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101.
Creating a virtual city is demanded for computer games, movies, and urban planning, but it takes a lot of time to create numerous 3D building models. Procedural modeling has become popular in recent years to overcome this issue, but creating a grammar to get a desired output is difficult and time consuming even for expert users. In this paper, we present an interactive tool that allows users to automatically generate such a grammar from a single image of a building. The user selects a photograph and highlights the silhouette of the target building as input to our method. Our pipeline automatically generates the building components, from large‐scale building mass to fine‐scale windows and doors geometry. Each stage of our pipeline combines convolutional neural networks (CNNs) and optimization to select and parameterize procedural grammars that reproduce the building elements of the picture. In the first stage, our method jointly estimates camera parameters and building mass shape. Once known, the building mass enables the rectification of the façades, which are given as input to the second stage that recovers the façade layout. This layout allows us to extract individual windows and doors that are subsequently fed to the last stage of the pipeline that selects procedural grammars for windows and doors. Finally, the grammars are combined to generate a complete procedural building as output. We devise a common methodology to make each stage of this pipeline tractable. This methodology consists in simplifying the input image to match the visual appearance of synthetic training data, and in using optimization to refine the parameters estimated by CNNs. We used our method to generate a variety of procedural models of buildings from existing photographs.  相似文献   
102.
Malignant cell contamination in autologous transplants is a potential origin of tumor relapse. Ex vivo expansion of CD34(+) blood progenitor cells (BPC) has been proposed as a tool to eliminate tumor cells from autografts. To characterize the influence of culture conditions on survival, growth, and clonogenicity of malignant cells, we isolated primary mammary carcinoma cells from pleural effusions and ascites of patients with metastatic breast cancer and cultured them in the presence of stem cell factor (SCF), interleukin-1beta (IL-1beta), IL-3, IL-6, and erythropoietin (EPO), ie, conditions previously shown to allow efficient ex vivo expansion of CD34(+) BPC. In the presence of serum, tumor cells proliferated during a 7-day culture period and no significant growth-modulatory effect was attributable to the presence of hematopoietic growth factors. When transforming growth factor-beta1 (TGF-beta1) was added to these cultures, proliferation of breast cancer cells was reduced. Expansion of clonogenic tumor cells was seen in the presence of SCF + IL-1beta + IL-3 + IL-6 + EPO, but was suppressed by TGF-beta1. Cocultures of tumor cells in direct cellular contact with hematopoietic cells showed that tumor cell growth could be stimulated by ex vivo expanded hematopoietic cells at high cell densities (5 x 10(5)/mL). In contrast, culture under serum-free conditions resulted in death of greater than 90% of breast cancer cells within 7 days and a further decrease in tumor cell numbers thereafter. In the serum-free cultures, hematopoietic cytokines and cellular contact with CD34(+) BPC could not protect the tumor cells from death. Therefore, ex vivo expansion of CD34(+) BPC in serum-free medium provides an environment for efficient purging of contaminating mammary carcinoma cells. These results have clinical significance for future protocols in autologous progenitor cell transplantation in cancer patients.  相似文献   
103.
Scanning electrochemical microscopy (SECM) is described using a band microelectrode tip. Numerical calculations allow the determination of approach curves of an insulating or a conductive substrate, and the numerical analysis is compared to experimental curves. Natural convection provides a steady-state current at the band microelectrode at an infinite distance from the substrate, and the band tip may be used in the SECM configuration as easily as the tip of a disk. Owing to the millimetric dimension of the band microelectrode, the substrate has an influence on the current at much longer distances than with the disk. Finally, the advantage of SECM with a band microelectrode is observed with the fast electrochemical modification of a fluoropolymer surface.  相似文献   
104.
Donor lymphocyte infusion (DLI) can (re-)induce durable remission in relapsing patients after allogeneic hematopoietic stem-cell transplantation (alloHSCT). However, DLI harbors the risk of increased non-relapse mortality due to the co-occurrence of graft-versus-host disease (GVHD). GVHD onset may be caused or accompanied by changes in the clonal T-cell receptor (TCR) repertoire. To investigate this, we analyzed T cells in a cohort of 21 patients receiving DLI after alloHSCT. We performed deep T-cell receptor β (TRB) sequencing of sorted CD4+CD25+CD127low regulatory T cells (Treg cells) and CD4+ conventional T cells (Tcon cells) in order to track longitudinal changes in the TCR repertoire. GVHD following DLI was associated with less diverse but clonally expanded CD4+CD25+CD127low Treg and CD4+ Tcon TCR repertoires, while patients without GVHD exhibited healthy-like repertoire properties. Moreover, the diversification of the repertoires upon GVHD treatment was linked to steroid-sensitive GVHD, whereas decreased diversity was observed in steroid-refractory GVHD. Finally, the unbiased sample analysis revealed that the healthy-like attributes of the CD4+CD25+CD127low Treg TCR repertoire were associated with reduced GVHD incidence. In conclusion, CD4+CD25+CD127low Treg and CD4+ Tcon TRB repertoire dynamics may provide a helpful real-time tool to improve the diagnosis and monitoring of treatment in GVHD following DLI.  相似文献   
105.
(1) Interest in the Juncaceae family has risen as some members have shown anti-inflammatory properties and interesting compounds. In this regard, we decided to investigate the antioxidant and anti-inflammatory properties of Luzula sylvatica, a Juncaceae not yet extensively studied, in the context of osteoarthritis. (2) The Luzula sylvatica Ethanol extract (LS-E) was used to test the production of reactive oxygen species (ROS) by leucocytes, the IL1β and PGE2 production by peripheral blood mononuclear cells (PBMCs), the production of EP4, and the activation of NFκB in THP-1, as well as the IL1β-activated normal human knee articular chondrocytes (NHAC-Kn) gene expression, grown in monolayers or maintained in alginate beads. (3) Organic acids, caffeoylquinic acids, quercetin and luteolin, compounds frequently found in this family were identified. The LS-E exhibited inhibited ROS formation. The LS-E did not affect NFκB activation and IL1β secretion but dampened the secretion of PGE2 by PBMCs and the presence of EP4 in THP-1. It also modulated the expression of NHAC-Kn in both models and inhibited the expression of several proteases and inflammatory mediators. (4) Luzula sylvatica might supply interesting antioxidant protection against cartilage damages and lessen joint inflammation, notably by decreasing PGE2 secretion in the synovial fluid. Moreover, it could act directly on chondrocytes by decreasing the expression of proteases and, thus, preventing the degradation of the extracellular matrix.  相似文献   
106.
Abstract

A detailed identification, using X-ray microtomography, of the filament trajectories within twisted single and multi-ply continuous filament yarns is presented in this article, to accurately determine the distributions of orientations of filaments which govern the mechanical behavior of those yarns and the mechanisms of failure. The resolution of the images obtained by means of the X-ray microtomography experimental setup associated to the capabilities of an in-house developed image processing software allowed the reconstruction of the trajectories of almost all filaments within different yarn specimens. Various structural information are derived from these trajectories, dealing in particular with the orientation of individual segments of filaments with respect either to the ply trajectory or to the yarn axis. Compared to orientation distributions provided by different analytical models available in the literature, those resulting from reconstructed trajectories show similar global trends, while providing more details in peripheral regions and regions close to contact zones between plies. Maps of radial and spatial distributions of orientations provide a comprehensive representation of how filaments are oriented within the plies, which gives valuable insight into the inner structural arrangement of fibers which is one of the sources of nonlinearities in the mechanical behavior of filament yarns.  相似文献   
107.
This paper presents a diffusion method for generating terrains from a set of parameterized curves that characterize the landform features such as ridge lines, riverbeds or cliffs. Our approach provides the user with an intuitive vector‐based feature‐oriented control over the terrain. Different types of constraints (such as elevation, slope angle and roughness) can be attached to the curves so as to define the shape of the terrain. The terrain is generated from the curve representation by using an efficient multigrid diffusion algorithm. The algorithm can be efficiently implemented on the GPU, which allows the user to interactively create a vast variety of landscapes.  相似文献   
108.
The performances of new bio-sourced solvents, the short chain mono- and di-alkyl isosorbide ethers, have been determined and compared to benchmark bitumen fluxes. The influences of fluxes and temperature on the Newtonian viscosity have been assessed. The various fluxes appear to impact also on the visco-elastic behaviour of paving bitumen and dimethyl isosorbide ether (DMI) exhibits good fluxing properties. This bio-sourced solvent has also the property to be fully miscible with water. The bitumen hardness recovery can consequently occur from two different phenomena: evaporation and diffusion from the bitumen to water, making this solvent an appropriate bitumen flux for rainy seasons.  相似文献   
109.
Sun J  Fu K  Wang A  Lin AW  Utzinger U  Drezek R 《Applied optics》2006,45(31):8152-8162
Accurate recovery of tissue optical properties from in vivo spectral measurements is crucial for improving the clinical utility of optical spectroscopic techniques. The performance of inversion algorithms can be optimized for the specific fiber optic probe illumination-collection geometry. A diffusion-theory-based inversion method has been developed for the extraction of tissue optical properties from the shape of normalized tissue diffusion reflectance spectra, specifically tuned for a fiber probe that comprises seven hexagonally close-packed fibers. The central fiber of the probe goes to the spectrometer as the detecting fiber, and the surrounding six outer fibers are connected to the white-light source as illumination fibers. The accuracy of the diffusion-based inversion algorithm has been systematically assessed against Monte Carlo (MC) simulation as a function of probe geometry and tissue optical property combinations. By use of this algorithm, the spectral absorption and scattering coefficients of normal and cancerous tissue are efficiently retrieved. Although there are significant differences between the diffusion approximation and the MC simulation at short source-detector (SD) separations, we show that with our algorithm the tissue optical properties are well retrieved within the SD separation of 0.5-3 mm that is compatible with endoscopic specifications. The presented inversion method is computationally efficient for eventual real-time in vivo tissue diagnostics application.  相似文献   
110.
A thermomechanical model of the FZG test rig is presented. The numerical model is based on the thermal network method and takes into account power losses due to tooth friction, rolling element bearings (REBs), oil churning, and shaft seals. Some measurements underline that REB rings run at different temperatures. To investigate this difference, several REB models are proposed and compared to measurements. Their influence on the global thermal behavior of the gear unit is discussed and analyzed.  相似文献   
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