Printable organic and inorganic materials for flexible electrochemical devices

Portuguese Science Foundation - project Electra PTDC/CTM/099124/2008 and the PhD grant SFRH/BD/45224. financial support: Professor E. Fortunato’s ERC 2008 Advanced Grant (INVISIBLE contract number 228144), “APPLE” FP7-NMP-2010-SME/262782-2 and “SMARTEC” FP7-ICT-2009.3.9/25820

Search and information extraction in handwritten tables

[ES] Actualmente, archivos de todo el mundo están digitalizando grandes colecciones de documentos manuscritos con el fin de preservarlos y facilitar su difusión a investigadores y usuarios generales. Este hecho está motivando una gran evolución en las técnicas de reconocimiento de texto manuscrito (HTR por sus siglas en inglés), que permiten acceder a los contenidos textuales de las imágenes digitales mediante consultas de texto plano, de la misma manera que se hace con los libros y otros documentos digitales. Dentro del conjunto de documentos manuscritos sin transcripción, nos encontramos con que aproximadamente más de la mitad de los documentos se corresponden con documentos estructurados. Estos documentos contienen información de todo tipo: registros de nacimiento, de navegación, cuadernos de bitácora, etc. Toda esta información es a menudo imprescindible para usos jurídicos, estudios demográficos, estudios de la evolución del clima, etc. El objetivo de este trabajo es desarrollar nuevos métodos que permitan realizar búsquedas según el modelo "atributo-valor'" sobre estos documentos, donde los "atributos" son las cabeceras de las columnas y filas que forman la tabla y los "valores" son el resto de celdas de la tabla que no son cabecera. Para ello, vamos a basarnos en el marco de la indexación probabilistica (que está en cierto modo relacionado con el campo conocido como "keyword spotting"). En este marco, cada elemento de una imagen que se pueda interpretar como una palabra es detectado y almacenado, junto con su posición dentro de la imagen y la correspondiente probabilidad de relevancia. Así pues, empleando la información geométrica de los índices probabilísticos en conjunto con el uso de distribuciones gausianas, se pretende permitir realizar este tipo de búsquedas desde una perspectiva completamente probabilística. Bajo este enfoque, además de la búsqueda, se estudia la extracción de la información con objetivo de volcar contenidos específicos de las imágenes digitales a un formato compatible con bases de datos convencionales. En ambas tareas se han logrado resultados que superan el baseline propuesto.[EN] Currently, all archives around the world are digitising large collections of manuscripts, aiming to preserve and facilitate their dissemination to researchers and general users. This fact is motivating a fast evolution in handwritten text recognition (HTR) techniques, which allow accessing to the textual contents of digital images by means of plain-text queries, in the same way as with books and other digital documents. Among the huge set of manuscripts without transcription, more than half of the documents contain structured text. This is the case of birth records, navigation logs, etc. The information contained in these documents is often needed for legal matters, demographic studies, weather evolution studies, etc. The purpose of this work is to develop new methods that allow to perform searches according to the "attribute-value" model about these documents, where the "attributes" are, for example, column or row headers in tables and the "values" are the corresponding table cells. For this purpose, we will rely on the so-called probabilistic indexing framework (which in a certain sense is related with the field known as "keyword spotting"). In this framework, each element of an image that can be interpreted as a word is detected and stored, along with its position within the image and the correspondence relevance probability. This way, by using the geometric information available in the probabilistic indices and Gaussian distributions, we aim at allowing this type of search from a completely probabilistic perspective. Following this approach, in addition to information search, we study how to actually extract specific textual contents of the digital images in standard formats compatible with conventional databases.Andrés Moreno, J. (2021). Search and information extraction in handwritten tables. Universitat Politècnica de València. http://hdl.handle.net/10251/172740TFG

Space programs summary no. 37-56, volume 1 for the period 1 January to 28 February 1969. Flight projects

Mariner Mars 1969 Project, Mariner Mars 1971 Project, and Viking Project description

Reverse engineering and rapid prototyping in intervertebral disc tissue engineering

Intervertebral disc (IVD) degeneration disease (IDD) is considered the main cause for low back pain (LBP), which has a world socioeconomic burden of 70 billion euros a year. Tissue Engineering (TE) is an exponentially growing area due to its potential of finding patient-specific treatments in terms of immunological compatibility by using the patient’s own cells. Though, it is possible to increase TE patient-specificity by combining other technologies such as Reverse Engineering (RE) and Rapid Prototyping (RP). In this sense, it is possible to prepare a biodegradable scaffold that is both immunological and structurally compatible. This strategy has the potential to significantly increase implant integration and decrease immunological rejection, allowing the scaffold to be progressively replaced with newly synthesised tissue to ultimately regenerate the IVD into a fully functional anatomical motion segment. Herein is reported a preliminary proof-of-concept for that strategy using rabbit IVD’s cells as well as morphology and structure. In this sense, the annulus fibrosus (AF) structure was replicated by RE and RP into a polycaprolactone scaffold, and the cells were encapsulated in methacrylated gellan gum (GG-MA) hydrogel as a nucleus pulposus (NP) substitute. The AF scaffold’s cytotoxicity, mechanical behaviour, porosity and superficial morphology were also analysed. It was observed a significant level of biocompatibility from the AF replica and a similar porosity in relation with the native IVD. Cell adhesion, proliferation and viability were assessed until 21 days of culture in GG-MA. The metabolic activity was higher in the NP cells than in the fibroblast cell line, both cultured in GG-MA. In the future, this novel strategy is envisaged to treat IDD, and remove LBP, by fully regenerating the intervertebral disc.A degeneração do disco intervertebral é considerada a maior causa de dor lombar, que por sua vez tem um impacto socioeconómico mundial na ordem dos 70 mil milhões de euros por ano. A Engenharia de Tecidos é uma área de investigação que está a crescer exponencialmente e que tem o potencial de desenvolver novos tratamentos, livres de rejeição imunológica, uma vez que são utilizadas células do próprio paciente. No entanto, é possível aumentar esse potencial de compatibilidade com o paciente combinando Engenharia Reversa com Prototipagem Rápida. Com isto visa-se o desenvolvimento de uma estrutura biodegradável e compatível tanto imunologicamente com estruturalmente, que vai sendo progressivamente substituída por novo tecido até se alcançar uma regeneração definitiva do disco intervertebral. A prova-de-conceito preliminar desta estratégia terapêutica é reportada neste estudo através da utilização tanto de células, como a própria estrutura e morfologia, do disco intervertebral de coelho. A estrutura do anel fibroso foi replicada por Engenharia Reversa e Prototipagem Rápida em policaprolactona, enquanto que para servir como substituto do núcleo pulposo foram encapsuladas células num hidrogel de goma gelana metacrilada. A citotoxicidade, comportamento mecânico, morfologia superficial e porosidade da réplica do anel fibroso foram analisadas. Verificou-se que a porosidade é similar ao disco nativo e que o nível de biocompatibilidade está acima de 80%. As imagens de miscroscopia mostraram que as várias camadas da estrutura apresentam uma boa ligação após a solidificação do polímero. A adesão, proliferação e viabilidade celular na goma gelana metacrilada foram analisadas até 21 dias de cultura. Observou-se uma maior actividade metabólica nas células do núcleo pulposo do que na linha celular de fibroblastos, ambas encapsuladas em goma gelana metacrilada. Como trabalho futuro, pretende-se utilizar esta estratégia para tratar casos de degeneração do disco de uma forma efetiva em que o resultado final, após absorção da estrutura, é um disco intervertebral nativo biomecanicamente funcional

Vat 3D printable materials and post-3D printing procedures for the development of engineered devices for the biomedical field

L'abstract è presente nell'allegato / the abstract is in the attachmen

Image Segmentation and Classification using Small Data: An Application on Friendly Statements - A Computer Vision and Document Intelligence Project

Internship Report presented as the partial requirement for obtaining a Master's degree in Data Science and Advanced Analytics, specialization in Data ScienceInsurance companies face significant challenges in managing numerous physical documents containing critical information, resulting in considerable time and cost expenditures. Although Deep Learning models offer a promising solution, their implementation costs and data privacy concerns restrict widespread adoption, especially when dealing with confidential documents. This internship report presents a novel approach to address these challenges by developing a lightweight computer vision solution for accurately detecting and processing checkboxes from Portuguese friendly statements. The key objective was to demonstrate the feasibility of achieving high accuracy without relying on advanced Deep Learning techniques. By leveraging a small set of examples, we successfully extracted checkbox information while mitigating the high computational requirements associated with traditional Deep Learning models. The results highlight the practicality and cost-effectiveness of our approach, offering insurance companies a viable solution to streamline document management, enhance data security, and improve overall efficiency. This research contributes to the computer vision field by providing valuable insights into alternative methodologies that can be adopted to overcome the limitations of Deep Learning, facilitating broader accessibility and utilization among insurance providers

Optoelectronic sensors based on molecularly imprinted polymers

La ricerca è stata incentrata sullo sviluppo di sensori ottici (senza impiego di indicatori) basati su fibre ottiche plastiche (POF). Queste presentano caratteristiche vantaggiose come flessibilità, grande apertura numerica e facile lavorazione; essendo inoltre in grado di sopportare curvature più strette rispetto alle fibre di vetro. Pertanto, le POF risultano adatte alla realizzazione di sensori ottici ad alta sensibilità, miniaturizzati, robusti ed a basso costo. Due approcci differenti sono stati impiegati: il primo è stato basato sullo sviluppo dei sensori direttamente sulle fibre ottiche plastiche (POF) (sensori intrinseci) e il secondo prevede l'impiego di diverse guide d'onda ad esempio in PMMA o PET (sensori estrinseci). I due approcci mostrano caratteristiche distinte per la facile preparazione e sono stati studiati al fine di ottenere una migliore riproducibilità. I sensori sfruttano diversi fenomeni ottici: la risonanza plasmonica di superficie (SPR) o l'accoppiamento di onde evanescenti (EWC). Tutti i sensori impiegano recettori biomimetici sintetici, cioè polimeri a stampo molecolare (MIP) per il rilevamento di analiti in matrici complesse acquose o organiche. I bio-recettori comunemente usati, nonostante la loro elevata selettività e sensibilità, soffrono di grossi svantaggi quali la non disponibilità per tutti i substrati, il limite di analisi in condizioni biologiche e la costosa e lunga procedura per il loro utilizzo. Invece i MIP risultano più resistenti, anche in condizioni di analisi più drastiche (elevate T, bassi pH,…), pur mantenendo affinità e selettività elevate, pari a quelle dei bio-recettori. Tali caratteristiche rendendo questi recettori sintetici utili ai fini sensoristici. Sono stati sviluppati MIP specifici, basati su monomeri funzionali che impiegano interazioni non covalenti con comune composizione riguardo il monomero funzionale e il cross-linker. In alcuni casi, la composizione MIP è stata ottimizzata mediante metodi computazionali considerando diversi monomeri funzionali e cross-linker nonché possibili interazioni interferenti. Le caratteristiche dei MIP, come costante di affinità, capacità di assorbimento e selettività sono state valutate mediante procedura di equilibrazione batch e procedura a flusso. Differenti formulazioni di MIP in forma di particelle porose e sferiche sono state considerate. Sono stati sviluppati e caratterizzati MIP per l'analisi delle seguenti molecole: furaldeide (2-FAL) e dibenzildisolfuro (DBDS) data la loro importanza come utili indicatori dell'usura dei trasformatori di media tensione. La 2-FAL è stata considerata anche in matrici acquose, data la sua rilevanza nel controllo qualità degli alimenti. I sensori ottici sono stati caratterizzati determinando le isoterme di adsorbimento sullo strato polimerico, basato sulla risposta del sensore. I sensori SPR risultano promettenti grazie alla elevata sensibilità, al basso costo e alla possibilità di miniaturizzazione impiegando le POF. Inoltre, l'impiego di MIP come recettore garantiscono un'elevata selettività e costante di affinità (Kaff), un basso LOD e la possibilità del riutilizzo. Simili risultati sono stati ottenuti con sensori basati sull'accoppiamento di onde evanescenti (EWC) che tuttavia risultano più promettenti delle piattaforme SPR presentando il vantaggio dell'eliminazione dello strato di oro e quindi una migliore riproducibilità. Inoltre, nuovi materiali per l'imprinting molecolare sono stati considerati per migliorare la biocompatibilità. In particolare, la fibroina della seta è stata esaminata date le sue ottimali proprietà ottiche e meccaniche ed essendo un biomateriale già approvato per applicazioni biomediche. Risultati preliminari sull'imprinting di fibroina con glucosio sono stati promettenti; riscontrando un fattore di imprinting superiore a uno. Tale materiale stampato è facilmente ottenuto come strato sottile adatto allo sviluppo di sensori.The research was focused on the development of marker-free optical sensors based on plastic optical fibers (POF). These are particularly suitable for sensing application because of their exceptional flexibility, large numerical aperture, and easy manipulation. Also, they are able to withstand smaller bend radii than glass fibers. Therefore, POFs are suitable for the realization of low-cost and miniaturized optical sensors both robust and highly sensitive for application with a remote control. Two approaches have been exploited the first in which the optical platform was directly developed on plastic optical fibers (POF) (intrinsic sensors) and the second that employ different waveguides made for example of PMMA or PET (extrinsic sensors). The two approaches show distinct characteristics of easy preparation and have been investigated to obtain a better reproducibility. In both sensors, different optical phenomena have been exploited, in particular, surface plasmon resonance (SPR) and the evanescent wave coupling (EWC). All the sensors employ synthetic biomimetic receptors, i.e. molecularly imprinted polymers (MIPs) for the detection of analytes in complex aqueous or organic matrices. The most commonly used bio-receptors, despite their high selectivity and sensitivity, suffer from great disadvantages as not being available for all the substrate, being limited to the biological condition of analysis and requiring an expensive and time-consuming development procedure. Instead, MIPs are more resistant, even in harsh conditions of analysis, while maintaining the high affinity and selectivity of the biological receptors, so making these synthetic receptors really promising for sensing purposes. Some specific MIPs have been developed, based on non-covalent interactions template-functional monomers, and with the most common composition as far as the functional monomer and the cross-linker are concerned. In some cases, the MIP composition was optimized by computational methods considering different functional monomers and cross-linkers as well as possible interfering interactions. The MIPs characteristics, as the affinity constant, the capacity of uptake and selectivity have been evaluated by batch procedure and the flow procedure. Porous MIP particles and MIP beads have been considered and characterized by batch equilibration. In particular MIPs for sensing the following molecules have been developed and characterized: 2-FAL (2-furhaldehide) and dibenzyldisulfide (DBDS) because of their rising importance as useful markers of health status of the middle tension transformers in the large distribution energy. 2-FAL was considered in aqueous matrices too, in view of its relevance in food quality control. The optical sensors developed have been characterized by determining the adsorption isotherms on the polymeric layer, based on the sensor response. The sensors based on SPR appear to be really promising due to the optimal sensitivity, low cost and possibility of miniaturization by employing POFs. Moreover, a high selectivity and affinity constant (Kaff), a low LOD and the possibility of the re-use are provided by the successful implementation of MIPs as receptors. Similar optimal results have been obtained by the evanescent wave coupling (EWC) moreover this platform presents the advantages of avoiding the use of Au layer, so could be superior to the SPR ones for the better reproducibility. Also, new kinds of molecularly imprinted materials have been considered in order to improve the biocompatibility of the sensing devices. In particular silk fibroin has been examined for its good optical and mechanical characteristics. Moreover, it is a biomaterial already approved for biomedical applications. Preliminary results on the imprinting of fibroin with glucose have been promising, with an imprinting factor higher than one. Moreover, the imprinted material can easily obtain a thin layer, which is particularly suitable for sensor development

The electric and magnetic form factors of the proton

The paper describes a precise measurement of electron scattering off the proton at momentum transfers of $0.003 \lesssim Q^2 \lesssim 1$\ GeV$^2$. The average point-to-point error of the cross sections in this experiment is $\sim$ 0.37%. These data are used for a coherent new analysis together with all world data of unpolarized and polarized electron scattering from the very smallest to the highest momentum transfers so far measured. The extracted electric and magnetic form factors provide new insight into their exact shape, deviating from the classical dipole form, and of structure on top of this gross shape. The data reaching very low $Q^2$ values are used for a new determination of the electric and magnetic radii. An empirical determination of the Two-Photon-Exchange (TPE) correction is presented. The implications of this correction on the radii and the question of a directly visible signal of the pion cloud are addressed.Comment: 38 pages, 20 figures. Updated data files. PRC versio

Optoelectronic sensors based on molecularly imprinted polymers

La ricerca è stata incentrata sullo sviluppo di sensori ottici (senza impiego di indicatori) basati su fibre ottiche plastiche (POF). Queste presentano caratteristiche vantaggiose come flessibilità, grande apertura numerica e facile lavorazione; essendo inoltre in grado di sopportare curvature più strette rispetto alle fibre di vetro. Pertanto, le POF risultano adatte alla realizzazione di sensori ottici ad alta sensibilità, miniaturizzati, robusti ed a basso costo. Due approcci differenti sono stati impiegati: il primo è stato basato sullo sviluppo dei sensori direttamente sulle fibre ottiche plastiche (POF) (sensori intrinseci) e il secondo prevede l'impiego di diverse guide d'onda ad esempio in PMMA o PET (sensori estrinseci). I due approcci mostrano caratteristiche distinte per la facile preparazione e sono stati studiati al fine di ottenere una migliore riproducibilità. I sensori sfruttano diversi fenomeni ottici: la risonanza plasmonica di superficie (SPR) o l'accoppiamento di onde evanescenti (EWC). Tutti i sensori impiegano recettori biomimetici sintetici, cioè polimeri a stampo molecolare (MIP) per il rilevamento di analiti in matrici complesse acquose o organiche. I bio-recettori comunemente usati, nonostante la loro elevata selettività e sensibilità, soffrono di grossi svantaggi quali la non disponibilità per tutti i substrati, il limite di analisi in condizioni biologiche e la costosa e lunga procedura per il loro utilizzo. Invece i MIP risultano più resistenti, anche in condizioni di analisi più drastiche (elevate T, bassi pH,…), pur mantenendo affinità e selettività elevate, pari a quelle dei bio-recettori. Tali caratteristiche rendendo questi recettori sintetici utili ai fini sensoristici. Sono stati sviluppati MIP specifici, basati su monomeri funzionali che impiegano interazioni non covalenti con comune composizione riguardo il monomero funzionale e il cross-linker. In alcuni casi, la composizione MIP è stata ottimizzata mediante metodi computazionali considerando diversi monomeri funzionali e cross-linker nonché possibili interazioni interferenti. Le caratteristiche dei MIP, come costante di affinità, capacità di assorbimento e selettività sono state valutate mediante procedura di equilibrazione batch e procedura a flusso. Differenti formulazioni di MIP in forma di particelle porose e sferiche sono state considerate. Sono stati sviluppati e caratterizzati MIP per l'analisi delle seguenti molecole: furaldeide (2-FAL) e dibenzildisolfuro (DBDS) data la loro importanza come utili indicatori dell'usura dei trasformatori di media tensione. La 2-FAL è stata considerata anche in matrici acquose, data la sua rilevanza nel controllo qualità degli alimenti. I sensori ottici sono stati caratterizzati determinando le isoterme di adsorbimento sullo strato polimerico, basato sulla risposta del sensore. I sensori SPR risultano promettenti grazie alla elevata sensibilità, al basso costo e alla possibilità di miniaturizzazione impiegando le POF. Inoltre, l'impiego di MIP come recettore garantiscono un'elevata selettività e costante di affinità (Kaff), un basso LOD e la possibilità del riutilizzo. Simili risultati sono stati ottenuti con sensori basati sull'accoppiamento di onde evanescenti (EWC) che tuttavia risultano più promettenti delle piattaforme SPR presentando il vantaggio dell'eliminazione dello strato di oro e quindi una migliore riproducibilità. Inoltre, nuovi materiali per l'imprinting molecolare sono stati considerati per migliorare la biocompatibilità. In particolare, la fibroina della seta è stata esaminata date le sue ottimali proprietà ottiche e meccaniche ed essendo un biomateriale già approvato per applicazioni biomediche. Risultati preliminari sull'imprinting di fibroina con glucosio sono stati promettenti; riscontrando un fattore di imprinting superiore a uno. Tale materiale stampato è facilmente ottenuto come strato sottile adatto allo sviluppo di sensori.The research was focused on the development of marker-free optical sensors based on plastic optical fibers (POF). These are particularly suitable for sensing application because of their exceptional flexibility, large numerical aperture, and easy manipulation. Also, they are able to withstand smaller bend radii than glass fibers. Therefore, POFs are suitable for the realization of low-cost and miniaturized optical sensors both robust and highly sensitive for application with a remote control. Two approaches have been exploited the first in which the optical platform was directly developed on plastic optical fibers (POF) (intrinsic sensors) and the second that employ different waveguides made for example of PMMA or PET (extrinsic sensors). The two approaches show distinct characteristics of easy preparation and have been investigated to obtain a better reproducibility. In both sensors, different optical phenomena have been exploited, in particular, surface plasmon resonance (SPR) and the evanescent wave coupling (EWC). All the sensors employ synthetic biomimetic receptors, i.e. molecularly imprinted polymers (MIPs) for the detection of analytes in complex aqueous or organic matrices. The most commonly used bio-receptors, despite their high selectivity and sensitivity, suffer from great disadvantages as not being available for all the substrate, being limited to the biological condition of analysis and requiring an expensive and time-consuming development procedure. Instead, MIPs are more resistant, even in harsh conditions of analysis, while maintaining the high affinity and selectivity of the biological receptors, so making these synthetic receptors really promising for sensing purposes. Some specific MIPs have been developed, based on non-covalent interactions template-functional monomers, and with the most common composition as far as the functional monomer and the cross-linker are concerned. In some cases, the MIP composition was optimized by computational methods considering different functional monomers and cross-linkers as well as possible interfering interactions. The MIPs characteristics, as the affinity constant, the capacity of uptake and selectivity have been evaluated by batch procedure and the flow procedure. Porous MIP particles and MIP beads have been considered and characterized by batch equilibration. In particular MIPs for sensing the following molecules have been developed and characterized: 2-FAL (2-furhaldehide) and dibenzyldisulfide (DBDS) because of their rising importance as useful markers of health status of the middle tension transformers in the large distribution energy. 2-FAL was considered in aqueous matrices too, in view of its relevance in food quality control. The optical sensors developed have been characterized by determining the adsorption isotherms on the polymeric layer, based on the sensor response. The sensors based on SPR appear to be really promising due to the optimal sensitivity, low cost and possibility of miniaturization by employing POFs. Moreover, a high selectivity and affinity constant (Kaff), a low LOD and the possibility of the re-use are provided by the successful implementation of MIPs as receptors. Similar optimal results have been obtained by the evanescent wave coupling (EWC) moreover this platform presents the advantages of avoiding the use of Au layer, so could be superior to the SPR ones for the better reproducibility. Also, new kinds of molecularly imprinted materials have been considered in order to improve the biocompatibility of the sensing devices. In particular silk fibroin has been examined for its good optical and mechanical characteristics. Moreover, it is a biomaterial already approved for biomedical applications. Preliminary results on the imprinting of fibroin with glucose have been promising, with an imprinting factor higher than one. Moreover, the imprinted material can easily obtain a thin layer, which is particularly suitable for sensor development