Laser Cladding-based metallic embedding technique for fiber optic sensors

IEEE In many applications in industry, securely attaching fiber optic sensors to metallic structures is important for optimum monitoring, overcoming the limitations of glues and adhesives which are known to degrade under certain circumstances. To avoid that problem, creating a metallic bond to attach the sensors securely to the metal surface is important. Commercial fiber optics with metal coatings can be used but it is important not to damage the sensor itself which is written in the thin optical fiber. In this work an alternative laser cladding technology has been studied for embedding metal coated fiber optics into which Fiber Bragg Grating (FBG) sensors have been written. A three-step strategy was selected for embedding the metal coating fibers to create the best conditions to allow high quality measurements to be made. This has been seen to allow good control of the embedding process to be achieved and to minimize the thermal and mechanical stress generated. The research undetaken has shown that it is possible to embed Cu and Ni coated fiber optics containing sensors to over 300 & #x03BC;m with low losses, of between 0-1.5 dB (or 0-30%) and yet still enable satisfactory strain and temperature measurement results to be obtained. The research has shown that both Ni and Cu coated FBG-based fiber optic sensors could be embedded successfully and shown to give good mechanical and thermal response to similar non-embedded sensors and give excellent cross-comparison with the conventional gauge used for calibration. The results are therefore particularly encouraging for the use of sensors of this type when incorporated to create metallic & #x2018;smart structures & #x2019; achieving durability of the sensors through the use of this innovative technique

Técnicas de imagen para la valoración del estado ganglionar axilar en el cáncer de mama

The axillary lymph node status is the most important prognostic factor in breast cancer, and the axillary dissection as the gold standar for staging. It requires radical surgery, which is accompanied by importants postoperaive problems. Axillary lymph nodes can be imaged with a wide variety of available diagnostic radiological test (ultrasonography, mammography, computed tomography and magnetic resonance imaging). In these anatomic imaging, the limph nodes whit metastatic disease appear dense, enlarged or spiculated. Difficulties arise, not in visualization of the axillary lymph nodes, but in reliably separating normal from those involved with metastatic disease. Radionucleide studies and positron emisión tomography provide biochemical information, but are limited by resolution constrains

Técnicas de biopsia para el diagnóstico de lesiones mamarias no palpables

Facing a non-palpable mammary lesion requiring a diagnostic biopsy, consideration must be given to the most suitable guiding method for obtaining the latter. Three methods are employed at present: stereotaxy (basically in cases of microcalcifications), echography (above all in the nodules), and magnetic resonance (for lesions not made visible through the previous systems). The next step is to select the most suitable biopsy technique. The most classical and reliable technique is the surgical biopsy with prior marking using a metallic harpoon, but, besides its high cost, it has the drawback of being an aggressive technique for the diagnosis of a benign pathology. Numerous systems of puncture have been developed as alternatives. Puncture with a fine needle is technically simple to carry out and can provide good results in the mammary nodules, but the existence of positive and negative false results has progressively limited its use. As an alternative, the systems of biopsy with a broad needle have made it possible to obtain multiple cylinders with a high diagnostic reliability, above all in the case of mammary nodules. However, their use in microcalcifications continues to show negative false results. The arrival of systems of vacuum-assisted biopsy has made it possible to obtain cylinders of greater quality, above all in cases of microcalcifications. Finally, the systems of percutaneous resection biopsy by means of cannulas with a diameter of 22 mm make it possible to completely extract lesions of a size below that of the cannula, with a reliability similar to that of the surgical biopsy

Lesiones mamarias no palpables: Biopsia por congelación

Introducción: El interés prioritario del examen microscópico intraoperatorio de una biopsia de mama es la obtención del diagnóstico histológico; pero en el caso de lesiones malignas, también es importante el conocer el estado de los márgenes de resección quirúrgica, con objeto de realizar en un sólo acto quirúrgico el tratamiento definitivo. Material y Métodos: Se revisan 215 biopsias por congelación correspondientes a lesiones mamarias no palpables (LNP), practicadas bajo control de arpón marcador; seguidas posteriormente durante 36 meses. El espécimen obtenido, una vez marcado en sus bordes (orientación de la pieza) fue teñido con tinta china y radiografiado. Tras ser cortado de forma seriada, fue nuevamente radiografiado, lo que permitió seleccionar el/los cortes que serán sometidos a estudio morfológico por congelación. Resultados: el 53,9% de las LNP biopsiadas correspondían a microcalcificaciones, 31,6 densidades anormales y 14,6 presentaban densidades anormales asociadas a microcalcificaciones. En 110 casos se trató de carcinomas. En 11 casos la biopsia por congelación no permitió un diagnóstico definitivo que debió diferirse hasta el estudio en parafina. No existieron falsos positivos, y en 5 casos (2,3%) el diagnóstico definitivo difirió del intraoperatorio. En otros 5 casos el estudio en parafina advirtió de la afectación de los bordes de resección siendo precisa una nueva intervención quirúrgica. Conclusiones: La biopsia por congelación en el caso de LNP permite no sólo el diagnóstico morfológico, sino en la mayoría de los casos asegurar el estado de los márgenes de resección evitando una nueva intervención quirúrgica.Background: The priority in the examination of breast biopsies is to obtain a histologic diagnosis, but in NPL it is also important to know the whether the surgical margins are involved, so that definitive surgery may be carried out. Methods: A review of 215 consecutive needle-located biopsies was carried out. Median follow-up was 36 months. The surgical specimen was dyed, radiographed and serially sectioned. After a further radiography, the section of tissue with the lesion area closer to the resection margin was histopathologically studied by freezing. Results: 53.9% of NPL were calcifications, 31.6% were abnormal density, and 14.6% presented density asso- ciated with calcifications. 110 cases were carcinomas. 11 cases were classified as "non diagnostic" with frozen section and the diagnosis was deferred to permanent sections. A false-negative diagnosis was made in 5 cases (2.3 %); there were no false-positive diagnoses. In 5 cases the margin involvement was evidenced with paraffin study, and a second operation was needed to perform wider margin excisions. Conclusions: The intraoperative frozen section of NPL provides an accurate diagnosis even with small speci- mens, thus avoiding a second surgical procedure

Función de apantallamiento de interferencia electromagnética de pastas de cemento con materiales carbonosos y cenizas volantes procesadas

The study described in this article explored the effect of adding different types of carbon materials (graphite powder and three types of carbon fibre), fly ash (with 5.6%, 15.9% and 24.3% Fe2O3), and a mix of both on electromagnetic interference (EMI) shielding in Portland cement pastes. The parameters studied included the type and aspect ratio of the carbonic material, composite material thickness, the frequency of the incident electromagnetic radiation and the percentage of the magnetic fraction in the fly ash. The findings showed that the polyacrylonitrile-based carbon fibres, which had the highest aspect ratio, provided more effective shielding than any of the other carbon materials studied. Shielding was more effective in thicker specimens and at higher radiation frequencies. Raising the magnetic fraction of the fly ash, in turn, also enhanced paste shielding performance. Finally, adding both carbon fibre and fly ash to the paste resulted in the most effective EMI shielding as a result of the synergies generated.En el presente trabajo se investiga la influencia de la adición de diferentes tipos de materiales carbonosos (polvo de grafito y 3 tipos de fibra de carbono), de una ceniza volante con diferentes contenidos de fase magnética (5,6%, 15,9% y 24,3% de Fe2O3) y de una mezcla de ambos, sobre la capacidad de apantallar interferencias electromagnéticas de pastas de cemento Pórtland. Entre los parámetros estudiados se encuentra: el tipo de material carbonoso, la relación de aspecto del material carbonoso, el espesor del material compuesto, la frecuencia de la radiación electromagnética incidente y el porcentaje de fracción magnética en la ceniza volante. Los resultados obtenidos indican que entre los materiales carbonosos estudiados son las fibras de carbono basadas en poliacrilonitrilo con una mayor relación de aspecto las que dan mejores resultados de apantallamiento. Al aumentar el espesor del material compuesto o la frecuencia de radiación también aumenta la eficacia del apantallamiento. En lo que respecta a la ceniza volante, el incremento de la fracción magnética de la ceniza incrementa el nivel de apantallamiento. No obstante, los resultados más eficaces se obtienen por la adición conjunta de fibras de carbono y ceniza volante debido a un efecto sinérgico

Archaeological ceramic amphorae from underwater marine environments: Influence of firing temperature on salt crystallization decay

Non-desalinated and desalinated fragments of Iberian, Italic and Tarraconensian amphorae sherds, found in different underwater marine environments, were compared to determine the decay caused by salt crystallization. Polarizing light and fluorescence optical microscopy, scanning electron microscopy coupled to energy dispersive X-ray spectroscopy, X-ray diffraction, ion chromatography and mercury intrusion porosimetry tests were conducted on the samples. Non-desalinated samples exhibit a variety of signs of degradation, especially those samples fired at lower temperature. Sherds fired at higher temperatures have a lower surface area and less connected porosity, which entail a lower absorption of soluble salts containing water and eventually less decay than those fired at lower temperatures. The composition and texture reached with the firing temperature is a key factor on salt crystallization decay and hence on the durability of these artefacts. This should be taken into account during desalination procedures that have to be optimized in order to be successful

Tratamiento conservador del cáncer de mama: valoración de los resultados

Introducción: La asociación de cirugía limitada y radioterapia es el tratamiento de elección para un gran número de mujeres con cáncer de mama; no obstante esta opción terapéutica va asociada a un número no despreciable de recidivas sobre la mama tratada (1-1,5% por año de seguimiento). Material y Métodos: Se analizan 641 casos de mujeres con cáncer de mama, tratados mediante cirugía conservadora de la mama y radioterapia y seguidos durante una media de 50 meses. La técnica consistió preferentemente en la practica de una Resección Segmentaria de mama con vaciamiento axilar, al menos de los niveles I y II (excepto en los CIS a partir de 1997), complementada con la administración de Radioterapia (45-50 Gy sobre la mama y una sobreimpresión de 15-20 Gy). Resultados: La edad media fue de 52.3 años, con extremos en 21 y 82 años El tamaño medio tumoral fue pT: 1,7 cm y el 63,1% de los casos correspondieron a tumores pT1. En 41 casos no se realizó vaciamiento axilar (35 CIS y 6 pT1mic). En 4 casos existió afectación puntual de bordes (componente intraductal) que fueron sometidos a sobreimpresión radioterápica con 20Gy. Tras un seguimiento medio de 50 meses, el 91,4% están libres de enfermedad y en 12 casos (1,9%) se desconocía su estado. Se han producido 13 recidivas (2%) a nivel mamario (2 de ellas en un cuadrante distinto). Conclusiones: El estado de los bordes de resección en un factor fundamental en la cirugía conservadora del cáncer de mama. La resección del tumor debe ser suficientemente amplia e incluir el segmento mamario asiento del tumor, para asegurar un alto índice de control local, sin comprometer el resultado cosmético. El estudio histológico de los bordes de resección permite reducir significativamente la necesidad de una segunda cirugía.Introduction: Conservative surgery combined with radiotherapy is an effective treatment in many cases of breast cancer. Nevertheless this therapy is associated with a not inconsiderable number of recurrences in the remaining breast after excision (1-1.5% recurrences per year of follow-up). Material and Methods: We reviewed 641 cases of breast cancer (age average was 52.3 years (21-82) and tumour size average 1.7 cm, 3% corresponded to pT1 tumours) treated with conservative surgery combined with radiotherapy, average follow-up of 50 months. The technique consisted of segmentectomy and at least level I-II axilary dissection (excluding in situ carcinoma diagnosed since 1997, in which lymphadenectomy was not performed). Adjuvant radiotherapy was also indicated (giving a dose of 45-50 Gy to the breast, and another 15-20 Gy dose was given to tumour size). Results: In 41 cases lymphadenectomy was not performed (35 cases of Tis, and 6 pTmic). In 4 cases, 20 Gy radiotherapy was administered to the tumour excision site because of in situ carcinoma disease in the margins. During follow-up of 50 months, 91.4% of the patients were disease- free; in 12 cases we are not informed of the present status. 13 recurrences (2%) have been found, two of which were in a different quadrant. Conclusions: The status of the surgical margins is an important factor in the practice of conservative surgery. Tumour excision must be broad enough and must include the whole segment in which the tumour is located to obtain local control of the disease, maintaining an acceptable cosmetic appearance. The intraoperative study of specimen margins permits the reduction of cases in which a second operation is needed

Secuelas tras inyección ilegal de silicona líquida como técnica de aumento mamario: presentación de 2 casos

The use of liquid silicone for breast augmentation was widespread in the 1960s but was abandoned at the end of the decade due to numerous studies describing the development of a large number of local complications, as well as remote migration of small amounts of silicone. The use of liquid silicone also leads to enormous difficulty in the early diagnosis of breast cancer; these patients are precluded from routine screening programs and must undergo exhaustive periodic examinations. Magnetic resonance imaging has become the most effective test for the early detection of breast cancer in these patients. Indications for subcutaneous mastectomy are the presence of local complications, suspicion of a malignant lesion, or the patient’s desire to prevent both these potential problems