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La Enfermedad Tromboembólica Venosa comprende dos trastornos, el Tromboembolismo Pulmonar y la Trombosis Venosa Profunda (TVP). Esta última se asocia, entre otras causas, a deficiencias enzimáticas del organismo, las cuales favorecen el desarrollo de la enfermedad y sus complicaciones, siendo el síndrome postrombótico la más frecuente. Presentamos el caso de un paciente masculino de 34 años que acude a consulta por presentar aumento de volumen, edema, tensión muscular, dolor y claudicación de ambas extremidades pélvicas a quien se le diagnosticó Trombosis Venosa Profunda Fémoro-Iliaca Bilateral asociado a una triple deficiencia enzimática de Antitrombina III, Proteína C y Proteína S de la coagulación.

While the performance of some emerging solar cell technologies is rocketing, there are other important parameters that also need to be considered for industrialization, including aesthetics, payback time or long-term stability. More specifically, aesthetical features of the solar cells play a very important role in the path towards the integration of these semi-transparent technologies into the buildings and windows of the future. In this work, we have implemented a theoretical methodology to study in depth colour tuning in polymer-based organic photovoltaic cells that uses experimentally complex refractive indices. We compare quantitatively basic interference effects (through active layer thickness), binaries with different donors and different acceptors, and ternary systems where the third component is either active or a simple dye. For hybrid perovskite solar cells, we compare the colour tuning capability of blending and alloying. Additionally, we show that the same theoretical framework can be employed for the so-called inverse problem, i.e. determining the best solar cell parameters (specific materials, donor:acceptor ratio and photoactive film thickness) that can reproduce a desired set of chromaticity coordinates., This work was supported by the Spanish Ministerio de Economía y Competitividad (MINECO); under Grant MAT2015-70850-P (HIBRI2) and No. SEV-2015-0496 in the framework of the Spanish Severo Ochoa Centre of Excellence; EURECAT, Centre Tecnològic de Catalunya through a research contract and European Research Council through project ERC CoG648901.

Terthiophene dyes were synthesized having a carboxylate or a phosphonate moiety at the 2-position which serves as an anchoring group to zinc oxide nanocrystals (ZnO NCs). Electronic absorption and fluorescence measurements, combined with reduction potentials, provided estimates of -1.81 and -1.86 V vs. NHE for the excited state reduction potential of the carboxylate and phosphonate, respectively. Static quenching was observed when the dyes were bound to the surface of acetate-capped ZnO NCs having a diameter of 2.8 nm. Stern-Volmer studies conducted at several dye concentrations established that a minor fraction of the adsorbed dye remained unquenched even at 1 : 1 dye to NC ratios. Adsorption isotherm measurements established that the phosphonate binds more strongly than the carboxylate and that saturation coverage was ∼1.2 dyes per nm2 for both dyes. Ultrafast transient absorption spectroscopic experiments were used to probe excited state dynamics. In the presence of ZnO NCs, disappearance of the singlet excited state of the dye corresponded to appearance of the spectroscopic signature of the oxidized dye with a time constant of 1.5 ± 0.1 and 6.1 ± 0.2 ps, respectively, for the carboxylate and phosphonate dye. The difference in the electron transfer rates was attributed to a larger electronic coupling for the dye having the carboxylate anchoring group.

Oligothiophene dyes with two to five thiophene units were anchored to oleate-capped, quantum-confined zinc oxide nanocrystals (ZnO NCs) through a cyanoacrylate functional group. While the fluorescence of the bithiophene derivative was too weak for meaningful quenching studies, the fluorescence of the dyes with three, four and five thiophene rings was quenched upon binding to the NCs. Ultrafast pump-probe spectroscopy was used to observe the singlet excited states of the free dyes dissolved in dichloromethane as well as attached to a ZnO NC dispersed in the same solvent. When the dyes were bound to ZnO NCs, ultrafast spectroscopic measurements revealed rapid disappearance of the singlet excited state and appearance of a new transient absorption at higher energy that was assigned to the oxidized dye based on the similar absorption observed upon oxidation of the dye using nitrosonium ion. The appearance lifetimes of the oxidized dyes were assigned to the excited state electron transfer and were 36 ± 2, 22.3 ± 3.9, 26.5 ± 1.5 and 19.4 ± 0.8 ps for bi-, ter-, quarter- and quinquethiophene dyes respectively. Two factors contributed to the similarity in the electron transfer lifetime. First the excited state energies of the dyes were similar, and second, the free energy for electron transfer reaction was sufficiently large to move the event into the energy-independent regime.

Ferroelectric perovskite oxides are emerging as a promising photoactive layer for photovoltaic applications due to their very high stability and their alternative ferroelectricity-related mechanism for solar energy conversion that could lead to extraordi-narily high efficiencies. One of the biggest challenges so far is to reduce their band gap towards the visible while simultane-ously retaining ferroelectricity. To address these two issues, herein it is performed an elemental composition engineering of BiFeO3 by substituting Fe by Co cations, as means to tune the characteristics of the transition metal-oxygen bond. We demonstrate by solution processing the formation of epitaxial, pure phase and stable BiFe1-xCoxO3 thin films for x=0.3 and film thickness up to 100 nm. Importantly, the band gap can be tuned from 2.7 eV to 2.3 eV upon cobalt substitution while simultaneously enhancing ferroelectricity. As a proof of concept, non-optimized vertical devices have been fabricated and, reassuringly, the electrical photoresponse in the visible of the Co-substituted phase is improved with respect to the unsubsti-tuted oxide., We would like to acknowledge Prof. Josep Fontcuberta for fruitful discussions and comments on this study and for providing access to his experimental facilities. This research was supported by the Spanish MINECO (“Severo Ochoa” Programme for Centres of Excellence in R&D SEV-2015-0496 and FIPNANOSOLE- 2016, MAT2017-83169-R, MAT2014-51778-C2- 1-R, MAT2015-70850-P, MAT2017-85232-R (AEI/FEDER, EU)), the Generalitat de Catalunya (2017-SGR-1519, 2017 SGR- 1377), the European Research Council-ERC (FOREMAT under grant agreement no. 648901) and “L’Oreal UNESCO For Women in Science”. M.C., J.G. and I.F. acknowledge RyC contracts (2013-12448, 2012-11709 and RYC-2017-22531). I.F. is grateful to MINECO for MAT2015-73839-JIN project. The HRTEM microscopy work was conducted at the Center for Nanophase Materials Sciences at Oak Ridge National Laboratory, which is a DOE Office of Science User Facility.

One of the major bottlenecks in the development of organic photovoltaics is the time needed to evaluate each material system. This time ranges from weeks to months if different variables such as blend composition, thickness, annealing, and additives are to be explored. In this study, the use of lateral gradients is proposed in order to evaluate the photovoltaic potential of a material system up to 50 times faster. A platform that combines blade coating using controllable velocity profiles (thickness gradients) with multichannel dispensers (composition gradients) and controlled lateral annealing variations (nanostructure gradients) is introduced. These samples are then analyzed using photocurrent and Raman imaging in order to correlate one to one the device performance, thickness, composition, and annealing temperature. The strength of the developed technology is shown by optimizing three different systems, namely PCDTBT:PC70BM, PTB7‐Th:PC70BM, and PffBT4T‐2OD:PC70BM, obtaining efficiencies ≈5%, 8%, and 9.5%, respectively, using less than 10 mg of each polymer in the process., The authors are indebted to Dr. Bernhard Dörling for the development of the blade coating accelerating electronics, and Xavier Tejero and Prof. Alejandro Goñi for their help with setting up the LBIC system. The authors would also like to thank Dr. Juan Cabanillas (IMDEA) for useful discussions. The authors would like to acknowledge financial support from the Ministerio de Economía y Competitividad of Spain through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV‐2015‐0496) and project MAT2015‐70850‐P; and the European Research Council (ERC) under grant agreement No. 648901.

We report on a combinatorial optimization procedure applied to heterojunction small molecule organic solar cells made of evaporated copper phthalocyanine (CuPc) and 3,4,9,10-perylenetetracarboxylic bisbenzimidazole (PTCBI). Our strategy consists of depositing both light harvesting compounds as orthogonally arranged wedge-shaped layers to then determine the optimum thicknesses which yield the highest photoconversion efficiency. The device performance is locally assessed by means of light-beam induced current images. A quantitative model of co-locally measured Raman images allows determining the corresponding local thicknesses of the active layers. The spatial correlation of both datasets (i.e. local photocurrent density and active layer film thicknesses) enables the rapid optimization of the photovoltaic system studied employing a single functional device, reducing in approximately 20 times the use of resources and time., The Spanish Ministerio de Economía y Competitividad (MINECO) is gratefully acknowledged for its support through Grant No. SEV-2015-0496 in the framework of the Spanish Severo Ochoa Centre of Excellence program. J.C.-G. acknowledges funding from the MINECO through projects MAT2014-57652-C2-1-R and PCIN-2015-169-C02-01 and from the Madrid Regional Government through MAD2D project. M.A.N. acknowledges support from the MINECO through MAT2014-59315-R project. G.L. thanks the China Scholarship Council for financial support (201406790019). X.R.-M., A.S.-D. and M.C.-Q. acknowledge financial support from the European Research Council through project ERC CoG648901.

The nucleation of single macroscopic spherulites at desired positions, as well as ordered arrays of multiple spherulites, is demonstrated by combining the use of crystallizable solvents with local control of solvent evaporation during solution deposition. Moreover, the temperature assisted localized frustration of molecular orientation is shown, enabling the fabrication of samples containing both isotropic areas and spherulites. These macroscopic circular polycrystalline structures are characterized using a range of polarized spectroscopic techniques that allow quantifying their large degree of chain orientation. In order to show the potential of these large conjugated polymer spherulites centered at desired locations, graded bilayer organic photovoltaic devices were fabricated to be used as polarimeters, solid state light polarization detectors with no moving parts, and position sensitive photodetectors., The authors would like to acknowledge financial support from the Ministerio de Economía y Competitividad of Spain through the “Severo Ochoa” Programme for Centers of Excellence in R&D (SEV-2015- 0496) and projects CSD2010-00044 (Consolider NANOTHERM) and MAT2015-70850-P; CSIC through project 201560I032; and the European Research Council (ERC) under grant agreement no. 648901. The authors would like to thank Mr. Javier Fernández Tejero and Ms. Laura Córcoles Guija for their contribution toward putting together the LBIC system and Andrés Gomez for the AFM measurements. The authors are grateful to Dr. Miquel Garriga (ICMAB) and Dr. Alejandro Goñi (ICMAB) for useful discussions. The residents of Sant Pol de Mar are sincerely acknowledged for inspiration regarding a sundial that works in the shade.

The potent kinesin spindle protein inhibitor CPUYJ039 and a set of analogues were prepared by a target-oriented approach based on a Ugi reaction that uses 2-nitrophenyl isocyanides as key building blocks. The herein documented strategy provides straightforward and atom economical access to potent benzimidazole-based antimitotic agents by exploring the versatility and exploratory power of the Ugi reaction. The results of docking studies and biological activity evaluations of the benzimidazole compounds are also reported.

Zheng, Tang et al., Spectroscopic photodetection is a powerful tool in disciplines such as medical diagnosis, industrial process monitoring, or agriculture. However, its application in novel fields, including wearable and biointegrated electronics, is hampered by the use of bulky dispersive optics. Here, solution‐processed organic donor–acceptor blends are employed in a resonant optical cavity device architecture for wavelength‐tunable photodetection. While conventional photodetectors respond to above‐gap excitation, the cavity device exploits weak subgap absorption of intermolecular charge‐transfer states of the intercalating poly[2,5‐bis(3‐tetradecylthiophen‐2‐yl)thieno[3,2‐b]thiophene] (PBTTT):[6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) bimolecular crystal. This enables a highly wavelength selective, near‐infrared photoresponse with a spectral resolution down to 14 nm, as well as dark currents and detectivities comparable with commercial inorganic photodetectors. Based on this concept, a miniaturized spectrophotometer, comprising an array of narrowband cavity photodetectors, is fabricated by using a blade‐coated PBTTT:PCBM thin film with a thickness gradient. As an application example, a measurement of the transmittance spectrum of water by this device is demonstrated., The authors thank Prof. Olle Inganäs for discussions and use of his laboratory for carrying out parts of this work. This work was supported by the Alexander von Humboldt‐Foundation, through fellowships to Z.T. and Z.M., and the German Federal Ministry for Education and Research (BMBF) through the InnoProfile project “Organische p–i–n Bauelemente 2.2”. W.L. acknowledges financial support by the National Natural Science Foundation of China (Grant Nos. 51603209 and 21574138) and the Strategic Priority Research Program (XDB12030200) of the Chinese Academy of Sciences. A.M. acknowledges financial support by the Deutsche Forschungsgemeinschaft, project number LE747/53‐1. A.S.D. and M.C.Q. thank the European Research Council for financial support through grant CoG648901 and Ministerio de Economía y Competitividad of Spain through the “Severo Ochoa” Programme for Centers of Excellence in R&D (SEV‐2015‐0496) and project MAT2015‐70850‐P.

Oleate-capped CdS nanocrystals (NCs) dispersed in dichloromethane were found to quench the excited-state fluorescence of the terthiophene derivative 3′,4′-dibutyl-5″-phenyl-[2,2′:5′,2″-terthiophene]-5-carboxylic acid (1-CO2H). Infrared and 1H NMR spectroscopies provided evidence that 1-CO2H substitutes for oleate on the surface of the CdS NCs. Upon binding, the fluorescence of 1-CO2H is quenched, and the 1H NMR lines from 1-CO2H are broadened. The importance of the carboxylate group in binding to the CdS NC was further established by examining the behavior of a similar fluorophore where the carboxylic acid group was replaced with a bromo substituent (1-Br). The CdS NCs had no influence on the fluorescence intensity or NMR line shapes of 1-Br. For 1-CO2H, Stern–Volmer plots indicated a nearly linear increase in I0/I as the CdS NCs’ concentration was increased, but as the dye/NC ratio reached ∼20/1, I0/I reached a maximum of ∼8 and began to decrease. By a dye/NC ratio of 2/1, the I0/I reached a steady value...

Losses of charge carriers, due to the interfacial charge recombination processes, in small molecule organic solar cells (SMOSCs) have been investigated under operating conditions. The devices consist of zinc phthalocyanine (ZnPc) as electron donor material and C60 as electron acceptor. The results obtained by using time-resolved techniques such as charge extraction (CE) and photoinduced transient photovoltage (TPV) have been compared to the measurements carried out with impedance spectroscopy (IS) and show good agreement. Significantly, much difference is observed in either the charge density distribution versus the device voltage or the charge carriers lifetime when comparing bulk heterojunction versus bilayer-type ZnPc:C60 devices. The implications of the faster charge carrier recombination with the device fill factor (FF) and the open circuit voltage (VOC) are discussed.

A series of new poly(1-vinyl-3-alkylimidazolium) iodide polymers with different alkyl derivatives such as methyl, propyl and perflurodecyl have been synthesized. The alkyl substituent influenced some properties such as solubility, thermal stability, glass transition and crystallinity of the polymers. For instance, polymer having the propyl substituent was soluble in solvents of intermediate polarity such as acetonitrile, chloroform and THF, the one with the methyl substituent was only soluble in very polar solvents such as water and methanol and the fluorinated polymer was only soluble in DMF. The alkyl substituent also influenced the thermal stability in the order methyl > propyl > perflurodecyl and all the polymers thermally decomposed between 250 and 400 °C in nitrogen. The poly(1-vinyl-3-alkyl-imidazolium) iodide polymers having propyl and methyl substituents were amorphous polymers showing a glass transition temperature of 43 and 21 °C, respectively; and perflurodecyl polymers were semi-crystalline with a Tm at 153 °C and a Tg at 20 °C, as indicated by differential scanning calorimetry. Polymer electrolytes were formulated as mixtures of the ionic liquid 1-methyl-3-propylimidazolium iodide and the poly(1-vinyl-3-alkylimidazolium) iodide polymers. These polymer electrolytes showed ionic conductivities in the range of 10−3 to 10−7 S/cm at room temperature which strongly depended on the ionic liquid content. Finally, poly(1-vinyl-3-propyl-imidazolium) iodide was used to obtain gel electrolytes by adding it to a typical acetonitrile electrolyte used in dye sensitized solar cells (DSSCs). Solar cells with 1 cm2 area prepared using the polymer gel electrolyte yielded a maximum light-to-electricity conversion efficiency of 3.73%.

Organic solar cells made using a blend of DPM12 and P3HT are studied. The results show that higher V oc can be obtained when using DPM12 in comparison to the usual mono-substituted PCBM electron acceptor. Moreover, better device performances are also registered when the cells are irradiated with sun-simulated light of 10-50 mW cm -2 intensity. Electro-chemical and time-resolved spectroscopic measurements are compared for both devices and a 100-mV shift in the density of states (DOS) is observed for DPM12/P3HT devices with respect to PCBM/P3HT solar cells and slow polaron-recombination dynamics are found for the DPM12/P3HT devices. These observations can be directly correlated with the observed increase in V oc , which is in contrast with previous results that correlated the higher V oc with different ideatity factors obtained using dark-diode measurements. The origin for the shift in the DOS can be correlated to the crystallinity of the blend that is influenced by the properties of the included fullerene.

We report here the synthesis and characterization of a new heteroleptic ruthenium(II) complex and its applications as efficient light-harvesting sensitizer in functional dye-sensitized solar cells. The relation between the interfacial charge-transfer processes that govern the device performance and the cell efficiency under illumination are also discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Organic polymer solar cells (OPSCs) have been prepared using TiO(x) metal oxides as selective electrodes for electron collection. The interfacial charge transfer reactions, under working conditions, that limit the energy conversion efficiency of these devices have been measured and compared to the standard OPSC geometry which collects the electrons through a low work function metal contact.

We have measured the charge transfer processes on near IR small molecule solution processes solar cells under working conditions. The results show that there are two different behavior, for the device under working conditions, controlled by the intrinsic properties of the organic bulk-heterojunction phase to store charges at the different organic materials. Furthermore, our recombination kinetic studies show the origin of the photovoltage on these thin organic devices (80 nm thick) and the reason for the difference between the observed open circuit cell potential and the theoretical expected value based on the LUMOPCBM–HOMO phthalocyanine difference.

The mechanisms limiting the dark current in pentacene (Pc)/C60 solar cell were determined using the temperature dependence of the current-density-voltage characteristics. Our analysis allowed us to calculate the effective barrier height for electrons and holes at the interface. We then determined the built-in potential of the heterojunction and the effective doping concentration of the active layers, using capacitance-voltage characteristics. These physical parameters were used to simulate a band-energy diagram for a Pc/C60 solar cell in equilibrium. Finally, we determined a relation between the effective barrier height and the built-in potential.

The electron transfer reaction between the photoinjected electrons in the nanocrystalline TiO2 mesoporous sensitized films and the oxidized electrolyte in dye sensitized solar cells (DSSC) plays a major role on the device efficiency. In this communication we show that, although the presence of molecular aggregates on the free base porphyrin DSSC limits the device photocurrent response under illumination, they form an effective hydrophobic barrier against the oxidized electrolyte impeding fast back-electron transfer kinetics. Therefore, their drawback can be overcome by designing dyes with peripheral moieties that prevent the formation of the aggregates and are able to achieve efficiencies as high as 3.2% under full sun.