monohydrate and an anhydrous form, with a transition temperature close to 37C. The insertion of a water molecule in the crystals grown below 37C does not involve any other change of the crystal packing nor of the molecular conformation, but leads to different crystal growth mechanisms inducing different morphologies and distinct thermal behaviours.

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Density and heat capacity of the water+cyclodextrin (CD), water+nicotinic acid (NA) and water+CD+NA mixtures were determined at 298.15 K. CDs with different cavity size and alkylation were selected. From the experimental data the apparent molar properties were calculated. Assuming the formation of inclusion complexes of 1:1 stoichiometry, these properties were modeled and provided the stability constants of CD/NA inclusion complexes and the corresponding property change. The binding of NA with the smallest sized α-cyclodextrin (α-CD) generates more stable complexes accompanied by the lower volume and the heat capacity changes. These results are in agreement with earlier proposed binding mode according to which deep insertion of NA into α-CD takes place and it is governed by the hydrophobic-hydrophilic forces. The volume and the heat capacity changes caused by the interactions of CDs with NA were interpreted in terms of cosphere overlap model and the release of water molecules from the CD cavity due to the NA incorporation.

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Das Ziel dieses Beitrags ist, funktional relevante morphosyntaktische Eigenschaften der ungarischen Infinitiv-Hilfsverb-Konstruktionen aufgrund korpusbasierter Untersuchungen aufzudecken, und diese als Gesichtspunkte zu einer Hilfsverbtypologie zu verwenden. Dazu wurden der ikonische Einschub von Hilfsverben zwischen Präfix und Infinitiv, die Frequenz der Verben sowie die Merkmalhaftigkeit/Merkmallosigkeit der Prädikatsnomina als Hauptkriterien untersucht. Aufgrund der Analyseergebnisse zeichnen sich zwei Typen von Infinitiv regierenden Hilfsverben ab, mit jeweils kontinuierlichen Übergängen ineinander und in andere Infinitiv regierende Konstruktionstypen.

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