New precipitation method for isolation of 99mTc from irradiated 100Mo target.

Technetium-99m is the most widely used radionuclide in nuclear medicine. This work describes the method to separate 99mTc from irradiated 100Mo target. For this purpose we utilized formation of ammonium molybdenum phosphate (AMP) and have optimized the four parameters of the process. The proposed process is promising and allows fast separation of macroamounts of molybdenum without co-precipitation of 99mTc. The concentration of molybdenum in solution after precipitation of AMP was lower than 300 µg ml-1. Additional purification using AnaLigTc-02 is required to obtain solution with lower concentration of molybdenum.

Caninos superiores retenidos por palatino: radiografía panorámica para evaluar ubicarlos en el arco dentario / Palatally impacted upper canines: panoramic radiography to assess their location in the dental arch

Los caninos superiores permanentes, estadísticamente, se encuentran entre las piezas dentarias que con más frecuencia quedan en retención ósea,después de los terceros molares.Sin embargo, los caninos, estética, funcionalmente, y para mantenimiento de las relaciones contactantes,a la hora de valorarlos en boca, desempeñan una función más importante que los terceros molares. Por eso la importancia de poder ubicarlos en el arco dentario. Cuando los ortodoncistas, sobre todo los menos experimentados, se enfrentan a la decisión de conservar los caninos que se encuentran en posiciones deretención ósea palatina, son muchos los interrogantes que se le plantean sobre su posible ubicación con éxito, en el arco dentario. Frecuentemente está la duda de cuál es el límite de la posición de retención para intentar su acomodamiento. Proponemos un simple trazado que se puede hacersobre la ortopantomografia panorámica, marcando dos líneas tangentes a la pared externa delas fosas nasales que se continuarán con los ejes longitudinales de los caninos retenidos de ambos lados. Si queda constituida una figura geométrica de apariencia de un rombo, significa que el extremo de la raíz se encuentra próximo a la posición que anatómicamente le pertenece (fosa canina del maxilar superior), existiendo una alta probabilidad de concluir con éxito su ubicación en el arco dentario.

Statiscally, permanent upper canines are the mostfrequently impacted teeth, after third molars.Upper canines though, have more significancethan third molars aesthetically, functionally andin maintaining contacting relations;thus the importance of bringing them inthe correct position within the dental arch.When an Orthodontist, particularly those lessexperienced, are faced with the decision ofmaintaining canines impacted in the palatal bone;many questions linger regarding the possibilitiesof successful relocation into the dental arch.Frequently, the question lays in the limitationsof moving it from its impacted positionto the correct one.We propose a simple tracing of theOrthopantomogram (OPG), marking twotangent lines to the lateral wall of the nasal cavitycontinuing on the long axis of the impactedcanines of both sides. If the result is a geometricfigure resembling a rhombus, it means thatthe radicular apex is close to the correctanatomical position (maxillary canine fossa),indicating high probabilities of successfullypositioning the impacted tooth.

Analytical, toxicological and kinetic investigation of decomposition of the drug diclofenac in waters and wastes using gamma radiation.

The radiolytic decomposition of the drug diclofenac (DCF), and in limited extent, also two other widely used drugs, ibuprofen and carbamazepine, was examined using liquid chromatography (LC) methods. The efficiency of DCF decomposition was examined in function of the absorbed dose of gamma radiation, and also in the presence of selected scavengers of radicals, which are commonly present in natural waters and wastes. Three different tests were employed for the monitoring of toxicity changes in the irradiated DCF solutions. The LC/mass spectrometry (MS) was used for the determination of products of DCF radiolysis. Using pulse-radiolysis method with the spectrophotometric detection, the rate constant values were determined for reactions of DCF with the main products of water radiolysis: hydroxyl radicals (1.24 ± 0.02) × 10(10) M(-1) s(-1) and hydrated electrons (3.1 ± 0.2) × 10(9) M(-1) s(-1). Their values indicate that both oxidative and reductive processes in radiolytic decomposition of DCF can take place in irradiated diluted aqueous solutions of DCF. The possibility of decomposition of all examined analytes was investigated in samples of river water and hospital waste. Compared to the previous studies, the conducted measurements in real samples were carried out at the concentration levels, which are close to those reported earlier in environmental samples. Graphical abstract ᅟ.