Immobilization of invertase in conducting polymer matrices

Cataloged from PDF version of article.This paper reports a novel approach in the electrode immobilization of an enzyme, invertase, by electrochemical polymerization of pyrrole in the presence of enzyme. The polypyrrolelinvertase and polyamide/polypyrrole/invertase electrodes were constructed by the entrapment of enzyme in conducting matrices during electrochemical polymerization of pyrrole. This study involves the preparation and characterization of polypyrrole/invertase and polyamidelpolypyrrolelinvertase electrodes under conditions compatible with the enzyme. It demonstrates the effects of pH and temperature on the properties of enzyme electrode. Enzyme leakage tests were carried out during reuse number studies. The preparation of enzyme electrodes was done in two different electrolyte/ solvent systems. The enzyme serves as a sucrose electrode and retains its activity for several months. (c) 1997 Elsevier Science Limited. All rights reserve

Primary extranodal Non-Hodgkin`s lymphoma presenting as painful gingval swelling

Primary extra-nodal non-Hodgkin’s lymphomas (NHL) constitute 25–40% of NHL but less than 1% arises in oral cavity. Here in 53-year-old man with stage IE gingival diffuse large B cell lymphoma who was treated successfully with chemotherapy and radiotherapy was presented

Breast cancer with diabetes insipidus

Diabetes insipidus (DI) is a rare clinical condition, which is usually caused by neurohypophyseal or pituitary stalk infiltration in cancer patients. Case report: we present a 62-year old metastatic breast cancer woman with DI. She admitted to the hospital because of nausea, vomiting, polyuria and polydipsia, while she was on no cytotoxic medication. She had no electrolyte imbalance except mild hypernatremia. The CT scan of the brain yielded a suspicious area in pituitary gland. A pituitary stalk metastasis was found on magnetic resonance imaging (MRI) of pituitary. Water deprivation test was compatible with DI. A clinical response to nasal vasopressin was achieved. Conclusions: Cancer patients who have symptoms such as nausea, vomiting, polyuria and polydipsia while they are not on chemotherapy should be evaluated for not only metabolic complications like hypercalcemia but also posterior pituitary or stalk metastasis MRI could be the choice of imaging for pituitary metastasis.Несахарный диабет (DI) — редкое клиническое состояние, вызываемое инфильтрацией нейрогипофизарной ножки или ножки гипофиза у онкологических больных. Описание случая: в исследовании рассмотрен случай выявления DI у 62-летней женщины, у которой был выявлен рак молочной железы с наличием метастазов. Она поступила в больницу с симптомами тошноты, рвоты, полиурии и полидипсии, хотя не проходила курса химиотерапии. У больной не выявлено дисбаланса электролитов, кроме небольшой гипернатриемии. Компьютерная томография мозга показала подозрительную область в мозговом придатке. На магнитно-резонансном изображении выявлен метастаз в ножке гипофиза. Обезвоживание также соответствовало диагнозу DI. Получен клинический ответ на назальный вазопрессин. Выводы: онкологические больные с симптомами тошноты, рвоты, полиурии и полидипсии, не проходящие курса химиотерапии, должны быть обследованы не только на предмет метаболических осложнений, таких как гиперкальциемия, но и на возможное наличие метастазов в ножке и задней части гипофиза с помощью магнитно-резонансного изображения. Ключевые слова: рак, несахарный диабет, метастаз в гипофизе

Benchmarking of Different Powder-Bed Metal Fusion Processes for Machine Selection in Additive Manufacturing

In the last decade, additive manufacturing has gained significant interest for direct part production and started to change the way companies manufacture products; even in very demanding sectors like aerospace. The biggest challenge for a wider industrial acceptance still stands as the need for more reliable, repeatable and precise machines for additive manufacturing. This paper presents a comprehensive benchmarking study for the selection of an additive manufacturing machine for powder-bed metal fusion process, i.e. Selective Laser Melting or Direct Metal Laser Sintering or Laser Cusing. Four different machine vendors for the same technology to be employed for aeroengine part manufacturing using Inconel 625 powder have been involved for comparing different machine specifications. Many aspects such as dimensional accuracy, surface quality, need of support structures, density, hardness and process limits (minimum wall thickness, overhang surfaces, inclinations and curvatures, etc.) are addressed in the paper. The state-of-the-art in machines for powder-bed metal fusion process is presented aiming at understanding the current limitations of the technology available today.Mechanical Engineerin

A CONDUCTING COMPOSITE OF POLYPYRROLE .1. SYNTHESIS AND CHARACTERIZATION

A conducting composite of polypyrrole was prepared via electrochemical methods. A polyamide was used as the insulating matrix polymer. The characterization of the composite was done by FT-IR, SEM, TGA, DSC and pyrolysis studies. Conductivity and solubility studies together with spectroscopic methods reveal that H bonding exists between the two polymers and a possible grafting to a certain extent

Parabolic oblique derivative problem in generalized Morrey spaces

We study the regularity of the solutions of the oblique derivative problem for linear uniformly parabolic equations with VMO coefficients. We show that if the right-hand side of the parabolic equation belongs to certain generalized Morrey space than the strong solution belongs to the corresponding generalized Sobolev-Morrey space