An integrated course of study in general science for the three consecutive grades in the junior high schools of a small industrial city

Thesis (M.A.)--Boston University, 1947. This item was digitized by the Internet Archive

Efficient stem cell isolation from under vacuum preserved tissue samples

Different approaches for the isolation of stem/progenitor cells have been reported, including stem cell selection in stringent culture conditions. We evaluated the possibility of isolating human progenitor cells from surgical specimens preserved by under vacuum sealing and cooling, a clinical practice approached by several hospitals as alternative to formalin. Renal tissue samples (n = 20) maintained under vacuum from 6 to 48 h at 4°C were used to isolate human renal CD133(+) progenitor cells. We obtained CD133(+) progenitors from unsorted cells derived from disaggregated tissues from each sample. Phenotypic characterization as well as in vitro and in vivo differentiation of the obtained CD133(+) lines showed results comparable with sorted CD133(+) cells obtained from fresh tissue. These results indicate that the process of sealing under vacuum and cooling appears as a suitable tissue treatment to isolate hypoxia resistant cells, such as human stem/progenitor cells, and that this procedure can be exploited to render the extraction of stem cells from human samples more practical and feasible

Oracoli e sogni regali tra Antico Egitto e Vicino Oriente

Analisi della pratica oracolare in ambito regale, dall'inizio del II millennio all'inizio del I millennio a.C., attraverso lo studio delle testimonianze testuali di ambito egiziano e vicino orientale. Le finalità della tesi sono state quelle di evidenziare le differenze e le eventuali coincidenze riguardo alla modalità della pratica nei due mondi

Design and experimentation of communication and of a teaching sequence on atmospheric physics

Weather and climate are topical issues widely present in the media, in the public culture, in political and socio-economic agendas and also in school guidelines. Having said that, confusion and a lot of misconceptions still exist with regards to issues such as climate change, greenhouse gases and the greenhouse effect, pollution, anthropogenic emissions, ozone hole, predictability of weather and climate, stationary processes, radiation fluxes and balances in the Earth system etc. These themes are poorly addressed in the actual teaching practice in secondary schools, particularly from a quantitative point of view involving the underlying laws of physics, which are necessary for the understanding and construction of correct conceptual models of phenomena. Teachers often do not feel comfortable or lack the specific background for addressing such themes quantitatively, claiming for training initiatives which happen unfortunately only as a result of sporadic and local initiatives. For historical reasons, typical of the Italian context, these themes are usually addressed in subjects like geography or natural sciences for what concerns education in formal contexts such as primary and secondary schools and universities, but their treatment and significance would greatly benefit from an interdisciplinary approach, involving also the quantitative experimental approach of physics. At the same time, teaching physics from its general principles to their application in the context of weather phenomena and climate system, would improve the engagement and interest of students, fostering cooperation among teachers of different subjects, bridging boundaries and approaches characteristic of single disciplines. This would promote an integrated view of science as the result of a process, based on the application of the scientific method to the investigation and modeling of phenomena, where also technological advancement plays an important role, rather than as a mere collection of results and knowledge. In this perspective the present work develops from the research in atmospheric physics, performed by the candidate during one year at Concordia station, Antarctica, presenting on one hand a series of physics communication initiatives designed and tested with innovative formats such as TEDx conferences, videoconferences with researchers working on the field, social platforms and traditional media, targeted to different audiences. On the other hand it presents the proposal of a teaching learning sequence based on quantitative experimental activities, demonstrations and simulations, targeted to secondary school students and pre-service teachers, integrating general physics with its applications to the atmosphere and to the climate system. The teaching learning sequence has been experimented with graduate students of the course: ''Experimental physics laboratory at high school I'', held at the Department of Physics of the University of Trento and in collaboration with IPRASE, it has been proposed in the form of a training course for physics and chemistry teachers and their technical assistants as a framework for the integration of physics and chemistry. The results of pre and post tests used as an evaluation tool of this preliminary experimentation will be presented, encouraging future developments of the sequence and further diffusion of weather and climate issues in the teaching practice through capillary pre-teachers' and teachers' training initiatives

A new LC-MS/MS method for simultaneous and quantitative detection of bisphenol-a and steroids in target tissues: A power tool to characterize the interference of bisphenol-a exposure on steroid levels

Bisphenol A (BPA), an endocrine disruptor, may affect in situ steroidogenesis and alter steroids levels. The present work proposes a liquid chromatography tandem mass spectrometry method to simultaneously quantify BPA, 17β-Estradiol and testosterone in two target tissues: testis and visceral fat mass. Analytes were isolated and lipophilic impurities removed by two serial steps: liquid-liquid and solid phase extraction. All compounds were separated in a single gradient run by Kinetex F5 column and detected via multiple reaction monitoring using a triple quadrupole with a TurboIon electrospray source in both negative and positive modes. The method is selective and very sensitive. In the investigated concentration range, the linearity of the detector response is verified in both tissues. The use of specific SPE cartridges for affinity chromatography purification allows obtaining high percentages of process efficiency (68.0-83.3% for testicular tissue; 63.7-70.7% for visceral fat mass). Good repeatability and reproducibility was observed. The validated method can be efficiently applied for direct biological monitoring in testis and visceral fat mass from mice exposed to BPA. The quantification of compounds in a single assay could be achieved without a loss of sensitivity

UNIGE_SE @ PRELEARN: Utility for Automatic Prerequisite Learning from Italian Wikipedia

The present paper describes the approach proposed by the UNIGE_SE team to tackle the EVALITA 2020 shared task on Prerequisite Relation Learning (PRELEARN). We developed a neural network classifier that exploits features extracted both from raw text and the structure of the Wikipedia pages provided by task organisers as training sets. We participated in all four sub–tasks proposed by task organizers: the neural network was trained on different sets of features for each of the two training settings (i.e., raw and structured features) and evaluated in all proposed scenarios (i.e. in– and cross– domain). When evaluated on the official test sets, the system was able to get improvements compared to the provided baselines, even though it ranked third (out of three participants). This contribution also describes the interface we developed to compare multiple runs of our models