La tradici?n oral como estrategia pedag?gica para el fortalecimiento de la etnoeducaci?n afrocolombiana inicial, en ni?os y ni?as de 3 a 5 a?os en el Centro de desarrollo infantil CDI El Guadual, municipio de Villa Rica, Cauca Fundaci?n "Casita de ni?os"

La tradici?n oral como estrategia pedag?gica para el fortalecimiento de la etnoeducaci?n afrocolombiana inicial, en ni?os y ni?as de 3 a 5 a?os en el Centro de desarrollo infantil CDI El Guadual municipio de Villa Rica, Cauca, es un proyecto de investigaci?n que busca aportar al fortalecimiento de las diversas identidades es culturales afrodescendientes, en ni?os y ni?as en educaci?n inicial, a trav?s de una pr?ctica pedag?gica que recupera y da valor a la oralidad, como parte de la herencia ancestral de la di?spora africana. Para el desarrollo del presente trabajo de grado, se parte de la pregunta: ? C?mo las pr?cticas ancestrales aportan al fortalecimiento de la Etnoeducaci?n Afrocolombiana inicial de ni?os y ni?as afrocolombianas de primera infancia en el CDI el Guadual, municipio de Villa Rica, Cauca? Cuyas respuestas se rastrean a partir de los aportes te?ricos de autores como el Dr. Carlos Velazco D?az, qui?n a trav?s de su trayectoria profesional ha rescatado diversas manifestaciones culturales de la regi?n, Heliana Portes de Roux, entre otros y las versiones que van de boca, en o?do narradas por las abuelas afrodescendientes, quienes son s?mbolo de autoridad y afecto.

Synthesis, characterization and chemical vapor deposition of transition metal di(tert-butyl)amido compounds

Although the transition metal chemistry of many dialkylamido ligands has been well studied, the chemistry of the bulky di(tert-butyl)amido ligand has been largely overlooked. The di(tert-butyl)amido ligand is well suited for synthesizing transition metal compounds with low coordination numbers; such compounds may exhibit interesting structural, physical, and chemical properties. Di(tert-butyl)amido complexes of transition metals are expected to exhibit high volatilities and low decomposition temperatures, thus making them well suited for the chemical vapor deposition of metals and metal nitrides. Treatment of MnBr₂(THF)₂, FeI₂, CoBr₂(DME), or NiBr₂(DME) with two equivalents of LiN(t-Bu)2 in benzene affords the two-coordinate complex M[N(t-Bu)₂]₂, where M is Mn, Fe, Co, or Ni. Crystallographic studies show that the M-N distances decrease across the series: 1.9365 (Mn), 1.8790 (Fe), 1.845 (Co), 1.798 Å (Ni). The N-M- N angles are very close to linear for Mn and Fe (179.30 and 179.45°, respectively), but bent for Co and Ni (159.2 and 160.90°, respectively). As expected, the d⁵ Mn complex has a magnetic moment of 5.53 μΒ that is very close to the spin only value. The EPR spectrum is nearly axial with a low E/D ratio of 0.014. The d⁶ Fe compound has a room temperature magnetic moment of 5.55 μΒ indicative of a large orbital angular momentum contribution. It does not exhibit a Jahn-Teller distortion despite the expected doubly degenerate ground state. Applied field Mössbauer spectroscopy shows that the effective internal hyperfine field is unusually large, Hint = 105 T. The magnetic moments of Co[N(t-Bu)₂]₂ and Ni[N(t-Bu)₂]₂ are 5.24 and 3.02 μΒ respectively. Both are EPR silent at 4.2 K. Treatment of TiCl₄ with three equivalents of LiN(t-Bu)2 in pentane affords the briding imido compound Ti₂[μ-N(t-Bu)]₂Cl₂[N(t-Bu)₂]₂ via a dealkylation reaction. Rotation around the bis(tert-butyl)amido groups is hindered, with activation parameters of ΔH‡ = 12.8 ± 0.6 kcal mol-1 and ΔS‡ = -8 ± 2 cal K-1 ·mol-1, as evidenced by variable temperature 1H NMR spectroscopy. Treatment of TiCl₄ with two equivalents of HN(t-Bu)₂ affords Ti₂Cl₆[N(t-Bu)₂]₂. This complex shows a close-contact of 2.634(3) Å between Ti and the carbon atom of one of the CH₃ substituents on the tert-butyl groups. Theoretical considerations and detailed structural comparisons suggest this interaction is not agostic in nature, but rather is a consequence of interligand repulsions. Treatment of NiI₂(PPh3)₂ and PdCl₂(PPh₃)₂ with LiN(t-Bu)₂in benzene affords Ni[N(t-Bu)₂](PPh₃)I and Pd₃(μ₂-NBut₂)2(μ₂-PPh₂)Ph(PPh₃) respectively. The compound Ni[N(t-Bu)₂](PPh₃)I has distorted T-shape in geometry, whereas Pd₃(μ₂-NBut₂)₂(μ₂-PPh₂)Ph(PPh₃) contains a triangular palladium core. Manganese nitride films were grown from Mn[N(t-Bu)₂]₂ in the presence of anhydrous ammonia. The growth rate was several nanometers per minute even at the remarkably low temperature of 80⁰C. As grown, the films are carbon- and oxygen-free, and have a columnar morphology. The spacings between the columns become smaller and the films become smoother as the growth temperature is increased. The composition of the films is consistent with a stoichiometry of Mn₅N₂.

Scavo 2015 della necropoli romana di Porta Nocera a Pompei: nascita e sviluppo di un paesaggio funerario romano (I sec. a.C. - I sec. d.C.)

The Porta Nocera 2 program aims to study the process of establishing and developing a Roman urban necropolis from a road network, which is an essential setting in the expression of death in the Roman time. As such, the necropolis of Porta Nocera essentially excavated between 1952 and 1958 and then in 1983 offers a privileged field study. Indeed, monuments and funerary enclosures with burial structures (graves, cremation areas) built along the road to Nocera are well preserved and allow to observe funerary practices on a relatively short time, about 160 years, since we can assume that the necropolis has been founded with the colony in 80 BC. It is then the necessity to organize a burial area according to Roman customs, which is at the origin a new landscape development until then essentially marked by the presence of the urban wall.

La lunga diacronia di un sito archeologico toscano: il complesso di Pava (Siena) dal II al XIII sec. d.C.

The paper is centred on southern Tuscany on the archaeological complex of Pieve di Pava where archaeological research have been conducted since the 2000 by the University of Siena. The parish church is first mentioned as the baptisterium Sancti Petri in Pava in a document of AD 715 part of a long dispute between the bishop of Siena and the bishop of Arezzo. But the archaeological excavation revealed a longer history of the site that start from the Roman period with a villa dated between the second to the fourth century BC. The villa continued to grow in Late Antiquity since it was transformed by a church. The paper is centred on these fluctuations of the site and on the implications of the transformations on the landscape. One of the stronger element of the Pava site, in addition to the very particular plan of the early church (built with two opposing apses) was the huge cemetery around the church that was used from the seventh century BC until the Middle Ages. The 900 excavated graves make this one of the largest and most long-lasting late-Roman to medieval cemeteries excavated in Europe.

Delle Benemerenze di S. Tommaso d'Aquino verso le Arti Belle.

Mode of access: Internet.

Gli antichi cimiteri cristiani di Roma e d'Italia.

Mode of access: Internet.

Discorso dellʹeminentissimo e reverendissimo signor Cardinale Carlos di Reisach alle Pontificie accademie romane di S. Luca e di archeologia insieme adunate il dì XVII di Marzo MDCCCLIX.

Mode of access: Internet.

Studio di fattibilità della ricostruzione del decadimento $D^0\to K^-\mu^+\nu_{\mu}$ ad LHCb

Il Modello Standard delle particelle elementari prevede l’universalità del sapore leptonico, cioè l’uguaglianza della probabilità di accoppiamento dei bosoni di gauge carichi dell’interazione debole con tutti i leptoni. Recentemente, le Collaborazioni LHCb, BaBar e Belle, misurando il rapporto tra i branching ratio dei decadimenti $B^0\to D^{∗− }\tau^+\nu_{\tau} e $B^0 →D^{∗−}\mu^+\nu_{\mu}, hanno osservato una deviazione dai valori previsti dal Modello Standard di 3.9 deviazioni standard. Questo interessante risultato, se confermato, indicherebbe l’esistenza di nuove particelle, come per esempio il bosone di Higgs carico. Analogamente ai decadimenti del mesone $B^0$ , è possibile cercare effetti analoghi anche nel rapporto di branching ratio dei decadimenti $D^0\to K^ −\mu^+\nu_{\mu}$ e $D^0\to K^−e^+\nu_e$ . In questo lavoro di tesi è stato realizzato uno studio preliminare di questa misura. In particolare, è stato studiata, tramite simulazioni Monte Carlo, la ricostruzione del processo $D^{*\pm}\to D^0 (\to K^− \mu+\nu_{\mu})\pi_s^{\pm}$ nell’esperimento LHCb. Questo canale ha la particolarità di avere una particella invisibile, il neutrino, al rivelatore LHCb. Tuttavia, mediante vincoli cinematici e topologici, è possibile ricavare le componenti dell’impulso del neutrino, con risoluzioni non paragonabili a quelle di una particella visibile, ma comunque accettabili. In questa tesi sono riportati i calcoli che permettono di ottenere queste informazioni ed è stata studiata la risoluzione sulla massa invariante del $D^{∗\pm}$ . La tesi è organizzata nel seguente modo: il primo capitolo riporta le motivazioni della misura dei rapporti dei branching ratio e l’attuale stato sperimentale; il secondo capitolo contiene una breve descrizione del rivelatore LHCb; il terzo capitolo, infine, descrive lo studio di fattibilità della ricostruzione del decadimento $D^0\to K^-\mu^+\nu_{\mu}.