335 research outputs found
Implementasi Kinect Body Tracking pada Sistem Pemindai Biometrik
Biometrik merupakan salah satu identifikasi karakteristik fisiologis seseorang. Tinggi dan berat badan dapat digunakan untuk pengukuran biometrik. Kedua variabel tersebut dapat dikumulasikan untuk mengidentifikasi BMI (Body Mass Index) seseorang. Citra objek yang telah berhasil dicapture oleh Kinect terdiri dari depth image serta titik-titik joint. Depth image dari sebuah citra akan diekstraksi sehingga dihasilkan citra berupa gambar latar belakang (background) dengan warna hitam putih dan titiktitik joint objek akan terlihat dan bisa diproses untuk perhitungan tinggi. Depth sensor akan memetakan objek yang ditangkapnya berdasarkan jarak yang telah ditentukan. Gambar tersebut akan dibandingkan dengan data hasil training sebelumnya. Sensor Kinect diposisikan di depan objek yang diatur dengan jarak 180 cm. Untuk memastikan jarak sensor Kinect tidak berubah, maka sensor ultrasonik diletakkan di depan sensor Kinect agar sistem dapat menyesuaikan posisinya tidak kurang atau lebih dari jarak yang telah ditentukan. Pada pengukuran tersebut diperoleh data tinggi yang dapat diinputkan bersamaan dengan berat badan objek sehingga dapat dihitung BMI seseorang. Setelah dilakukan 8 kali pengujian pada objek dengan tinggi antara 154 – 180 cm diperoleh rata-rata error sebesar 1,35% dari tinggi yang sebenarnya
Inhibitory postsynaptic actions of taurine, GABA and other amino acids on motoneurons of the isolated frog spinal cord
The actions of glycine, GABA, α-alanine, β-alanine and taurine were studied by intracellular recordings from lumbar motoneurons of the isolated spinal cord of the frog. All amino acids tested produced a reduction in the amplitude of postsynaptic potentials, a blockade of the antidromic action potential and an increase of membrane conductance. Furthermore, membrane polarizations occurred, which were always in the same direction as the IPSP. All these effects indicate a postsynaptic inhibitory action of these amino acids. When the relative strength of different amino acids was compared, taurine had the strongest inhibitory potency, followed by β-alanine, α α-alanine, GABA and glycine.
Topically applied strychnine and picrotoxin induced different changes of postsynaptic potentials, indicating that distinct inhibitory systems might be influenced by these two convulsants. Interactions with amino acids showed that picrotoxin selectively diminished the postsynaptic actions of GABA, while strychnine reduced the effects of taurine, glycine, α- and β-alanine. But differences in the susceptibility of these amino acid actions to strychnine could be detected: the action of taurine was more sensitively blocked by strychnine compared with glycine, α- and β-alanine.
With regard to these results the importance of taurine and GABA as transmitters of postsynaptic inhibition on motoneurons in the spinal cord of the frog is discussed
Minimum-weight perfect matching for non-intrinsic distances on the line
Consider a real line equipped with a (not necessarily intrinsic) distance. We
deal with the minimum-weight perfect matching problem for a complete graph
whose points are located on the line and whose edges have weights equal to
distances along the line. This problem is closely related to one-dimensional
Monge-Kantorovich trasnport optimization. The main result of the present note
is a "bottom-up" recursion relation for weights of partial minimum-weight
matchings.Comment: 13 pages, figures in TiKZ, uses xcolor package; introduction and the
concluding section have been expande
A Fisher-Rao Metric for curves using the information in edges
Two curves which are close together in an image are indistinguishable given a measurement, in that there is no compelling reason to associate the measurement with one curve rather than the other. This observation is made quantitative using the parametric version of the Fisher-Rao metric. A probability density function for a measurement conditional on a curve is constructed. The distance between two curves is then defined to be the Fisher-Rao distance between the two conditional pdfs. A tractable approximation to the Fisher-Rao metric is obtained for the case in which the measurements are compound in that they consist of a point x and an angle α which specifies the direction of an edge at x. If the curves are circles or straight lines, then the approximating metric is generalized to take account of inlying and outlying measurements. An estimate is made of the number of measurements required for the accurate location of a circle in the presence of outliers. A Bayesian algorithm for circle detection is defined. The prior density for the algorithm is obtained from the Fisher-Rao metric. The algorithm is tested on images from the CASIA Iris Interval database
The IL-1-Like Cytokine IL-33 Is Constitutively Expressed in the Nucleus of Endothelial Cells and Epithelial Cells In Vivo: A Novel ‘Alarmin’?
BACKGROUND: Interleukin-33 (IL-33) is an IL-1-like cytokine ligand for the IL-1 receptor-related protein ST2, that activates mast cells and Th2 lymphocytes, and induces production of Th2-associated cytokines in vivo. We initially discovered IL-33 as a nuclear factor (NF-HEV) abundantly expressed in high endothelial venules from lymphoid organs, that associates with chromatin and exhibits transcriptional regulatory properties. This suggested that, similarly to IL-1alpha and chromatin-associated cytokine HMGB1, IL-33 may act as both a cytokine and a nuclear factor. Although the activity of recombinant IL-33 has been well characterized, little is known yet about the expression pattern of endogenous IL-33 in vivo. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that IL-33 is constitutively and abundantly expressed in normal human tissues. Using a combination of human tissue microarrays and IL-33 monoclonal and polyclonal antibodies, we found that IL-33 is a novel nuclear marker of the endothelium widely expressed along the vascular tree. We observed abundant nuclear expression of IL-33 in endothelial cells from both large and small blood vessels in most normal human tissues, as well as in human tumors. In addition to endothelium, we also found constitutive nuclear expression of IL-33 in fibroblastic reticular cells of lymphoid tissues, and epithelial cells of tissues exposed to the environment, including skin keratinocytes and epithelial cells of the stomach, tonsillar crypts and salivary glands. CONCLUSIONS/SIGNIFICANCE: Together, our results indicate that, unlike inducible cytokines, IL-33 is constitutively expressed in normal human tissues. In addition, they reveal that endothelial cells and epithelial cells constitute major sources of IL-33 in vivo. Based on these findings, we speculate that IL-33 may function, similarly to the prototype 'alarmin' HMGB1, as an endogenous 'danger' signal to alert the immune system after endothelial or epithelial cell damage during trauma or infection
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