Excited Charge Transfer Promoted Electron Transfer in all Perylenediimide Derived, Wide-Band Capturing Conjugates: A Mimicry of the Early Events of Natural Photosynthesis.

Fundamental discoveries in electron transfer advance scientific and technological advancements. It is suggested that in plant and bacterial photosynthesis, the primary donor, a chlorophyll or bacteriochlorophyll dimer, forms an initial excited symmetry-breaking charge transfer state (CT*) upon photoexcitation that subsequently promotes sequential electron transfer (ET) events. This is unlike monomeric photosensitizer-bearing donor-acceptor dyads where ET occurs from the excited donor or acceptor (D* or A*).

Panchromatic Light-Capturing Bis-styryl BODIPY-Perylenediimide Donor-Acceptor Constructs: Occurrence of Sequential Energy Transfer Followed by Electron Transfer.

Invited for the cover of this issue are the groups of Fernando Fernández-Lázaro and Ángela Sastre-Santos at the Universidad Miguel Hernández, Elche, Spain, and Francis D'Souza at the University of North Texas at Denton, Texas, USA. The image depicts the structure and properties of bis-styryl BODIPY-perylenediimide donor-acceptor constructs. Read the full text of the article at 10.

Panchromatic Light-Capturing Bis-styryl BODIPY-Perylenediimide Donor-Acceptor Constructs: Occurrence of Sequential Energy Transfer Followed by Electron Transfer.

Two wide-band-capturing donor-acceptor conjugates featuring bis-styrylBODIPY and perylenediimide (PDI) have been newly synthesized, and the occurrence of ultrafast excitation transfer from the PDI* to BODIPY, and a subsequent electron transfer from the BODIPY* to PDI have been demonstrated. Optical absorption studies revealed panchromatic light capture but offered no evidence of ground-state interactions between the donor and acceptor entities. Steady-state fluorescence and excitation spectral recordings provided evidence of singlet-singlet energy transfer in these dyads, and quenched fluorescence of bis-styrylBODIPY emission in the dyads suggested additional photo-events.

Distance-Dependent Electron Transfer Kinetics in Axially Connected Silicon Phthalocyanine-Fullerene Conjugates.

The front cover artwork is provided by the groups of Prof. Sastre-Santos, Prof. D'Souza, and Prof.

Distance-Dependent Electron Transfer Kinetics in Axially Connected Silicon Phthalocyanine-Fullerene Conjugates.

The effect of donor-acceptor distance in controlling the rate of electron transfer in axially linked silicon phthalocyanine-C dyads has been investigated. For this, two C-SiPc-C dyads, 1 and 2, varying in their donor-acceptor distance, have been newly synthesized and characterized. In the case of C-SiPc-C 1 where the SiPc and C are separated by a phenyl spacer, faster electron transfer was observed with k equal to 2.

Distance Matters: Effect of the Spacer Length on the Photophysical Properties of Multimodular Perylenediimide-Silicon Phthalocyanine-Fullerene Triads.

A multimodular donor-acceptor conjugate featuring silicon phthalocyanine (SiPc) as the electron donor, and two electron acceptors, namely tetrachloroperylenediimide (PDI) and C , placed at the opposite ends of the SiPc axial positions, was newly designed and synthesized, and the results were compared to the earlier reported PDI-SiPc-C triad. Minimal intramolecular interactions between the entities was observed. Absorption, fluorescence, computational and electrochemical studies were performed to evaluate the excitation energy, geometry and electronic structure, and energy levels of different photoevents.

A survey on literature based discovery approaches in biomedical domain.

Literature Based Discovery (LBD) refers to the problem of inferring new and interesting knowledge by logically connecting independent fragments of information units through explicit or implicit means. This area of research, which incorporates techniques from Natural Language Processing (NLP), Information Retrieval and Artificial Intelligence, has significant potential to reduce discovery time in biomedical research fields. Formally introduced in 1986, LBD has grown to be a significant and a core task for text mining practitioners in the biomedical domain.

Multichromophoric Perylenediimide-Silicon Phthalocyanine-C System as an Artificial Photosynthetic Analogue.

Sequential photoinduced energy transfer followed by electron transfer and the formation of charge-separated states, which are primary events of natural photosynthesis, have been demonstrated in a newly synthesized multichromophoric covalently linked triad, PDI-SiPc-C . The triad comprises a perylenediimide (PDI), which primarily fulfils antenna and electron-acceptor functionalities, silicon phthalocyanine (SiPc) as an electron donor, and fulleropyrrolidine (C ) as a second electron acceptor. The multi-step convergent synthetic procedure developed here produced good yields of the triad and control dyads, PDI-SiPc and SiPc-C .

Impact of sex and gonadal steroids on neonatal brain structure.

There are numerous reports of sexual dimorphism in brain structure in children and adults, but data on sex differences in infancy are extremely limited. Our primary goal was to identify sex differences in neonatal brain structure. Our secondary goal was to explore whether brain structure was related to androgen exposure or sensitivity.