Covalently Linked Donor-Acceptor Dyad for Efficient Single Material Organic Solar Cells

A novel covalently linked donor-acceptor dyad comprising a dithienopyrrol-based oligomeric donor and a fullerene acceptor was synthesized and characterized. The concomitant effect of favorable optoelectronic properties, energy levels of the frontier orbitals, and ambipolar charge transport enabled the application of the dyad in simplified solution-processed single material organic solar cells reaching a power conversion efficiency of 3.4%.<br /

Enhanced and Selective Lipid Extraction from the Microalga P. tricornutum by Dimethyl Carbonate and Supercritical CO2Using Deep Eutectic Solvents and Microwaves as Pretreatment

Microalgae are promising alternative sources of several bioactive compounds that are useful for human applications. However, lipids are traditionally extracted with toxic organic solvents (e.g., mixtures of chloroform and methanol or hexane). In this work, we develop a new lipid extraction protocol for obtaining a fatty-acids-rich extract from the diatom Phaeodactylum tricornutum. Deep eutectic solvents (DESs) and microwaves (MWs) were investigated as pretreatments for environmentally friendly solvent extractions using dimethyl carbonate (DMC) and supercritical CO2(scCO2). Pretreatments with various DESs formed by choline chloride (ChCl) and different hydrogen-bond donors (oxalic acid, levulinic acid, urea, ethylene glycol, and sorbitol) were tested in combination with DMC extraction. DESs formed by ChCl and carboxylic acids gave the best results, increasing both the selectivity and the total fatty acid (TFA) extraction yield of DMC (by 16% and 80%, respectively). DESs combined with MW heating followed by DMC extraction allowed a TFA yield and fatty acid profile comparable to those of the traditional Bligh and Dyer extraction method to be reached, along with a much better selectivity (88% vs 35%). This pretreatment was also demonstrated to significantly improve the extraction efficiency of scCO2, increasing the TFA yield by a factor of 20 and providing highly purified triglyceride extracts

Cancer patients' emotional distress, coping styles and perception of doctor-patient interaction in European cancer settings

Objective: As a part of a European study, we cross-culturally examined the rate of emotional distress and maladaptive coping and their association with cancer patients' satisfaction with their interactions with the physician responsible for their care. Methods: Cancer patients (n = 302) from one Middle European (Austria) and two Southern European (Italy, Spain) countries completed the NCCN Distress Thermometer (DT), the Mini-Mental Adjustment to Cancer (Mini-MAC) Anxious Preoccupation (AP) and Hopelessness (H) sub-scales, and the Physician Patient Satisfaction with Doctors Questionnaire (PSQ). Results: The prevalence of emotional distress (DT caseness) was 60% (26.1% mild, 18.8% moderate, and 14.9% severe distress). Maladaptive coping (Mini-MAC cases) was found in 22.8% (hopeless cases), and 22.5% (anxious preoccupation cases). PSQ-MD was significantly correlated with Mini-MAC/H and Mini-Mac/AP, while PSQ-PS was negatively correlated with Mini-MAC/H. DT cases and those with higher levels of hopelessness reported higher scores on PSQ-MD and lower on PSQ-PS than non-cases. Some differences were found between countries both as far as patients' coping and perception of the interaction with doctors. In hierarchical multiple regression analysis, after adjusting for socio-demographic and medical variables, Mini-MAC/H significantly predicted the scores on PSQ-MD (positive direction) and PSQ-PS (negative direction). Significance of results: The study confirms that about one out of three cancer patients have moderate to high level of emotional distress and about one out of four, clinically significant maladaptive coping. Also, patients showing hopelessness and distress tended to perceive their doctors as both disengaged and less supportive. These results highlights the need for physicians to monitor their patient's level of distress and coping mechanisms and to adjust their own relational and communication style according to patients' psychological condition. Also, cross-cultural issues should be taken into account when exploring psychosocial variables and cancer patients' perception of and satisfaction with the interaction with their doctors

Molecular Donor–Acceptor Dyads for Efficient Single‐Material Organic Solar Cells

Single-material organic solar cells (SMOSCs) promise several advantages withrespect to prospective applications in printed large-area solar foils. Only onephotoactive material has to be processed and the impressive thermal and pho-tochemical long-term stability of the devices is achieved. Herein, a novel structuraldesign of oligomeric donor–acceptor (D–A) dyads 1–3 is established, in which anoligothiophene donor and fullerene acceptor are covalently linked by a exiblespacer of variable length. Favorable optoelectronic, charge transport, andself-organization properties of the D–A dyads are the basis for reaching powerconversion efciencies up to 4.26% in SMOSCs. The dependence of photovoltaicand charge transport parameters in these ambipolar semiconductors on thespecic molecular structure is investigated before and after post-treatment bysolvent vapor annealing. The inner nanomorphology of the photoactive lms ofthe dyads is analyzed with transmission electron microscopy (TEM) and grazing-incidence wide-angle X-ray scattering (GIWAXS). Combined theoretical calculationsresult in a lamellar supramolecular order of the dyads with a D–A phase separationsmaller than 2 nm. The molecular design and the precise distance between donorand acceptor moieties ensure the fundamental physical processes operative inorganic solar cells and provide stabilization of D–A interfaces