By exploiting the extremely large effective cross sections (10 217 10 216 cm 2 ͞molecule) available from surface-enhanced Raman scattering (SERS), we achieved the first observation of single molecule Raman scattering. Measured spectra of a single crystal violet molecule in aqueous colloidal silver solution using one second collection time and about 2 3 10 5 W͞cm 2 nonresonant near-infrared excitation show a clear "fingerprint" of its Raman features between 700 and 1700 cm 21. Spectra observed in a time sequence for an average of 0.6 dye molecule in the probed volume exhibited the expected Poisson distribution for actually measuring 0, 1, 2, or 3 molecules.

3D surface matching is fundamental for shape registration, deformable 3D non-rigid tracking, recognition and classification. In this paper we describe a novel approach for generating an efficient and optimal combined matching from multiple boundary-constrained conformal parameterizations for multiply connected domains (i.e., genus zero open surface with multiple boundaries), which always come from imperfect 3D data acquisition (holes, partial occlusions, change of pose and nonrigid deformation between scans). This optimality criterion is also used to assess how consistent each boundary is, and thus decide to enforce or relax boundary constraints across the two surfaces to be matched. The linear boundary-constrained conformal parameterization is based on the holomorphic differential forms, which map a surface with n boundaries conformally to a planar rectangle with (n − 2) horizontal slits, other two boundaries as constraints. The mapping is a diffeomorphism and intrinsic to the geometry, handles an open surface with arbitrary number of boundaries, and can be implemented as a linear system. Experimental results are given for real facial surface matching, deformable cloth nonrigid tracking, which demonstrate the efficiency of our method, especially for 3D non-rigid surfaces with significantly inconsistent boundaries.

Using standard and internationally validated methods, 86 anthropologic characteristics were determined in 650 male (305 from urban areas and 345 from rural areas) and 704 female (331 from urban areas, 373 from rural areas) Chinese Hakka adults living in Guangdong and Jiangxi. The data were used to calculate 24 anthropologic indices, which were analyzed statistically. The physical characteristics of Hakka subjects were analyzed and compared with reference ethnic data. There were four main findings of this study. First, a small proportion of Hakka adults had an eye fold on the upper eyelid, but a large proportion had a mongoloid fold. The eye slits were narrow in most adults, had a medium nasal root height and straight bridges, and most of the external angles were prominent. The nasal base was upturned in most men. The distributions of the three types of nasal base in women were similar. The proportions of subjects with middle and high alae nasi heights were high and similar. Males with a maximum nostril diameter were mostly classified as transverse and oblique, while many women were classified as transverse and had relatively wide alae nasi. The round lobe type was the most common. Upper lip skin height was mostly classified as medium. Lips were classified as thin. The hair was black, eyes were brown, and the skin was yellowish. Second, the head length was long in male Hakka. The minimum frontal breadth, face breadth, lip height, and interocular breadth were similar to those of North-Asian populations. Meanwhile, head breadth, morphological facial height, nose breadth, mouth breadth, and nose height were similar to those of South-Asian populations. Head length was long in female Hakka. The minimum frontal breadth, face breadth, lip height, and interocular breadth were similar to those of North-Asian populations. Head breadth, nose breadth, and mouth breadth were similar to those of South-Asian populations. Third, the stature of male and female Hakka in urban and rural areas was classified as medium. The proportions of male and female Hakka classified as mesocephaly (length-breadth index of the head), hypsicephalic type, metriocephalic type (breadth-height index of the head) mesorrhiny, long trunk, subbrachyskelic type, broad shoulder breadth, and narrow distance between iliac crests were higher than those of other types. Finally, principal component analyses showed that the physical characteristics of Hakka were between those of South-Asian and North-Asian ethnic populations, but were generally closer to those of North-Asian populations in China. somatoscopy, ethnicity,

Order-N methods for calculating the electronic structure of clusters containing hundreds of atoms using realistic self-consistent density-functional theory local-density approximation potentials make it possible to test alloy theories more definitively. Tests are carried out on isomorphous models of alloys in which the atoms of each species are treated as identical. In contrast, the order-N calculations lead to a polymorphous model in which all of the atoms are unique. Isomorphous models are seen to reproduce average densities of states and cohesive energies surprisingly well, in spite of their deficiencies in other areas.