360 research outputs found

    BIOMECHANICAL CHARACTERISTICS OF THE LOWER EXTREMITY FROM GAIT INTIATION TO THE STEADY-STATE WALKING

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    In this study, biomechanical characteristics during the whole process of gait initiation for twenty healthy volunteers were determined by the three dimension motion analysis. Gait initiation, a transitional movement phenomenon from quiet stance to steady-state walking, involves a series of muscular activities, GRFs, movements of COP and COM and joint motions. Results showed that the location of the net COP to be most lateral during double limb stance at the beginning of gait initiation. During gait initiation, changes in anteroposterior components of GRFs were first found and then changes in vertical components followed. Hip and knee motions were found before the ankle joint motion. Walking speed, step length and stride length gradually increased until the second step. The interaction between the COM and COP is tightly regulated to control the trajectory of the COM and thereby control total body balance

    Electric generator embedded in cellular phone for self-recharge

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    Nowadays, due to the development of information industry and technologies, the objective of cellular phone is not only to communicate, but also to give people various functions such as e-banking, web surfing and even excitement and fun. Because of increased usage of the cellular phone, the available time of the phone rechargeable battery is getting shorter. Therefore, in order to extend the serviceable time of the rechargeable battery, we propose self-generation system using a tubular type of permanent magnet linear self-generator (TPMLG) which can be embedded in cellular phone. The vibrational model is studied utilizing the mechanical resonance and the magnetic circuit such as permanent magnet, steel yoke and coil is designed to improve electricity generation. To investigate the electric characteristics of designed generation system, the transient finite element analysis using commercial software “MAXWELL” is performed

    Computational investigation of epithelial cell dynamic phenotype in vitro

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    <p>Abstract</p> <p>Background</p> <p>When grown in three-dimensional (3D) cultures, epithelial cells typically form cystic organoids that recapitulate cardinal features of in vivo epithelial structures. Characterizing essential cell actions and their roles, which constitute the system's dynamic phenotype, is critical to gaining deeper insight into the cystogenesis phenomena.</p> <p>Methods</p> <p>Starting with an earlier in silico epithelial analogue (ISEA1) that validated for several Madin-Darby canine kidney (MDCK) epithelial cell culture attributes, we built a revised analogue (ISEA2) to increase overlap between analogue and cell culture traits. Both analogues used agent-based, discrete event methods. A set of axioms determined ISEA behaviors; together, they specified the analogue's operating principles. A new experimentation framework enabled tracking relative axiom use and roles during simulated cystogenesis along with establishment of the consequences of their disruption.</p> <p>Results</p> <p>ISEA2 consistently produced convex cystic structures in a simulated embedded culture. Axiom use measures provided detailed descriptions of the analogue's dynamic phenotype. Dysregulating key cell death and division axioms led to disorganized structures. Adhering to either axiom less than 80% of the time caused ISEA1 to form easily identified morphological changes. ISEA2 was more robust to identical dysregulation. Both dysregulated analogues exhibited characteristics that resembled those associated with an in vitro model of early glandular epithelial cancer.</p> <p>Conclusion</p> <p>We documented the causal chains of events, and their relative roles, responsible for simulated cystogenesis. The results stand as an early hypothesis–a theory–of how individual MDCK cell actions give rise to consistently roundish, cystic organoids.</p

    A computational approach to resolve cell level contributions to early glandular epithelial cancer progression

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    <p>Abstract</p> <p>Background</p> <p>Three-dimensional (3D) embedded cell cultures provide an appropriate physiological environment to reconstruct features of early glandular epithelial cancer. Although these are orders of magnitude simpler than tissues, they too are complex systems that have proven challenging to understand. We used agent-based, discrete event simulation modeling methods to build working hypotheses of mechanisms of epithelial 3D culture phenotype and early cancer progression. Starting with an earlier software analogue, we validated an improved in silico epithelial analogue (ISEA) for cardinal features of a normally developed MDCK cyst. A set of axiomatic operating principles defined simulated cell actions. We explored selective disruption of individual simulated cell actions. New framework features enabled recording detailed measures of ISEA cell activities and morphology.</p> <p>Results</p> <p>Enabled by a small set of cell operating principles, ISEA cells multiplied and self-organized into cyst-like structures that mimicked those of MDCK cells in a 3D embedded cell culture. Selective disruption of "anoikis" or directional cell division caused the ISEA to develop phenotypic features resembling those of in vitro tumor reconstruction models and cancerous tissues in vivo. Disrupting either process, or both, altered cell activity patterns that resulted in morphologically similar outcomes. Increased disruption led to a prolonged presence of intraluminal cells.</p> <p>Conclusions</p> <p>ISEA mechanisms, behaviors, and morphological properties may have biological counterparts. To the extent that in silico-to-in vitro mappings are valid, the results suggest plausible, additional mechanisms of in vitro cancer reconstruction or reversion, and raise potentially significant implications for early cancer diagnosis based on histology. Further ISEA development and use are expected to provide a viable platform to complement in vitro methods for unraveling the mechanistic basis of epithelial morphogenesis and cancer progression.</p

    LANIT: Language-Driven Image-to-Image Translation for Unlabeled Data

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    Existing techniques for image-to-image translation commonly have suffered from two critical problems: heavy reliance on per-sample domain annotation and/or inability of handling multiple attributes per image. Recent truly-unsupervised methods adopt clustering approaches to easily provide per-sample one-hot domain labels. However, they cannot account for the real-world setting: one sample may have multiple attributes. In addition, the semantics of the clusters are not easily coupled to the human understanding. To overcome these, we present a LANguage-driven Image-to-image Translation model, dubbed LANIT. We leverage easy-to-obtain candidate attributes given in texts for a dataset: the similarity between images and attributes indicates per-sample domain labels. This formulation naturally enables multi-hot label so that users can specify the target domain with a set of attributes in language. To account for the case that the initial prompts are inaccurate, we also present prompt learning. We further present domain regularization loss that enforces translated images be mapped to the corresponding domain. Experiments on several standard benchmarks demonstrate that LANIT achieves comparable or superior performance to existing models.Comment: Accepted to CVPR 2023. Project Page: https://ku-cvlab.github.io/LANIT

    Temperature measurements of heated microcantilevers using scanning thermoreflectance microscopy

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    We report the development of scanning thermoreflectance thermometry and its application for steady and dynamic temperature measurement of a heated microcantilever. The local thermoreflectance signal of the heated microcantilever was calibrated to temperature while the cantilever was under steady and periodic heating operation. The temperature resolution of our approach is 0.6 K, and the spatial resolution is 2 ÎĽm, which are comparable to micro-Raman thermometry. However, the temporal resolution of our approach is about 10 ÎĽsec, which is significantly faster than micro-Raman thermometry. When the heated microcantilever is periodically heated with frequency up to 100 kHz, we can measure both the in-phase and out-of-phase components of the temperature oscillation. For increasing heating frequency, the measured cantilever AC temperature distribution tends to be confined in the vicinity of the heater region and becomes increasingly out of phase with the driving signal. These results compare well with finite element simulations

    Oldenlandia diffusa Promotes Antiproliferative and Apoptotic Effects in a Rat Hepatocellular Carcinoma with Liver Cirrhosis

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    Oldenlandia diffusa (OD) is commonly used with various diseases such as cancer, arthritis, and autoimmune disease. Liver cirrhosis is a predominant risk factor for hepatocellular carcinoma (HCC). Here, we show that the therapeutic effect of OD, which was investigated both in vitro and chemically, induced HCC model. OD significantly enhanced apoptosis and antiproliferative activity and reduced migration ability of HCC cells. In vivo, OD was treated twice a day for 28 days after confirmed HCC model through 2-[(18)F]-fluoro-2-deoxy-D-glucose ((18)F-FDG) imaging. The survival in OD treated groups was shown to have a greater therapeutic effect than the control group. 28 days after OD treatment, OD treated groups resulted in a significant reduction in tumor number, size, (18)F-FDG uptake, and serum levels such as alanine transaminase, aspartate transaminase, and alkaline phosphate compared to the control group. Also, proliferated cells in tumor sites by OD were reduced compared to the control group. Furthermore, several rats in OD treated group survived over 60 days and liver morphology of these rats showed the difference between tumor mass and normal tissue. These results suggest that OD may have antiproliferative activity, inhibition of metastasis, and apoptotic effects in chemically induced HCC model and can have the potential use for clinical application as anticancer drug of the herbal extract
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