Hongsheng Chen

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This paper presents a hardware accelerated approach to the voxelization of a wide range of 3D objects, including curves/surfaces, solids, and geometric and volumetric CSG models. The algorithms generate slices of the object models using a surface graphics processor to form the nal volume representations. Boolean operations in a volumetric CSG model are(More)
Waardenburg syndrome (WS) is a rare disorder characterized by distinctive facial features, pigment disturbances, and sensorineural deafness. There are four WS subtypes. WS1 is mostly caused by PAX3 mutations, while MITF, SNAI2, and SOX10 mutations are associated with WS2. More than 100 different disease-causing mutations have been reported in many ethnic(More)
A cloak that can hide living creatures from sight is a common feature of mythology but still remains unrealized as a practical device. To preserve the wave phase, the previous cloaking solution proposed by Pendry and colleagues required transformation of the electromagnetic space around the hidden object in such a way that the rays bending around the object(More)
A waveguide-based retrieval method for measuring complex permittivity and permeability tensors of metamaterials is presented. In the proposed scheme, multiple independent sets of scattering data for the material under test with different orientations are measured in the frequency range corresponding to the dominant TE(10) mode. The method is applied to(More)
In target tracking sensor networks, tracking quality and network lifetime are two conflicting optimization goals due to the limited battery power of the sensor nodes. During the movement of a target, how to select an optimal subset of sensors to wake up is of critical importance both for extending network lifetime and guaranteeing tracking quality. In this(More)
In nature, the beetle Chrysina gloriosa derives its iridescence by selectively reflecting left-handed circularly polarized light only. Here, an optical analogue is suggested based on an ultrathin metamaterial, which is termed circular dichroism metamirror. A general method to design the circular dichroism metasmirror is presented under the framework of(More)
The identification of cancer stem cells (CSCs) has improved the understanding of tumor occurrence and development. According to CSC theory, colorectal carcinoma (CRC) may be derived from these few cells. Thus, markers for CSCs may lead to the identification of CSCs and investigation of the correlation with various clinicopathological features and survival(More)
Beta-carboline alkaloids such as harmine are present in medicinal plants such as Peganum harmala that have been used as folk medicine in anticancer therapy. In our study, 9 harmine derivatives (including harmine) were investigated for their antitumor effects and acute toxicities in mice, and the structure-activity relationship (SAR) was also analyzed.(More)
The beta-carboline alkaloids have been characterized as a group of potential antitumor agents. The underlying mechanisms of harmine and its derivatives were investigated by DNA binding assay and Topoisomerase (Topo) inhibition assay. Meanwhile, the DNA photocleavage potential of these compounds and their cytotoxicity were also examined by DNA photocleavage(More)
We demonstrate that by utilizing displacement currents in simple dielectric resonators instead of conduction currents in metallic split-ring resonators and by additionally exciting the proper modes, left-handed properties can be observed in an array of high dielectric resonators. Theoretical analysis and experimental measurements show that the modes, as(More)