Effective Circle Count for Apollonian packings and Closed horospheres

The main result of this paper is an effective count for Apollonian circle packings that are either bounded or contain two parallel lines. We obtain this by proving an effective equidistribution of closed horospheres in the unit tangent bundle of a geometrically finite hyperbolic 3-manifold of infinite volume, whose fundamental group has critical exponent bigger than 1. We also discuss applications to Affine sieves. Analogous results for surfaces are treated as well.Comment: 43 pages, 2 figures, To appear in GAF

Effect of Zr content on phase stability, deformation behavior, and Young's modulus in Ti-Nb-Zr alloys

Ti alloys have attracted continuing research attention as promising biomaterials due to their superior corrosion resistance and biocompatibility and excellent mechanical properties. Metastable beta-type Ti alloys also provide several unique properties such as low Young's modulus, shape memory effect, and superelasticity. Such unique properties are predominantly attributed to the phase stability and reversible martensitic transformation. In this study, the effects of the Nb and Zr contents on phase constitution, transformation temperature, deformation behavior, and Young's modulus were investigated. Ti-Nb and Ti-Nb-Zr alloys over a wide composition range, i.e., Ti-(18-40)Nb, Ti-(15-40)Nb-4Zr, Ti-(16-40)Nb-8Zr, Ti-(15-40)Nb-12Zr, Ti-(12-17)Nb-18Zr, were fabricated and their properties were characterized. The phase boundary between the beta phase and the alpha '' martensite phase was clarified. The lower limit content of Nb to suppress the martensitic transformation and to obtain a single beta phase at room temperature decreased with increasing Zr content. The Ti-25Nb, Ti-22Nb-4Zr, Ti-19Nb-8Zr, Ti-17Nb-12Zr and Ti-14Nb-18Zr alloys exhibit the lowest Young's modulus among Ti-Nb-Zr alloys with Zr content of 0, 4, 8, 12, and 18 at.%, respectively. Particularly, the Ti-14Nb-18Zr alloy exhibits a very low Young's modulus less than 40 GPa. Correlation among alloy composition, phase stability, and Young's modulus was discussed.Web of Science132art. no. 47

Labor utilization of migrants in urban Korea, 1970

The purpose of this paper is to examine the labor force characteristics of urban migrants in relation to industrial structure in Korea in 1970. In the 1960s Korea experienced a very rapid urban growth. Urban population increased from 28 percent of the total population in 1960 to 41 percent of the total population in 1970. The annual growth of the urban population was almost three times that of the country as a whole (IPP, 1972 :78). Migration played an important role in this rapid urban growth. Net migration accounted for 49 percent of the urban population increase between 1960 and 1966 and for 73 percent of the urban population increase between 1966 and 1970 (Kwon et. al., 1975: 75-76). The rapid growth of urban population was accompanied by a rapid growth of the secondary industries. Among workers between the ages of 14 to 64, the proportion of employment in secondary industries increased from 8.9 to 19.1 percent for the nation as a whole and from 23.5 to 36.6 percent for the urban areas (Min, 1982: 165-169)

Role of Pikfyve in Platelet Lysosomal Homeostasis

PIKfyve is a lipid kinase that is essential for the synthesis of phosphatidylinositol-3,5-bisphosphate [PtdIns(3,5)P2], and for the regulation of membrane dynamics within the endolysosomal system in mammals. Depletion of intracellular pools of PtdIns(3,5)P2 in humans and in mice is associated with neurodegeneration and early lethality. However, the biological role of PtdIns(3,5)P2 in non-neural tissues is not well understood. Platelets are hematopoietic cells that function in a variety of physiological responses. Essential to many of these functions is the activation-dependent release of effectors from distinct storage granules - alpha granules, dense granules, and lysosomes - that derive from the endolysosomal system. In this work, we show that platelet-specific ablation of the PIKfyve gene in mice results in accelerated arterial thrombosis, but also unexpectedly to multiorgan defects that impair development, body mass, fertility, and survival by inducing inappropriate inflammatory responses characterized by macrophage accumulation in multiple tissues. Platelet depletion in vivo significantly impairs the progression of multiorgan defects in these mice, confirming that these defects reflect a platelet-specific process. Although PIKfyve-null platelets generate and release normal amounts of alpha granule and dense granule contents, they develop defective maturation and excessive storage of lysosomal enzymes, which are released upon platelet activation. Remarkably, impairing the secretion of lysosomes from PIKfyve-deficient platelets in vivo significantly attenuates the multiorgan defects in mice, suggesting that platelet lysosome secretion contributes to pathogenesis. Together, these results demonstrate that PIKfyve is an essential regulator for the biogenesis of platelet lysosomes, and highlight the previously unrecognized and important pathological contributions of platelet lysosomes in inflammation, arterial thrombosis, and macrophage biology

Difference in Organizational Resources Across Neighborhoods for Community-Dwelling Older Adults with Deteriorating Physical and Cognitive Health

Special Studies Experience, Summer 2016 -- Seoul, Korea -- Partner Agencie(s): The Joint World Conference on Social Work, Education and Social Development (SWSD) 2016http://deepblue.lib.umich.edu/bitstream/2027.42/134339/1/Poster_Kim_Minhee-SWSD2016.pd