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Scopo del lavoro è presentare un repository (Italian Recording for the Appropriate Management of Odontoiatric Patient, IRAMOP) per la registrazione delle prestazioni odontoiatriche effettuate sui pazienti afferenti a cinque sedi universitarie italiane relativamente alle specialità ortodontiche, chirurgiche, implantologiche, parodontali ed endodontiche.

Biocompatibility of root canal filling materials is of great interest because they can come into permanent contact with the living periapical tissue, and induce mild or severe inflammatory responses. Usually biocompatibility tests only determine non-cytotoxic effects of dental materials, even if their functional interactions with cells also play a role in the host responses. The purpose of this study is to evaluate peripheral blood monocyte (PBM) vitality and functionality after contact with 5 different root canal filling materials: Thermafil (gutta-percha), Real Seal and Real Seal 1 (methacrylic resins), AureoSeal (MTA) and SuperSeal (EBA). Cellular vitality was determined by MTT test and cellular functionality by Chemiluminescence (CL) technique. Dishes of the materials were covered with cell culture medium (0.5 cm2/mL) and incubated for 24 h. The extracts were added to PBMs and the latter, after 2 h of incubation, were analysed by MTT and by Chemiluminescence (CL). All results are expressed as mean ± SEM. The group means were compared by analysis of variance. Results showed that SuperSeal and AuroSeal exhibited a moderate cytotoxic effect, while the toxicity induced by RealSeal, RealSeal 1 and Thermafil was lower. SuperSeal and AuroSeal induced a significant decrease of both oxidative burst and basal reactive oxygen species (ROS) production. RealSeal 1 caused a doubling of basal ROS production in respect to control. The results demonstrate that a low cytotoxic effect does not guarantee a total integrity of cellular functionality and more differences among biocompatibility of root canal materials can be detected when a functionality test is used.

Oral focal mucinosis (OFM) is a rare mucosal lesion of unknown etiopathogenesis. It is considered the oral counterpart of cutaneous focal mucinosis. From the anatomo-pathological point of view it is characterised by a focal degeneration of myxoid type of connective tissue. A literature survey revealed 50 reports of OFM cases worldwide. Here, we present an even more rare case with tongue involvement. Particular emphasis is placed on diagnostic-differential aspects of this kind of lesion, both from the clinical and the histopathological point of view, in respect to other manifestations of tongue mucosa.

Apical extrusion of infected debris to the periradicular tissues is considered one of the possible factors related to the occurrence of postoperative pain and inflammation. The goal of the present study is to evaluate and compare the incidence and intensity of postoperative pain using two different nickel-titanium instrumentation techniques: a rotary crown-down technique using TF instruments (SybronEndo, Orange, Ca, USA) and a reciprocating single-file technique using Reciproc instruments (VDW, Munich, Germany). Sixty patients requiring endodontic treatment on permanent premolar and molar teeth with non-vital pulps preoperatively were included in the study. The patients were divided into two groups of 30 patients each, trying to make the groups very similar, concerning the number of root canals, presence of initial pain and periapical lesions. The teeth in group 1 (n = 30) were treated with a crown-down technique using TF instruments whilst those in group 2 (n = 30) were treated with, a single-file technique using Reciproc 08 25. All canals were shaped, cleaned and obturated in a single-visit. The assessment of postoperative pain was carried out at 3 days by using a visual analogue scale. CAi-square tests and independent-sample t-tests to compare the incidence and intensity of postoperative pain of two groups were carried out. A statistically significant difference was found between the two techniques. When comparing patients who developed no pain, the TF instrumentation technique showed significantly better results (chi-square = 4.059 P= 0.039). When evaluating patients experiencing severe pain the incidence of symptoms was significantly higher with the Reciproc technique (chi-square = 7.246 P= 0.023). Since the incidence of preoperative pain, the type of tooth and the pulp and periodontal pathology were quite similar between the two tested groups, and all the other variables (operator, irrigation, and obturation) were identical, the difference in postoperative pain can be mainly related to the different instrumentation technique

Abstract: The transient and steady effects of positronium yield in polyethylene, due to the application and removal of an external electric field, have been studied. The time-dependent electric field effective in the Ps formation region was deduced from yield measurements.

Abstract: The feasibility of ruthenium metabolism studies by stable tracer administration, with a methodology based on proton nuclear activation, is presented. In order to test that the amount of stable tracer administered does not perturb significantly the mechanism investigated, a series of comparative experiments with administration of both radioactive and stable tracers has been performed on animals. As the most critical pathway seems to be the intravenous injection, four male rabbits were given an intravenous injection of radioactive106Ru. Successively, the rabbits were given either a further injection of radioactive106Ru or injection of different quantities of natural Ru. The activity of106Ru and the concentration of natural Ru were measured in plasma samples withdrawn at different time intervals from the injections and the results were compared. Some biokinetic parameters and tissue distribution of Ru in rabbits were determined.

Abstract: An investigation on tellurium metabolism by administration of stable tellurium isotopes124Te and126Te has been performed. Fractional intestinal absorption was determined in rabbits by the double tracer technique. The investigated subjects were given an enriched solution of one tellurium isotope orally and a few minutes later an enriched solution of the other isotope intravenously. The124Te and126Te contents in plasma samples were determined by proton nuclear activation. The methodology described offers a means to study tellurium metabolism in humans without radiation risk.

Abstract: A method for Cr determination in biological samples based on proton nuclear activation is presented. The activation was induced by a 13.8 MeV proton beam of the AVF Cyclotron of Milan University via a (p, n) reaction on the nuclei of the target. For the quantitative determination Cd has been chosen as reference element. The method has been applied to Cr determination in human serum samples. The experimental procedure is described and results are presented and discussed.

The time spectrum of positrons annihilated in benzene, in nitrobenzene and in their solutions was analysed. The main results attained through the measurements of the intensity and of the decay rate of the various components, as a function of the concentration, as well as through a magnetic-quenching experiment are the following: i) orthopositronium in benzene is localized in two regions differently exposed to the action of quenching and inhibiting agents, ii) the nitrobenzene molecule captures a positron giving rise to a bound system whose lifetime in nitrobenzene is τ = (0.395 ± 0.005) ns. Si è studiato lo spettro temporale delie annichilazioni dei positroni in benzene, in nitrobenzene e nella loro soluzione. I principali risultati che sono stati raggiunti sia misurando le intensità e le costanti di decadimento delle varie componenti spettrali in funzione della concentrazione, sia mediante un esperimento di spegnimento magnetico sono i seguenti: 1) nel benzene l’ortopositronio è localizzato in due regioni differentemente esposte all’azione degli agenti inibitori e spegnenti, 2) la molecola di nitrobenzene cattura il positrone dando luogo alla formazione di un sistema legato la oui vita media è Τ= (0.395 ± 0.005) ns. АНАлИжИРУЕтсь ВРЕМЕ ННОИ спЕктР пОжИтРОН ОВ, АННИгИлИРУУЩИх В БЕНжОлЕ, В НИтРОБЕНж ОлЕ И В Их РАстВОРАх. Ос НОВНыЕ РЕжУльтАты, пОлУЧЕНН ыЕ с пОМОЩьУ ИжМЕРЕНИИ И НтЕНсИВНОстИ И скОРО стИ РАспАДА РАжлИЧНых кОМпОНЕНт, кАк ФУНкцИИ кОНцЕНтР АцИИ, А тАкжЕ Иж ЁкспЕР ИМЕНтА пО МАгНИтНОИ жАкАлкЕ, пР ЕДстАВльУт: 1) ОРтОпОжИ тРОНИИ В БЕНжОлЕ лОкА лИжОВАН В ДВУх ОБлАст ьх, кОтОРыЕ РАжлИЧ БЕНжОлЕ лОкАлИжОВАН В ДВУх ОБлАстьх, кОтОР ыЕ РАжлИЧНО РЕАгИРУУ т НА ДЕИстВИЕ ФАктОРО В жАкАлкИ И жАМЕДлЕНИ ь; 2) МОлЕкУлА НИтРОБЕНж ОлА жАхВАтыВАЕт пОжИ тРОН, ЧтО РЕАгИРУУт НА ДЕИстВИ Е ФАктОРОВ жАкАлкИ И ж АМЕДлЕНИь; 2) МОлЕкУлА Н ИтРОБЕНжОлА жАхВАты ВАЕт пОжИтРОН, ЧтО пРИ ВОДИт к ОБРАжОВАНИУ с ВьжАННОИ МОлЕкУлА НИтРОБЕНжО лА жАхВАтыВАЕт пОжИт РОН, ЧтО пРИВОДИт к ОБР АжОВАНИУ сВьжАННОИ пРИВОДИт к ОБРАжОВАН ИУ сВьжАННОИ сИстЕМы, ВРЕМь жИжНИ к ОтОРОИ В НИтРОБЕНжОл Е сОстАВльЕт т=(0.395 ±0.005) Нс.

Abstract: An apparatus for cyclic charged particle activation was designed, built and connected to the 7 MV Van de Graaff CN accelerator of the Laboratori Nazionali dell'Istituto Nazionale di Fisica Nucleare di Legnaro (Italy). It mainly consists of a two-sample transverse moving system controlled by a Cycle Control Module (CCM). This module is based on a Programmable Logic Device (PLD) for the definition of the requested flow-maps and functions. The CCM operates the cc motor for sample movements by means of a power width modulation technique. It also controls the beam switch and the setting mode of the acquisition system which is connected to two HPGe detectors. As a feasibility test, the best experimental conditions for aluminium determination in complex. Al-doped biological samples were found to be an irradiation time of 3.5 minutes and a measuring time of 6 minutes. The signal to background ratio is reported as a function of the number of cycles.

The disappearance rates of positrons annihilated in some inorganic compounds were measured. The observed correlation between these rates is discussed on the basis of a two-state trapping model. Sono state misurate le costanti di decadimento di positroni che annichilano in alcuni composti inorganici. Si pone in evidenza una correlazione tra queste costanti e la si discute sulla base di un modello a transizione tra due stati aventi differente densità elettronica. Измеряются постоянные распада позитронов, которые аннигилируют в некоторых неорганических соединениях. Обсуждается наблюденная корреляция между интенсивностями аннигиляции на основе модели перехода между двумя состояниями, имеющими различные электронные плотности.

Implantation in mylar of positrons from22Na was investigated in «broad beam» arrangement. The absorption curve was resolved into two components pertaining to the primary and the scattered beam, respectively. Here the shape of the curve is given in terms of the mylar mass absorption coefficient and of the atomic number of the scatterer. The role played by the scattered positrons in populating the surface layers is outlined.

Without Abstract:

The positronium formation was investigated as a function of a static electric field in various polymers. With increasing field strength the Ps relative yield at first declines, passes through a minimum which can be very flat, then rises rapidly, exceeds unity and approaches the saturation value. The experimental results can be well framed by a compound model which assumes that Ps formation occurs partly in the Ore gap and partly in the positron spur. This model enabled us to obtain mean values of the rates for positron elastic scattering and energy loss and for Ps formation above the threshold energy. The relative contribution of the two processes to Ps formation at zero field is also obtained together with the mean distance between positron and electron in the spur.

The role played by the O2molecule in the decay of Ps in air-saturated hexane was investigated by measurements of lifetime and by an experiment of magnetic quenching. The results indicate that a) O2reduces the overlap probability |φ(O)|2of the interacting positron-electron pair in Ps by a factor 1.6, b) Ps may react with the O2molecule forming a short-lived compound with a rate constant kq=5.7·10−11cm3s−1and c) it may undergo exchange collisions with unpaired electrons of the O2molecule with a rate constant γq= cm3s−1.

Two volunteer subjects were given orally enriched solutions of Mo-95 and Mo-96 respectively. Blood samples were drawn at various times following the tracer administration.

The decay rate of ortho-positronium was measured in degassed molecular liquids. It was found that each atom contributes to the pick-off quenching with an effective number of electrons in the singlet state which does not appear to be perceptibly affected by the structural properties of the molecules. This result is discussed in the framework of the free-volume model proposed by Brandt and co-workers. È stata misurata la probabilità di decadimento dell’ortopositronio in liquidi molecolari degasati. Si è trovato che ciascun atomo contribuisce alla probabilità di annichilazione per « pick-off » con un numero di elettroni efficaci, in stato di singoletto, indipendente dalle proprietà strutturali delle molecole. Questo risultato viene discusso nell’ambito del modello a volume libero proposto da Brandt e collaboratori. Иэмерялась скорость распада орто-поэитрония в дегаэированных молекулярных жидкостях. Было обнаружено, что каждый атом участвует в подавлении чувствительного злемента с зффективным числом злектронов в синглетном состоянии, которое, окаэывается, сушественно не подвергается воэдействию структурных свойств молекул. Этот реэультат обсуждается в рамках модели свободного общема, предложенной Брандтом и сотрудниками.

The collisions of the positronium atom with unpaired electrons were studied in aqueous solutions of NiCl2through measurement of lifetime and through an experiment of magnetic quenching. These collisions, by causing transitions between all the Ps states, determined a) a shortening of ortho-Ps lifetime at zero field, 6) a marked reduction of the quenching ratio at high field (H > 10 000 G). The results of our measurements are interpreted by means of the Halpern theory of magnetic quenching and by means of the description of exchange collisions given by Ferrell. The ortho-para conversion rate (at Ni++ion concentration of 6.1019cm-3) is found to be γ = (0.29 ±0.01) ns-1. The overlap probability |yg(0)|2of the interacting positron-electron pair in Ps was obtained from a further experiment of magnetic quenching in pure water. Si riportano i risultati sperimentali di una ricerca sulle collisioni dell’atomo di positronio con ioni paramagnetici, effettuata mediante misure di vita media e mediante un esperimento di spegnimento magnetico. Tali urti determinano transizioni tra tutti gli stati del positronio, dando luogo a 1) una diminuzione della vita media dell’ortopositronio a campo nullo, 2) un forte abbassamento del rapporto di spegnimento ad alti eampi (H > 10000 G). I risultati ottenuti sono interpretati utilizzando sia la teoria di Halpern sullo spegnimento magnetico, sia la descrizione degli urti di scambio data da Ferrell. La costante di conversione orto-para in soluzione aequosa 0.1 M di NiCl2ottenuta è γ = (0.29 ±0.01) ns-1. La densità elettronica, nell’origine, del sistema legato elettrone-positrone è stata ricavata da un ulteriore esperimento di spegnimento magnetico in acqua pura. Исследуются соударения атома позитрония с неспаренными электронами в водных растворах NiCl2, используя измерения времени жизни и эксперимент по м используя измерения времени жизни и эксперимент по магнитной закалке. Эти соударения, вызывающие переходы между всеми состояниями позитрония, определяют магнитной закалке. Эти соударения, вызывающие переходы между всеми состояниями позитрония, определяют: а) сокращение времени жизни орто-позитрония при нулевом поле; б) заметное уменьшение отношеиня за переходы между всеми состояниями позитрония, определяют: а) сокращение времени жизни орто-позитрония при нулевом поле; б) заметное уменьшение отношеиня закалки при высоком поле (H > 10000 G). Результаты наших измерений интерпретируются с помощью теории определяют: а) сокращение времени жизни орто-позитрония при нулевом поле; б) заметное уменьшение отношеиня закалки при высоком поле (H > 10000 G). Результаты наших измерений интерпретируются с помощью теории магнитной закалки Халперна и с помощью описания обменных соударений, предложенного Ф орто-позитрония при нулевом поле; б) заметное уменьшение отношеиня закалки при высоком поле (H > 10000 G). Результаты наших измерений интерпретируются с помощью теории магнитной заклки Халперна и с помощью описания обменных соударений, предложенного Ферреллом. Получено, что интенсивность орто-пара конверсии (при концентрации ионов Ni+уменьшение отношеиня закалки при высоком поле (H > 10000 G). Результаты наших измерений кнтерпретируются с помощью теории магнитной закалки Халперна и с помощью описания обменных соударений, предложенного Ферреллом. Получено, что интенсивность орто-пара конверсии (при концентрации ионов Ni+6.1019см-3) составляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимодействующей позитрон-эл Результаты наших измерений интерпретируются с помощью теории магнитной закалки Халперна и с помощью аписания обменных соударений, предложенного Ферреллом. Получено, что интенсивность орто-пара конверсии (при концентрации ионов Ni+6.1019см-3) составляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимодействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. помощью теории магнитной какалки Халперна и с помощью описания обменных соударений, предложенного Ферреллом. Получено, что интенсивность орто-ара конверсии (при кнцентрации ионов Ni+6.1019см-3) составляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимодействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. описания обменных соударений, предложенного Ферреллом. Получено, что интенсивность орто-пара конверсии (при концентрации ионов Ni+6.1019см-3) составляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимодействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. Ферреллом. Плучено, что интенсивность орто-пара конверсии (при концентрации ионов Ni+6.1019см-3) составляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимодействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. конверсии (при концентрации ионов Ni+6.1019см-3) су ставляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимоействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. составляет γ = (10.29 ±0.01) нс-1. Вероятность перекрытия ¦у>(0)¦2взаимодействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. ¦у>(0)¦2взаимодействующей позитрон-электронно й пары в Ps получается из дополнительного эксперимента по магнитной закалке в чистой воде. в Ps получается из дополнителього эксперимента по магнитной закалке в чистой воде. магнитной закалке в чистой воде.

Abstract: The intensity of the τ2-component of positrons annihilated in polyethylene is found to increase with increasing electric field, while the formation probability of the positron state responsible for this component remains independent of the field.

A magnetic-quenching experiment on positronium in mylar has re-vealed an anomalously large effect at low fields.

A method has been developed, based on thermoluminescent dosemeters (TLD), aimed at measuring the absorbed dose in tissue-equivalent phantoms exposed to thermal or epithermal neutrons, separating the contributions of various secondary radiation generated by neutrons. The proposed method takes advantage of the very low sensitivity of CaF2:Tm (TLD-300) to low energy neutrons and to the different responses to thermal neutrons of LiF:Mg,Ti dosemeters with different 6Li percentage (TLD-100, TLD-700, TLD-600). The comparison of the results with those obtained by means of gel dosemeters and activation foils has confirmed the reliability of the method. The experimental modalities allowing reliable results have been studied. The glow curves of TLD-300 after gamma or neutron irradiation have been compared; moreover, both internal irradiation effect and energy dependence have been investigated. For TLD-600, TLD-100 and TLD-700, the suitable fluence limits have been determined in order to avoid radiation damage and loss of linearity.

A method was investigated to measure gamma and fast neutron doses in phantoms exposed to an epithermal neutron beam designed for neutron capture therapy (NCT). The gamma dose component was measured by TLD-300 [CaF2:Tm] and the fast neutron dose, mainly due to elastic scattering with hydrogen nuclei, was measured by alanine dosemeters [CH3CH(NH2)COOH]. The gamma and fast neutron doses deposited in alanine dosemeters are very near to those released in tissue, because of the alanine tissue equivalence. Couples of TLD-300 and alanine dosemeters were irradiated in phantoms positioned in the epithermal column of the Tapiro reactor (ENEA-Casaccia RC). The dosemeter response depends on the linear energy transfer (LET) of radiation, hence the precision and reliability of the fast neutron dose values obtained with the proposed method have been investigated. Results showed that the combination of alanine and TLD detectors is a promising method to separate gamma dose and fast neutron dose in NCT.

Dosimetry and spectrometry measurements have been carried out in the thermal column of the research fast reactor RSV-TAPIRO (ENEA-Casaccia, Rome) in order to investigate its suitability for irradiation of cells or mice, with a view to research in the interests of boron neutron capture therapy (BNCT). The thermal column consists of a graphite moderator (40 cm thick) containing a lead shield (13 cm thick) in order to shield reactor background. The irradiation volume, inside this structure, has cubic shape (18 × 18 × 18 cm3). Besides measurements of fluence and dose rates in air or in phantom performed with thermoluminescence dosemeters (TLDs) and using the activation technique, dose and fluence profiles have been generated using a method based on gel dosemeters analysed with optical imaging. To check the consistency of the results, spectrometry measurements in the same irradiation volume have been performed by means of bubble detectors.

A collimated epithermal beam for boron neutron capture therapy (BNCT) research has been designed and built at the TAPIRO fast research reactor. A complete experimental characterisation of the radiation field in the irradiation chamber has been performed, to verify agreement with IAEA requirements. Slow neutron fluxes have been measured by means of an activation technique and with thermoluminescent detectors (TLDs). The fast neutron dose has been determined with gel dosemeters, while the fast neutron spectrum has been acquired by means of a neutron spectrometer based on superheated drop detectors. The gamma-dose has been measured with gel dosemeters and TLDs. For an independent verification of the experimental results, fluxes, doses and neutron spectra have been calculated with Monte Carlo simulations using the codes MCNP4B and MCNPX_2.1.5 with the direct statistical approach (DSA). The results obtained confirm that the epithermal beams achievable at TAPIRO are of suitable quality for BNCT purposes.

Gel dosimetry allows three-dimensional (3D) measurement of absorbed dose in tissue-equivalent dosemeter phantoms. Gel phantoms are imaged using optical techniques. In neutron capture therapy, properly designed gel dosemeters can give 3D dose distributions, due to the various components of the secondary radiation, in phantoms exposed in the thermal or epithermal column of a nuclear reactor. In addition to the therapeutic dose arising from the reaction 10B(n,a)7Li, the other dose components are also obtainable, i.e. the gamma dose (due to reactor background and to the reaction 1H(n,gamma)2H of thermal neutrons with hydrogen), the dose due to protons emitted in the reaction 14N(n,p)14C of thermal neutrons with nitrogen and the dose due to recoil protons resulting from elastic scattering of epithermal neutrons.

The perovskite-like KMgF3 shows, when properly doped, thermoluminescence (TL) characteristics that make this phosphor a good candidate for ionising radiation dosimetry. With the purpose of inspecting the dosimetric potentiality of such material, the thermoluminescence emission from irradiated samples of variously doped KMgF3 in the form of single crystals has been investigated. The features displayed by fluoroperovskite doped with rare earth impurities are particularly promising, in particular Ce and Yb. The results obtained with KMgF3:Yb single crystals in particular are described. The TL emission relative to temperature was inspected by means of laboratory-made instrumentation, giving also the possibility of wavelength resolution. The TL emission shows a sharp peak at 410 nm, well centred in the wavelength range of the standard TLD readers; the emission intensity is one order higher than that of TLD-700 chips. The emission was inspected in the dose range from 2 mGy to 20 Gy.

Neutron capture therapy (NCT) is based on the localised release of energy in tumours from appropriate nuclei bombarded by slow neutrons. It is proposed to measure the spatial dose distribution for some selected nuclei having very large interaction cross sections with neutrons, for different concentrations and concentration gradients, for different geometries and for different neutron beams. To this purpose, it is planned to use a three-dimensional and tissue-equivalent phantom acting as a continuous dosemeter. The dosemeter is a gel solution of ferrous sulphate: the concentration of ferric ions produced by irradiation and correlated to the dose is deduced from the measurement of the proton relaxation times by means of a clinical NMR imaging system. The dosemeter can be used in a mixed field of ? rays, neutrons and heavy particles. As a first step, the response of the gel system to ? rays and slow neutrons was measured.

The aim of this study is to establish whether striae in obese children could be considered as a disturbance of adrenal function and/or collagen synthesis and is related to higher risks of developing cardio-vascular disease. We studied 13 obese children with striae and 11 obese children without striae matched for age and weight excess. The patients were classified according to the distribution of the striae in 2 groups: A. limbs or trunk; B. limbs and trunk. In all patients the following parameters were evaluated: height and weight, pubertal stage, weight excess according to the Tanner's Standards, triceps and subscapular skinfolds, waist/hip ratio, systolic and diastolic blood pressure, blood glucose and IRI before and 120' after oral glucose load, BUN, blood uric acid, cholesterol, HDL cholesterol, triglycerides, Apo A1, Apo B, ACTH, DHEA-S, cortisol, estrone and procollagen type III propeptide (PIIIP-RIA), which is a precursor of soft connetive tissue collagen (type III). The caloric and nutrients intake was also evaluated on the basis of a three days alimentary recall.The main results, reported in the table above, suggest that striae in obese children are associated with lower collagen synthesis. Since adrenal function was similar in all groups of patients, the higher estrone blood levels in obese with striae may be due to aromatase activity of fat tissue.

6LiF enhanced dosemeters exposed to high fluences of thermal neutrons undergo irreversible radiation damage, preventing their subsequent utilisation. 6LiF depleted dosemeters do not show such an effect, but in mixed fields of high fluxes with thermal neutrons they do not provide a simple way of discriminating among the contributions of the field components. The responses to thermal neutrons and to gamma rays of some TL single crystals have been investigated. LiF:Mg,Cu,P and LiF:Cu2+ single crystals have shown a much higher sensitivity to thermal neutrons than to gamma rays. KMgF3, although promising for other dosimetry purposes, shows no useful features in such radiation fields.

In recent radiotherapy techniques, such as boron neutron capture therapy (BNCT) and proton therapy, the high non-uniformity of the spatial distribution of absorbed dose makes mandatory 3-D dose determinations in order to carry out good treatment planning. The investigated dosimetric technique is based on a chemical dosemeter (ferrous sulphate solution) incorporated in a gel (agarose). Ionising radiation causes a variation in certain parameters of the system such as the relaxation rates of hydrogen nuclei, measurable by nuclear magnetic resonance imaging (NMR) or the gel optical absorption in the visible spectum, measurable by spectrophotometry. Gel containing 10B in the amount typically accumulated in tumours for BNCT was analysed. The isodose curves were obtained from NMR analysis of a phantom of borated gel after irradiation in the thermal column of a nuclear reactor. The results show that the gel is a promising dosimetric system. A method for depth-dose profiling in tissue irradiated by a proton beam is also suggested. In the profile the Bragg peak position has been determined within 0.1 mm and the widening in the peak ramp proves to be about 1 mm.