13,141 research outputs found
Luigi Pacinotti (1807-1889) professore di Fisica all'Università di Pisa
No full textLe rare biografie su Luigi Pacinotti ne tracciano la vita e l'opera in poche righe e di lui non vi è traccia neppure su diverse enciclopedie importanti. L'articolo più ampio (14 pagine) su Luigi è a firma di Sebastiano Timpanaro (1888-1949) che lo scrisse durante la sua direzione della Domus Galilaeana a Pisa negli anni '40, avendo a disposizione l'Archivio Pacinotti sistemato da Giovanni Polvani (1892-1970) una quindicina di anni avanti . Inoltre in tutti questi pochi e brevi scritti mancano le indicazioni alle fonti primarie, sulle quali invece si è particolarmente focalizzato questo lavoro di ricerca con l'intento di porre su basi solide il racconto della vita del professor Luigi Pacinotti e della sua attività didattico-scientifica svolta per mezzo secolo - dal 1831 al 1882 - all'interno dell'Università pisana.
Per la ricostruzione della vita di Pacinotti sono risultati essenziali i documenti dell'Archivio Arcidiocesano di Pisa, dell'Archivio Diocesano di Pistoia, dell'Archivio di Stato di Pistoia, dell'Archivio della Parrocchia di San Sisto di Pisa e dell'Archivio di Villa Pacinotti di Caloria (Pt), mentre per le sue attività hanno contribuito molto i materiali dell'Archivio di Stato di Pisa, dell'Archivio Pacinotti e dell'Archivio del Liceo Classico Forteguerri di Pistoia.
Molte le trascrizioni di documenti presenti in questa tesi, in particolare di quelli redatti dallo stesso Luigi, la cui scrittura chiara, semplice e diretta risulta molto più efficace di qualsiasi commento o riassunto. Comunque, per non appesantire troppo la lettura la maggior parte delle trascrizioni e delle citazioni è stata inserita alla fine di ogni capitolo in un'appendice dedicata. La tesi inizia con l'attività didattica del nostro professore per poi passare alla biografia e infine alla ricerca, all'interno della quale ho ritenuto importante presentare per intero tutte le sue pubblicazioni, con un'attenzione specifica ai 4 volumi del Corso di Fisica Tecnologica e Meccanica Sperimentale: si tratta del primo elenco completo e corretto delle pubblicazioni di Luigi Pacinotti. Molti degli strumenti utilizzati da Luigi fortunatamente si sono conservati fino ai nostri giorni presso l'Università di Pisa e costituiscono un patrimonio inestimabile per la storia della scienza e della tecnologia; alcuni di questi strumenti vengono descritti nell'appendice B e messi a confronto con i disegni presenti sulle pubblicazioni dello stesso Pacinotti.
Il ritratto di Luigi che scaturisce da questo lavoro di tesi è quello di una persona legata fortemente alla famiglia, radicata nel territorio dove vive e lavora, e con ottime capacità intellettive e pratiche. Sin da ragazzo, non ancora laureato, pensò a trovarsi un lavoro vincendo la cattedra per l'insegnamento di matematica presso il Collegio Forteguerri di Pistoia che aveva precedentemente frequentato, e poi, oltre a laurearsi in Scienze matematiche, si laureò anche in Legge e iniziò a fare pratica in uno studio legale per poter avviare la carriera di procuratore; alla fine però fu la strada della scienza che percorse per il resto della sua vita. Il suo matrimonio con la contessina Caterina Catanti di Calci (PI) portò alla nascita di 11 figli, dei quali il primogenito fu il famoso Antonio Pacinotti. Per i documenti consultati il legame più forte sembra lo abbia avuto proprio con Antonio ma non è da escludere che fosse legato allo stesso modo anche agli altri. In certe sue lettere, in cui parla con e dei suoi figli, traspare un atteggiamento di padre premuroso, che indirizza i figli, li favorisce nello loro scelte, consigliandoli continuamente ma senza imporre la propria volontà. Anche nella lettura del testamento si ritrova questo senso di amore filiale di Luigi per tutti i figli in maniera indistinta.
La sua attività presso l'Università di Pisa, iniziata alla cattedra di Fisica Sperimentale, fu incessante; egli si prodigò per migliorare la dotazione degli strumenti, acquistandoli in Italia e all'estero o facendoli costruire direttamente da tecnici pisani, fiorentini e anche bolognesi (quando il figlio Antonio insegnava all'Istituto Tecnico Piercrescenzi di Bologna) e molto si diede da fare per sistemare i locali che gli vennero assegnati per il Gabinetto. Non da meno fu la sua opera per dar vita al nuovo Gabinetto di Fisica Tecnologica, che inizialmente raccolse gli strumenti meno importanti del Gabinetto di Fisica passato sotto la direzione di Carlo Matteucci, ma che con il passare del tempo si riempì di nuova strumentazione e aumentò lo spazio disponibile andando ad occupare alcune stanze del nuovo Istituto di Fisica fatto costruire proprio dal Matteucci nel 1844. Alla cura del Gabinetto scientifico Luigi non fece mancare neanche lo studio teorico dei fenomeni, come dimostrano alcune sue pubblicazioni, e per tener vivi i suoi studi nei primi anni '40 partecipò settimanalmente a delle conversazioni scientifiche che, probabilmente, si tenevano in casa sua dopo cena e forse erano state istituite per sua iniziativa.
Nel tempo i suoi studi lo resero un'autorità indiscussa nel campo di varie problematiche tecniche, in particolare di quelle legate al territorio; ad esempio lo si consultava o lo si chiamava a partecipare a commissioni quando si volevano risolvere problemi inerenti a fiumi e torrenti della pianura fra Pisa e Firenze, oppure si richiedeva il suo parere per un impianto a gas da costruire per la città di Pisa. Il corso di Fisica Tecnologica, che tenne per circa 40 anni, lo portò ad essere, oltre che fisico, anche un po' ingegnere idraulico ed edile; d'altra parte gli argomenti che trattava a lezione erano essenzialmente basi di fisica, di idraulica e di edilizia e l'introduzione della Fisica Tecnologica come materia di insegnamento, operata con la riforma Giorgini nel 1840, era stata pensata proprio per la formazione di ingegneri.
Nonostante il suo ottimo insegnamento cinquantennale, diverse pubblicazioni e un'intensa attività sul territorio, di Luigi non si è scritto nè parlato molto, probabilmente perché il nome dei Pacinotti da tutti è da sempre associato alla Macchinetta, la prima dinamo a corrente continua, e quindi al nome di Antonio Pacinotti, il suo primogenito. Spero che questo mio lavoro possa contribuire a sollecitare nuovi studi su questo importante professore di Fisica, troppo a lungo dimenticato
The impact of PISA in Portugal through the media
No full textO PISA (Programme for International Student Assessment) tem constituído um instrumento de ação da OCDE com impacto público e influência nas políticas de educação de diversos países. Este artigo analisa a forma como o PISA e a divulgação dos resultados dos alunos portugueses foram tratados em três meios nacionais de referência de comunicação escrita entre 2001 e 2012: o jornal Diário de Notícias, o jornal semanário Expresso e a revista semanal Visão. Concluiu-se que cada vez mais os media nacionais têm vindo a desempenhar um importante papel na divulgação dos resultados do PISA, com um aumento significativo do número de peças jornalísticas, contribuindo para moldar a política de educação nacional, ao estabelecerem frequentemente relação entre o PISA e medidas de política concretas em que este programa aparece como elemento legitimador da decisão.info:eu-repo/semantics/publishedVersio
IHTT report on Pisa - 2022
No full textThis article explains the purpose of the decision of the Cabinet of Ministers of the Republic of Uzbekistan No. 997 of December 8, 2018 “On measures to organize international studies in the field of education quality assessment in the public education system”, PISA - 2022 the results and the content of the tasks presented in it are highlighted. A sample assignment is also provided
IHTT report on Pisa - 2022
No full textThis article explains the purpose of the decision of the Cabinet of Ministers of the Republic of Uzbekistan No. 997 of December 8, 2018 “On measures to organize international studies in the field of education quality assessment in the public education system”, PISA - 2022 the results and the content of the tasks presented in it are highlighted. A sample assignment is also provided
PISA: Models and the reality
Get PDFThe Programme for International Student Assessment – PISA – is the most ambitious endeavour of
large-scale education systems evaluation ever implemented. The Organization for Economic Cooperation and Development – OECD – launched this exercise for the first time in 2000, and in the
2012 edition 65 education systems were assessed. According to OECD, the programme “[…] is a
triennial international survey which aims to evaluate education systems worldwide by testing skills and knowledge of 15-year-old students.” And, “[…] tests are designed to assess to what extent students at the end of compulsory education, can apply their knowledge to real-life situations and be equipped for full participation in society.”
Albeit being a prestigious programme, entrenched in sound theoretical grounds, and notwithstanding all the efforts made by PISA experts to mitigate shortcomings, the PISA is not exempt from criticisms of various kinds. When analysing the quotes mentioned above, and taking into consideration the applied methodologies, several questions can be raised and some concerns should be pointed out.
The first question arising in the process of evaluation is that any measurement always affects, direct or indirectly, the system itself, disturbing its inner workings. This fact is particularly relevant when social systems are at stake.
A second difficulty results when students from very different countries in what regards culture,
tradition, and beliefs are subjected to the same test. Although all items are always carefully analysed
by panels of experts in order to detect cultural bias or offending interpretations, there is no complete
guarantee that the final set of items is adequate to evaluate all students.
Another question regarding the fairness of PISA results is the fact that a paper-and-pencil (or
computer) test, limited to three disciplinary domains, cannot encompass the possibly rich, diverse, and unsuspected knowledge and skills of 15-year-old students.
There are also technical criticisms regarding the adopted approaches and methodologies, from the
utilization of the Rasch model to negative remarks about the way data are collected and questions are coded.
Some of what could be considered advantages of PISA – the literacy based instead of a curriculum
based approach, the assessment of 15-year-old students instead of a particular school year pupils,
and the definition of a large set of indicators, as is the case of ESCS – have been also severely criticised.
Finally, some of the criticisms reside, not in the PISA methods and characteristics themselves but on
an excessive focus on country rankings, primarily promoted by media, and consequently followed by
political leaders.
The main objective of this research is to reframe difficulties and artefacts together with virtuous results of PISA, putting in perspective praises and criticisms to foster a better understanding of this important programme.info:eu-repo/semantics/publishedVersio
PISA: Models and the reality
Get PDFThe Programme for International Student Assessment – PISA – is the most ambitious endeavour of
large-scale education systems evaluation ever implemented. The Organization for Economic Cooperation and Development – OECD – launched this exercise for the first time in 2000, and in the
2012 edition 65 education systems were assessed. According to OECD, the programme “[…] is a
triennial international survey which aims to evaluate education systems worldwide by testing skills and knowledge of 15-year-old students.” And, “[…] tests are designed to assess to what extent students at the end of compulsory education, can apply their knowledge to real-life situations and be equipped for full participation in society.”
Albeit being a prestigious programme, entrenched in sound theoretical grounds, and notwithstanding all the efforts made by PISA experts to mitigate shortcomings, the PISA is not exempt from criticisms of various kinds. When analysing the quotes mentioned above, and taking into consideration the applied methodologies, several questions can be raised and some concerns should be pointed out.
The first question arising in the process of evaluation is that any measurement always affects, direct or indirectly, the system itself, disturbing its inner workings. This fact is particularly relevant when social systems are at stake.
A second difficulty results when students from very different countries in what regards culture,
tradition, and beliefs are subjected to the same test. Although all items are always carefully analysed
by panels of experts in order to detect cultural bias or offending interpretations, there is no complete
guarantee that the final set of items is adequate to evaluate all students.
Another question regarding the fairness of PISA results is the fact that a paper-and-pencil (or
computer) test, limited to three disciplinary domains, cannot encompass the possibly rich, diverse, and unsuspected knowledge and skills of 15-year-old students.
There are also technical criticisms regarding the adopted approaches and methodologies, from the
utilization of the Rasch model to negative remarks about the way data are collected and questions are coded.
Some of what could be considered advantages of PISA – the literacy based instead of a curriculum
based approach, the assessment of 15-year-old students instead of a particular school year pupils,
and the definition of a large set of indicators, as is the case of ESCS – have been also severely criticised.
Finally, some of the criticisms reside, not in the PISA methods and characteristics themselves but on
an excessive focus on country rankings, primarily promoted by media, and consequently followed by
political leaders.
The main objective of this research is to reframe difficulties and artefacts together with virtuous results of PISA, putting in perspective praises and criticisms to foster a better understanding of this important programme.info:eu-repo/semantics/publishedVersio
What PISA intends to achieve and can achieve : a critical programme theory analysis
No full textIn 2000, when the first Programme for International Student Assessment (PISA) test of 15-year-olds reading skills was launched by the Organisation for Economic Cooperation and Development (OECD), it marks the start of an OECD led discourse on the quality of national education systems. Test scores of students’ knowledge, ability to reflect and apply their knowledge and experience to real-world issues were used to measure the quality of education systems (OECD, 2001). OECD/PISA is more than an international student test and should be described and analyzed as a programme for transnational governance of education systems (OECD, 2009; Grek, 2010, 2012; Lundgren, 2011; Popkewitz, 2011). PISA produces student performance data every third year together with policy reports for actors in the school sector (Carvalho, 2012; Mangez and Hilgers, 2012). PISA has become a global phenomenon permeating national education discourses world-wide and has influenced policy reforms in participating countries, according to members of PISA Governing Board (Breakspear, 2012). If those in power make the same judgment is not explored, but the paper will critically look into the assumptions regarding how PISA will attain its intended effects, and how consistent these assumptions are. If PISA’s programme theory (PT) is consistent, PISA is more likely to achieve intended effects.The purpose of this article is to unfold and describe PISA’s PT, that is, what PISA intends to achieve and how, and to critically probe these assumptions, and to discuss how PISA’s PT can be used for further research. A special attention is paid to if the PT has support in research on educational governance, accountability and school development.PISA has recently been assessed in a special issue of the European Educational Research Journal. The issue focused on how PISA is ‘fabricated’, that is, constructed and reconstructed in and across different contexts, involving many actors and different kinds of knowledge (Ozga, 2012, 166). Although PISA is partly developed at the OECD level and partly at the national level, the “fabrication of PISA” in different member states, should be kept apart from OECD’s policy making. What this special issue, and other analysis of PISA, has not made quite clear is how the various activities and assumptions of PISA are linked together at the transnational programme level and if these assumptions are consistent. PISA can be analysed as a transnational programme implemented in member states, and/or as a transnational programme being fabricated while implemented in member states. This paper elaborates an analysis of PISA as a transnational programme which we argue needs an analysis in its own right.The article integrates knowledge from three broad research fields: governance research; (education) policy research; and research on evaluation systems. The framework reflects OECD’s steering of PISA and the interplay between (transnational) governance and PISA. Conceived through this framework OECD develops PISA to meet OECD’s knowledge needs and OECD filters PISA results through policy reports and synthesis reports, and integrates knowledge from various evaluation studies to achieve its intentions.Methodology, Methods, Research Instruments or Sources UsedThe critical PT-analysis includes three steps and searches answers to the following questions: Step 1:Reconstruction of PISA’s PT: 1. What are the assumptions of PISA? 2. What is the problem PISA is aimed to resolve? 3. What are the pre-requisites for PISA, and which activities are assumed to produce which effects? 4. Are the problems that PISA intends to manage described and substantiated? 5.Are intended effects clearly described/ specified? Step 2:Assessment of the PT’s internal validity 6. Is PISA’s PT consistent? (e.g. is there a logical and coherent description of how programme activities shall achieve intended effects?) Step 3:Assessment of PT’s external validity 7.Does PISA have scientific support? 8.Is the knowledge that PISA produces relevant to help resolving the problem that PISA was set up to manage? 9.What value does the knowledge produced have for governance, accountability and school development? The PT-analysis is based on document analysis and interviews with well-informed persons at the OECD and country level (Sweden). Conclusions, Expected Outcomes or FindingsThe expected result of this analysis is a contribution to existing knowledge of PISA, mainly of the nature of PISA’s PT. The paper generates knowledge of how assumptions are linked together and of the consistency of PISA’s PT. This knowledge provides further insight into PISA including which objectives and intended effects PISA has a potential to achieve. PISA’s PT provides a construct that can be inter-subjectively shared which has a value in its own right; advocates and critics of PISA can deliberate about PISA’s nature, assumptions and the programme’s potential. The PT analysis focuses on intended effects, of importance when exploring intended and unintended effects and consequences of PISA in the context of educational governance. PISA’s PT can also be used for further research of use of PISA for accountability and school development in different countries and at different levels of government.</p
Quality monitoring of urban green areas of Pisa
No full textThe European Union, in the “Thematic Strategy on the Urban Environment” (2006),
has pointed out the importance of identification and monitoring urban environment
quality indicators. In this scheme, the quality of 31 urban green areas in Pisa was assessed
by monitoring topsoil physical, chemical and biological features and by using the plant
bioindicator Taraxacum officinale Web. Results were compared with an extra-urban area
(near S.Rossore-Migliarino-Massaciuccoli Natural Park) and with the quantitative limits
fixed by Italian Law (DLgs 152/2006). The soils of the green areas of Pisa were mostly
sandy, sub-alkaline, and lightly calcareous, with rather high organic matter content. They
showed a widespread pollution by hydrocarbons, probably caused by road traffic
incomplete combustion and by domestic heating. Only in few sites the total amounts of
Cd, Cr and Hg were significantly higher than the minimum value established by the
Italian Law. Probably due to the vehicular traffic, pollution by Pb, Cu and Zn was instead
widespread. A sequential extraction (BCR method) was performed for determining the
forms of heavy metals within the soil matrix. Instead of Zn and Pb, Cr and Cu showed the
absence in soil of the labile forms. As far as Cr forms were concerned, the most
represented one was the residual, while the anthropogenic addition of the element was
found in the oxidizable form. For Cu forms, the most represented was the residual, while
reducible and oxidizable forms were enriched by anthropogenic addition of the element.
Regarding Pb and Zn forms, the most represented one was the reducible, while the
anthropogenic additions of the elements were evenly distributed among the four fractions.
Principal component analysis revealed the existence of four different patterns of
distribution of the elements, whose differences have been attributed at the origin, each
composed of a different number of variables: the first one, consisting of As, Cd, Cr, Cu, Pb,
Sb, Sn, Sr, and Zn, whose main source was fit to identify in the traffic; as to the second
factor, consisting of Fe, Mn, and Ni, the main source was identified by pedogenic
substrate. Each of the third and the fourth factor was composed of a single element,
respectively Cr and Hg, which had a particular distribution, different from that of all other
HMs. Even the geostatistical analysis has identified the previous four patterns of
distribution of HMs, bringing back, through interpolation techniques, also their coarse
spatial distribution; according to this analysis, the central area of the city was identified as
the one having the most polluted green areas. Hierarchical clustering analysis identified
different groups of areas with different levels of contamination, both from the qualitative
and quantitative point of view. Platinoids (Pt, Pd), “new generation” pollutants, released
from recently introduced three way catalytic converters, absent in the substrate, showed a
beginning of accumulation in a limited number of areas. As to soil biological features,
cumulative respiration of monitored areas was evaluated during a 25 day incubation
period. Results showed that evolved CO2-C was different among the monitored areas and
influenced by soil carbon total content and pollution level. Community level physiological
profiling of soil microbial population of the monitored areas was performed by using Biolog Ecoplates. The relative data of AWCD, CMD and H (Shannon-Weaver index of
biodiversity) showed a limited variability among the monitored areas. Soil antioxidant
capacity was evaluated and showed changes among monitored areas, being correlated
with organic carbon content and, in particular, with phenolic substances. Soil enzymatic
activities vary among monitored sites and appear to be influenced by organic matter and
pollutants’ contents. The control site has shown the lowest rate of activities if compared to
all the other sites. Positive correlation was detected among all enzymatic activities except
for dehydrogenase. In spite of the presence of various pollutants, vegetal bioindicator
Taraxacum officinale Web. did not show any alteration in the photosynthetic process with
values of Fv/Fm, and FPSII, representing respectively the efficiency of PSII in conducting
photochemical events and photochemical yield of PSII, typical of the leaves of healthy
plants. Even photosynthetic pigment contents and qNP, representing mechanisms aiming
at dissipating excess excitation energy, did not show any alteration among the monitored
areas. That trend was confirmed by other parameters, monitored in order to understand if
the polluted urban environment is not dangerous for the plant or if vegetal put into
repairing actions. On the dissected aboveground and radical portions of the biomarker,
antioxidant capacity, phenolic content, heavy metals contents and metal chelating capacity
of vegetal tissues did not reveal any differences among the monitored sites, probably
showing the dandelion ability in non-absorbing pollutants. We can finally conclude that
the degree of pollution of the green areas in the city of Pisa, although present, does not
cause major problems to the utilized bioindicators. We need more sensible biomarkers to
effectively detect this degree of pollution
A combined experimental and computational study for a quantitative characterization of Pt --> C back-donation in Pt(II)-carbene complexes
No full textThe aim of this work was to characterize the Pt - C chemical bond by a combined experimental and computational study. On this purpose, new carbenes complexes have been synthetized and VT-EXSY experiments were performed to obtain rotational thermodynamic parameters, which were hypothesized to be proportional to the Pt --> C back-donation. On the other side, DFT calculations were carried out to obtain a quantitative picture of donation and back-donation components of Pt - C bond. Consequently, the relationship between computed and spectroscopic measurements were discussed
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