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Background and aims: Acquired Neuromyotonia (NMT) is an autoimmune condition frequently associated with anti-contactin-associated-protein-like-2 (Caspr2) antibodies. NMT can occur as a paraneoplastic disorder in patients with thymoma, alone or in combination with Myasthenia Gravis (MG). Recently, antibodies against netrin-1-receptors (DCC and UNC5A) have been reported as predictors of thymoma in 6/9 patients with concomitant NMT and MG. We aimed to clinically characterize a large cohort of patients with thymoma-associated MG, and to explore serological correlation of NMT symptoms. Methods: 268 consecutive patients with thymoma-associated MG were retrospectively collected. NMT was defined as muscle twitching/cramps in at least 2 skeletal districts. Patients with NMT(23) were screened for anti-neuronal antibodies by immunohistochemistry on rat brain and cell based assay. Results: 23/268 patients developed NMT symptoms (muscle twitching, 3; cramps, 3, or both, 17). Overall, 33/268 patients with thymoma had a tumor recurrence, which was more frequent in those with (8/23) vs those without NMT (25/245, p=0.003). NMT onset preceded the tumor recurrence in 5/6 patients. In univariate analysis predictors of thymoma recurrence were younger age at thymectomy (odds ratio-OR:0.95, confidence interval-CI:0.93-0.97), Masaoka staging (OR:10.73, CI:2.38-48.36) and NMT (OR:4.69, CI:1.76-12.46). 6 patients with NMT had anti-neuronal antibodies (patient#1: Caspr2; patient#2: AMPAR; patient#3: DCC; patient#4: LGI1; patient#5: Caspr2+LGI1+DCC+UNC5A; patient#6: Caspr2+LGI1+DCC). Thymoma recurrence was found less frequently in negative (3/17) vs positive patients with NMT (4/6, #1, #2, #5 and #6; p=0.045). Conclusion: The occurrence of NMT symptoms in patients with thymoma-associated MG can predict tumor recurrence, and warrants a closer oncologic follow-up. Anti-neuronal surface autoantibodies may be useful to further stratify the recurrence risk. Disclosure: This work was funded by the ‘Ricerca finalizzata ministeriale 2015-2017’ provided by the Italian ministry of health

In this work, we compared the photovoltaic performance of standard and inverted polymer solar cells with the aim to elucidate the origin of the different current output. We realized devices with both architectures using a blend film of poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b:4,5-b′]dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiopene)-2,6-diyl] /[6,6]-phenyl C71 butyric acid methyl ester (PBDTTT-C:[70]PCBM). The standard cell sequence is ITO/PEDOT:PSS/PBDTTT-C:[70]PCBM/Ca/Al and the inverted one is ITO/ZnO/PBDTTT-C:[70]PCBM/MoO3/Ag. The inverted architecture shows better performances compared to the standard one mainly in terms of current output. The optical modeling has revealed that this architecture allows more photons to be absorbed in the blend film, giving rise to an higher current output, although the observed improvement cannot be completely attributed to the calculated higher absorption of the incoming light. By using the impedance spectroscopy analysis, we found that the inverted device architecture has higher values for the interface trap time constant and the density of interface states. Both parameters contribute to retain the charge collection efficient, compared to the standard configuration, despite the increased charge carrier density and to further improve the current output. © 2016 Elsevier B.V. All rights reserved.

Substoichiometric molybdenum oxide (MoOx) has good potential as a hole-collecting layer in solar cells. In this paper, we report on the application of ultrathin evaporated MoOx as a hole collector at the back side of two distinct photovoltaic technologies: polymeric and silicon heterojunction (SHJ). In the case of polymer solar cells, we test MoOx as a hole transport layer in devices with inverted architecture. The higher transparency of the MoOx film, compared to the commonly used poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), allows an enhanced back reflected light into the photoactive layer, thus boosting the photogeneration, as found from the illuminated J-V and external quantum efficiency (EQE) curves. The higher fill factor (FF) of the MoOx-based device also suggests an improved charge collection efficiency compared to the cells with PEDOT:PSS. As for SHJ solar cells, we show that MoOx offers the means for dopant-free hole collection with both p-type and n-type Si wafers. In the present comparison over planar test structures with Ag back reflecting electrodes, we observe an efficiency gain of approximately 1% absolute against a baseline with a conventional p-type amorphous silicon hole collector. The gain is linked to the increased VOC, which is likely due to the reduced recombination at the Si wafer.

In this work we improved the performance of ITO-free polymer solar cells (PSCs) by incorporating silver nanoparticles (AgNPs) in the highly conductive (HC) PEDOT:PSS anode. The AgNPs were synthetized in-situ in the PEDOT:PSS water dispersion. This anode was used to realize PSCs with the following geometry: glass/HC-PEDOT:PSS/PEDOT:PSS/PBDTTT-C:[70]PCBM/Ca/Al. All the devices were characterized by UV-VIS spectroscopy, impedance spectroscopy, IV light, IV dark and quantum efficiency measurements. The presence of AgNPs in the HC-PEDOT:PSS anode contributes to improve the absorption of the photoactive layer and to lower the resistivity of the anode.

The performances and the stability of a polymer solar cell (PSC) mainly depend on the architecture of the device and the materials used for the fabrication (photoactive and interface layers and contacts). In this work we made a comparative study between standard and inverted PSCs having an identical pair of hole and electron transport layers: molybdenum trioxide (MoO3) and poly[(9,9-bis(3'-(N,Ndimethylamino) propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN), respectively. We realized devices using a blend film of poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b;4,5-b']dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiopene)-2,6-diyl]/[6,6]-phenyl C71 butyric acid methyl ester (PBDTTT-C:[70]PCBM). The standard and inverted cells sequences were ITO/MoO3/PBDTTT-C:[70]PCBM/PFN/Ag and ITO/PFN/PBDTTT-C:[70]PCBM/MoO3/Ag, respectively. We studied the performances of both kinds of devices in order to investigate the influence of the architecture (standard vs inverted) on the performance of the solar cells. All the devices were characterized by IV light, IV dark and quantum efficiency measurements. The best device reached a power conversion efficiency of 6%. The inverted device has an improved current output compared to the standard one. In order to elucidate the absorption of photons inside the blend, we performed the optical modeling of the devices using the transfer matrix formalism and we simulated the effective absorption in the photoactive layer and the optical electric field inside the devices.

The structural organization of matter in poly(vinyl alcohol) (PVA) hydrogels obtained by repeatedly freezing and thawing dilute solutions of PVA in D2O is investigated by use of small-angle neutron scattering measurements (SANS). This study is the first systematic and quantitative investigation in the medium range of length scales on PVA hydrogels obtained by freezing and thawing techniques. The studied gels have a complex hierarchical structure, extending over a wide range of length scales. The structural organization on the micron length scale originates from the presence of two separated phases constituted by polymer-rich and polymer-poor regions. The network structure may be interpreted in terms of the connectivity of the regions occupied by the polymer-rich phase, which extend over the macroscopic dimensions of the sample. The organization on the medium length scale is provided by the presence of small crystallites, fringed micelle-like, within the polymer-rich phase. In these regions, the crystals are highly connected by swollen amorphous tie chains. The presence of these tie chains ensures the connectivity of the macroscopic network. The structural organization on the short length scale is essentially provided by the relative arrangement of chains within the crystallites and in the swollen amorphous zones. The PVA hydrogel structure has been modeled as a collection of polydisperse and homogeneous spherical crystallites, interacting via hard-spheres potential. SANS experiments permitted us to obtain values of the crystallite size of about 33 Angstrom, of the volume fraction of polymer-rich phase of the order of 1% and a value of the average crystallite-crystallite correlation distances of the order of a few tens of nanometers, independent of the imposed number of freeze/thaw cycles (n), for n > 1. The present analysis also indicates that the structure of the gel obtained imposing a single freeze/thaw cycle is somehow intermediate between the structure of the homogeneous starting solution and the structure of the already well-formed sample obtained by imposing two consecutive cycles.

In this work, highly conductive and transparent films based on poly(3,4 ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) doped with dimethyl sulfoxide (DMSO) were printed onto a flexible substrate, the polyethylene naphthalate (PEN), using the gravure printing method. Gravure-printed DMSO-PEDOT:PSS ink suitably modified with isopropanol was developed and used as anode in flexible solar cells replacing the commonly used anode, that is, Indium Tin Oxide (ITO). Several inks were prepared and characterized in terms of viscosity and surface energy and tested by gravure printing. The wettability of the PEN substrate was investigated through contact angle measurements. For comparison, the anodic conductive polymer was also spin coated on the PEN substrate using an ink suitable for this technique. The films produced with both the techniques, gravure printing and spin coating, each using a proper ink, were characterized in terms of structure and physical–chemical properties. The printed layers were employed as anodes into ITO free-polymer solar cells based on a bulk heterojunction of Poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno [3,4-b]thiophenediyl}) (PTB7) and [6,6]-phenyl C70-butyric acid methyl ester ([70]PCBM). The performances of the devices with printed and spin coated polymeric anode were compared. The cell with the spin-coated anode reached a power conversion efficiency of 3% while the corresponding device with the printed anode a value around 2%. POLYM. COMPOS., 36:1104–1109, 2015. © 2015 Society of Plastics Engineers

In this work, we report the application of a sol–gel derived ZnO thin film as a buffer layer for high efficiency inverted polymer solar cells. ZnO films are widely used in such devices because they have a relatively high electron mobility, high transparency and environmental stability. The ZnO precursor was prepared by dissolving zinc acetate and ethanolamine in the 2-methoxyethanol. ZnO thin films were then deposited on indium tin oxide (ITO)/glass substrates by spin coating the above solution. Inverted polymer solar cells with the configuration ITO/ZnO/photoactive layer/MoOx/Ag were realized in order to investigate the performance of ZnO thin film. The photoactive layer is a blend of poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b;4,5-b′]dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiophene)-2,6-diyl] (PBDTTT-C) and [6,6]-phenyl C71 butyric acid methyl ester ([70]PCBM) (1:1.5 w/w). We made a comparative study of the photovoltaic behavior of devices with ZnO films deposited using different sol–gel recipes. In particular, we varied the zinc acetate/ethanolamine molar ratio to have ZnO films with different trace amounts of starting materials. In addition we also prepared ZnO films annealed at 200 °C for different times (from 5′ to 60′) in order to evaluate this effect on the trace amount removal. © 2014, Springer Science+Business Media New York.

In this work we studied the influence of the annealing treatments of a sol-gel derived ZnO electron transport layer deposited on ITO substrate, on the performances of inverted bulk heterojunction polymer solar cells using a blend of poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b;4,5-b′]dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiopene)-2,6-diyl] and [6,6]-phenyl C71 butyric acid methyl ester. Since the annealing treatments needed to complete the formation of the solution-processed ZnO film can modify the underlying ITO electrode, we analyzed the performance of the fabricated cells in terms of the properties of ITO and ZnO films. We found a linear relationship between the sheet resistance of the ITO layer and the series resistance of the corresponding device, which strongly influences the fill factor. The best power conversion efficiency (7%) under simulated AM 1.5G illumination of 100 mW/cm2 was achieved for the polymer solar cell fabricated using a ZnO film annealed at 150 °C for only 5 min. Higher annealing temperatures and times increase the sheet resistance of the ITO worsening the device performances. © 2015 Elsevier B.V. All ights reserved.

In this work we made a comparative study between the electrical performances of three different electron transport layers (ETLs), used to build inverted polymer solar cells (PSCs). Two different metal oxides are prepared with a solution process: the first one is zinc oxide, prepared by a solgel procedure dissolving zinc acetate and ethanolamine in the 2-methoxyethanol, the second one is titanium oxide, prepared by spin coating a solution of commercial Titanium(IV)-isoproxide in 2-methoxyethanol. The last ETL is an alcohol soluble conjugated polymer: poly[(9,9-bis(3′-(N, N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)](PFN). Inverted PSCs with the configuration glass/ITO/ETL/photoactive layer/MoO3/Ag were realized in order to investigate the performance of different ETL thin films. The photoactive layer was a blend of poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b;4,5-b′] dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiopene)-2,6-diyl] and [6,6]-phenyl C71 butyric acid methyl ester. The best power conversion efficiency (6.4%) under simulated AM1.5G illumination of 100 mW/cm2, was achieved for the PSCs fabricated using a ZnO and PFN films.

Indium tin oxide (ITO) is the most common transparent anode for polymer solar cells (PSCs). The limited flexibility of ITO, the increasing cost of indium and the patterning of ITO with a lot of chemicals, make this material not desirable for the realization of flexible, low-cost and efficient PSCs. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has been investigated as innovative polymeric material for replacing ITO due to its high transparency, long-term stability and solution process ability. In this work we realized ITO-free polymer solar cells having as active layer a poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b;4,5-b′]dithiophene)-2, 6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiopene)-2,6-diyl] / [6,6]-phenyl C71 butyric acid methyl ester (PBDTTT-C/[70]PCBM) blend film. The anode was realized using a highly conductive (HC) PEDOT:PSS layer. We studied the performances of this device by means of IV-dark, IV-light, external quantum efficiency and impedance spectroscopy measurements. The performance of the ITO-free device was compared with the corresponding one built using a standard ITO anode. © 2014 AEIT.

The architecture of a polymer solar cell plays a crucial role on its stability because some of the materials used to build the device can suffer from degradation when exposed to air and/or oxygen. In this work we made a comparative study between the standard and the inverted polymer solar cells based on the bulk-heterojunction structure. We realized standard and inverted polymer solar cells using a blend film of poly[(4,8-bis-(2-ethylhexyloxy)- benzo[1,2-b;4,5-b′]dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl) -thieno[3,4-b]thiopene)-2,6-diyl] / [6,6]-phenyl C71 butyric acid methyl ester (PBDTTT-C:[70]PCBM) blend films. In the standard architecture, the transparent indium tin oxide (ITO) electrode is coated with poly-(3,4- ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) and used as a hole collecting electrode, while in an inverted device configuration, the ITO electrode is turned into the electron collecting contact by surface modification with zinc oxide (ZnO). The standard cells sequence is ITO/PEDOT:PSS/PBDTTT-C: [70]PCBM/Ca/Al and the inverted cells one is ITO/ZnO/PBDTTT-C:[70]PCBM/MoO 3/Ag. We studied the electrical behavior (by means of IV-dark and IV-light at different illumination levels and external quantum efficiency measurements) of both kinds of devices in order to investigate the influence of the architecture (standard vs inverted) on the performance of the solar cells. © 2014 AEIT.

In this paper we present the synthesis and characterization of two novel copolymers obtained from a bithiophene unit carrying octylsulfanyl side chains and thienothiophene units substituted with keto (PK) or ester (PE) groups. Their structural, electrochemical and photophysical properties were investigated by gel permeation chromatography (GPC), thermogravimetric analysis (TGA), NMR, UV-visible-NIR spectroscopy, cyclic voltammetry (CV) and atomic force microscopy (AFM). They possess good solubility in common organic solvents, filmability, proneness to form π-stacks, moderate solvatochromism, good thermal stability and low band gap energy. They were tested as donor materials in combination with [70]PCBM (electron acceptor) in bulk-heterojunction polymer solar cells. The geometry of the devices is: glass/ITO/PEDOT:PSS/copolymer:[70]PCBM/Ca/Al. The external quantum efficiency curve of the best device, realized using a blend of PK : [70]PCBM, 1 : 2 weight ratio, shows a broad response from 350 to 1000 nm. The power conversion efficiency under 100 mW cm-2 AM 1.5G illumination is greater than 1%. © 2014 The Royal Society of Chemistry.

In this work, highly conductive anode based on PEDOT:PSS is proposed as substitute of Indio-Tin Oxide (ITO) in flexible solar cells. The anodic conductive polymer was spin coated on a 125 μm thick polyethylene naphthalate (PEN) substrate. The obtained film was characterized in terms of structure and physical- chemical proprieties. The obtained results are very promising and the conductive film will be investigated in future as electrode in a complete polymeric solar cell. © 2014 AIP Publishing LLC.

The structure of poly(vinyl alcohol) (PVA) hydrogels formed as a result of freeze/thaw treatments of aqueous solutions of the polymer (11 wt % PVA) in the freshly prepared state is analyzed through the combined use of small (SANS) and ultrasmall (USANS) angle neutron scattering techniques. The structure of these hydrogels may be described in terms of polymer rich regions, with dimensions of the order of 1-2 microm, dispersed in a water rich phase, forming two bicontinuous phases. The PVA chains in the polymer rich phase form a network where the cross-linking points are mainly crystalline aggregates of PVA having average dimensions of approximately 45 A. The structural organization of freeze/thaw PVA hydrogel membranes does not change either after rehydration of dried gels or in the presence of a tensile force. Finally, addition of surfactant micelles inside the gel provides a formulation with both hydrophobic and hydrophilic regions, which demonstrates the potential of the system for drug delivery. Both SANS and EPR measurements show that sodium decylsulfate (C10OS) micelles do not significantly interact with the PVA gel. Variation of the gel structure by the number of freeze/thaw cycles should modulate the rate of release of an active constituent, for example, in a dermal patch.

UID/LIN/03213/2013 PD/BD/113974/2015 A presente comunicação mostra nossas análises do gênero de texto graffiti, como parte dotrabalho realizado pela equipe de pesquisa que reúne colegas de Rosário, Córdoba e Lisboa, eatualmente desenvolve o projeto “Análisis de géneros textuales, enseñanza de lenguas ytraducción (portugués/español)” que propõe a análise interlinguística de gêneros textuais comobjetivo de criar ferramentas de consulta para professores, pesquisadores e tradutores.Acreditamos que o graffiti, como gênero de texto, existente desde a Antiguidade (Kozak, 2008),revela as tensões e relações de poder próprias de complexos processos de conformação de umadeterminada sociedade, sendo instrumentos linguísticos e culturais privilegiados para seremlevados à sala de aula de português como língua estrangeira. Partindo do pressuposto de quediferentes contextos discursivos geram práticas linguísticas diferenciadas (Rosa, Ricciardi &Gonçalves, 2018; Rosa, 2018) e assumindo que o português é uma língua pluricéntrica queapresenta mais do que uma variedade, propomos analisar o graffiti nas variedades europeia (PE)e brasileira (PB), entendendo que cada uma irá revelar processos históricos e culturais própriosde cada contexto geográfico e social. Para tal, privilegiamos uma abordagem descendente(Voloshinov, [1929] 2009) e contrastiva, com o fim de apresentar elementos para um “modelodidático do gênero” (De Pietro et al, 1996; Schneuwly, 2003), entendido como dispositivoteórico de descrição das características do género, tendo em vista seu ensino. Concebemos ogênero, segundo a perspectiva do Interacionismo Sociodiscursivo, como um modelocomunicativo, constructo histórico, produto de interações sociais que apresenta singularidadesdecorrentes do contexto em que este é mobilizado (Bronckart, [1997] 1999; 2003). Adotando osinstrumentos de análise deste quadro teórico metodológico (modelo de ação de linguagem emodelo da arquitetura textual), será proposta uma descrição do gênero graffiti, considerando agrande maleabilidade que lhe é inerente, analisando os contextos físicos e sociossubjetivos deprodução, tendo em conta características específicas dos espaços urbanos do Brasil e dePortugal, as singularidades do plano do texto, os tipos discursivos e os mecanismos detextualização e de responsabilização enunciativa (Bronckart, [1997] 1999; 2003). A partir daanálise efetuada, apresentamos as dimensões ensináveis do graffiti, entendendo que essasreflexões em torno do gênero representam um instrumento de ensino para aqueles que atuam naárea de formação de professores, pesquisadores e tradutores.Palavras-chave: graffiti, modelo didático, português língua estrangeira, análise contrastiva. publishersversion published