Digital Radiography for Determination of Primary Tooth Length: In Vivo

Background. Methods for determining the root canal length of the primary tooth should yield accurate and reproducible results. In vitro studies show some limitations, which do not allow their findings to be directly transferred to a clinical situation. Aim. To compare the accuracy of radiographic tooth length obtained from in vivo digital radiograph with that obtained from ex vivo digital radiograph. Method. Direct digital radiographs of 20 upper primary incisors were performed in teeth (2/3 radicular resorption) that were radiographed by an intraoral sensor, according to the long-cone technique. Teeth were extracted, measured, and mounted in a resin block, and then radiographic template was used to standardise the sensor-target distance (30 cm). The apparent tooth length (APTL) was obtained from the computer screen by means of an electronic ruler accompanying the digital radiography software (CDR 2.0), whereas the actual tooth length (ACTL) was obtained by means of a digital calliper following extraction. Data were compared to the ACTL by variance analysis and Pearson’s correlation test. Results. The values for APTL obtained from in vivo radiography were slightly underestimated, whereas those values obtained from ex vivo were slightly overestimated. No significance was observed (P≤0.48) between APTL and ACTL. Conclusion. The length of primary teeth estimated by in vivo and ex vivo comparisons using digital radiography was found to be similar to the actual tooth length

Synthesis and optical and structural characterization of Ce(1-x)O2:MxO(M=Cu, Co) pigments

The synthesis of pigments from the system Ce1-x O2-M x O (M = Cu, Co) was achieved via a polymeric precursors method, Pechini method. Differential scanning calorimetry (DSC) and thermogravimetry (TG) techniques were used to accurately characterize the distinct thermal events occurring during synthesis. The TG and DSC results revealed a series of decomposition temperatures due to different exothermal events, which were identified as H2O elimination, organic compounds degradation, and phase formation. X-Ray diffraction patterns show the presence of pure cubic CeO2 phase for the samples with low Cu and Co loading. A decrease of the specific surface area with increasing copper and cobalt content was observed. The UV-visible diffuse reflectance technique was employed to study the optical properties in the 200-800 nm range. Colorimetric coordinates L*, a*, b* were calculated for the pigment powders. The powders presented a variety of colors from yellow for pure CeO2, to brown for the ones loaded with copper and gray for the ones with cobalt.FAPESPCAPESCNP

Chemical characterization of the stained glass window from the rose window, Siena Duomo (Italy, 1288-1289)

[EN] The chemical composition of nine medieval coloured stained glasses from Duomo (Catedral) of Siena, Italy, has been characterized. They come from the rose window elaborated under the drawing of Duccio di Buoninsegna masterwork (1288- 89 AD). This note explains the results obtained by EMPA, representative of bulk chemistry of several coloured glasses (deep green, olive green, yellow, purple, pink, deep blue, light blue, red plaqué and also uncoloured), as well as the associated trace elements (obtained by Induced Coupled Plasma Mass Spectrometry) that represent the chemical fingerprint of these glasses. The studied samples are sodium-calcium glass (chemical compositions in the range 13-14 wt% Na2O, 56-64 wt% SiO2, 4 wt% MgO, 9-10 wt% CaO, 2,5-4 wt% K2O); thus of Mediterranean tradition.This fact has been found by our team in previous studies (stained glasses from the church of Monestir de Pedralbes, Barcelona) for XIV century glass made at least 40 years later. As a general rule, the conservation state of these sodium glasses is good, except for the cohesion of grisaille to glass mesostase. This study allowed to identify three glass groups developed from different raw material formulations: a first group is constituted by deep green, olive green, light blue and yellow glass; a second one comprises by uncoloured, deep purple, deep blue and pink glass; and finally, the plaqué red glass that shows deeply different composition. Pink and yellow glass was produced following the traditional recipe compiled by Theophilus, a monk who lived at the beginning of XII century. This implies a separate process of raw material purification and a careful control of the redox kiln conditions; thus, these glasses can be considered as traditional or technologically not evolved. The deep blue, light blue and deep purple were obtained after the artisan dosed addition of a cobalt salt. Olive green and deep green glasses were produced with addition of copper (together with manganese and iron), previously prepared as a pigment that has as excipient a potassium glass. The use of potassium glass instead of the sodium glass locally produced strongly suggests that the pigment could be bought directly from Middle or Northern Europe markets and/or could be a sub-product of copper ore melting. On the other hand, the production of sodium red ruby plaqué glass, technologically more evolved and comparable to the coeval potassium glass coming from the Central Europe glass factories, would be outstanding in the XIV century; but we interpret (taking into account its chemical composition) that was produced later and introduced during the restoration conducted at the end of XVII century. We can also note the use of well-dosed lead additions in order to increase the lightness and transparency of coloured glass. Manganese has been a very important element in the Siena workshop glassmaker colour palette achievements. On the other hand, the trace-element chemical fingerprint of the glass allows arguing what kind of mineral salts were used as pigments, as well as the way to introduce it in the uncoloured original glass.[ES] Se han caracterizado químicamente una colección de vidrios arquitectónicos coloreados originales del rosetón del Duomo (catedral) de Siena, Italia, realizados bajo diseño del artista Duccio di Buoninsegna en 1288-89. Esta comunicación expone los resultados obtenidos mediante el empleo de microsonda electrónica de Castaing (mayoritarios) y espectrometría de masas con fuente de plasma acoplado inductivamente (ICP-MS, elementos en traza) en vidrios de varios colores (incoloro, verde oscuro, verde oliva, amarillo, violeta, rosa, azul oscuro, azul celeste, rojo plaqué). Se trata de vidrios sódico-cálcicos (valores en peso alrededor del 13-14 % de Na2O, 56-64 % SiO2, 4% MgO, 9-10 % CaO, 2,5-4 K2O) de tradición por tanto mediterránea. Un resultado semejante se encontró precedentemente para vidrios realizados a lo largo del siglo XIV, cuanto menos unos 40 años después (vidriera de la iglesia del Monestir de Pedralbes, Barcelona). En general, el estado de conservación de estos vidrios es bueno, excepto por lo que se refiere a la adherencia de las grisallas al vidrio base. El estudio desarrollado ha permitido identificar tres grupos de vidrios desarrollados a partir de formulaciones de diferentes composiciones: un primer grupo constituido por los vidrios de color verde claro, verde oscuro, azul celeste y amarillo; un segundo grupo constituido por los vidrios incoloro, violeta, azul oscuro, y malva; y finalmente el vidrio rojo plaqué, de composición netamente diferente a todos los demás. Desde el punto de vista de la obtención de los colores, cabe destacar que los datos químicos permiten deducir que el malva y el amarillo han sido elaborados siguiendo la receta tradicional del monje Theophilus de inicios del siglo XII, utilizando un proceso de purificación especial de las materias primas, y controlando artesanalmente las condiciones redox del horno; en este sentido, estos vidrios se pueden calificar como tradicionales o tecnológicamente poco evolucionados. Los colores azul oscuro, violeta y azul celeste se han obtenido mediante la adición de una misma sal de cobalto en diferentes dosis, y los colores verde oliva y verde oscuro mediante la adición de cobre (junto con manganeso y hierro), previamente preparados en un colorante que tiene como excipiente un vidrio potásico. Este último hecho (el empleo de vidrio potásico no usual en los centros productores del área mediterránea) permite suponer que el color puede haber sido comprado directamente a un fabricante centroeuropeo o que se tratara de un subproducto de fundición de minerales de cobre. Por su parte, la fabricación del vidrio plaqué, tecnológicamente más complejo y comparable al vidrio rojo plaqué potásico centroeuropeo contemporáneo indicaría, si fuera original, la incorporación de este proceso tecnológico al taller local. En opinión de los autores se trata de un vidrio de producción local mucho más tardia, incorporado en la restauración documentada a finales del siglo XVII. Destaca también, como en Pedralbes, el empleo del plomo para aumentar la luminosidad y transparencia del vidrio, en dosis variables atendiendo al color del vidrio. Por otro lado hay que señalar que en Siena el manganeso es un elemento muy importante con el que el fabricante del vidrio jugó intensamente para obtener la paleta de colores. El análisis de los metales presentes como elementos traza, y de las tierras raras, permite establecer sólidas hipótesis sobre el tipo de sales minerales empleadas como colorantes y como fueron incorporados al vidrio incoloro original.Este trabajo se ha podido realizar en el marco de diferentes proyectos financiados (proyecto 3338 de la Fundació Bosch i Gimpera, UB; acción integrada hispano-italiana HI2006-0190: La producción y el comercio del vidrio plano en Europa y en el Mediterráneo Occidental, entre los siglos XI y XV: un estudio arqueométrico) . La caracterización geoquímica de los vidrios mediante MSE e ICP-MS se ha llevado a cabo en los Serveis Científico-Tècnics de la Universitat de Barcelona (SCT-UB);Peer reviewe

Mutations in TGM6 induce the unfolded protein response in SCA35

Spinocerebellar ataxia type 35 (SCA35) is a rare autosomal-dominant neurodegenerative disease caused by mutations in the TGM6 gene, which codes for transglutaminase 6 (TG6). Mutations in TG6 induce cerebellar degeneration by an unknown mechanism. We identified seven patients bearing new mutations in TGM6. To gain insights into the molecular basis of mutant TG6-induced neurotoxicity, we analyzed all of the seven new TG6 mutants and the five TG6 mutants previously linked to SCA35. We found that wild-type (TG6-WT) mainly localized to the nucleus and perinuclear area, whereas five TG6 mutations showed nuclear depletion, increased accumulation in the perinuclear area, insolubility and loss of enzymatic function. Aberrant accumulation of these TG6 mutants in the perinuclear area led to activation of the unfolded protein response (UPR), suggesting that specific TG6 mutants elicit an endoplasmic reticulum (ER) stress response. Mutations associated with activation of the UPR caused death of primary neurons and reduced the survival of novel D. melanogaster models of SCA35. These results indicate that mutations differently impacting on TG6 function cause neuronal dysfunction and death through diverse mechanisms and highlight the UPR as a potential therapeutic target for patient treatment

Estudo da cinética de remoção de Manganês utilizando carvão ativado impregnado com óxido de Manganês / Study of manganese removal kinetics using manganese oxide impregnated activated carbon

 A fim de avaliar a cinética de remoção de manganês em um minirreator de leito fixo, recheado com carvão ativado impregnado com óxido de manganês, foram efetuados ensaios em diversas vazões de alimentação e concentrações iniciais de Mn2+, medindo-se a concentração na saída ao longo do tempo. Percebeu-se uma rápida desativação inicial nos primeiros 30 minutos, seguida por um longo período de operação estável em regime estacionário, no qual a cinética da reação, tipo lei de potências ( ), foi avaliada. Constatou-se que a ordem da reação foi de 0,83 e a constante de velocidade de 1,27 E-5 m 2,49mol 0,17 kg -1s-1.

Isolated Hepatocyte Transplantation for Crigler-Najjar Syndrome Type 1:

Crigler-Najjar syndrome type 1 (CN1) is an inherited disorder characterized by the absence of hepatic uridine diphosphoglucuronate glucuronosyltransferase (UDPGT), the enzyme responsible for the conjugation and excretion of bilirubin. We performed allogenic hepatocyte transplantation (AHT) in a child with CN1, aiming to improve bilirubin glucuronidation in this condition. A 9-year-old boy with CN1 was prepared with plasmapheresis and immunosuppression with prednisolone and tacrolimus. When a graft was made available, 7.5 × 10 9 hepatocytes were isolated and infused into the portal vein percutaneously. After 2 weeks phenobarbitone was added to promote the enzymatic activity of UDPGT of the transplanted hepatocytes. Nocturnal phototherapy was continued throughout the studied period. Total bilirubin was considered a reliable marker of allogenic cell function. There was no significant variation of vital signs nor complications during the infusion. Mean ± SD bilirubin level was 530 ± 38 µmol/L before and 359 ± 46 µmol/L after AHT (t-test, p < 0.001). However, the introduction of phenobarbitone was followed by a drop of tacrolimus level with increase of alanine aminotransferase (ALT) and increase of bilirubin. After standard treatment of cellular rejection bilirubin fell again but from then on it was maintained at a greater level. After discharge the patient experienced a further increase of bilirubin that returned to predischarge levels after readmission to the hospital. This was interpreted as poor compliance with phototherapy. Only partial correction of clinical jaundice and the poor tolerability to nocturnal phototherapy led the parents to refuse further hepatocyte infusions and request an orthotopic liver transplant. After 24 months the child is well, with good liver function on tacrolimus and prednisolone-based immunosuppression. Isolated AHT, though effective and safe, is not sufficient to correct CN1. Maintenance of adequate immunosuppression and family compliance are the main factors hampering the success of this procedure

CeO2 nanoparticles synthesized by a microwave-assisted hydrothermal method: evolution from nanospheres to nanorods

Ceria (CeO2) plays a vital role in emerging technologies for environmental and energy-related applications. The catalytic efficiency of ceria nanoparticles depends on its morphology. In this study, CeO2 nanoparticles were synthesized by a microwave-assisted hydrothermal method under different synthesis temperatures. The samples were characterized by X-ray diffraction, transmission electron microscopy, Raman scattering spectroscopy, electron paramagnetic resonance spectroscopy and by the Brunauer-Emmett-Teller method. The X-ray diffraction and Raman scattering results indicated that all the synthesized samples had a pure cubic CeO2 structure. Rietveld analysis and Raman scattering also revealed the presence of structural defects due to an associated reduction in the valence of the Ce4+ ions to Ce3+ ions caused by an increasing molar fraction of oxygen vacancies. The morphology of the samples was controlled by varying the synthesis temperature. The TEM images show that samples synthesized at 80 degrees C consisted of spherical particles of about 5 nm, while those synthesized at 120 degrees C presented a mix of spherical and rod-like nanoparticles and the sample synthesized at 160 degrees C consisted of nanorods with 10 nm average diameter and 70 nm length. The microwave-assisted method proved to be highly efficient for the synthesis of CeO2 nanoparticles with different morphologies.FAPESPCNP

Advancements in ion beam figuring of very thin glass plates

The high-quality surface characteristics, both in terms of figure error and of micro-roughness, required on the mirrors of a high angular resolution x-ray telescope are challenging, but in principle well suited with a deterministic and non-contact process like the ion beam figuring. This process has been recently proven to be compatible even with very thin (thickness around 0.4mm) sheet of glasses (like D263 and Eagle). In the last decade, these types of glass have been investigated as substrates for hot slumping, with residual figure errors of hundreds of nanometres. In this view, the mirrors segments fabrication could be envisaged as a simple two phases process: a first replica step based on hot slumping (direct/indirect) followed by an ion beam figuring which can be considered as a post-fabrication correction method. The first ion beam figuring trials, realized on flat samples, showed that the micro-roughness is not damaged but a deeper analysis is necessary to characterize and eventually control/compensate the glass shape variations. In this paper, we present the advancements in the process definition, both on flat and slumped glass samples

Progress in ion beam figuring of very thin slumped glass plates for lightweight x-ray telescope

The combination of the hot slumping and the Ion Beam Figuring (IBF) technologies can be a very competitive solution for the realization of x-ray optics with excellent imaging capabilities and high throughput. While very thin mirrors segments can be realized by slumping with residual figure errors below few hundreds of nanometres, a non-contact and deterministic process (dependent on dwell time), like IBF, is a very effective post facto correction, as it avoids all the problems due to the handling and the supporting system. In the last years, the two processes were proven compatible with very thin sheet of Eagle XG glasses (0.4 mm thickness). Nevertheless, the fast convergence of the process is a key factor to limit the cost of the mirror plate production. A deeper characterization of removal function stability showed that its repeatability between each run has to be improved for a real enhancement of the process convergence factor. A new algorithm based on de-convolution has been implemented and tested, with important advantages in terms of calculation speed, minimum material removal and optimization possibilities. By analysing the metrological data of test slumped glasses, we showed how the IBF is effective in the correction of figure errors on scales above 8 - 10 mm. An overall figuring time of few hours is required with surface error around 100 nm rms. Thanks to the thickness measurement data, which are performed in transmission mode with an interferometric set-up, we demonstrated that it is possible to disentangle the effective amount of the material removed and the deformations introduced during the process

Lynx optics based on full monolithic shells: design and development

Lynx is an X-ray mission concept with superb imaging capabilities (2 effective area @1keV). Several approaches are being considered to meet the challenging technological task of the mirror fabrication. Thin and light substrates are necessary to meet mass constraints. Monolithic fused silica shells are a possible solution if their thickness can be maintained to below 4 mm for mirror shells up to 3 m diameter. In this paper we present the opto-mechanical design of the mirror assembly, the technological processes, and the results achieved so far on a prototypal shells under development. In particular, emphasis is placed on the figuring process that is based on direct polishing and on ion beam figuring and on a temporary stiffening structure designed to support the shell during the figuring and polishing operations and to manage the handling of the shell through all phases up to integration into the telescope supporting structure