1,238 research outputs found
Bevande: permeabilità agli aromi di materiali plastici.
No full textL'articolo prende in esame le problematiche legate alla misura della permeabilità agli aromi dei polimeri plastici e tratta anche alcuni aspetti teorici del fenomen
Is autotopoagnosia real? EC says yes. A case study
No full textWe report a case of pure autotopagnosia (AT) following a left subcortical vascular accident. The absence of any language disorder, general mental deterioration or other cognitive impairments in this patient allowed an in-depth study of AT. Several tests of body representation and object and animal representation, as well as tests assessing semantic skills were administered to verify current interpretations of AT. Results showed a clear-cut dissociation between defective performances in body representation tests and normal performances on tests involving other kinds of stimuli. The patient's performances were particularly defective on tests relying on visuo-spatial body representation. but her semantic and linguistic knowledge seemed to he spared. This dissociation between different aspects of body representation supports Sirigu et al.'s hypothesis that multiple, partially independent systems are involved in body knowledge. In agreement with this hypothesis, in the present patient AT seems be due to a deficit in a system that processes the structural properties and relative position of single body parts. The present results, reporting the first observation Of a subject not affected by any cognitive impairment other than AT, strongly support the existence of a system specifically devoted to body representation. (C) 2002 Elsevier Science Ltd. All rights reserved
Production in Escherichia coli of recombinant COVID-19 spike protein fragments fused to CRM197
No full textDuring 2020, the COVID-19 pandemic affected almost 108 individuals. Quite a number of vaccines against COVID-19 were therefore developed, and a few recently received authorization for emergency use. Overall, these vaccines target specific viral proteins by antibodies whose synthesis is directly elicited or indirectly triggered by nucleic acids coding for the desired targets. Among these targets, the receptor binding domain (RBD) of COVID-19 spike protein (SP) does frequently occur in the repertoire of candidate vaccines. However, the immunogenicity of RBD per se is limited by its low molecular mass, and by a structural rearrangement of full-length SP accompanied by the detachment of RBD. Here we show that the RBD of COVID-19 SP can be conveniently produced in Escherichia coli when fused to a fragment of CRM197, a variant of diphtheria toxin currently used for a number of conjugated vaccines. In particular, we show that the CRM197-RBD chimera solubilized from inclusion bodies can be refolded and purified to a state featuring the 5 native disulphide bonds of the parental proteins, the competence in binding angiotensin-converting enzyme 2, and a satisfactory stability at room temperature. Accordingly, our observations provide compulsory information for the development of a candidate vaccine directed against COVID-19
Study of aroma and polymer interactions.
No full textThe diffusional properties of polymeric packaging materials are strictly related to the shelf-life of packaged food products and the use and demand of high barrier polymers in food packaging applications are growing in importance. High barrier polymers are generally defined in terms of oxygen and water vapour barrier, considered to be detrimental of the food quality. However, among the components participating in externally-driven degradative reactions, volatile flavours and aroma compounds are neglected. Whereas permeability data and standardised measuring procedures are available for gases and water vapour, information on flavours and other organic compounds are limited.
Several studies have been made about the absorption of aroma compounds from citrus juice (G.Pieper et al, 1992; J. Letinsky and G. W. Halek, 1992; G. D. Sadler and R. J. Braddock, 1991), showing a reduction of d-limonene of up to 50% by adsorption into LDPE inside coating packaging (G. Pieper et al., 1992) and many permeations studies have been made too.
Permeability’s phenomena can be represented into three steps: first we have a sorption of the molecules on the surface of the film, than the molecules diffuse into the film and finally they can desorbe from the other side of the film. Generally, for a gas permeant, permeability is described as: P=D*S , where “S” is the solubility coefficient and “D” the diffusion coefficient. If this equation can describe appropriately the permeation of permanent gases, on the contrary, if organic vapors are concerned, it does not satisfy, because of: “P” and “S” are temperature-dependent and the value obtained from this equation are good for gases that do not interact between them and that do not produce structural changes into the polymer. As demonstrated by Togawa et al. (X), the d-limonene, generally used as a model permeant, is absorbed into the polyolefin films inducing a swelling and a structural changing, which contribute to the characteristic permeability enhancement of volatile compounds.
Aim of this work was to study and evaluate the phenomena of permeability and adsorption of three different aroma compounds in a biaxially oriented polypropylene and in a two biaxially oriented polypropylene-based materials modified, one with TiO2 and the other one expanded.
The aroma were tested individually and in a mixture for all the different materials, in order to investigate the interaction’s effect of more than one compounds
Fresh fruit and vegetables: a world of multiple interactions : the case of the Buenos Aires Central Wholesale Market (BACWM)
No full textThis research explores ethnographically the everyday social interactions between the ‘users’ of a particular marketplace, the Buenos Aires Central Wholesale Market (BACWM). The ‘users’ of this marketplace are the social actors who work there everyday, and who bring and buy fresh produce. These ´users´ are the ´makers´ of the BACWM since, through their everyday practices, interactions and interpretations and knowledge, they socially construct this hub of distribution
A Laboratory for Mathematics
No full textMacchine matematiche; dalla storia alla scuola is a book by Maria Grazia Bartolini Bussi and Michela Maschietto that provides a description of the reconstruction of many
historical machines for drawing, and their impact on the history of mathematics. Underlying the book’s thesis are ideas about
education and developments in neuroscience. Laura Tedeschini Lalli discussed the book and the educational experiments and
their goals with author Maria Grazia Bartolini Bussi
Representações sociais em estudantes trabalhadores
No full textOrientador: Maria Laura Puglisi Barbosa FrancoDissertação (mestrado)-Universidade Estadual de Campinas, Faculdade de EducaçãoMestradoPsicologia EducacionalMestre em Educaçã
Maria Cristina Arellana, Georgina Estevez, and Laura Tobie
No full textThis 1965 photograph shows Maria Cristina Arellana of Havana, Cuba, Georgina Estevez and Laura Tobie, both of Caracas, Venezuela in Hubert Hayes Memorial Log Cabin. Founder and director of the Mountain Youth Jamboree, Hubert H. Hayes (1901-1964) auditioned and directed youth to perform in folk dance, music, and folk and ballad singing. The jamboree was held in the Asheville City Auditorium (now known as Thomas Wolfe Auditorium) from 1948 to 1973, and Hayes’ wife, Leona Trantham Hayes (1913-1989) continued to direct the program after his death in 1964. Hubert Hayes was an author, playwright, and alumni of Duke University
Il prosciutto cotto quale sistema modello per lo studio della previsione della shelf-life.
No full textNella presente ricerca si è inteso valutare comealcune tecniche di conservazione possanoincidere sull’evoluzione della complessiva del prosciutto cotto, scelto qualesistema modello per lo studio della inprodotti alimentari non restrittivi per la crescitadei microrganismi. Predire la shelf-life delprosciutto cotto affettato risulta molto difficilein quanto la contaminazione casuale dopo lacottura e le condizioni igieniche delle zonedi affettamento e confezionamento rendonol’intero sistema estremamente aleatorio. Nellaricerca effettuata, i campioni di prosciutto sonostati inoculati con microrganismi specifici dialterazione precedentemente isolati da prosciuttocotto alterato. In una seconda prova sono statiimpiegati trattamenti con azoto allo stesso finedi diminuire l’aleatorietà del sistema dovuta allacontaminazione casuale
Role of different factors affecting the formation of 5-hydroxymethyl-2-furancarboxaldehyde in heated grape must
No full textThe influence of concentration and water activity (aw) on the formation of 5-hydroxymethyl-2-furancarboxaldehyde (HMF) in thermally treated grape must was evaluated. Must was cryoconcentratedand then heated to study the pure effect of sugar concentration. Moreover, NaCl was addedto the must to lower aw, maintaining the same sugar concentration, with the purpose of evaluatingthe pure effect of aw. Finally, the influence of minimal pH changes on the formation of HMF wasevaluated by means of a model solution. The results showed that aw and sugar concentration areboth determinant in the formation of HMF in grape must. Sugar concentration influences the reactionby supplying substrates; low aw enhances the formation of HMF by changing the equilibrium in thedehydration step of the reaction
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