Enhancing heat transfer at low temperatures by laser functionalization of the inner surface of metal pipes.

The latent heat transfer during vapour condensation in the condenser section of passive heat transport devices such as the two-phase closed thermosiphon is limited by film condensation. Dropwise condensation provides an increase of the heat transfer coefficient by up to one order of magnitude and can be achieved with a water-repellant surface. The inner surface of pipes made from stainless steel was functionalized by laser surface texturing with ultrashort laser pulses and subsequent storage in a liquid containing long-chained hydrocarbons. The pipes were separated into half-pipes by wire eroding to enable laser texturing of the inner surface, and were then joined by electron beam welding after laser texturing. As a result, superhydrophobic and water-repellent surfaces with a contact angle of 153° were obtained on the inner surface of the pipes with a length of up to 1 m. The functionalized pipes were used in the condenser section of a two-phase closed thermosiphon to demonstrate a heat transfer rate of 0.92 kW at 45 °C, which is approximately three times the heat transfer rate of 0.31 kW of a smooth reference pipe.

Necrolytic migratory erythema and pancreatic glucagonoma.

Necrolytic migratory erythema is a rare paraneoplastic dermatosis that may be the first clinical manifestation of the glucagonoma syndrome, a disorder characterized by mucocutaneous rash, glucose intolerance, hypoaminoacidemia, hyperglucagonaemia and pancreatic glucagonoma. The clinical case of a 45-year-old woman is presented. She had been experiencing weight loss, polydipsia, polyphagia, postprandial emesis, excessive hair loss and abdominal pain for two months. Erythematous, scaly and migratory plaques with 20 days of evolution were found on her trunk, perineum, elbows, hands, feet, inframammary and antecubital folds. The skin biopsy revealed noticeable vacuolar changes in high epidermal cells, extensive necrosis and thin orthokeratotic cornified layer. These findings pointed to a diagnosis of necrolytic migratory erythema. A suggestion was made to investigate a pancreatic glucagonoma. Laboratory tests showed moderate anemia, hyperglycemia and marked hyperglucagonaemia. Abdominal ultrasound revealed a mass in the tail of the pancreas measuring 6 x 5 x 5 cm which was resected. The histopathological findings were compatible with a diagnosis of glucagonoma, as confirmed by immunohistochemistry. Skin symptoms disappeared 10 days after the tumor resection. We can conclude that the histological changes defined may be clues that can lead the search for a distant skin disease and allow for its diagnosis. The histological pattern of vacuolation and epidermal necrosis should arouse suspicion of pancreatic glucagonoma.

Complicaciones respiratorias en el posoperatorio de cirugía cardíaca en adultos / Respiratory complications in the postoperative period of cardiac surgery in adults / Complicações respiratórias no pós-operatório de cirurgia cardíaca em adultos

Resumen: Todos los pacientes que cursan un posoperatorio de cirugía cardíaca desarrollan alteraciones respiratorias. Por esta razón, es muy importante la implementación de todas las medidas tendientes a minimizar el impacto de estas. El verdadero desafío consiste en la detección precoz de dichas complicaciones y el desarrollo de estrategias terapéuticas tempranas con el objetivo de minimizar su impacto. En el presente trabajo, se analizan las principales complicaciones respiratorias en el escenario del posoperatorio de cirugía cardíaca y las acciones terapéuticas correspondientes.

Summary: All patients who undergo cardiac surgery develop respiratory disorders in the postoperative period. It is very important to implement all measures to minimize the impact of these alterations. The real challenge consists in the early detection of complications and the development of early therapeutic strategies in order to minimize their impact. In the present study, the main respiratory complications in the postoperative setting of cardiac surgery, and the corresponding therapeutic actions, are analyzed.

Resumo: Todos os pacientes submetidos à cirurgia cardíaca desenvolvem distúrbios respiratórios no pós-operatório. É muito importante implementar todas as medidas para minimizar o impacto dessas alterações. O verdadeiro desafio consiste na detecção precoce das complicações e no desenvolvimento de estratégias terapêuticas precoces de forma a minimizar o seu impacto. No presente trabalho, são analisadas as principais complicações respiratórias no pós-operatório de cirurgia cardíaca e as respectivas ações terapêuticas.

Eritema necrolítico migratorio y glucagonoma pancreático / Necrolytic migratory erythema and pancreatic glucagonoma

El eritema necrolítico migratorio es una dermatosis paraneoplásica infrecuente que puede ser la primera manifestación clínica del glucagonoma, el cual se caracteriza por erupción mucocutánea, intolerancia a la glucosa, hipoaminoacidemia, hiperglucagonemia y glucagonoma pancreático. Se presenta el caso clínico de una mujer de 45 años que presentó pérdida de peso, polidipsia, polifagia, vómito posprandial, caída abundante del cabello y dolor abdominal de dos meses de evolución. Tenía, además, placas eritematosas, descamativas y migratorias en tronco, periné, codos, manos, pies, pliegues submamarios y antecubitales de 20 días de evolución. En la biopsia de piel se observaron células epidérmicas altas con cambio vacuolar notorio, extensa necrosis y delgada capa córnea ortoqueratósica, hallazgos interpretados como eritema necrolítico migratorio. Se sugirió investigar un glucagonoma pancreático. En los exámenes de laboratorio se encontró anemia moderada, hiperglucemia e importante hiperglucagonemia. La ecografía abdominal reveló una masa de 6 x 5 x 5 cm en la cola pancreática, la cual fue resecada. El diagnóstico histopatológico fue de glucagonoma confirmado por inmunohistoquímica. Los síntomas cutáneos desaparecieron a los 10 días de la resección tumoral. Se concluye que los cambios histológicos observados pueden ser claves en la búsqueda de una enfermedad distante de la piel y permiten hacer su diagnóstico. El patrón histológico de vacuolización y necrosis epidérmica subcórnea debe llevar a sospechar la presencia de un glucagonoma pancreático.

Necrolytic migratory erythema is a rare paraneoplastic dermatosis that may be the first clinical manifestation of the glucagonoma syndrome, a disorder characterized by mucocutaneous rash, glucose intolerance, hypoaminoacidemia, hyperglucagonaemia and pancreatic glucagonoma. The clinical case of a 45-year-old woman is presented. She had been experiencing weight loss, polydipsia, polyphagia, postprandial emesis, excessive hair loss and abdominal pain for two months. Erythematous, scaly and migratory plaques with 20 days of evolution were found on her trunk, perineum, elbows, hands, feet, inframammary and antecubital folds. The skin biopsy revealed noticeable vacuolar changes in high epidermal cells, extensive necrosis and thin orthokeratotic cornified layer. These findings pointed to a diagnosis of necrolytic migratory erythema. A suggestion was made to investigate a pancreatic glucagonoma. Laboratory tests showed moderate anemia, hyperglycemia and marked hyperglucagonaemia. Abdominal ultrasound revealed a mass in the tail of the pancreas measuring 6 x 5 x 5 cm which was resected. The histopathological findings were compatible with a diagnosis of glucagonoma, as confirmed by immunohistochemistry. Skin symptoms disappeared 10 days after the tumor resection. We can conclude that the histological changes defined may be clues that can lead the search for a distant skin disease and allow for its diagnosis. The histological pattern of vacuolation and epidermal necrosis should arouse suspicion of pancreatic glucagonoma.