Исследование гидродинамики и теплообмена при неизотермическом течении углеводородной вязкой среды в трубопроводе, проложенном в районе многолетнемерзлых грунтов

В процессе исследования проводились расчеты изменений полей скорости, распределений температуры по длине трубопровода; зависимости теплового пограничного слоя от длины трубопровода. Анализировались процессы конвективного теплообмена в условиях развивающегося потока и формирования теплового и динамического пограничных слоев по длине. В результате исследования был произведен сравнительный анализ интегро-дифференциальных и точных методов моделирования динамики и теплообмена при течении углеводородных сред в трубопроводах на начальных участках в режимах вязкостно-инерционного ламинарного и турбулентного течения и теплообмена.In the course of the study, calculations were made of changes in the velocity fields and temperature distributions along the pipeline; the dependence of the thermal boundary layer on the length of the pipeline. The processes of convective heat transfer under the conditions of the developing flow and the formation of thermal and dynamic boundary layers along the length were analyzed. The study resulted in a comparative analysis of integro-differential and accurate methods for modelling the dynamics and heat transfer during the flow of hydrocarbon media in pipelines in the initial sections in the modes of viscous-inertial laminar and turbulent flow and heat transfer

Influence of lip closure on alveolar cleft width in patients with cleft lip and palate

<p>Abstract</p> <p>Background</p> <p>The influence of surgery on growth and stability after treatment in patients with cleft lip and palate are topics still under discussion. The aim of the present study was to investigate the influence of early lip closure on the width of the alveolar cleft using dental casts.</p> <p>Methods</p> <p>A total of 44 clefts were investigated using plaster casts, 30 unilateral and 7 bilateral clefts. All infants received a passive molding plate a few days after birth. The age at the time of closure of the lip was 2.1 month in average (range 1-6 months). Plaster casts were obtained at the following stages: shortly after birth, prior to lip closure, prior to soft palate closure. We determined the width of the alveolar cleft before lip closure and prior to soft palate closure measuring the alveolar cleft width from the most lateral point of the premaxilla/anterior segment to the most medial point of the smaller segment.</p> <p>Results</p> <p>After lip closure 15 clefts presented with a width of 0 mm, meaning that the mucosa of the segments was almost touching one another. 19 clefts showed a width of up to 2 mm and 10 clefts were still over 2 mm wide. This means a reduction of 0% in 5 clefts, of 1-50% in 6 clefts, of 51-99% in 19 clefts, and of 100% in 14 clefts.</p> <p>Conclusions</p> <p>Early lip closure reduces alveolar cleft width. In most cases our aim of a remaining cleft width of 2 mm or less can be achieved. These are promising conditions for primary alveolar bone grafting to restore the dental bony arch.</p

A Simple Econometric Approach for Modeling Stress Event Intensities

The authors would like to thank the editor Bob Webb, and the participants of the 2014 Deakin University Conference on the Performance of Financial Markets and Credit Derivatives for helpful and valuable comments. The support by the Centre for International Finance and Regulation (CIFR, project number E001) is gratefully acknowledged. CIFR is funded by the Commonwealth and NSW Governments and supported by other Consortium members (see www.cifr.edu.au)

Reconstruction of Sphenoid Wing Dysplasia with Pulsating Exophthalmos in a Case of Neurofibromatosis Type 1 Supported by Intraoperative Navigation Using a New Skull Reference System

A patient with neurofibromatosis type 1 had pulsating exophthalmos of the right eye with diplopia resulting from severe dysplasia of the sphenoid bone and consecutive herniation of the right temporal lobe. The right orbital tectum was reconstructed with titanium mesh and iliac spongiosa via a lateral orbitotomy using intraoperative navigation. For intraoperative referencing a cortical fixed–reference system and a skin scanning laser device were used. Postoperatively, the diplopia was reduced, but the patient asked for further treatment and the procedure was repeated 6 months later. Intraoperatively, the previously implanted titanium mesh was deformed and most of the transplanted bone was resorbed, probably because of pressure. A more extended mesh was implanted and iliac spongiosa was placed on both sides. Intraoperative navigation was used during both procedures. The adverse effects of diplopia were minimized and follow–up computed tomography after seven months confirmed that the bone graft was in place

Resection of small plexiform neurofibromas in neurofibromatosis type 1 children

Abstract Background Plexiform neurofibromas (PNF) are benign tumors of the peripheral nerve which mostly develop in patients with neurofibromatosis type 1 (NF1). Surgical interventions are usually not applied to children with small tumors. These are rather restricted to debulking of larger tumors in adults that cause clinical complications or aesthetic disfigurement. In most cases, a total resection of PNF is not possible due to the network-like growth of the tumors. Patients and methods Early surgical intervention was carried out for 9 small PNFs in 7 NF1 children. Tumor resection was performed following the graphical delineation of the affected skin and according the MRI findings. Results Total resection was achieved for all 9 PNF without causing any neurological or organic deficit. Annual magnetic resonance tomography over a period of four years did not reveal any relapse of the tumors. Conclusions Early surgical intervention for small superficial PNFs in NF1 children have various advantages and may especially be considered a strategy to prevent progression.</p