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On the discovery of some articles on history and development of physics connecting to Bruno Pontecorvo (French Period 1936–1939)
No full textDuring some research about the activity of the Physics Institute of the University of Pisa before the Second World War, some articles connecting to Bruno Pontecorvo, who was a collaborator of Enrico Fermi’s in via Panisperna
researches, came out. These articles were written by Pontecorvo under pseudonym and published in a Paris newspaper in the Italian language, in which many Italian
anti-Fascist refugees wrote, during the so-called “French period” (1936–1939), when Bruno Pontecorvo was a refugee in France. These articles regard various subjects, from M.me Curie’s discoveries and the artificial radioactivity to the nuclear fission, considering their possible applications to
Theoretical study for a 117mSn production experiment with a 30 MeV α-beam cyclotron
No full textMetastable 117mSn is a promising theranostic radionuclide, suitable for SPECT diagnostic imaging and conversion electron therapy. Its production is based mainly on nuclear reactors, but there is increasing interest in alternative routes with cyclotrons. Theoretical studies are essential to identify the irradiation parameters and conditions to maximize its production, while minimizing the impact of the contaminants. The goal of this study is to investigate the production of 117mSn with a 30 MeV α beam on natCd and natIn targets, as provided by the HIL-UW (Heavy Ion Laboratory - University of Warsaw) U-200P cyclotron. We performed a theoretical analysis of cross section, yield and purity by means of two nuclear reaction codes: Talys (v.1.9), based on a combination of models, and Fluka (v.2018.2.dev), based on Monte Carlo simulations. We compared the theoretical calculations with both experimental data already known in the literature and preliminary results obtained at HIL. A statistical treatment of the models suggests a comparable production of 117mSn for both targets, but a higher radionuclidic purity was found in the case of the natIn target
Electret ion chamber and environmental gamma radiation background: Preliminary results on the optimization of a radon gas measurement system
No full textA study to evaluate the feasibility of using a system routinely used for measurements of radon gas concentration for measuring the background of gamma radiation was carried out. This approach would reduce the employment of different detectors to a single type, standardizing the methodology adopted and reducing the costs affecting other types of detectors. A 1440 hours long measurement was
performed, using an experimental EIC system. The results were compared with measurements provided by a proportional counter and thermoluminescence dosimeters used as a reference. The results suggest the potential of the EIC system for unconventional use for gamma radiation background measurements
Popolazioni, epidemie e pandemie
Get PDFWith the covid-19 pandemic, the ghost of the plague has returned to frighten even the inhabitants of the rich and developed world, confident, until a few months ago, that the developments of medicine and of health systems would protect them from epidemics and pandemics. The history of mankind, however, is also made up of coexistence and, at times, of mutual adaptation with all those microorganisms and parasites that can be pathogenic. Among the most significant effects of the current pandemic there is also that of bringing attention back to the role that infectious diseases have played in the development of human populations. This is precisely the theme of this article, in which we tried to highlight some general aspects of the relationship between infectious diseases and demographic dynamics, then focusing attention on some specific cases in which the impact on the population has been particularly important
Conservazione dell’agrobiodiversità, sostenibilità per gli agricoltori e profili bioetici
Get PDFGuardandosi attorno si rimane colpiti dalla variegata percezione che la nostra società ha dell’agricoltura e
dell’agrobiodiversità. Da un lato molti consumatori ritengono che l’agricoltura moderna sia causa di numerosi mali: inquinamento dei suoli e del cibo, sottrazione di territori alla “naturalezza”, produzione di cibo malsano o addirittura fonte di malattie
Green Synthesis of Encapsulated Copper Nanoparticles Using a Hydroalcoholic Extract of Moringa oleifera Leaves and Assessment of Their Antioxidant and Antimicrobial Activities
No full textThe synthesis of metal nanoparticles using plant extracts is a very promising method in green synthesis. The medicinal value of Moringa oleifera leaves and the antimicrobial activity of metallic copper were combined in the present study to synthesize copper nanoparticles having a desirable added-value inorganic material. The use of a hydroalcoholic extract of M. oleifera leaves for the green synthesis of copper nanoparticles is an attractive method as it leads to the production of harmless chemicals and reduces waste. The total phenolic content in the M. oleifera leaves extract was 23.0 ± 0.3 mg gallic acid equivalent/g of dried M. oleifera leaves powder. The M. oleifera leaves extract was treated with a copper sulphate solution. A color change from brown to black indicates the formation of copper nanoparticles. Characterization of the synthesized copper nanoparticles was performed using ultraviolet-visible light (UV-Vis) spectrophotometry, Fourier-transform infrared (FTIR) spectrometry, high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The synthesized copper nanoparticles have an amorphous nature and particle size of 35.8-49.2 nm. We demonstrate that the M. oleifera leaves extract and the synthesized copper nanoparticles display considerable antioxidant activity. Moreover, the M. oleifera leaves extract and the synthesized copper nanoparticles exert considerable anti-bacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecalis (MIC values for the extract: 500, 250, 250, and 250 µg/mL; MIC values for the copper nanoparticles: 500, 500, 500, and 250 µg/mL, respectively). Similarly, the M. oleifera leaves extract and the synthesized copper nanoparticles exert relatively stronger anti-fungal activity against Aspergillus niger, Aspergillus flavus, Candida albicans, and Candida glabrata (MIC values for the extract: 62.5, 62.5, 125, and 250 µg/mL; MIC values for the copper nanoparticles: 125, 125, 62.5, and 31.2 µg/mL, respectively). Our study reveals that the green synthesis of copper nanoparticles using a hydroalcoholic extract of M. oleifera leaves was successful. In addition, the synthesized copper nanoparticles can be potentially employed in the treatment of various microbial infections due to their reported antioxidant, anti-bacterial, and anti-fungal activitie
Précarités socio-économiques, vulnerabilités et exploitations des mineures migrantes travailleuses dans le district de Abidjan et la ville de Grand-Bassam
Get PDFLa presente ricerca è stata svolta a Treichville e Port-Bouët nel Distretto di Abidjan e nella città di Grand-Bassam (Costa d’Avorio), territori che vedono la presenza di numerosi gruppi di popolazione di origine straniera. Essa si è posta l’obiettivo di analizzare l’impatto della vulnerabilità legata alla precarietà socioeconomica nell’ambito del fenomeno dello sfruttamento delle minori migranti lavoratrici. Si ritiene, come ipotesi di partenza, che la vulnerabilità legata alla precarietà socioeconomica possa spiegare lo sfruttamento delle minori migranti lavoratrici. Dal punto di vista metodologico, sono state utilizzate l’osservazione e l’intervista. I dati sono stati elaborati tramite l’analisi del contenuto al fine di riuscire a far emergere i principali punti di vista e analizzare il senso ed il significato dei differenti discorsi degli intervistati. I risultati di questo studio, di tipo qualitativo e quantitativo, riguardano principalmente i due seguenti ambiti: condizione di vulnerabilità legata alla precarietà sociale ed economica delle minorenni migranti; fenomeno dello sfruttamento delle minori migranti lavoratrici.
Cette étude s’est déroulée à Treichville et Port-Bouët dans le District d’Abidjan et dans la ville de Grand-Bassam, composés d’importantes populations d’origines étrangères. Elle vise à analyser l’impact de la vulnérabilité liée à la précarité socioéconomique sur l’exploitation des mineures migrantes travailleuses. L’hypothèse postule que la vulnérabilité liée à la précarité socioéconomique explique l’exploitation des mineures migrantes travailleuses. Au plan de la méthodologie, l’observation et l’entretien ont été utilisés. Le traitement des données s’est fait par l’analyse de contenu afin de pouvoir mieux cerner et analyser les sens et significations des différents discours des enquêtés. Les résultats de cette étude de type qualitatif et quantitatif portent sur deux points : description de la vulnérabilité liée à la précarité sociale et économique des mineures migrantes ; manifestation de l’exploitation des mineures migrantes travailleuses.
This study took place in Treichville and Port-Bouët in the District of Abidjan and in the city of Grand-Bassam, composed of large populations of foreign origins. It aims to analyze the impact of vulnerability linked to socioeconomic deprivation on the exploitation of working migrant minors. The hypothesis postulates that the vulnerability linked to the socioeconomic precariousness explains the exploitation of the minor migrant workers. In terms of methodology, observation and interview were used. Data processing was done through content analysis in order to better understand and analyze the meanings of the different speeches of the respondents. The results of this qualitative and quantitative study focus on two points: description of the vulnerability linked to the social and economic precariousness of minors; demonstration of the exploitation of working migrant minors
Fragile yet powerful. Rural landscape heritage as resource for inclusive and sustainable development in archaeological inhabited sites
Get PDFSri Ksetra, in Myanmar, is an inhabited archaeological area in which rural landscape, widespread built heritage and archaeological evidences are intertwined with presence of numerous villages. In 2014 the three Pyu cities were named as the first UNESCO World Heritage Site in Myanmar: despite the premises, Sri Ksetra, Beikthano and Halin were not listed as ‘cultural landscapes’ sites but recognized as ‘cultural’ sites. Field research in 2015 highlighted emerging issues in the management and safeguarding of inhabited archaeological sites. The investigation raises critical issues concerning the conservation and management of the rural landscape as heritage, in view of a sustainable development of the site in favour of those who live there
Settlement and viewshed dynamics between the ancient sites of the Erei as a key of historical landscape interpretation
Get PDFThe inner Sicilian area of the Erei hills, crossed by rivers and important streams directed to the Catania’s lowland, witnessed very ancient human occupation and activities, starting from the Upper Palaeolithic. Here the dynamics of human activities and the organization of the supply basin during early times were distinctive in certain historical periods: some featured a substantial continuity with the earlier phases, while others showed a complete discontinuity with the older human settlement framework and a new organization of the area and activities connected with the environment. These agricultural, proto-urban and urban communities organized their existence on the exploitation of natural resources, distributing themselves according to the local morphology. They built, mostly on top of the hills, constructions used as control viewpoints of the area, and created a complete communication network to connect settlements of the same or different level. Those features in several cases had a long-term continuity that survived to dramatic historical changes and represent today the optimal way for a right perception of current landscape and its millenary history
L’architetto, l’archeologo e Nostradamus
Get PDFWhen performing restoration work, it is not only the technical elements that come into play, but also social, economic and cultural aspects. This approach sees restoration as one continuous flow of ideas and operational plans, based on a fusion of disciplines and on collaboration between multiple players. These players, in various ways and for different motives, all take part in a restoration project, from diagnostics and planning to construction site management and even until the final result can be enjoyed by users, and they do so by constantly respecting the uniqueness of each individual situation. The collaborative relationships and partnerships formed on a restoration site foster a sense of belonging and mutual responsibility. The process of restoration may present a valuable opportunity for the community to come together, offering chances to raise cultural and civil awareness whilst encouraging people to collectively reflect on rediscovering and safeguarding local history. After all, a region may be embodied in a monument which the community can look to in order to identify and recognise themselves. The training of restoration architects is of particular importance in regions frequently affected by natural disasters or where local construction practices are being gradually left behind and traditional ways of living are undergoing radical transformation. If a restoration policy is to be considered conscientious and respectful of local communities, it must actively involve local people in restoration work. Attention should be paid to how these communities may dynamically evolve over time, as well as to the stresses and strains they are under. As such, projects must take account of a multitude of aspects: local cultures, the teaching of co-existence, the evolution of concepts regarding the conservation and restoration of historical and cultural sites and, finally, the remembrance and appreciation of traditions, as these traditions may be both unique and useful in imparting knowledge and providing first-hand evidence of traditional construction techniques