This correspondence addresses the inversion of 3-D transformation fields, which is a problem that typically arises in image warping problems. A topology preserving parametric B-spline-based representation of the deformation field is considered. Topology preservation ensures that the transformation is a one-to-one mapping and consequently that it is invertible. Inverting such transformation fields amounts to solving a system of nonlinear equations. To tackle this problem, we rely on interval analysis techniques. The proposed algorithm yields a solution whose accuracy is user-controlled. This method may be extended to any dense transformation field and also to deformations defined on a grid of points, by considering a projection in the space of topology preserving B-spline-based deformation fields. The performance of the algorithm is illustrated on transformation fields coming from intersubject brain registration.
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http://dx.doi.org/10.1109/TIP.2008.2002310 | DOI Listing |
J Chem Phys
January 2025
Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan.
The self-consistent field (SCF) procedure is the standard technique for solving the Hartree-Fock and Kohn-Sham density functional theory calculations, while convergence is not theoretically guaranteed. Direct minimization methods, such as the augmented Lagrangian method (ALM) and second-order SCF (SOSCF), obtain the SCF solution by minimizing the Lagrangian with the gradient. In SOSCF, molecular orbitals are optimized by truncating the Taylor expansion of a unitary matrix represented in exponential form to ensure the orthonormality condition.
View Article and Find Full Text PDFChemSusChem
January 2025
Nanjing Forestry University, College of Light Industry and Food Engineering, CHINA.
Based on the concept "Derived from Agroforestry, belong to (Servicing) Agroforestry", we herein achieved the tandem catalytic transformation of lignin to phenolic aryl acrylic esters, which can work as plant growth regulators. The transformation involves the first catalytic oxidative fractionation (COF) of lignin into aromatic aldehydes, which can further undergo Knoevenagel condensation with acids/esters with active Cα-H to generate the phenolic aryl acrylic esters. For the first lignin transformation, the Cu salt (CuSO4) in a 7.
View Article and Find Full Text PDFAdv Mater
January 2025
Faculty of Chemistry and Chemical Engineering, Shantou University, Shantou, 515063, P. R. China.
Photocatalytic conversion of CO and HO into high-value-added C2 fuels remains a tough challenge, mainly due to the insufficient concentration of photogenerated electrons for the instability of C1 intermediates, which often tend to desorb easily and disable to form C─C bonds. In this work, photoreduction of CO-to-CH is successfully achieved by introducing adjacent C, N dual-vacancy sites within the heptazine rings of ultrathin g-CN, which results in the opening of two neighboring heptazine rings and forms a distinctive dipole-limited domain field (DLDF) structure. In situ X-ray photoelectron spectra and in situ fourier transform infrared spectra provide direct evidence of the rapid accumulation and transformation of C1 intermediates, especially CO and CHO, within the DLDF.
View Article and Find Full Text PDFAm J Biol Anthropol
January 2025
Mandatory Center of Expertise for the Curation and Management of Archaeological Collections, St. Louis District, U.S. Army Corps of Engineers, St. Louis, Missouri, USA.
The collections of human remains within our university laboratories and classrooms are considered by many to be integral to teaching osteology. However, as an outgrowth of the Western scientific tradition of mind/body dualism, human remains within skeletal teaching collections are often regarded differently than those in museums or applied contexts. From processing to storage, the personhood of each individual becomes abstracted as we purchase, "inherit," handle, organize, and digitally scan their bones for teaching purposes.
View Article and Find Full Text PDFFront Chem
December 2024
Department of Chemistry, University of Wyoming, Laramie, WY, United States.
Covalent integration of polymers and porous organic frameworks (POFs), including metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and hydrogen-bonded organic frameworks (HOFs), represent a promising strategy for overcoming the existing limitations of traditional porous materials. This integration allows for the combination of the advantages of polymers, i.e.
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