Microperimetric evaluation and predictive factors of visual recovery after successful inverted internal limiting membrane-flap technique for macular hole in high myopic eyes

IntroductionInverted Internal Limiting Membrane (ILM)-flap technique demonstrated its effectiveness, in terms of anatomical closure rate and visual acuity recovery for high myopic macular holes. We evaluated macular function after a successful inverted ILM-flap for macular holes in high myopic eyes (hMMH) using microperimetry to predict visual prognosis.MethodsA retrospective study on 23 eyes of 23 patients after surgical closure of hMMH, was performed. All patients underwent inverted ILM-flap and gas tamponade. Cataract surgery was performed in phakic eyes. Study outcomes including best-corrected visual acuity (BCVA), retinal sensitivity (RS) at central 12°, central retinal sensitivity (CRS) at central 4° and mean deviation (MD), and fixation behavior as bivariate contour ellipse area (BCEA, degrees2) measured by microperimetry, were evaluated over 6 months. A mixed-effects model was used to evaluate and compare the repeated measurements of outcomes between phakic and pseudophakic eyes. A regression model was performed to assess the relationship between BCVA at 6 months and independent variables.ResultsOverall mean BCVA improved from 0.98 ± 0.21 logMAR at baseline to 0.47 ± 0.31 logMAR at the last follow-up (p < 0.001). Over 6 months, overall sensitivity measurements improved (RS, p = 0.001; CRS, p < 0.0001; MD, p = 0.03), and the BCEA decreased in dimension, although not significantly (p ≥ 0.05). The mixed model revealed a significantly better effect of inverted ILM-flap combined with cataract surgery on BCVA and CRS in phakic eyes than inverted ILM-flap alone in pseudophakic ones. The regression model revealed a relationship of 6-month BCVA with pre-operative BCVA (β = 0.60, p = 0.02) and RS (β = −0.03, p = 0.01).ConclusionThe inverted ILM-flap technique significantly improved visual acuity and retinal sensitivity after the hMMH closure, particularly when combined with cataract extraction. Pre-operative visual acuity and retinal sensitivity at central 12° may predict post-surgical visual acuity

Retreatment for hepatitis C virus direct-acting antiviral therapy virological failure in primary and tertiary settings: The REACH-C cohort

Virological failure occurs in a small proportion of people treated for hepatitis C virus (HCV) with direct-acting antiviral (DAA) therapies. This study assessed retreatment for virological failure in a large real-world cohort. REACH-C is an Australian observational study (n = 10,843) evaluating treatment outcomes of sequential DAA initiations across 33 health services between March 2016 to June 2019. Virological failure retreatment data were collected until October 2020. Of 408 people with virological failure (81% male; median age 53; 38% cirrhosis; 56% genotype 3), 213 (54%) were retreated once; 15 were retreated twice. A range of genotype specific and pangenotypic DAAs were used to retreat virological failure in primary (n = 56) and tertiary (n = 157) settings. Following sofosbuvir/velpatasvir/voxilaprevir availability in 2019, the proportion retreated in primary care increased from 21% to 40% and median time to retreatment initiation declined from 294 to 152 days. Per protocol (PP) sustained virological response (SVR12) was similar for people retreated in primary and tertiary settings (80% vs 81%; p = 1.000). In regression analysis, sofosbuvir/velpatasvir/voxilaprevir (vs. other regimens) significantly decreased likelihood of second virological failure (PP SVR12 88% vs. 77%; adjusted odds ratio [AOR] 0.29; 95%CI 0.11–0.81); cirrhosis increased likelihood (PP SVR12 69% vs. 91%; AOR 4.26; 95%CI 1.64–11.09). Indigenous Australians had lower likelihood of retreatment initiation (AOR 0.36; 95%CI 0.15–0.81). Treatment setting and prescriber type were not associated with retreatment initiation or outcome. Virological failure can be effectively retreated in primary care. Expanded access to simplified retreatment regimens through decentralized models may increase retreatment uptake and reduce HCV-related mortality

Hydroxypropyl Cellulose as Enabling Material for the Nanofabrication of Photonic Architectures

La creixent preocupació per l'impacte mediambiental i la sostenibilitat de les activitats humanes ha comportat un renovat interès per l'ús de materials d'origen natural. En aquest marc, la cel·lulosa, el polímer més abundant del món, ha estat objecte d'una creixent atenció, ja que s'extrau de fonts econòmiques i renovables, essent un material extremadament versàtil ja àmpliament emprat en diferents sectors tecnològics. En aquesta tesi, s'han optimitzat els processos de nanofabricació industrialment escalables basats en tècniques de litografia suau per a la realització de estructures fotòniques en hidroxipropilcel·lulosa (HPC), un derivat de la cel·lulosa que és soluble en aigua i biocompatible. S'ilustraran les diferents estratègies per a fabricar cristalls fotònics i plasmònics en HPC emprant la litografia per nanoimpresió (NIL), una de les tècniques més prometedores per a la fabricació a gran escala de nanoestructures. Les membranes de cel·lulosa es poden modelar fàcilment en reticles periòdics de mides submicromètriques que presenten color estructural ajustable, que poden contenir tintes orgàniques per a augmentar la fotoluminiscencia d'aquestes. El recobriment metàl·lic de les arquitectures fotòniques de cel·lulosa dóna com a resultat cristalls plasmònics flexibles amb excellents propietats òptiques que es poden utilitzar com a substrats d'un sol ús per a l'espectroscopía Raman amplificada de superfície. Una ruta alternativa per integrar materials funcionals a l'HPC es mitjançant la tècnica d'impressió per transferència, una estratègia de nanofabricació que proporciona una manera senzilla per a l'ensamblatge de materials processats independentment en arquitectures més complexes. S'aprofunditza en la gran versatilitat d'aquesta tècnica incorporant xarxes ordenades de nanopartícules metàl·liques y matrius de nanotubs de carboni en películ·les adhesives d'HPC, obtenint respectivament superestructures multicapa de tipus Moirè i electrodes conductors semitransparents. Així mateix, els adhesius HPC també poden funcionar con cintes transitòries per a transferir el material des d'un substrant donant a un de receptor de manera ecològica. Les cintes d'HPC s'adhereixen perfectament a substrats irregulars i es poden treure amb un senzill rentat d'aigua. Específicament, es demostra una millora del rendiment de la transferència utilitzant aquest mètode respecte a un d'estàndard basat en elastòmers, demostrant l'absència d'aparició d'escletxes durant el despreniment així com la transferència i apilament de pel·lícules metàl·liques fines, tant contínues com amb patrons. Seguint amb la idea de reduïr la contaminació química en els processos de nanofabricació, s'empra l'HPC com a material transitori no tòxic i processable amb aigua per a la nanofabricació avançada i ecològica en combinació amb la tècnica NIL. L'HPC mostra una resistència excel·lent quan és utilitzada en processos de fabricació electrònics estàndard, com el gravat amb ions reactius i la deposició i llevament de metalls. Nanoestructures de silici amb mides de fins un mínim de 100nm i xarxes de nanopartícules es fabriquen de manera senzilla emprant solament HPC i aigua com a dissolvent.La creciente preocupación por el impacto medioambiental y la sostenibilidad de las actividades humanas ha llevado a un renovado interés para los materiales de origen natural. En este marco, la celulosa, el polímero natural más abundante del mundo, ha recibido una gran atención. La celulosa se extrae de fuentes baratas y renovables y es un material extremamente versátil y ya ampliamente empleado en diferentes sectores tecnológicos. En esta tesis, se han optimizado procesos de nanofabricación escalables y compatibles con la industria empleando la técnica de litografía suave, para la fabricación de arquitecturas fotónicas en hidroxipropilcelulosa (HPC). La HPC es un derivado de celulosa que es soluble en agua y biocompatible. En la tesis se ilustrarán las diferentes estrategias adoptadas para fabricar cristales fotónicos y plasmónicos en HPC utilizando la litografía por nanoimpresión (NIL), una de las técnicas más prometedoras para la fabricación a gran escala de nanoestructuras. Las membranas de celulosa se pueden imprimir fácilmente con motivos periódicos de tamaño submicrométrico, dando como resultado colores estructurales, además la celulosa puede hospedar colorantes orgánicos y mediante la corrugación aumentar su fotoluminiscencia. El recubrimiento metálico de estas arquitecturas fotónicas de celulosa da como resultado cristales plasmónicos flexibles con excelentes propiedades ópticas que se pueden utilizar como sustratos desechables para espectroscopía Raman amplificada en superficie. En esta tesis también se incluye el estudio de una ruta alternativa para integrar materiales funcionales en la HPC mediante la técnica de impresión por transferencia. Esta estrategia de nanofabricación proporciona una manera sencilla para ensamblar materiales que han sido procesados independientemente combinándolos en arquitecturas más complejas. Además, se demuestra la gran versatilidad de esta técnica fabricando redes ordenadas de nanopartículas metálicas y matrices de nanotubos de carbono soportadas en películas adhesivas de HPC, obteniendo respectivamente superestructuras tipo Moiré y electrodos conductores semitransparentes. Las membranas de HPC también pueden funcionar como cintas adhesivas solubles en agua empleadas para transferir material de un sustrato donante a uno receptor de manera respetuosa con el medio ambiente. Las cintas de HPC se adhieren perfectamente a sustratos irregulares y se pueden eliminar con agua. Específicamente, se demuestra una mejora en la trasferencia de membranas de metal utilizando este método respecto al procedimiento estándar que emplea siliconas. La transferencia con HPC previene la aparición de grietas durante el proceso de transferencia y permite el apilamiento de películas metálicas finas, tanto con patrón como continuas. Por último y siguiendo la idea de reducir la contaminación derivada de los procesos de nanofabricación, se emplea la HPC como resina transitoria no tóxica y procesable con agua para su empleo en técnicas de nanofabricación avanzada y ecológica como la técnica NIL. La HPC ha demostrado una resistencia y compatibilidad excelente al emplearse en procesos de nanofabricación estándar, como el grabado con iones reactivos o la deposición de máscaras de metal. Empleando HPC como resina, se han producido nanoestructuras de silicio con tamaños mínimos de hasta 100 nm, también se han conseguido fabricar redes de nanopartículas metálicas de manera sencilla empleando solo HPC y agua como disolvente.The increasing concerns about environmental impact and sustainability of human activities have led to a renewed interest in naturally derived materials. In this frame, cellulose, the most abundant polymer on earth, has attracted increasing attention, since it is extracted from cheap and renewable sources, it is extremely versatile and already widely employed in different technological sectors. In this thesis, I optimized industrially scalable nanofabrication processes based on soft-lithographic techniques, for the realization of tailored photonic architectures in hydroxypropyl cellulose (HPC), a water soluble and biocompatible cellulose derivative. I illustrate different strategies to fabricate photonic and plasmonic crystal into HPC using nanoimprint lithography (NIL), one of the most promising techniques for large-scale manufacturing. Cellulose membranes can be easily patterned into submicrometric periodic lattices that exhibit tunable structural colors, can host an organic dye and boost its photoluminescence. Metal coating these cellulose photonic architectures results in flexible plasmonic crystals with excellent optical properties that can be used as disposable surface-enhanced Raman spectroscopy substrates. An alternative route to integrate functional materials into HPC is by transfer printing technique, a nanofabrication strategy that provides a straightforward way for the assembly of independently processed materials into spatially tailored architectures. I explore the high versatility of this approach embedding metal nanoparticles arrays and carbon nanotube networks into HPC adhesive films, obtaining respectively Moiré multilayer superstructures and semitransparent conducting electrodes. Interestingly, the HPC adhesives can also work as transient tapes for transferring material from a donor substrate to a receiver one, in an ecofriendly fashion. HPC tapes adhere perfectly to uneven substrates and can be simply washed away using water. Specifically, I demonstrate improved performance of this method compared to standard transfer based on elastomers, showing crack free stripping, transfer and piling up of both patterned and continuous thin metallic films. Following the line of reducing chemical pollution in nanofabrication processes, I employed HPC as non-toxic and water processable sacrificial material for advanced and ecofriendly nanofabrication aided by NIL. HPC showed excellent performance when employed as resist under standard electronic manufacturing processes, such as reactive ion etching and metal lift off. Silicon nanostructures with feature sizes down to 100 nm and metal nanoparticle arrays are straightforwardly fabricated employing just HPC and water as solvent

A water-processable cellulose-based resist for advanced nanofabrication

The ideal nanofabrication technique is one that allows the mass production of high resolution submicrometric features in a cost efficient and environmentally friendly fashion. A great step towards achieving this goal has been the development of nanoimprinting lithography, a procedure with tenths of nanometres resolution while being compatible with roll-to-roll manufacturing. However, an ecofriendly resist that can be efficiently combined with this process is still missing. In this work, we demonstrate the use of hydroxypropyl cellulose (HPC) as a biocompatible, biodegradable, and water processable resist for temperature assisted nanoimprint lithography (tNIL) by fabricating different photonic architectures. The cellulose derivative is easily patterned with submicrometric features with aspect ratios greater than 1 using an elastomeric stamp and a hot plate. Silicon photonic crystals and metal nanoparticle arrays are fabricated combining cellulose with traditional nanofrabrication processes such as spincasting, reactive ion etching and metal lift off. Furthermore, advanced nanofabrication possibilities are within reach by combining the HPC with traditional resists. In particular, poly(methyl methacrylate) and HPC stacks are easily produced by liquid phase processing, where one of the two materials can be selectively removed by developing in orthogonal solvents. This capability becomes even more interesting by including nanoimprinted layers in the stack, leading to the encapsulation of arrays of air features in the resist.The Spanish Ministerio de Economía, Industria y Competitividad (MINECO) is gratefully acknowledged for its support through Grant No. MAT2016-79053-P and through Grant No. SEV-2015-0496 in the framework of the Spanish Severo Ochoa Centre of Excellence program. AM was funded by a Ramón y Cajal fellowship (RYC-2014-16444). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Grant Agreement No. 637116, ENLIGHTMENT). The authors would like to acknowledge M. Simón and A. Gómez for AFM measurements.Peer reviewe

High Resolution Millimeter Wave Absorption Spectroscopy: from the laboratory data to the astronomical surveys

Conventional absorption spectroscopy is still the workhorse in high-resolution rotational laboratory spectroscopy.1 The data obtained from these kind of instruments are relevant for astronomical searches of complex molecules that represent excellent probes of the physical and chemical environments and history of the sources where they are detected.2 Nowadays, observations performed by the Atacama Large Millimeter Array (ALMA) open up new opportunities to reveal the chemical complexity of solar systems analogues. At the same time the huge amount of data collected and the extremely rich surveys represent a challenge for the astrochemistry community. To reach this goal, the spectroscopic know-how is fundamental in recognizing typical pattern lines due to multiple internal interactions and motions that cause complicated energy level schemes, since the resulting spectra will be rather difficult to predict theoretically, mainly in the sub-mm wave region. For this reason a strong interplay between laboratory spectroscopists and observational astronomers is increasingly required to be able to unravel the experimental data. In this talk the features and the potential of the high resolution rotational spectroscopy technique will be pointed out, providing some results on different kind of molecules characterized by complex conformational landscapes. In particular, molecular spectra of potential astronomical interest will be presented, obtained using the free jet absorption millimeter wave and the free space cell absorption sub-mm wave spectrometers working at University of Bologna.3 References [1] S. Br\ufcnken, S. Schlemmer, arXiv:1605.07456, 2016 [2] E. Herbst, E. F. van Dishoeck, Annu. Rev. Astron. Astrophys. 47, 427, 2009 [3] C. Calabrese, A. Maris, L. Evangelisti, L. B. Favero, S. Melandri, W. Caminati, J. Phys. Chem. A. 117, 13712, 201

Hydroxypropyl Cellulose Adhesives for Transfer Printing of Carbon Nanotubes and Metallic Nanostructures

Transfer printing is one of the key nanofabrication techniques for the large‐scale manufacturing of complex device architectures. It provides a cost‐effective and high‐throughput route for the integration of independently processed materials into spatially tailored architectures. Furthermore, this method enables the fabrication of flexible and curvilinear devices, paving the way for the fabrication of a new generation of technologies for optics, electronics, and biomedicine. In this work, hydroxypropyl cellulose (HPC) membranes are used as water soluble adhesives for transfer printing processes with improved performance and versatility compared to conventional silicone alternatives. The high‐water solubility and excellent mechanical properties of HPC facilitate transfer printing with high yield for both metal and carbon nanotubes (CNTs) inks. In the case of metal inks, crack‐free stripping of silver films and the simple fabrication of Moiré Plasmonic architectures of different geometries are demonstrated. Furthermore, HPC membranes are used to transfer print carbon nanotube films with different thicknesses and up to 77% transparency in the visible and near infrared region with potential applications as transparent conductive substrates. Finally, the use of prepatterned HPC membranes enables nanoscale patterning of CNT with feature resolution down to 1 µm.This project received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant Agreement No. 637116, ENLIGHTMENT and No. 648901) and the Generalitat de Catalunya program AGAUR 2017‐SGR‐00488. The Spanish Ministerio de Ciencia e Innovación is gratefully acknowledged for its support through Grant Nos. PGC2018‐095411‐B‐I00, PID2019‐106860GB‐I00, and SEV‐2015‐0496, in the framework of the Spanish Severo Ochoa Centre of Excellence program. This work was done in the framework of the doctorate in Materials Science of the Autonomous University of Barcelona.Peer reviewe

Facile Chemical Route to Prepare Water Soluble Epitaxial Sr3Al2O6 Sacrificial Layers for Free‐Standing Oxides

The growth of epitaxial complex oxides has been essentially limited to specific substrates that can induce epitaxial growth and stand high temperature thermal treatments. These restrictions hinder the opportunity to manipulate and integrate such materials into new artificial heterostructures including the use of polymeric and silicon substrates and study emergent phenomena for novel applications. To tackle this bottleneck, herein, a facile chemical route to prepare water‐soluble epitaxial Sr3Al2O6 thin films to be used as sacrificial layer for future free‐standing epitaxial complex oxide manipulation is described. Two solution processes are put forward based on metal nitrate and metalorganic precursors to prepare dense, homogeneous and epitaxial Sr3Al2O6 thin films that can be easily etched by milli‐Q water. Moreover, as a proof of concept, a basic heterostructure consisting of Al2O3/Sr3Al2O6 on SrTiO3 is fabricated to subsequently exfoliate the Al2O3 thin film and transfer it to a polymer substrate. This is a robust chemical and low‐cost methodology that could be adopted to prepare a wide variety of thin films to fabricate artificial heterostructures to go beyond the traditional electronic, spintronic, and energy storage and conversion devices.This research was supported by the Spanish Ministerio de Ciencia, Innovación y Universidades (“Severo Ochoa” Programme for Centres of Excellence in R&D FUNFUTURE CEX2019‐000917‐S and MAT2017‐83169‐R(AEI/FEDER, EU)). The project that gave rise to these results received the support of a fellowship from “la Caixa” Foundation LCF/BQ/DI19/11730026. M.C. acknowledges Becas Leonardo fundación BBVA. I.C. acknowledges the JAE Intro fellowship, JAEINT1901918. This work was done in the framework of the doctorate in material science of the Autonomous University of Barcelona. This work received financial support from the National Key R&D Program of China (2018YFA0305800), and the Beijing Outstanding Young Scientist Program (BJJWZYJH01201914430039).Peer reviewe

Structural and Optical Properties of Novel Nanoimprinted Photonic Architectures

Nanoscale fabrication methods with high resolution and yielding large area patterns have been a prominent research area in recent years due to their crucial role in the implementation of nanosized devices for various applications. Soft nanoimprinting lithography is an easy and scalable fabrication technique that allows seamless integration of photonic nanostructures in many optoelectronic fabrication procedures. In this talk, we focus on the fabrication of photonic architectures using soft nanoimprinting and their exciting optical properties with applications in light harvesting and sensing. The method can be applied to a wide choice of materials. For example, we have built a superabsorber semiconductor metasurface based on Au/Ge extending from the visible to the Ge bandgap in the near infrared range. This enhanced optical absorption stems from the strong interplay between Brewster modes, sustained by the judiciously nanostructured thin semiconductor on metal film, and photonic crystal modes. In this architecture, we demonstrate near-unity absorption which is robust upon angle of incidence variation. A different choice are cellulose-related materials. The fabrication of photonic and plasmonic structures by moulding cellulose into sub-micrometric periodic lattices using soft lithography is an alternative way to achieve structural colour. The biocompatible cellulose membranes exhibit tuneable colours and may be used to boost the photoluminescence of a host organic dye. Furthermore, we show how metal coating these cellulose photonic architectures leads to plasmonic crystals acting as disposable surface enhanced Raman spectroscopy substrates