Results 71 to 80 of about 8,069 (192)

Origin and Early Evolution of Comet Nuclei [PDF]

, 2008
Foreword.- Origins of Cometary Materials.- Origin of Comet Nuclei and Dynamics.- Reservoir for Comet Material: Circumstellar Grains.- Interstellar Reservoirs of Cometary Matter.- Cometary Refractory Grains: Interstellar and Nebular Sources.- Dynamical Origin of Comets and Their Reservoirs.- Reservoirs for Comets: Compositional Differences Based on ...
openaire   +1 more source

On the Early Thermal Processing of Planetesimals during and after the Giant Planet Instability

The Planetary Science Journal
Born as ice-rich planetesimals, cometary nuclei were gravitationally scattered onto their current orbits in the Kuiper Belt and the Oort Cloud during the giant planets’ dynamical instability in the early stages of our solar system’s history.
Anastasios Gkotsinas, David Nesvorný, Aurélie Guilbert-Lepoutre, Sean N. Raymond, Nathan Kaib   +4 more
doaj   +1 more source

Prolonged exposure to artificial light and carcinogenesis: A systematic review of oncostatic mechanisms associated with melatonin pathways

Photochemistry and Photobiology, EarlyView.
Exposure to artificial light at night (ALAN), particularly at blue wavelengths, disrupts circadian rhythms by suppressing melatonin, thereby increasing cancer susceptibility. This systematic review consolidates evidence linking prolonged ALAN exposure to an elevated risk of breast and prostate tumors.
Gabriel Barboza, Jêmina Oliveira, Antônio Ferreira, Renan Lopes, Marli Cupertino   +4 more
wiley   +1 more source

Direct evidence of singlet molecular oxygen [O2 (1Δg)] production from UVA excited 6‐thioguanine

Photochemistry and Photobiology, EarlyView.
6‐Thioguanine (6‐TGua) is incorporated into DNA as a purine analogue, inhibiting cell replication. Patients treated with 6‐TGua are more prone to developing skin cancer due to the photoexcitation of 6‐TGua by UVA radiation (as illustrated in the Jablonski diagram). Upon exposure to UVA, the excited 6‐TGua generates 1O2.
André L. Lopes, Fernanda M. Prado, Helena C. Junqueira, Marisa H. G. Medeiros, Graziella E Ronsein, Jean Cadet, Paolo Di Mascio   +6 more
wiley   +1 more source

Impact of Seasonal Composition on the Long‐Term Performance of Post‐Consumer Recycled Polypropylene

Journal of Applied Polymer Science, Volume 143, Issue 15, April 15, 2026.
Ten batches of post‐consumer polypropylene recyclate were examined over a period of 15 months. Despite identical MFR and density specifications, there were significant differences in their composition, affecting mechanical performance. Elongation at break and crack resistance varied particularly strongly.
Jessica Hinczica, Linda M. Schatz, Jutta Geier, Mario Messiha, Márton Bredács, Thomas Koch, Gerald Pinter, Florian Arbeiter   +7 more
wiley   +1 more source

The JaCVAM / OECD activities on the comet assay

Frontiers in Genetics, 2015
The in vivo alkaline single cell gel electrophoresis assay, also called alkaline comet assay is a method measuring DNA strand breaks in eukaryotic cells.
Hajime Kojima
doaj   +1 more source

Cytotoxic, Genotoxic, and Mutagenic Effects of Organotellurane RF07 in Female Swiss Mice (Mus musculus)

Chemistry &Biodiversity, Volume 23, Issue 3, March 2026.
ABSTRACT The organotellurane RF07 (RF07) is an organic compound containing tellurium, a rare semi‐metal, and its leishmanicidal and antimalarial activity has already been reported in previous studies. This study evaluated the toxic effects of RF07 at 0.42, 21.37, and 42.75 mg/kg using comet assay, micronucleus test, and hematological/biochemical tests ...
Felipe Emannuel Alvino de Jesus, Octávio Augusto de Carvalho Maia, Rosália Maria Tôrres de Lima, Ag‐Anne Pereira Melo de Meneses, Audinei de Sousa Moura, Antonielly Campinho dos Reis, Maria Luísa Lima Barreto do Nascimento, Taline Alves Nobre, Athanara Alves de Sousa, Shamya Gabriella Corrêa Coelho, Glissia Lysandra dos Santos Marciel, Isabela Ribeiro de Sá Guimarães Nolêto, Adriana Maria Viana Nunes, Rodrigo Luiz Oliveira Rodrigues Cunha, Pedro Marcos de Almeida, Diego Di Felipe Ávila Alcantara, João Marcelo de Castro e Sousa   +16 more
wiley   +1 more source

Dust and gas emission from cometary nuclei: the case of comet 67P/Churyumov–Gerasimenko

Advances in Physics: X, 2018
Comets display with decreasing solar distance an increased emission of gas and dust particles, leading to the formation of the coma and tail. Spacecraft missions provide insight into the temporal and spatial variations of the dust and gas sources located
Tobias Kramer, Matthias Noack, Daniel Baum, Hans-Christian Hege, Eric J. Heller   +4 more
doaj   +1 more source

Zinc induces DNA damage in tobacco roots

Biologia Plantarum, 2013
We applied the alkaline version of the single-cell gel electrophoresis (comet assay) to seedlings of heterozygous tobacco (Nicotiana tabacum L. var. xanthi) treated with zinc acetate dihydrate (20 to 80 mM Zn2+ for 2 h or 2 to 12 mM Zn2+ for 24 h).
D. Procházková, N. Wilhelmová, D. Pavlíková, J. Száková, T. Gichner   +4 more
doaj   +1 more source

Is Micronucleus Assay a Suitable Biomarker for Evaluating the Cancer Risk in Professionals Exposed to Antineoplastic Drugs? A Systematic Review

Journal of Applied Toxicology, Volume 46, Issue 3, Page 733-753, March 2026.
ABSTRACT The widespread use of antineoplastic drugs in cancer treatment has led to significant concerns regarding the potential health risks posed to healthcare professionals involved in the preparation, administration, and handling of these chemical compounds, including genotoxicity.
Thiago Guedes Pinto, Lorrany da Silva Avanci, Gabriel Carvalhal de Aguiar, Daniel Vitor de Souza, Patricia Ramos Cury, Ana Claudia Muniz Renno, Daniel Araki Ribeiro   +6 more
wiley   +1 more source