A. Calderón

Thermal Diffusivity in Bone and Hydroxyapatite

We report thermal diffusivity measurements in bull bone and commercial hydroxyapatite (HA), both in powder form, in order to determinate the thermal compatibility between these materials. Besides this, we report a comparison between these measured values and those of metallic samples frequently used in implants, as high purity titanium and stainless steel. Our results show a good thermal compatibility (74%) between HA and bone, both in powder form. Finally, it was obtained a one order of magnitude difference between the thermal diffusivity values of metallic samples and those corresponding values to bone and HA being this difference greater in titanium than in stainless steel, which is important to consider in some biomedical and dental applications.

Fasciola hepatica in the common bile duct: spyglass visualization and endoscopic extraction

We report the case of a 60-year-old Peruvian female who was admitted with abdominal pain and jaundice. Cholangioscopy revealed a leaf-like trematode, Fasciola hepatica. This trematode was extracted with a Dormias basket via endoscopic retrograde cholangiopancreatography (ERCP).We report the case of a 60-year-old Peruvian female who was admitted with abdominal pain and jaundice. Cholangioscopy revealed a leaf-like trematode, Fasciola hepatica. This trematode was extracted with a Dormia’s basket via endoscopic retrograde cholangiopancreatography (ERCP)

Photothermal pump-probe lock-in shadowgraph technique using a thermographic camera for thermal diffusivity measurement in thin metallic filaments

We present a method for measurement of the thermal diffusivity of metallic samples in the form of thin filaments, which is inspired in both the photothermal beam deflection and the shadowgraph techniques. The method utilizes the shadow projected by the sample when put against a collimated light source (a probe beam). The sample is then heated periodically by another light beam (the pump beam), giving rise to thermal waves, which propagate across it and through its surroundings. Changes in the refraction index of the surrounding media due to the heating distort the shadow. The periodical time evolution of the shadow is recorded by a FLIR SC2500 Infrared Camera and lock-in amplified in order to determine the sample ́s thermal diffusivity by the well-known phase slope method.

Endoscópic Peri Pancreatic Fluid Collection Drainage Guided by USE in a Highly Complex Hospital in Lima, Peru. A First National Case Series

Endoscopic drainage of pancreatic and peri pancreatic mature collections guided by USE actually is recognized as an alternative to other therapeutic modalities such as percutaneous and surgical interventions, because it is safe and achieves high success rates, being higher for pseudocysts. In this case series, we describe our initial experience in transmural endoscopic ultrasound guided drainage carried out with biliary plastic double pigtail stents in five patients with this type of collections secondary to acute pancreatitis.

Microstructure and Thermal Characterization of Dense Bone and Metals for Biomedical Use

We present a microstructural study and thermal diffusivity measurements at room temperature in two different sections of bull dense bone, bull bone and commercial hydroxyapatite, the last two in powder form. A comparison was realised between these measured values and those obtained from metallic samples frequently used in implants, as high purity titanium and 316L stainless steel. Our results show that the porosity and its orientation in the bone are two important factors for the heat flux through the bone. On the other hand, we obtained that the hydroxyapatite, in compact powder form, presents a thermal diffusivity value close to those obtained for the samples of bone which gives a good thermal agreement between these materials. Finally, it was obtained at one order of magnitude difference between the thermal diffusivity values of metallic samples and those corresponding values to bone and hydroxyapatite being this difference greater in titanium than in stainless steel.

Heat diffusion in the two layer system GaAs/GaSb joined by the fusion technique

Heat difusion is study in the two layer GaAs/GaSb system. Analysis of the thermal diffusivity of these systems demostrates the rol that the union plays in heat transport in these systems as a function of the temperature used in the joining process. The termal diffusivity measurementswere carried out by mean of the photoacoustic technique in a heat transmission configuration.