Neurostimulatory and ablative treatment options in major depressive disorder: a systematic review

Introduction Major depressive disorder is one of the most disabling and common diagnoses amongst psychiatric disorders, with a current worldwide prevalence of 5-10% of the general population and up to 20-25% for the lifetime period. Historical perspective Nowadays, conventional treatment includes psychotherapy and pharmacotherapy; however, more than 60% of the treated patients respond unsatisfactorily, and almost one fifth becomes refractory to these therapies at long-term follow-up. Nonpharmacological techniques Growing social incapacity and economic burdens make the medical community strive for better therapies, with fewer complications. Various nonpharmacological techniques like electroconvulsive therapy, vagus nerve stimulation, transcranial magnetic stimulation, lesion surgery, and deep brain stimulation have been developed for this purpose. Discussion We reviewed the literature from the beginning of the twentieth century until July 2009 and described the early clinical effects and main reported complications of these methods. © The Author(s) 2010.Link_to_subscribed_fulltex

The interaction of rubidium atoms with a model molecule for polyacetylene: a photoelectron spectroscopy investigation

The interaction of rubidium, a first group metal, with (alpha,omega-diphenyltetradecaheptaene) (DP7), a diphenylpolyene having seven double bonds in the polyene chain, has been studied by means of X-ray and UV photoelectron spectroscopy. DP7 can be considered as a model molecule for polyacetylene since the frontier pi-orbitals are mainly localized on the polyene part of the molecule. The experimental data are interpreted with the help of related experimental data from sodium-doping of DP7 and quantum chemical calculations. The interaction with rubidium results in n-type doping of the DP7, i.e., an electron-transfer process from the metal to the pi-conjugated system occurs. The doping process affects mainly the polyene part of the molecule, and new electronic states are created in the previously forbidden energy gap. At low doping levels, it appears that one new broad peak is developed in the band gap and, most important, a finite density of states at the Fermi energy can be detected. Upon further doping, there is a slight shift of the single peak, and a second peak is formed. The evolution of the new doping-induced states can be explained in terms of a transition from a polaron-like situation to a soliton-antisoliton pair formation

Quantum interference in organic solid

We demonstrate high contrast quantum interference between one-photon and three-photon absorption pathways in an organic solid at room temperature. Illumination of a thin polymer film activated with fluorescing dendrimer chromophores of large three photon absorption cross section with two simultaneous femtosecond pulses at near-IR frequency. and its third harmonic UV frequency 3. results in a spatial interference fringe pattern observable by eye. (C) 2005 Optical Society of America