Determination of gold in alloys via potentiometric titration; an alternative to the fire assay

In this paper we report the results of a deep investigation of gold title in jewellery alloys by means of potentiometric titration. After reviewing the suitable reactions for such purpose we focused on the most profitable one, which involves the use of hexadecylpyridinium chloride (CPC). This cation gives rise to selective and quantitative precipitation of AuCl4 −. We completely revised a method previously proposed by W.S. Selig in the 80's, by improving the sampling preparation and by optimizing the titration steps. Then, the new proposed method was tested on a large number of different alloys, commonly used for goldsmithery purposes. The obtained gold titles were compared with the data achieved by fire assay, giving rise to a very good agreement. At the light of these results, the present method can be rightfully considered a cheaper and "greener" alternative to the traditional one

Testicolo non palpabile nell’adulto: trattamento laparoscopico

Il criptorchidismo ha un’incidenza variabile fra lo 0,8% e il 2% nella popolazione generale; nel 20% dei casi il testicolo non è palpabile. Questi ultimi casi hanno un aumentato rischio di trasformazione maligna, infertilità e malformazioni epididimali. Il trattamento chirurgico dei testicoli ritenuti non palpabili ha più elevate percentuali di fallimento se paragonato ai casi palpabili. Sono state descritte diverse procedure diagnostiche, di cui la più promettente sembra essere la laparoscopia per la maggiore affidabilità rispetto alle tecniche di imaging nell’individuare la sede del testicolo ritenuto

A rare case of blunt thoracoabdominal trauma with small bowel perforation from airbag

Vehicle collisions represent more than 75% of mechanism of blunt abdominal trauma. In spite of the incomparable improvement of car safety devices, recent studies pointed out that the airbag might cause injuries, specially when it is not associated with seatbelt. In fact, some studies pointed out that crash victims using airbag alone have increased injury severity, hospitalisations, thoracoabdominal procedure, and rehabilitation. Some of the most frequently injured organs reported from airbag deployment are the liver (38%), the spleen (23%) and digestive system (17%). Injury of the hollow viscera are far less common. In particular, blunt abdominal trauma resulting in small bowel perforation is an infrequent lesion. These injuries are difficult to diagnose because specific signs are poor and a delay in treatment increases mortality and morbidity of the patients. We describe a case of thoracoabdominal trauma occurred during a head-on collision after an airbag deployment without seatbelt us