6 resultados para Life Change Events

em AMS Tesi di Dottorato - Alm@DL - Università di Bologna


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This research aims at investigating the impact of the identity change on consumption. An identity change is defined as the acquisition of a new identity after a life change event. For instance after the birth of the first child the new identity as parent is acquired and a woman can define herself as a mother. Despite marketing research recognizes that individuals’ identity is unstable and susceptible to change, the investigation of the identity change is still in its infancy. Furthermore, marketing research did not investigate the contextual effect of the new as well as the old identity on individuals’ reaction toward identity-marketing. In order words, whether people show a more favorable reaction toward product related to their new or their old identities after an identity change is still unclear. In order to answer this question, five studies are conducted. Results show that when the new identity substitutes the old one, people show a more positive reaction toward new-identity related products, while when the new identity is added to the old ones, people show a more positive reaction toward old-identity related products. This is the case also when the new identity accounts for high levels of identification (study three) and when the old identity is squeezed by the new one (studies four and five). A new concept, the identity strain, is then introduced and discussed.

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This volume is a collection of the work done in a three years-lasting PhD, focused in the analysis of Central and Southern Adriatic marine sediments, deriving from the collection of a borehole and many cores, achieved thanks to the good seismic-stratigraphic knowledge of the study area. The work was made out within European projects EC-EURODELTA (coordinated by Fabio Trincardi, ISMAR-CNR), EC-EUROSTRATAFORM (coordinated by Phil P. E. Weaver, NOC, UK), and PROMESS1 (coordinated by Serge Bernè, IFREMER, France). The analysed sedimentary successions presented highly expanded stratigraphic intervals, particularly for the last 400 kyr, 60 kyr and 6 kyr BP. These three different time-intervals resulted in a tri-partition of the PhD thesis. The study consisted of the analysis of planktic and benthic foraminifers’ assemblages (more than 560 samples analysed), as well as in preparing the material for oxygen and carbon stable isotope analyses, and interpreting and discussing the obtained dataset. The chronologic framework of the last 400 kyr was achieved for borehole PRAD1-2 (within the work-package WP6 of PROMESS1 project), collected in 186.5 m water depth. The proposed chronology derives from a multi-disciplinary approach, consisting of the integration of numerous and independent proxies, some of which analysed by other specialists within the project. The final framework based on: micropaleontology (calcareous nannofossils and foraminifers’ bioevents), climatic cyclicity (foraminifers’ assemblages), geochemistry (oxygen stable isotope, made out on planktic and benthic records), paleomagnetism, radiometric ages (14C AMS), teprhochronology, identification of sapropel-equivalent levels (Se). It’s worth to note the good consistency between the oxygen stable isotope curve obtained for borehole PRAD1-2 and other deeper Mediterranean records. The studied proxies allowed the recognition of all the isotopic intervals from MIS10 to MIS1 in PRAD1-2 record, and the base of the borehole has been ascribed to the early MIS11. Glacial and interglacial intervals identified in the Central Adriatic record have been analysed in detail for the paleo-environmental reconstruction, as well. For instance, glacial stages MIS6, MIS8 and MIS10 present peculiar foraminifers’ assemblages, composed by benthic species typical of polar regions and no longer living in the Central Adriatic nowadays. Moreover, a deepening trend in the paleo-bathymetry during glacial intervals was observed, from MIS10 (inner-shelf environment) to MIS4 (mid-shelf environment).Ten sapropel-equivalent levels have been recognised in PRAD1-2 Central Adriatic record. They showed different planktic foraminifers’ assemblages, which allowed the first distinction of events occurred during warm-climate (Se5, Se7), cold-climate (Se4, Se6 and Se8) and temperate-intermediate-climate (Se1, Se3, Se9, Se’, Se10) conditions, consistently with literature. Cold-climate sapropel equivalents are characterised by the absence of an oligotrophic phase, whereas warm-temeprate-climate sapropel equivalents present both the oligotrophic and the eutrophic phases (except for Se1). Sea floor conditions vary, according to benthic foraminifers’ assemblages, from relatively well oxygenated (Se1, Se3), to dysoxic (Se9, Se’, Se10), to highly dysoxic (Se4, Se6, Se8) to events during which benthic foraminifers are absent (Se5, Se7). These two latter levels are also characterised by the lamination of the sediment, feature never observed in literature in such shallow records. The enhanced stratification of the water column during the events Se8, Se7, Se6, Se5, Se4, and the concurring strong dilution of shallow water, pointed out by the isotope record, lead to the hypothesis of a period of intense precipitation in the Central Adriatic region, possibly due to a northward shift of the African Monsoon. Finally, the expression of Central Adriatic PRAD1-2 Se5 equivalent was compared with the same event, as registered in other Eastern Mediterranean areas. The sequence of substantially the same planktic foraminifers’ bioevents has been consistently recognised, indicating a similar evolution of the water column all over the Eastern Mediterranean; yet, the synchronism of these events cannot be demonstrated. A high resolution analysis of late Holocene (last 6000 years BP) climate change was carried out for the Adriatic area, through the recognition of planktic and benthic foraminifers’ bioevents. In particular, peaks of planktic Globigerinoides sacculifer (four during the last 5500 years BP in the most expanded core) have been interpreted, based on the ecological requirements of this species, as warm-climate, arid intervals, correspondent to periods of relative climatic optimum, such as, for instance, the Medieval Warm Period, the Roman Age, the Late Bronze Age and the Copper Age. Consequently, the minima in the abundance of this biomarker could correspond to relatively cooler and more rainy periods. These conclusions are in good agreement with the isotopic and the pollen data. The Last Occurrence (LO) of G. sacculifer has been dated in this work at an average age of 550 years BP, and it is the best bioevent approximating the base of the Little Ice Age in the Adriatic. Recent literature reports the same bioevent in the Levantine Basin, showing a rather consistent age. Therefore, the LO of G. sacculifer has the potential to be extended to all the Eastern Mediterranean. Within the Little Ice Age, benthic foraminifer V. complanata shows two distinct peaks in the shallower Adriatic cores analysed, collected hundred kilometres apart, inside the mud belt environment. Based on the ecological requirements of this species, these two peaks have been interpreted as the more intense (cold and rainy) oscillations inside the LIA. The chronologic framework of the analysed cores is robust, being based on several range-finding 14C AMS ages, on estimates of the secular variation of the magnetic field, on geochemical estimates of the activity depth of 210Pb short-lived radionuclide (for the core-top ages), and is in good agreement with tephrochronologic, pollen and foraminiferal data. The intra-holocenic climate oscillations find out in the Adriatic have been compared with those pointed out in literature from other records of the Northern Hemisphere, and the chronologic constraint seems quite good. Finally, the sedimentary successions analysed allowed the review and the update of the foraminifers’ ecobiostratigraphy available from literature for the Adriatic region, thanks to the achievement of 16 ecobiozones for the last 60 kyr BP. Some bioevents are restricted to the Central Adriatic (for instance the LO of benthic Hyalinea balthica , approximating the MIS3/MIS2 boundary), others occur all over the Adriatic basin (for instance the LO of planktic Globorotalia inflata during MIS3, individuating Dansgaard-Oeschger cycle 8 (Denekamp)).

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The ideal approach for the long term treatment of intestinal disorders, such as inflammatory bowel disease (IBD), is represented by a safe and well tolerated therapy able to reduce mucosal inflammation and maintain homeostasis of the intestinal microbiota. A combined therapy with antimicrobial agents, to reduce antigenic load, and immunomodulators, to ameliorate the dysregulated responses, followed by probiotic supplementation has been proposed. Because of the complementary mechanisms of action of antibiotics and probiotics, a combined therapeutic approach would give advantages in terms of enlargement of the antimicrobial spectrum, due to the barrier effect of probiotic bacteria, and limitation of some side effects of traditional chemiotherapy (i.e. indiscriminate decrease of aggressive and protective intestinal bacteria, altered absorption of nutrient elements, allergic and inflammatory reactions). Rifaximin (4-deoxy-4’-methylpyrido[1’,2’-1,2]imidazo[5,4-c]rifamycin SV) is a product of synthesis experiments designed to modify the parent compound, rifamycin, in order to achieve low gastrointestinal absorption while retaining good antibacterial activity. Both experimental and clinical pharmacology clearly show that this compound is a non systemic antibiotic with a broad spectrum of antibacterial action, covering Gram-positive and Gram-negative organisms, both aerobes and anaerobes. Being virtually non absorbed, its bioavailability within the gastrointestinal tract is rather high with intraluminal and faecal drug concentrations that largely exceed the MIC values observed in vitro against a wide range of pathogenic microorganisms. The gastrointestinal tract represents therefore the primary therapeutic target and gastrointestinal infections the main indication. The little value of rifaximin outside the enteric area minimizes both antimicrobial resistance and systemic adverse events. Fermented dairy products enriched with probiotic bacteria have developed into one of the most successful categories of functional foods. Probiotics are defined as “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host” (FAO/WHO, 2002), and mainly include Lactobacillus and Bifidobacterium species. Probiotic bacteria exert a direct effect on the intestinal microbiota of the host and contribute to organoleptic, rheological and nutritional properties of food. Administration of pharmaceutical probiotic formula has been associated with therapeutic effects in treatment of diarrhoea, constipation, flatulence, enteropathogens colonization, gastroenteritis, hypercholesterolemia, IBD, such as ulcerative colitis (UC), Crohn’s disease, pouchitis and irritable bowel syndrome. Prerequisites for probiotics are to be effective and safe. The characteristics of an effective probiotic for gastrointestinal tract disorders are tolerance to upper gastrointestinal environment (resistance to digestion by enteric or pancreatic enzymes, gastric acid and bile), adhesion on intestinal surface to lengthen the retention time, ability to prevent the adherence, establishment and/or replication of pathogens, production of antimicrobial substances, degradation of toxic catabolites by bacterial detoxifying enzymatic activities, and modulation of the host immune responses. This study was carried out using a validated three-stage fermentative continuous system and it is aimed to investigate the effect of rifaximin on the colonic microbial flora of a healthy individual, in terms of bacterial composition and production of fermentative metabolic end products. Moreover, this is the first study that investigates in vitro the impact of the simultaneous administration of the antibiotic rifaximin and the probiotic B. lactis BI07 on the intestinal microbiota. Bacterial groups of interest were evaluated using culture-based methods and molecular culture-independent techniques (FISH, PCR-DGGE). Metabolic outputs in terms of SCFA profiles were determined by HPLC analysis. Collected data demonstrated that rifaximin as well as antibiotic and probiotic treatment did not change drastically the intestinal microflora, whereas bacteria belonging to Bifidobacterium and Lactobacillus significantly increase over the course of the treatment, suggesting a spontaneous upsurge of rifaximin resistance. These results are in agreement with a previous study, in which it has been demonstrated that rifaximin administration in patients with UC, affects the host with minor variations of the intestinal microflora, and that the microbiota is restored over a wash-out period. In particular, several Bifidobacterium rifaximin resistant mutants could be isolated during the antibiotic treatment, but they disappeared after the antibiotic suspension. Furthermore, bacteria belonging to Atopobium spp. and E. rectale/Clostridium cluster XIVa increased significantly after rifaximin and probiotic treatment. Atopobium genus and E. rectale/Clostridium cluster XIVa are saccharolytic, butyrate-producing bacteria, and for these characteristics they are widely considered health-promoting microorganisms. The absence of major variations in the intestinal microflora of a healthy individual and the significant increase in probiotic and health-promoting bacteria concentrations support the rationale of the administration of rifaximin as efficacious and non-dysbiosis promoting therapy and suggest the efficacy of an antibiotic/probiotic combined treatment in several gut pathologies, such as IBD. To assess the use of an antibiotic/probiotic combination for clinical management of intestinal disorders, genetic, proteomic and physiologic approaches were employed to elucidate molecular mechanisms determining rifaximin resistance in Bifidobacterium, and the expected interactions occurring in the gut between these bacteria and the drug. The ability of an antimicrobial agent to select resistance is a relevant factor that affects its usefulness and may diminish its useful life. Rifaximin resistance phenotype was easily acquired by all bifidobacteria analyzed [type strains of the most representative intestinal bifidobacterial species (B. infantis, B. breve, B. longum, B. adolescentis and B. bifidum) and three bifidobacteria included in a pharmaceutical probiotic preparation (B. lactis BI07, B. breve BBSF and B. longum BL04)] and persisted for more than 400 bacterial generations in the absence of selective pressure. Exclusion of any reversion phenomenon suggested two hypotheses: (i) stable and immobile genetic elements encode resistance; (ii) the drug moiety does not act as an inducer of the resistance phenotype, but enables selection of resistant mutants. Since point mutations in rpoB have been indicated as representing the principal factor determining rifampicin resistance in E. coli and M. tuberculosis, whether a similar mechanism also occurs in Bifidobacterium was verified. The analysis of a 129 bp rpoB core region of several wild-type and resistant bifidobacteria revealed five different types of miss-sense mutations in codons 513, 516, 522 and 529. Position 529 was a novel mutation site, not previously described, and position 522 appeared interesting for both the double point substitutions and the heterogeneous profile of nucleotide changes. The sequence heterogeneity of codon 522 in Bifidobacterium leads to hypothesize an indirect role of its encoded amino acid in the binding with the rifaximin moiety. These results demonstrated the chromosomal nature of rifaximin resistance in Bifidobacterium, minimizing risk factors for horizontal transmission of resistance elements between intestinal microbial species. Further proteomic and physiologic investigations were carried out using B. lactis BI07, component of a pharmaceutical probiotic preparation, as a model strain. The choice of this strain was determined based on the following elements: (i) B. lactis BI07 is able to survive and persist in the gut; (ii) a proteomic overview of this strain has been recently reported. The involvement of metabolic changes associated with rifaximin resistance was investigated by proteomic analysis performed with two-dimensional electrophoresis and mass spectrometry. Comparative proteomic mapping of BI07-wt and BI07-res revealed that most differences in protein expression patterns were genetically encoded rather than induced by antibiotic exposure. In particular, rifaximin resistance phenotype was characterized by increased expression levels of stress proteins. Overexpression of stress proteins was expected, as they represent a common non specific response by bacteria when stimulated by different shock conditions, including exposure to toxic agents like heavy metals, oxidants, acids, bile salts and antibiotics. Also, positive transcription regulators were found to be overexpressed in BI07-res, suggesting that bacteria could activate compensatory mechanisms to assist the transcription process in the presence of RNA polymerase inhibitors. Other differences in expression profiles were related to proteins involved in central metabolism; these modifications suggest metabolic disadvantages of resistant mutants in comparison with sensitive bifidobacteria in the gut environment, without selective pressure, explaining their disappearance from faeces of patients with UC after interruption of antibiotic treatment. The differences observed between BI07-wt e BI07-res proteomic patterns, as well as the high frequency of silent mutations reported for resistant mutants of Bifidobacterium could be the consequences of an increased mutation rate, mechanism which may lead to persistence of resistant bacteria in the population. However, the in vivo disappearance of resistant mutants in absence of selective pressure, allows excluding the upsurge of compensatory mutations without loss of resistance. Furthermore, the proteomic characterization of the resistant phenotype suggests that rifaximin resistance is associated with a reduced bacterial fitness in B. lactis BI07-res, supporting the hypothesis of a biological cost of antibiotic resistance in Bifidobacterium. The hypothesis of rifaximin inactivation by bacterial enzymatic activities was verified by using liquid chromatography coupled with tandem mass spectrometry. Neither chemical modifications nor degradation derivatives of the rifaximin moiety were detected. The exclusion of a biodegradation pattern for the drug was further supported by the quantitative recovery in BI07-res culture fractions of the total rifaximin amount (100 μg/ml) added to the culture medium. To confirm the main role of the mutation on the β chain of RNA polymerase in rifaximin resistance acquisition, transcription activity of crude enzymatic extracts of BI07-res cells was evaluated. Although the inhibition effects of rifaximin on in vitro transcription were definitely higher for BI07-wt than for BI07-res, a partial resistance of the mutated RNA polymerase at rifaximin concentrations > 10 μg/ml was supposed, on the basis of the calculated differences in inhibition percentages between BI07-wt and BI07-res. By considering the resistance of entire BI07-res cells to rifaximin concentrations > 100 μg/ml, supplementary resistance mechanisms may take place in vivo. A barrier for the rifaximin uptake in BI07-res cells was suggested in this study, on the basis of the major portion of the antibiotic found to be bound to the cellular pellet respect to the portion recovered in the cellular lysate. Related to this finding, a resistance mechanism involving changes of membrane permeability was supposed. A previous study supports this hypothesis, demonstrating the involvement of surface properties and permeability in natural resistance to rifampicin in mycobacteria, isolated from cases of human infection, which possessed a rifampicin-susceptible RNA polymerase. To understand the mechanism of membrane barrier, variations in percentage of saturated and unsaturated FAs and their methylation products in BI07-wt and BI07-res membranes were investigated. While saturated FAs confer rigidity to membrane and resistance to stress agents, such as antibiotics, a high level of lipid unsaturation is associated with high fluidity and susceptibility to stresses. Thus, the higher percentage of saturated FAs during the stationary phase of BI07-res could represent a defence mechanism of mutant cells to prevent the antibiotic uptake. Furthermore, the increase of CFAs such as dihydrosterculic acid during the stationary phase of BI07-res suggests that this CFA could be more suitable than its isomer lactobacillic acid to interact with and prevent the penetration of exogenous molecules including rifaximin. Finally, the impact of rifaximin on immune regulatory functions of the gut was evaluated. It has been suggested a potential anti-inflammatory effect of rifaximin, with reduced secretion of IFN-γ in a rodent model of colitis. Analogously, it has been reported a significant decrease in IL-8, MCP-1, MCP-3 e IL-10 levels in patients affected by pouchitis, treated with a combined therapy of rifaximin and ciprofloxacin. Since rifaximin enables in vivo and in vitro selection of Bifidobacterium resistant mutants with high frequency, the immunomodulation activities of rifaximin associated with a B. lactis resistant mutant were also taken into account. Data obtained from PBMC stimulation experiments suggest the following conclusions: (i) rifaximin does not exert any effect on production of IL-1β, IL-6 and IL-10, whereas it weakly stimulates production of TNF-α; (ii) B. lactis appears as a good inducer of IL-1β, IL-6 and TNF-α; (iii) combination of BI07-res and rifaximin exhibits a lower stimulation effect than BI07-res alone, especially for IL-6. These results confirm the potential anti-inflammatory effect of rifaximin, and are in agreement with several studies that report a transient pro-inflammatory response associated with probiotic administration. The understanding of the molecular factors determining rifaximin resistance in the genus Bifidobacterium assumes an applicative significance at pharmaceutical and medical level, as it represents the scientific basis to justify the simultaneous use of the antibiotic rifaximin and probiotic bifidobacteria in the clinical treatment of intestinal disorders.

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«In altri termini mi sfuggiva e ancora oggi mi sfugge gran parte del significato dell’evoluzione del tempo; come se il tempo fosse una materia che osservo dall’esterno. Questa mancanza di evoluzione è fonte di alcune mie sventure ma anche mi appartiene con gioia.» Aldo Rossi, Autobiografia scientifica. The temporal dimension underpinning the draft of Autobiografia scientifica by Aldo Rossi may be referred to what Lucien Lévy-Bruhl, the well-known French anthropologist, defines as “primitive mentality” and “prelogical” conscience : the book of life has lost its page numbers, even punctuation. For Lévy-Bruhl, but certainly for Rossi, life or its summing up becomes a continuous account of ellipses, gaps, repetitions that may be read from left to right or viceversa, from head to foot or viceversa without distinction. Rossi’s autobiographical writing seems to accept and support the confusion with which memories have been collected, recording them after the order memory gives them in the mental distillation or simply according to the chronological order in which they have happened. For Rossi, the confusion reflects the melting of memory elements into a composite image which is the result of a fusion. He is aware that the same sap pervades all memories he is going to put in order: each of them has got a common denominator. Differences have diminished, almost faded; the quick glance is prevalent over the distinction of each episode. Rossi’s writing is beyond the categories dependent on time: past and present, before and now. For Rossi, the only repetition – the repetition the text will make possible for an indefinite number of times – gives peculiarity to the event. As Gilles Deleuze knows, “things” may only last as “singleness”: more frequent the repetition is, more singular is the memory phenomenon that recurs, because only what is singular magnifies itself and happens endlessly forever. Rossi understands that “to raise the first time to nth forever”, repetition becomes glorification . It may be an autobiography that, celebrating the originality, enhances the memory event in the repetition; in fact it greatly differs from the biographical reproduction, in which each repetition is but a weaker echo, a duller copy, provided with a smaller an smaller power in comparison with the original. Paradoxically, for Deleuze the repetition asserts the originality and singularity of what is repeated. Rossi seems to share the thought expressed by Kierkegaard in the essay Repetition: «The hope is a graceful maiden slipping through your fingers; the memory of an elderly woman, indeed pretty, but never satisfactory if necessary; the repetition is a loved friend you are never tired of, as it is only the new to make you bored. The old never bores you and its presence makes you happy [...] life is but a repetition [...] here is the beauty of life» . Rossi knows well that repetition hints at the lasting stability of cosmic time. Kierkegaard goes on: «The world exists, and it exists as a repetition» . Rossi devotes himself, on purpose and in all conscience, to collect, to inventory and «to review life», his own life, according to a recovery not from the past but of the past: a search work, the «recherche du temps perdu», as Proust entitled his masterpiece on memory. If you want the past time to be not wasted, you must give it presence. «Memoria e specifico come caratteristiche per riconoscere se stesso e ciò che è estraneo mi sembravano le più chiare condizioni e spiegazioni della realtà. Non esiste uno specifico senza memoria, e una memoria che non provenga da un momento specifico; e solo questa unione permette la conoscenza della propria individualità e del contrario (self e non-self)» . Rossi wants to understand himself, his own character; it is really his own character that requires to be understood, to increase its own introspective ability and intelligence. «Può sembrare strano che Planck e Dante associno la loro ricerca scientifica e autobiografica con la morte; una morte che è in qualche modo continuazione di energia. In realtà, in ogni artista o tecnico, il principio della continuazione dell’energia si mescola con la ricerca della felicità e della morte» . The eschatological incipit of Rossi’s autobiography refers to Freud’s thought in the exact circularity of Dante’s framework and in as much exact circularity of the statement of the principle of the conservation of energy: in fact it was Freud to connect repetition to death. For Freud, the desire of repetition is an instinct rooted in biology. The primary aim of such an instinct would be to restore a previous condition, so that the repeated history represents a part of the past (even if concealed) and, relieving the removal, reduces anguish and tension. So, Freud ask himself, what is the most remote state to which the instinct, through the repetition, wants to go back? It is a pre-vital condition, inorganic of the pure entropy, a not-to-be condition in which doesn’t exist any tension; in other words, Death. Rossi, with the theme of death, introduces the theme of circularity which further on refers to the sense of continuity in transformation or, in the opposite way, the transformation in continuity. «[...] la descrizione e il rilievo delle forme antiche permettevano una continuità altrimenti irripetibile, permettevano anche una trasformazione, una volta che la vita fosse fermata in forme precise» . Rossi’s attitude seems to hint at the reflection on time and – in a broad sense – at the thought on life and things expressed by T.S. Eliot in Four Quartets: «Time present and time past / Are both perhaps present in time future, / And time future is contained in time past. / I all time is eternally present / All time is unredeemable. / What might have been is an abstraction / Remaining perpetual possibility / Only in a word of speculation. / What might have been and what has been / Point to one end, which is always present. [...]» . Aldo Rossi’s autobiographical story coincides with the description of “things” and the description of himself through the things in the exact parallel with craft or art. He seems to get all things made by man to coincide with the personal or artistic story, with the consequent immediate necessity of formulating a new interpretation: the flow of things has never met a total stop; all that exists nowadays is but a repetition or a variant of something existing some time ago and so on, without any interruption until the early dawnings of human life. Nevertheless, Rossi must operate specific subdivisions inside the continuous connection in time – of his time – even if limited by a present beginning and end of his own existence. This artist, as an “historian” of himself and his own life – as an auto-biographer – enjoys the privilege to be able to decide if and how to operate the cutting in a certain point rather than in another one, without being compelled to justify his choice. In this sense, his story is a matter very ductile and flexible: a good story-teller can choose any moment to start a certain sequence of events. Yet, Rossi is aware that, beyond the mere narration, there is the problem to identify in history - his own personal story – those flakings where a clean cut enables the separation of events of different nature. In order to do it, he has to make not only an inventory of his own “things”, but also to appeal to authority of the Divina Commedia started by Dante when he was 30. «A trent’anni si deve compiere o iniziare qualcosa di definitivo e fare i conti con la propria formazione» . For Rossi, the poet performs his authority not only in the text, but also in his will of setting out on a mystical journey and handing it down through an exact descriptive will. Rossi turns not only to the authority of poetry, but also evokes the authority of science with Max Plank and his Scientific Autobiography, published, in Italian translation, by Einaudi, 1956. Concerning Planck, Rossi resumes an element seemingly secondary in hit account where the German physicist «[...] risale alle scoperte della fisica moderna ritrovando l’impressione che gli fece l’enunciazione del principio di conservazione dell’energia; [...]» . It is again the act of describing that links Rossi to Planck, it is the description of a circularity, the one of conservation of energy, which endorses Rossi’s autobiographical speech looking for both happiness and death. Rossi seems to agree perfectly to the thought of Planck at the opening of his own autobiography: «The decision to devote myself to science was a direct consequence of a discovery which was never ceased to arouse my enthusiasm since my early youth: the laws of human thought coincide with the ones governing the sequences of the impressions we receive from the world surrounding us, so that the mere logic can enable us to penetrate into the latter one’s mechanism. It is essential that the outer world is something independent of man, something absolute. The search of the laws dealing with this absolute seems to me the highest scientific aim in life» . For Rossi the survey of his own life represents a way to change the events into experiences, to concentrate the emotion and group them in meaningful plots: «It seems, as one becomes older. / That the past has another pattern, and ceases to be a mere sequence [...]» Eliot wrote in Four Quartet, which are a meditation on time, old age and memory . And he goes on: «We had the experience but missed the meaning, / And approach to the meaning restores the experience / In a different form, beyond any meaning [...]» . Rossi restores in his autobiography – but not only in it – the most ancient sense of memory, aware that for at least 15 centuries the Latin word memoria was used to show the activity of bringing back images to mind: the psychology of memory, which starts with Aristotele (De Anima), used to consider such a faculty totally essential to mind. Keith Basso writes: «The thought materializes in the form of “images”» . Rossi knows well – as Aristotele said – that if you do not have a collection of mental images to remember – imagination – there is no thought at all. According to this psychological tradition, what today we conventionally call “memory” is but a way of imagining created by time. Rossi, entering consciously this stream of thought, passing through the Renaissance ars memoriae to reach us gives a great importance to the word and assumes it as a real place, much more than a recollection, even more than a production and an emotional elaboration of images.

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Tracking activities during daily life and assessing movement parameters is essential for complementing the information gathered in confined environments such as clinical and physical activity laboratories for the assessment of mobility. Inertial measurement units (IMUs) are used as to monitor the motion of human movement for prolonged periods of time and without space limitations. The focus in this study was to provide a robust, low-cost and an unobtrusive solution for evaluating human motion using a single IMU. First part of the study focused on monitoring and classification of the daily life activities. A simple method that analyses the variations in signal was developed to distinguish two types of activity intervals: active and inactive. Neural classifier was used to classify active intervals; the angle with respect to gravity was used to classify inactive intervals. Second part of the study focused on extraction of gait parameters using a single inertial measurement unit (IMU) attached to the pelvis. Two complementary methods were proposed for gait parameters estimation. First method was a wavelet based method developed for the estimation of gait events. Second method was developed for estimating step and stride length during level walking using the estimations of the previous method. A special integration algorithm was extended to operate on each gait cycle using a specially designed Kalman filter. The developed methods were also applied on various scenarios. Activity monitoring method was used in a PRIN’07 project to assess the mobility levels of individuals living in a urban area. The same method was applied on volleyball players to analyze the fitness levels of them by monitoring their daily life activities. The methods proposed in these studies provided a simple, unobtrusive and low-cost solution for monitoring and assessing activities outside of controlled environments.

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The latter part of the 20th century was a period characterized by a fundamental demographic transition of western society. This substantial and structural demographic change proposes several challenges to contemporary society and fosters the emergence of new issues and challenges. Among these, none is more crucial than the comprehension of the mechanisms and the processes that lead people to positive aging. Rowe and Kahn’s model of successful aging highlights the interplay between social engagement with life, health, and functioning for a positive aging experience. Other systemic models of successful aging (Kahana et al., 1996; 2003; Stevernik et al., 2006) emphasize the role of internal and external resources for attaining positive aging. Among these, the proactive coping strategies are indicated as important active strategies for avoiding the depletion of resources, counterbalancing the declines and maintaining social and civic involvement. The study has analyzed the role of proactive coping strategies for two facets of positive aging, the experience of a high social well-being and the presence of personal projects in fundamental life domains. As expected, the proactive coping strategies, referred to as the active management of the environment, the accumulation of resources and the actualization of human potentials are confirmed as positive predictors of high level of social well-being and of many personal projects focused on family, culture, leisure time, civic and social participation. Perceived health status give a significant contribution only to the possession of many personal projects. Gender and level of school education give also a significant contribution to these two dimensions of positive aging, highlighting how positive aging is rooted not only in the possession of personal resources, but also in historical models of education and in positive longitudinal chains related to early development.