Short exposure of the spores of Cheilanthes farinosa to low intensity red light promotes their germination, which is not reversed by a subsequent exposure to far red light. Germination is, however, inhibited by blue light administered before or after red light. Inhibition of germination by blue light is annulled by exposure to a higher intensity of red light, and germination of the repromoted spores is inhibited by far red light. Mutual photoreversibility of germination is also observed in repromoted spores irradiated successively with far red and red light. Although germination appears to be basically under phytochrome control, it is postulated that the presence of a blue light-absorbing pigment interferes with phytochrome transformations in the spores.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC366255 | PMC |
http://dx.doi.org/10.1104/pp.51.2.306 | DOI Listing |
Nanoscale
January 2025
Theory of Condensed Matter Group, Cavendish Laboratory, University of Cambridge, J.J.Thomson Avenue, Cambridge CB3 0HE, UK.
Benefiting from improved stability due to interlayer van der Waals interactions, few-layer fullerene networks are experimentally more accessible compared to monolayer polymeric C. However, there is a lack of systematic theoretical studies on the material properties of few-layer C networks. Here, we compare the structural, electronic and optical properties of bilayer and monolayer fullerene networks.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
Laboratory of Advanced Computation and Theory for Materials and Chemistry, Department of Chemistry, National Institute of Technology Warangal (NITW), Warangal, Telangana-506004, India.
The optical control of physiological processes with high precision using photoswitches is an emerging strategy for non-invasive diagnosis and therapies, providing innovative solutions to complex biomedical challenges. Light-responsive cyclic conjugated-dienes (cCDs) have long been recognized for their 4π-photocyclization; however, photoswitching behaviour in medium-sized cCDs has recently been reported, representing a pioneering discovery in the field. Reinforced by previous experimental evidence corroborating the Woodward-Hoffmann rules, this report provides insight into the origin of the exotic dual photoexcitation mechanism devised to achieve thermo-reversible photoswitching in large cCDs with cyclodeca-1,3-diene as a prototype.
View Article and Find Full Text PDFMicro light-emitting diodes (µLEDs), crucial for advanced displays and communication systems, face efficiency challenges due to sidewall defects. This study investigates the impact of various passivation layers, including SiO, AlO, and HfO, on AlGaInP-based 620 nm red µLEDs. We fabricated devices with two mesa sizes and demonstrated that atomic layer deposition (ALD) passivation, especially with HfO, significantly enhances performance.
View Article and Find Full Text PDFBioorg Chem
January 2025
CSIR- Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India. Electronic address:
The expanding prevalence of microbial resistance to conventional treatments has triggered a race to develop alternative/improved strategies to combat drug-resistant microorganisms in an efficient manner. Here, the lethal impact of the biosynthesized gold nanoparticles (AuNPs) against multi-drug resistant (MDR) bacteria has been elucidated. AuNPs, synthesized from the extracts of the fruit, leaf and peel of the Citrus maxima plant, were physicochemically characterized by UV-Vis spectrophotometry, Dynamic Light Scattering (DLS), electron microscopy and spectroscopic techniques not only confirmed the production of AuNPs of size below 100 nm but also identified the phytochemicals adsorbed onto the surface of NPs.
View Article and Find Full Text PDFDalton Trans
January 2025
Department of Chemistry, Handique Girls' College, Guwahati 781001, Assam, India.
Photoactive complexes of bioessential 3d metals, activable within the phototherapeutic window (650-900 nm), have gained widespread interest due to their therapeutic potential. Herein, we report the synthesis, characterization, and light-enhanced anticancer and antibacterial properties of four new dinuclear Co(II) complexes: [Co(phen)(cat)] (Co-1), [Co(dppz)(cat)] (Co-2), [Co(phen)(esc)] (Co-3), and [Co(dppz)(esc)] (Co-4). In these complexes, phen (1,10-phenanthroline) and dppz (dipyrido[3,2-:2',3'-]phenazine) act as neutral N,N-donor ligands, while cat and esc serve as O,O-donor catecholate ligands derived from catechol (1,2-dihydroxybenzene) and esculetin (6,7-dihydroxy coumarin).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!