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141.
The Special Surveillance Breast Program (SSBP) is a long-term, comprehensive, multidisciplinary program for women determined to be at high risk for the development of breast cancer. Because the women who attend this program are otherwise healthy but concerned about their risk for breast cancer, current and relevant information is required to address their concerns regarding the possibility of developing breast cancer. The purpose of this article is to describe the risk factors that indicate eligibility for the program, the structure of the program, and the results of an assessment that identified the needs of this special population. 相似文献
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143.
Measurements of five variations of a toroidal point-contact dc superconducting quantum interference device (SQUID) are presented. The energy resolution and other parameters of these SQUIDs are examined and compared with the predictions of the Resistively Shunted Junction model. For these SQUIDs, the measured minimum energy resolution was approximately 2×10–30 J/Hz. Excess noise in the point contacts was found to limit the energy resolution of the SQUIDs. A comparison between the typical junction parameters and noise obtained for our niobium-niobium point contacts and those of others is given. TheI–V characteristics of the junctions showed the effects of Joule heating. The white voltage noise spectral density was found to have an approximately parabolic dependence on the average voltage for bias currents larger than the critical current. While this parabolic dependence is consistent with heating effects in the junctions, the amplitude of the noise cannot be explained in terms of a heating model. The low-frequency noise of the point contacts has also been investigated. 相似文献
144.
Ungyu Paik Jeong-Gu YeoMoon-Hwan Lee Vincent A HackleyYeon-Gil Jung 《Materials Research Bulletin》2002,37(9):1623-1631
The electrokinetic behavior of BaTO3 particles in an aqueous medium exhibited a hysteresis loop with titration direction. As BaTiO3 suspension was titrated toward acidic pH, the amount of Ba2+ dissolution strongly increased, and in the subsequent titration toward alkaline pH, Ba2+ adsorbed and/or reprecipitated on the Ba-depleted BaTiO3 surface. This dissolution-reprecipitation cycle results in the observed hysteresis behavior. An attempt was made to identify the responsible species of the adsorbed/reprecipitated compound by XPS in conjunction with electrokinetic titrations. 相似文献
145.
Jeom Kee Paik 《钢结构》2008,23(9):77-77
作为作者系列研究成果[Paik J K.Ultimate strength of perforated steel plates under edge shear loading.Thin-Walled Structures,2007,45:301-6,Paik J K.Ultimate strength of perforated steel plates under axial compressive loading along short edges.Ships Offshore Struct,2007,2(3):(inpress)]的终结篇,与前期论文在边缘剪力或单轴压力荷载方面进行了对比,目的是研究双轴受压和边缘剪力作用下多孔钢板的极限强度特点,这是船舶和船舶型海洋结构在货物和水压作用下的一个典型受力模式。板的约束考虑为四边简支,中心区域为圆形孔。一系列ANSYS非线性有限元分析中考虑了不同的板尺寸(厚度)。在有限元分析基础上,推导出组合荷载下多孔板的极限强度交互关系公式,可用于可靠性分析或规范中极限强度的预测。 相似文献
146.
147.
Jung‐Min Moon Bong‐Soo Kim Hyun‐Jong Paik Jang‐Oo Lee Emiko Mouri Kohji Yoshinaga 《Polymer Engineering and Science》2010,50(6):1067-1074
Silica nanoparticles with well‐defined, highly grafted dense poly(methyl methacrylate) (MMA) were prepared by surface‐initiated activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) of methyl methacrylate with an initiator‐fixed silica particle in the presence of air. Two different polymerizations of MMA were carried out under the same conditions using tris[2‐(dimethylamino)ethyl]amine (Me6TREN) and N,N,N′,N′,N″‐pentamethyldiethylene‐triamine (PMDETA) as the ligand, respectively. In the CuCl2/PMDETA system, polymerization appeared to be more controlled with a lower polydisperisty compared with the CuCl2/Me6TREN system. The monolayer of these particles was formed at the air–water interface using Langmuir‐Blodgett (LB) technique. Multilayers of the particles were fabricated by repetition of LB depositing. A surface pressure–area (π–A) measurement and SEM observation were used to characterize the particle arrays. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers 相似文献
148.
149.
STUDY DESIGN: A case report and literature review of thoracic hyperkyphosis deformity secondary to glucocorticoid-induced osteoporosis in Cushing's disease. OBJECTIVES: To identify the pathophysiology of glucocorticoid-induced osteoporosis and to outline the diagnosis and treatment options for a patient with severe spinal deformity secondary to unrecognized excess glucocorticoid activity. SUMMARY OF BACKGROUND DATA: Glucocorticoid-induced osteoporosis is seen in patients exposed to supraphysiologic levels of endogenous or exogenously administered glucocorticoids. In these patients, glucocorticoids act to suppress bone formation and increase bone resorption by indirect and direct effects. These patients have a high prevalence of trabecular bone loss, resulting in much higher rates of vertebral body collapse and pathologic fracture and thus causing an increased propensity toward kyphotic spinal malalignment. METHODS: The literature was reviewed and case reports studied. This case report highlights the pathophysiology of the disease process that caused the spinal deformity and the surgical intervention used to correct the kyphotic deformity after the metabolic problem was resolved. RESULTS: This patient has responded well to treatment and surgical intervention to correct a thoracic hyperkyphotic deformity without complication. CONCLUSIONS: Unrecognized endogenous production of glucocorticoids in Cushing's disease should be considered in young adult patients with progressive osteoporotic spinal deformities. 相似文献
150.
Hwack Joo Lee Hyun Ryu Hyun Min Park Jong Hoo Paik Sahn Nahm Jae-Dong Byun 《Journal of the American Ceramic Society》1998,81(6):1685-1688
Microstructural studies on the interfacial boundaries of 1:1 and 1:2 ordered domains in (Ba0.9 La0.1 )(Mg0.37 Nb0.63 )O3 were conducted using high-resolution transmission electron microscopy and X-ray diffractometry. Both 1:2 and 1:1 ordered domains coexisted in a fully ordered single grain. Each ordered domain occupied its own region, and the interfaces were atomically sharp and coherent. The wavelength of the superlattice modulation was ∼0.47 nm in the 1:1 ordered domain and ∼0.71 nm in the 1:2 ordered domain. The transition from the 1:2 ordered region to the 1:1 ordered region was clearly shown at the interface. These observations well support the structural models that have been previously presented. 相似文献