Importance: Facial lipoatrophy is a common problem among the Human Immunodeficiency Virus (HIV) population. With highly active antiretroviral therapy, these patients are able to delay the evolution of the disease and ...Importance: Facial lipoatrophy is a common problem among the Human Immunodeficiency Virus (HIV) population. With highly active antiretroviral therapy, these patients are able to delay the evolution of the disease and live many more years;however, more than half of them are faced with difficulties in their social and professional lives secondary to the physical changes of their faces. Observations: The majority of HIV-positive patients exhibit significant facial soft tissue loss, especially in the buccal fat pad resulting in accentuation of the malar eminence and the inferior orbital rim. Reconstruction has been performed with many temporary and permanent methods, but no single satisfactory procedure has been universally adopted. Conclusions and Relevance: We present a new method of addressing the resulting facial hollowing by tailoring a multi-layered e-PTFE sheet in a customized fashion to camouflage the specific atrophic areas in the face. Our patient demonstrated a significant improvement in both cosmesis and social re-integration. A detailed surgical description along with a review of the literature is reported.展开更多
In this work, the polytetrafluoroethylene (PTFE)-based composite substrates were manufactured by mixing, calendering, hot-pressing sintering. The composition of all the samples was PTFE, SiO2 and chopped E-glass fiber...In this work, the polytetrafluoroethylene (PTFE)-based composite substrates were manufactured by mixing, calendering, hot-pressing sintering. The composition of all the samples was PTFE, SiO2 and chopped E-glass fibers. The effects of content of E-glass fibers on the properties of the SiO2 filled PTFE composites were investigated, including density, water absorption, dielectric properties (εr, tanδ), coefficient of thermal expansion (CTE) and temperature coefficient of dielectric constant (τε). The compositions of inorganic materials mixture are (62 ? x) % SiO2 + x % E-glass fiber (x: mass ratio to composites, x = 0, 1, 1.5, 2, 2.5, 3). The results show that as the content of E-glass fibers is 2.5 wt.%, this composite obtains optimal properties, including excellent dielectric properties (εr^2.9123, tanδ~0.0011), acceptable water absorption of 0.075%, temperature coefficient of dielectric constant of 10 ppm/?C and coefficient of thermal expansion of 15.87 ppm/?C.展开更多
以E玻璃纤维平纹织物作为增强材料、聚四氟乙烯(PTFE)作为基体,通过溶液浸渍法工艺制备预浸料。然后,预浸料经烘干、冷压、烧结得到单层E玻璃纤维/聚四氟乙烯复合材料。在此基础上,通过模压法和环氧树脂黏结形成E玻璃纤维/聚四氟乙烯/...以E玻璃纤维平纹织物作为增强材料、聚四氟乙烯(PTFE)作为基体,通过溶液浸渍法工艺制备预浸料。然后,预浸料经烘干、冷压、烧结得到单层E玻璃纤维/聚四氟乙烯复合材料。在此基础上,通过模压法和环氧树脂黏结形成E玻璃纤维/聚四氟乙烯/环氧树脂基透波复合材料。最后,对透波复合材料进行SEM观察及介电性能和屏蔽效能测试。结果表明,透波复合材料界面结合良好,其介电常数为3.5504,介电损耗角正切为0.004 40,屏蔽效能平均值为0.084 d B,传输系数为0.990,能满足高性能透波复合材料的要求。展开更多
文摘Importance: Facial lipoatrophy is a common problem among the Human Immunodeficiency Virus (HIV) population. With highly active antiretroviral therapy, these patients are able to delay the evolution of the disease and live many more years;however, more than half of them are faced with difficulties in their social and professional lives secondary to the physical changes of their faces. Observations: The majority of HIV-positive patients exhibit significant facial soft tissue loss, especially in the buccal fat pad resulting in accentuation of the malar eminence and the inferior orbital rim. Reconstruction has been performed with many temporary and permanent methods, but no single satisfactory procedure has been universally adopted. Conclusions and Relevance: We present a new method of addressing the resulting facial hollowing by tailoring a multi-layered e-PTFE sheet in a customized fashion to camouflage the specific atrophic areas in the face. Our patient demonstrated a significant improvement in both cosmesis and social re-integration. A detailed surgical description along with a review of the literature is reported.
文摘In this work, the polytetrafluoroethylene (PTFE)-based composite substrates were manufactured by mixing, calendering, hot-pressing sintering. The composition of all the samples was PTFE, SiO2 and chopped E-glass fibers. The effects of content of E-glass fibers on the properties of the SiO2 filled PTFE composites were investigated, including density, water absorption, dielectric properties (εr, tanδ), coefficient of thermal expansion (CTE) and temperature coefficient of dielectric constant (τε). The compositions of inorganic materials mixture are (62 ? x) % SiO2 + x % E-glass fiber (x: mass ratio to composites, x = 0, 1, 1.5, 2, 2.5, 3). The results show that as the content of E-glass fibers is 2.5 wt.%, this composite obtains optimal properties, including excellent dielectric properties (εr^2.9123, tanδ~0.0011), acceptable water absorption of 0.075%, temperature coefficient of dielectric constant of 10 ppm/?C and coefficient of thermal expansion of 15.87 ppm/?C.
文摘以E玻璃纤维平纹织物作为增强材料、聚四氟乙烯(PTFE)作为基体,通过溶液浸渍法工艺制备预浸料。然后,预浸料经烘干、冷压、烧结得到单层E玻璃纤维/聚四氟乙烯复合材料。在此基础上,通过模压法和环氧树脂黏结形成E玻璃纤维/聚四氟乙烯/环氧树脂基透波复合材料。最后,对透波复合材料进行SEM观察及介电性能和屏蔽效能测试。结果表明,透波复合材料界面结合良好,其介电常数为3.5504,介电损耗角正切为0.004 40,屏蔽效能平均值为0.084 d B,传输系数为0.990,能满足高性能透波复合材料的要求。
