Results 111 to 120 of about 406,237 (253)

Isotropic Curvature and the Ricci Flow [PDF]

International Mathematics Research Notices, 2009
In this paper, we study the Ricci flow on higher dimensional compact manifolds. We prove that nonnegative isotropic curvature is preserved by the Ricci flow in dimensions greater than or equal to four. In order to do so, we introduce a new technique to prove that curvature functions defined on the orthonormal frame bundle are preserved by the Ricci ...
openaire   +4 more sources

On totally umbilical and minimal surfaces of the Lorentzian Heisenberg groups

Mathematische Nachrichten, Volume 298, Issue 6, Page 1922-1942, June 2025.
Abstract This paper has manifold purposes. We first introduce a description of the Gauss map for submanifolds (both spacelike and timelike) of a Lorentzian ambient space and relate the conformality of the Gauss map of a surface to total umbilicity and minimality.
Giovanni Calvaruso, Marco Castrillón‐Lopez, Lorenzo Pellegrino   +2 more
wiley   +1 more source

Charting cellular differentiation trajectories with Ricci flow

Nature Communications
Complex biological processes, such as cellular differentiation, require intricate rewiring of intra-cellular signalling networks. Previous characterisations revealed a raised network entropy underlies less differentiated and malignant cell states.
Anthony Baptista, Ben D. MacArthur, Christopher R. S. Banerji   +2 more
doaj   +1 more source

Structural properties of the sets of positively curved Riemannian metrics on generalized Wallach spaces

Қарағанды университетінің хабаршысы. Математика сериясы
In the present paper sets related to invariant Riemannian metrics of positive sectional and (or) Ricci curvature on generalized Wallach spaces are considered.
N.A. Abiev
doaj   +1 more source

Curvature estimates for the Ricci flow I [PDF]

Calculus of Variations and Partial Differential Equations, 2007
In this paper we present several curvature estimates and convergence results for solutions of the Ricci flow. The curvature estimates depend on smallness of certain local space-time integrals of the norm of the Riemann curvature tensor, while the convergence results require finiteness of space-time integrals of the norm of the Riemann curvature tensor.
openaire   +4 more sources

The production of terra sigillata in Arezzo, Central Italy: an archaeometric investigation

Archaeometry, Volume 67, Issue 3, Page 604-624, June 2025.
Abstract This work deals with the archaeometric investigation on 25 fragments of terra sigillata (red‐coated ceramic ware and moulds) found in the city of Arezzo, Tuscany (central Italy), and attributed to several important workshops from the first century BCE to the second century CE.
Maria Emanuela Mascaro, Emma Cantisani, Marilena Ricci, Pasquino Pallecchi, Silvia Vilucchi, Maria Chiara Dalconi, Lara Maritan   +6 more
wiley   +1 more source

Targeting Cancer Cell Proliferation Using Piperazine‐Linked Quinolinequinones: Mechanism and Metabolic Profile

Chemical Biology &Drug Design, Volume 105, Issue 6, June 2025.
We examined the quinolinequinones' (QQ1‐ 7) effects on cancer cell lines. The most potent compound was QQ1 against ACHN cells with an IC50 value of 1.5 ± 0.16 μM. For better understanding, the effects of QQ1 on apoptosis, cell cycle, and oxidative stress were investigated. QQ1 inhibited ACHN cell proliferation via cell cycle arrest.
Ayse Mine Yilmaz, Ayse Tarbin Jannuzzi, Abanish Biswas, Subodh Mondal, Vinay N. Basavanakatti, Hatice Yıldırım, Mahmut Yıldız, Nilüfer Bayrak, Venkatesan Jayaprakash, Amaç Fatih TuYuN   +9 more
wiley   +1 more source

Certain results on tangent bundle endowed with generalized Tanaka Webster connection (GTWC) on Kenmotsu manifolds

AIMS Mathematics
This work studies the complete lifts of Kenmotsu manifolds associated with the generalized Tanaka-Webster connection (GTWC) in the tangent bundle.
Rajesh Kumar , Sameh Shenawy , Lalnunenga Colney, Nasser Bin Turki   +3 more
doaj   +1 more source

η-Ricci Solitons on Sasakian 3-Manifolds

Annals of the West University of Timisoara: Mathematics and Computer Science, 2017
In this paper we study η-Ricci solitons on Sasakian 3-manifolds. Among others we prove that an η-Ricci soliton on a Sasakian 3-manifold is an η-Einstien manifold.
Majhi Pradip, De Uday Chand, Kar Debabrata   +2 more
doaj   +1 more source

The Great Barrier Reef, a center for Pelagophyceae (Heterokontophyta) diversity, including a new genus and seven new species

Journal of Phycology, Volume 61, Issue 3, Page 678-698, June 2025.
Abstract The pelagophytes are a morphologically diverse class of marine heterokont algae defined by deoxyribonucleic acid (DNA) gene sequences, the presence of a multilayered, perforated theca (PT), and the novel role of the Golgi apparatus in the formation and secretion of the PT, as well as materials for the synthesis of the outer extracellular ...
Richard Wetherbee, Allison van de Meene, Riyad Hossen, Robert A. Andersen, Heroen Verbruggen   +4 more
wiley   +1 more source