Search results for "Quine"
showing 10 items of 140 documents
Stratificazione ontologica e fluidità del reale
2013
The question of reality implies the necessity of declaring a principle of reality. Thus, it means the necessity of declaring a principle of existence. Through the adoption of a wide criterion like that of intentional existence following up on Quine’s accounts, the question is reformulated as a question concerning not what but how being is. Using Bauman’s concept of liquidity in an ontological manner and discussing Malabou’s notion of plasticity, the form as essence is seen in its possibility of being receptive and fluid and not ontologically static or stiff. Facing a stratified reality, we need to insert phenomenology and hermeneutics into metaphysics or rather rediscover the originary phen…
Zwitterionic codeine-derived methacrylate monoliths for enantioselective capillary electrochromatography of chiral acids and chiral bases
2018
Thiol-ene click reaction of N-acetyl-L-cysteine methyl ester to codeine, followed by reaction with allyl isocyanate and hydrolysis to the corresponding zwitterionic chiral selector and its subsequent bonding to the surface of a methacrylate monolith provided a new chiral capillary column for enantiomer separation of chiral acids and chiral bases. First, the epoxy groups of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith were converted into amine residues, followed by reaction with allylglycidyl ether. In this way, a spacer arm was bonded to the surface before coating and cross-linking poly(3-mercaptopropyl methylsiloxane) (PMPMS) via radical addition (thiol-ene click react…
Development of an improved method for trace analysis of quinolones in eggs of laying hens and wildlife species using molecularly imprinted polymers.
2012
A sensitive, selective, and efficient method was developed for simultaneous determination of 11 fluoroquinolones (FQs), ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, norfloxacin, ofloxacin, oxolinic acid, pipemidic acid, and sarafloxacin, in eggs by molecularly imprinted polymer (MIP) and column liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Samples were diluted with 50 mM sodium dihydrogen phosphate at pH 7.4, followed by purification with a commercial MIP (SupelMIP SPE-Fluoroquinolones). Recoveries for the 11 quinolones were in the range of 90-106% with intra- and interday relative standard deviation ranging from …
Joziknipholones A and B: The First Dimeric Phenylanthraquinones, from the Roots ofBulbine frutescens
2007
From the roots of the African plant Bulbine frutescens (Asphodelaceae), two unprecedented novel dimeric phenylanthraquinones, named joziknipholones A and B, possessing axial and centrochirality, were isolated, together with six known compounds. Structural elucidation of the new metabolites was achieved by spectroscopic and chiroptical methods, by reductive cleavage of the central bond between the monomeric phenylanthraquinone and -anthrone portions with sodium dithionite, and by quantum chemical CD calculations. Based on the recently revised absolute axial configuration of the parent phenylanthraquinones, knipholone and knipholone anthrone, the new dimers were attributed to possess the P-co…
Rotenoids, Flavonoids, and Chalcones from the Root Bark of Millettia usaramensis.
2015
Five new compounds, 4-O-geranylisoliquiritigenin (1), 12-dihydrousararotenoid B (2), 12-dihydrousararotenoid C (3), 4'-O-geranyl-7-hydroxyflavanone (4), and 4'-O-geranyl-7-hydroxydihydroflavanol (5), along with 12 known natural products (6-17) were isolated from the CH2Cl2/MeOH (1:1) extract of the root bark of Millettia usaramensis ssp. usaramensis by chromatographic separation. The purified metabolites were identified by NMR spectroscopic and mass spectrometric analyses, whereas their absolute configurations were established on the basis of chiroptical data and in some cases also by X-ray crystallography. The crude extract was moderately active (IC50 = 11.63 μg/mL) against the ER-negative…
Explaining the relationship between socially responsible products and the operations of the firm: The case of equine assisted therapy
2018
Abstract Although there is a growing interest in social responsibility in research as well as in practice, the majority of studies on corporate social responsibility do not explicitly investigate operations management issues when adopting socially responsible practices under the “people” pillar of sustainability. This paper, dealing with the theme of social responsibility in operations management, aims at clarifying the complex relationship between socially responsible product/service and the operations of the company. The empirical context of the study is the sport industry, where the attention to social issues is well established. We used a mixed theoretical-empirical approach to develop …
Presentation of insulin and insulin A chain peptides to mouse T cells: involvement of cysteine residues.
1991
The requirements for insulin presentation and recognition by A alpha b A beta b- and A alpha b A beta k-restricted mouse T cells were studied using a variety of derivatives of the insulin A chain. It was found that A chain peptides with irreversibly blocked Cys residues are non-stimulatory for the T cells. This suggests that at least one of the Cys residues is essential for recognition. On the other hand, all A chain peptides containing Cys residues modified in a way reversible by reaction with thiols are stimulatory yet differ in antigenic potency. All these A chain derivatives including a 14 amino acid fragment require uptake by antigen presenting cells (APC) for efficient presentation. D…
El sentit de l'ontologia en W. V. O. Quine
2004
El corrent positivista va conèixer molt aviat els seus heterodoxos. L'heterodòxia consistia fonamentalment en el fet de no acceptar la tesi de la reducció de la filosofia a l'anàlisi logicosintàctica del llenguatge i en el de ser reticents al rebuig dogmàtic dc l'especulació filosòfica. Bertrand Russell ja clamà al seu dia en defensa de l'especulació filosòfica i contra el dogmatisme positivista. I Quine fou un dels primers. filòsofs que, tot i que contaminat de positivisme però híbrid de positivisme i russellianisme, va obrir les portes a l'ontologia.
Compromís òntic i relativitat ontològica
2004
La major part dels escrits filosòfics del professor Quine menen a l'ontologia, entesa com una resposta a la qüestió «sobre el que hi ha». La tradició metafísica ha situat la investigació ontològica en un context de justificació: es tractava d'esbrinar per què hi havia boscos en compte de deserts desolats. El tomb que Quine dóna a l'ontologia consisteix a plantejar-se una qüestió prèvia i a ajustar els termes del plantejament. La qüestió «què és el que hi ba?» se situa en un context de decisió -«decisió òntica», ha estat anomenada per Quine- més que no en un context de justificació. Aquesta distinció marca ja el sentit de la resposta: quan es tractava de justificar el que hi ha, calia recórr…
EQUINE ASSISTED LEARNING: SYMBOLIC VALUE OF HORSE AS UNDERLYING PATTERN IN HUMAN THINKING
2018
Traditional pedagogy do not stressed the unique and challenging needs of the adult learner for a different kind of educational experience that was more engaging, more flexible and more appreciative of the existing knowledge base and experience of the adult learning. Equine Assisted Learning is a practice in which adults engage in systematic and sustained self–educating activities in order to gain new forms of knowledge, skills, attitudes, or values. The purpose of this research is to illustrate the meaning and symbolic value of horse as underlying pattern in human thinking.