Results 91 to 100 of about 10,739 (275)

Modelling rigid origami with quaternions and dual quaternions

Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2010
This paper examines the mathematical modelling of rigid origami, a type of origami where all the panels are rigid and can only rotate about crease lines. The rotating vector model is proposed, which establishes the loop-closure conditions among a group of characteristic vectors.
Wu, W, You, Z
openaire   +3 more sources

Dynamic Active Constraints for Surgical Robots using Vector Field Inequalities

, 2019
Robotic assistance allows surgeons to perform dexterous and tremor-free procedures, but robotic aid is still underrepresented in procedures with constrained workspaces, such as deep brain neurosurgery and endonasal surgery.
Adorno, Bruno V., Harada, Kanako, Marinho, Murilo M., Mitsuishi, Mamoru   +3 more
core   +1 more source

Aggressive prostate cancer is associated with pericyte dysfunction

Molecular Oncology, EarlyView.
Tumor‐produced TGF‐β drives pericyte dysfunction in prostate cancer. This dysfunction is characterized by downregulation of some canonical pericyte markers (i.e., DES, CSPG4, and ACTA2) while maintaining the expression of others (i.e., PDGFRB, NOTCH3, and RGS5).
Anabel Martinez‐Romero, Ane Martinez‐Larrinaga, Joaquim Grego‐Bessa, Saioa Garcia‐Longarte, Hielke van Splunder, Ianire Astobiza, Amaia Ercilla, Laura Bozal‐Basterra, Isabel Mendizabal, Pilar Villacampa, Arkaitz Carracedo, Mariona Graupera   +11 more
wiley   +1 more source

On tertions and dual numbers [PDF]

Notes on Number Theory and Discrete Mathematics
In a previous author's paper [1], the mathematical object called "tertion" was discussed. Some operations over tertions were introduced and their properties were studied. There, it was showed that the complex numbers and quaternions can be represented by
Krassimir T. Atanassov
doaj   +1 more source

Applications of hypercomplex automorphic forms in Yang-Mills gauge theories [PDF]

, 2013
In this paper we show how hypercomplex function theoretical objects can be used to construct explicitly self-dual SU(2)-Yang-Mills instanton solutions on certain classes of conformally flat 4-manifolds.
Krausshar, Rolf Soeren, Tolksdorf, Jürgen   +1 more
core  

Puzzling the 120-cell

, 2015
We introduce Quintessence: a family of burr puzzles based on the geometry and combinatorics of the 120-cell. We discuss the regular polytopes, their symmetries, the dodecahedron as an important special case, the three-sphere, and the quaternions. We then
Schleimer, Saul, Segerman, Henry
core   +1 more source

Plasma extrachromosomal circular DNA as a biomarker in EGFR‐targeted therapy of non‐small cell lung cancer

Molecular Oncology, EarlyView.
Detection of extrachromosomal circular DNA (eccDNA) in plasma samples from EGFR‐mutated non‐small cell lung cancer patients. Plasma was collected before and during treatment with the EGFR‐tyrosine kinase inhibitor osimertinib. Plasma eccDNA was detected in all cancer samples, and the presence of the EGFR gene on eccDNA serves as a potential biomarker ...
Simone Stensgaard, Sarmad Mehmood, Eva Boysen Fynboe Ebert, Peter Meldgaard, Anindya Dutta, Boe S. Sorensen   +5 more
wiley   +1 more source

Time-Reversal Symmetry in Non-Hermitian Systems

, 2011
For ordinary hermitian Hamiltonians, the states show the Kramers degeneracy when the system has a half-odd-integer spin and the time reversal operator obeys \Theta^2=-1, but no such a degeneracy exists when \Theta^2=+1.
Berry, K. Esaki, K. Hasebe, M. Kohmoto, M. Sato   +4 more
core   +1 more source

Cis‐regulatory and long noncoding RNA alterations in breast cancer – current insights, biomarker utility, and the critical need for functional validation

Molecular Oncology, EarlyView.
The noncoding region of the genome plays a key role in regulating gene expression, and mutations within these regions are capable of altering it. Researchers have identified multiple functional noncoding mutations associated with increased cancer risk in the genome of breast cancer patients.
Arnau Cuy Saqués, Aracele Martinez‐Mendez, John Crown, Alex Eustace   +3 more
wiley   +1 more source

Spinor fields without Lorentz frames in curved spacetime using complexified quaternions

, 2009
Using complexified quaternions, a formalism without Lorentz frames, and therefore also without vierbeins, for dealing with tensor and spinor fields in curved spacetime is presented.
Fock V., Green M. B., John Fredsted, Misner C. W., Weinberg S.   +4 more
core   +4 more sources