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Numerous behavioral observations and brain function studies have demonstrated that neurological differences exist between East Asians and Westerners. However, the extent to which these factors relate to differences in brain structure is still not clear. As the basis of brain functions, the anatomical differences in brain structure play a primary and critical role in the origination of functional and behavior differences. To investigate the underlying differences in brain structure between the two cultural/ethnic groups, we conducted a comparative study on education-matched right-handed young male adults (age = 22-29 years) from two cohorts, Han Chinese (n = 45) and Caucasians (n = 45), using high-dimensional structural magnetic resonance imaging (MRI) data. Using two well-validated imaging analysis techniques, surface-based morphometry (SBM) and voxel-based morphometry (VBM), we performed a comprehensive vertex-wise morphometric analysis of the brain structures between Chinese and Caucasian cohorts. We identified consistent significant between-group differences in cortical thickness, volume, and surface area in the frontal, temporal, parietal, occipital, and insular lobes as well as the cingulate cortices. The SBM analyses revealed that compared with Caucasians, the Chinese population showed larger cortical structures in the temporal and cingulate regions, and smaller structural measures in the frontal and parietal cortices. The VBM data of the same sample was well-aligned with the SBM findings. Our findings systematically revealed comprehensive brain structural differences between young male Chinese and Caucasians, and provided new neuroanatomical insights to the behavioral and functional distinctions in the two cultural/ethnic populations.

electronics include stretchable solar cells, [2] stretchable organic light emitting diodes (OLEDs), [3] stretchable field-effect transistors (FETs), [4] stretchable supercapacitors, [5] stretchable actuators [6] and heaters, [7] etc. The emerging of stretchable electronics has foreseen the revolution of future electronics, ranging from design, shape and functions to installation, applications and even user experience. For example, stretchable optoelectronics, such as solar cells and OLEDs, are conformable, rollable and foldable. They can be installed on irregularly shaped roof or side walls of buildings, vehicles and other public utilities. Similarly, stretchable sensors used as e-skin can not only fit motions at joints of human or robots with tensile strain of large than 100%, [1e] but also sense signals related to strain, temperature, humidity and even blood pressure. [8] Moreover, the integration of different kinds of stretchable electronics may exhibit diversity in functions. [9] For instance, wearable devices of stretchable energy harvesting and storage electronics combining with stretchable sensors and heaters may sense the biomedical signal and keep the patient warm with the power collected from solar/friction energy. More potential applications of stretchable electronics in different fields, not restricted to the above examples, will be seen in the future.Stretchable transparent conductors (STCs) are fundamental components in stretchable electronics. They generally consist of a stretchable transparent polymeric substrate and a layer of conducting elements on or embedded in the substrate. The substrates involve poly(dimethyl siloxane) (PDMS) and polyacrylate-based elastomers [10] while the conducting elements include conducting polymers, [11] metal nanowires, [12] carbon nanotubes (CNTs), [13] graphene [14] or their hybrids. The substrates generally show transmittance of higher than 90% [15] and can be stretched to a strain of larger than 100%, e.g., PDMS and VHB (a typical acrylic elastomer) could exhibit a fracture tensile strain up to ≈160% [16] and several hundred percentages, [6a,17] respectively. STCs could be considered as the combination of transparent conductors and stretchable conductors; [18] they can simultaneously show stable conductivity and transparency upon deformation, including bending, folding, twisting, crumpling, stretching, etc. The transparency of STCs is attributed to the low attenuation of visible light by the substrate and the conducting layer. The conductivity is obtained due to the continuity of conducting layer either via uniform film or the connection of Stretchable transparent conductors (STCs), generally consisting of conducting networks and stretchable transparent elastomers, can maintain stable conductivity and transparency even at large tensile strain, beyond the reach of rigid/flexible transparent conductors. They are essential components in stretchable/wearable electronics for using on irregular 3D conformable surfaces and have attracted tremendous attention ...

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Polycaprolactone (PCL), poly (lactic acid) (PLA) and hydroxyapatite (HA) are frequently used as materials for tissue engineering. In this study, PCL/PLA/HA nanofiber mats with different weight ratio were prepared using electrospinning. Their structure and morphology were studied by FTIR and FESEM. FTIR results demonstrated that the HA particles were successfully incorporated into the PCL/PLA nanofibers. The FESEM images showed that the surface of fibers became coarser with the introduction of HA nanoparticles into PCL/PLA system. Furthermore, the addition of HA led to the decreasing of fiber diameter. The average diameters of PCL/PLA/HA nanofiber were in the range of 300-600 nm, while that of PCL/PLA was 776 +/- 15.4 nm. The effect of nanofiber composition on the osteoblast-like MC3T3-E1 cell adhesion and proliferation were investigated as the preliminary biological evaluation of the scaffold. The MC3T3-E1 cell could be attached actively on all the scaffolds. The MTT assay revealed that PCL/PLA/HA scaffold shows significantly higher cell proliferation than PCL/PLA scaffolds. After 15 days of culture, mineral particles on the surface of the cells was appeared on PCL/PLA/HA nanofibers while normal cell spreading morphology on PCL/PLA nanofibers. These results manifested that electrospun PCL/PLA/HA scaffolds could enhance bone regeneration, showing their marvelous prospect as scaffolds for bone tissue engineering.