Organic electronics, an interdisciplinary research area traditionally more connected to organic synthetic chemistry and polymer science than condensed matter physics, is currently undergoing a major transformation. The advent of high mobility small molecule semiconductors and new avenues for scalable thin film and device fabrication introduce a new paradigm in a research field that was historically overwhelmingly focused on polymer-based materials.
At the University of Vermont my research group focuses on exploring excitonic states, low temperature magnetism and spin-dependent exchange interactions in metal and metal-free octabutoxyphthalocyanine (OBPc) crystalline semiconducting thin films that belong to an intermediate regime between a fully localized (Frenkel) and fully delocalized (Wannier) picture of the excitonic behavior. We employ condensed matter experimental approaches (in particular low temperature, polarization-resolved, ultrafast, magneto-spectroscopy) on a quest for signatures of long range interactions such as exciton-phonon coupling and spin exchange in these systems. Recent results include: i) the observation of a low temperature nominally “dark” exciton state that is now optically-allowed because intermolecular interactions led to a breakdown of the selection rules,[1] ii) the surprising discovery of excitonic states localized at the grain boundary that provides new insight on exciton diffusion in these systems,[2] and iii) the direct observation of an MCD signature of an exchange between d-shell electrons of the metal ion and the delocalized π-orbitals of the ligand in transition metal species of MOBPc.[3]
1. Rawat, N., et al. J.Phys. Chem. Lett. 2015, 6(10), 1834-1840.
2. Pan, Z., et al. Nat.Commun. 2015,6.
3. Rawat, N., et al., Sci. Rep. 2015,5, 16536.
Time:
12:00
Location:
“Seminar Room 1”, FORTH’s bldg
Description:
IMBB JOINT COLLOQUIA
Speaker 1: Maria MONASTIRIOTI
Title: "IMBB Retreat Missing Talk".
Speaker 2: Giulia BONETTO (Karagogeos' Lab)
Title: "Microneurotrophins contribute to oligodendrocyte survival in the Cuprizone model of demyelination."
With the exception of a limited number of sites in the body, primary tumors infrequently lead to the demise of cancer patients. Instead, mortality and a significant degree of morbidity result from the growth of secondary tumors in distant organs. Malignant tumors release both lymphand
angio- genic factors, through two specific processes termed lymphangiogenesis and angiogenesis, respectively. In addition, recent experimental evidence shows that tumors initiate their own innervation by the release of neurotrophic factors (neoneurogenesis). The relationship between tumor progression and the nervous system is a complex and poorly understood part of cancer pathogenesis. It is likely that this process is regulated by a multitude of factors in the tumor/nerve microenvironment; these pathways are even further complicated by treatment and disease history as well as other genetic and socioeconomic factors. It is therefore important to study the interactions between the nervous system and tumor cells through mathematical/computational modelling: in this way we will take into account the most significant elements of the plethora of interacting pathways regulating this process. The present work is a first attempt to model the neurobiological aspect of cancer development through a system of differential equations.
NOTE: This is a joint work with Dr. Arianna Bianchi (University of Alberta, Kanada) and Prof. Konstantinos Syrigos (University of Athens, Greece).
Time:
12:00 - 13:00
Location:
“Seminar Room 1”, FORTH’s bldg
Description:
IMBB JOINT COLLOQUIA
Speaker 1: Giulia BONETTO (Karagogeos' Lab)
Title: "Microneurotrophins contribute to oligodendrocyte survival in the Cuprizone model of demyelination.".
Speaker 2: Effie THYMIAKOU (Kardassis' Lab)
Title: "The role of hepatic and intestinal HNF-4a in lipid and lipoprotein metabolism: in vivo studies".
Maria KLAPA
Principal Researcher (Rank B)
Head, Metabolic Engineering and Systems Biology Laboratory Institute of Chemical Engineering Sciences (ICE-HT - FORTH) Patras, GREECE
Title: "Metabolomics and Metabolic Network Analysis in Systems Biology".
Emre YAKSI
Group Leader - NERF, a joint research initiative between imec
VIB and K.U. Leuven
Assistant Professor - Neurophysiology Department
KU Leuven
Title: "Studying neural computations in zebrafish brain".
The habenula (Hb) is a brain region with increasing popularity due to its strong link to addiction, mood disorders and experience dependent fear. We demonstrated that Hb neurons respond to odors and light asymmetrically. Moreover, we showed that Hb neurons exhibit structured spontaneous activity that is spatially and temporally organized. This spontaneous activity resembles neural attractors, which can switch the preferred state of the Hb and regulate the transmission of sensory information to downstream monoaminergic brainstem nuclei. In order to explore the source of Hb spontaneous activity, we investigate the local connectivity within Hb and the global functional inputs to Hb. Our results showed that recurrent excitatory connections within Hb is important for maintaining spatio-temporal organization of Hb activity. Moreover, we observed that functional inputs form zebrafish homologues of hippocampus (Dl) and amygdala (Dm) and sensory inputs from visual and olfactory systems are the major drivers of spontaneous Hb activity. Our results suggested that these limbic and sensory inputs are integrated in Hb in a non-linear fashion and can regulate sensory representations in Hb. We propose that Hb lies in the heart of a brain wide network and act as “a hub” or “a switchboard”, which can regulate or gate the communication of sensory systems and limbic forebrain areas with the monoaminergic brainstem nuclei that control animal behaviors.
Time:
12:00
Description:
Ioannis SOTIROPOULOS
Life and Health Sciences Research Institute (ICVS)
School of Health Sciences, Campus de Gualtar
University of Minho, Braga
Portugal
Title: "The Stressed brain: a gate along the path from depression to Alzheimer’s disease".
Pavlina HARAMIS
Assistant Professor
Institute of Biology, Leiden University,
Sylvius Laboratory, Rm 06.05.16b,
Sylviusweg 72, 2333 BE Leiden
The Netherlands
Title: "The role of the tumor suppressor LKB1 in starvation-induced autophagy".
Eric CW So, PhD
Professor and Chair in Leukaemia Biology,
Head, Leukaemia and Stem Cell Biology Group,
Department of Haematological Medicine,
King's College London,
The University of London
London, UK
Title: "Targeting oncogenic transcription factors in leukemia: from mechanisms to treatments".