In this paper, we explore how graph-spectral methods can be used to develop a new shape-from-shading algorithm. We characterize the field of surface normals using a weight matrix whose elements are computed from the sectional curvature between different image locations and penalize large changes in surface normal direction. Modeling the blocks of the weight matrix as distinct surface patches, we use a graph seriation method to find a surface integration path that maximizes the sum of curvature-dependent weights and that can be used for the purposes of height reconstruction. To smooth the reconstructed surface, we fit quadrics to the height data for each patch. The smoothed surface normal directions are updated ensuring compliance with Lambert's law. The processes of height recovery and surface normal adjustment are interleaved and iterated until a stable surface is obtained. We provide results on synthetic and real-world imagery.
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http://dx.doi.org/10.1109/tip.2004.828414 | DOI Listing |
JACC Clin Electrophysiol
January 2025
Cardiac Electrophysiology Section, Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Duke Clinical Research Institute, Durham, North Carolina, USA. Electronic address:
Background: In patients with structurally normal hearts, algorithms using surface electrocardiographic P-wave morphology are helpful to predict focal atrial tachycardia (FAT) location. However, these algorithms have not been formally assessed in patients with adult congenital heart disease (ACHD).
Objectives: This study sought to assess the efficacy of FAT-location prediction algorithms in an adult population of patients with ACHD.
Anal Chim Acta
March 2025
College of New Energy Materials and Chemistry, Leshan Normal University, Leshan, Sichuan, 614000, PR China; Sichuan Province Key Laboratory of Natural Products and Small Molecule Synthesis, Leshan, Sichuan, 614000, PR China. Electronic address:
Background: The threat of toxic malathion residues to human health has always been a serious food safety issue. The CRISPR/Cas system represents an innovative detection technology for pesticide residues, but its application to malathion detection has not been reported yet. In addition, the multiple-guide RNA (gRNA) powered-CRISPR/Cas biosensor has the advantages of being fast, sensitive and does not require pre-amplification.
View Article and Find Full Text PDFFood Chem
January 2025
Key Laboratory of Photochemical Biomaterials and Energy Storage Materials, Heilongjiang Province, College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, PR China. Electronic address:
In this study, we designed a molecularly imprinted electrochemical sensor based on the reduced graphene oxide/polydopamine@Mxene (RPM) and FeCu-MOF for the detection of antiviral drug ribavirin (RBV). The RPM composite enhances the active surface area and electron transport capacity of the sensor, and the incorporation of FeCu-MOF can not only further improve the catalytic performance of the material, but also enables the sensor to harness the electrical reduction signal of HO. Furthermore, we developed an optimized molecularly imprinted polymer via density functional theory (DFT) to enhance the sensor's specificity and sensitivity for RBV detection.
View Article and Find Full Text PDFIntegr Environ Assess Manag
January 2025
Faculty of Fine Arts, Design and Architecture Department of Landscape Architecture, Tekirdağ Namık Kemal University, Tekirdağ, Türkiye.
Wetlands provide necessary ecosystem services, such as climate regulation and contribution to biodiversity at global and local scales, and they face spatial changes due to natural and anthropogenic factors. The degradation of the characteristic structure signals potential severe threats to biodiversity. This study aimed to monitor the long-term spatial changes of the Göksu Delta, a critical Ramsar site, using remote sensing techniques.
View Article and Find Full Text PDFInorg Chem
January 2025
Beijing Spacecrafts Manufacturing Factory, Beijing 100094, P. R. China.
The rapid upsurge of metal-organic frameworks (MOFs) has sparked profound interest in their potential as proton conductors for proton exchange membrane fuel cells. However, proton-conducting behaviors of hydrophobic MOFs remain poorly understood compared with their hydrophilic counterparts, largely due to the absence of a microscopic phase separation structure akin to that found in Nafion membranes. Herein, we demonstrate a strategy for regulating the structures and proton conductivities of MOFs by separately incorporating hydrophobic -C(CF)- group alongside hydrophilic -O- and -SO- groups into organic ligands as linkers.
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