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Inkjet printing is an established technology that has been revisited in recent years for the low-cost and easy production of electrical sensing and biosensing systems. With this technique, it is possible to produce flexible microsystems on eco-compatible substrates such as polymers and paper. In this sense, we investigated the printing performances of a common office inkjet printer and of a commercial conducting ink, to produce aptamer-based electrochemical biosensors for antibiotics detection. During our analysis we characterized both the morphological and electrical properties of the printed electrodes, considering also their stability over time and tuning all the parameters to obtain reproducible micrometric systems. The produced devices proved to be able to undergo aptamer functionalization and to detect Ampicillin, a common used antibiotic, in few minutes with a LOD of 10 μg/ml in milk. Therefore, in this preliminary work we demonstrated the feasibility of low-cost customized inkjet-printed biosensors, and their possible use to prevent both antibiotic contaminations and antibiotic resistance development.

COVID-19 is a highly diffuse respiratory infection caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Currently, quantitative real-time polymerase chain reaction (qRT-PCR) technology is commonly used in clinical diagnosis of COVID-19. However, this method is time-consuming and labor-intensive, which is limited in clinical application. Here, we propose a new method for the ultrasensitive and visual detection of SARS-CoV-2 viral nucleic acid. The assay integrates with a paper device and highly efficient isothermal amplification technology - Netlike rolling circle amplification (NRCA), which can reach a limit of detection of 4.12 aM. The paper-based NRCA owns advantages of specificity, portability, visualization and low-cost. Therefore, this method can effectively meet the requirements of point-of-care testing, providing a novel molecular detection technology for clinical diagnosis of COVID-19 and promoting the development of NRCA devices., Graphical Abstract ga1

[EN] A new concept for fluid flow manipulation in microfluidic paper-based analytical devices (m-PADs) is presented by introducing ionogel materials as passive pumps. m-PADs were fabricated using a new doubleside contact stamping process and ionogels were precisely photopolymerised at the inlet of the m-PADs.The ionogels remain mainly on the surface of the paper and get absorbed in the superficial paper-fibers allowing for the liquid to flow from the ionogel into the paper easily. As a proof of concept the fluid flowand mixing behaviour of two different ionogels mPADs were compared with the non-treated mPADs.It was demonstrated that both ionogels highly affect the fluid flow by delaying the flow due to their different physical and chemical properties and water holding capacities. The project was carried out with the support of the Ramón y Cajal programme (Ministerio de Economía y Competitividad). FBL and JS thank to the European Union's Seventh Framework Programme (FP7) for Research, Technological Development and Demonstration under grant agreement no. 604241 for economical support. JE acknowledges the Gobierno Vasco, Dpto. Industria,Innovación, Comercio y Turismo under ETORTEK IE14-391 andELKARTEK KK-2015/00088. Authors personally acknowledge Marian M. De Pancorbo for letting them use her laboratory facilities at UPV/EHU.

The use of natural esters as an insulating liquid has become popular since the early 2000s. Studies in the literature emphasize the superiority of natural esters as compared to mineral oils. In these studies, the prominent properties of natural esters are presented as being environmentally friendly, safe, and delaying the aging of cellulosic insulation material. Although there is no doubt in terms of their characteristics, such as being environmentally and safe, exaggerated comments are made about the delay of aging of the paper material used in the insulation of transformer windings. This is because comparative experimental applications on mineral oil and natural esters are carried out under artificial and equal conditions provided in the laboratory environment. Whereas, performing these experiments on identical transformers will give more realistic results. In this study, two identical transformers were designed and equipped with precision fiber optic temperature sensors. Temperature differences that vary depending on the load between high voltage and low voltage windings were measured with a high degree of accuracy for both identical transformers. Besides these measurements, physical and chemical changes were analyzed on samples taken from insulation liquids. It was observed that the physical and chemical properties of the insulation liquids directly affect the operating performance of the transformers. Thanks to the differences in viscosity of insulating liquids, the heat dissipation due to losses in the windings were different for both transformers. Both heat distribution and temperature differences in the windings varied depending on the loading factors. Considering all these factors together, comprehensively evaluations were made on the aging rate of cellulosic insulation and the service life of the transformers. [Teydeb-3100329] We would like to thank Schneider Electric for allowing working together at the prototype product testing and evaluating processes. These processes were funded by the industry R&D projects support program (Teydeb-3100329). WOS:000594691900014 2-s2.0-85091340419

The bodily aspects of reading/writing practices are investigated in Finland.The paper is considered more adaptive to varied reading purposes than the screen.Handwriting is described as a more flexible and relaxed practice than typing.Skills determine less than materials and images the practices of reading/writing.Digital interfaces determine the ways we read and write less than suggested. This article investigates the different shapes in which reading and writing practices occur when paper/pen are compared with keyboard/screen. The focus is on the bodily aspects of these practices. Reading and writing are viewed as techniques of the body, which over the years have become increasingly mediated by technologies. The analysis is grounded in the theory of social practice. Research material consists of written essays collected from 25 students at the University of Jyvaskyla, Finland, in 2013. Results show that paper as material is considered suitable and adaptive to numerous reading purposes and bodily positions, while regarding the screen the places and positions of reading are viewed as more limited due to the material boundary conditions presented by devices. Students describe handwriting as a more flexible and relaxed bodily practice than typing, although the worsening skills of handwriting are recognized too. Skills and competences turned out to be less decisive factors than materials and images when trying to explain the differences in reading and writing practices when a paper/pen is compared with a keyboard/screen. Finally, the study argues that digital reading writing interfaces do not determine the ways we read and write as strongly as previously suggested.

The rapid development of wearable sensing technology exhibits unprecedented opportunities for artificial intelligence by establishing an interactive interface between the physical and the virtual worlds. Energy preservation and multi-functional integration are central for the enhancement of perception and sustainability of wearable electronics. Herein, to address the above two critical challenges, we presented a printed silk-fibroin-based triboelectric nanogenerator (PS-TENG), which can efficiently scavenge the bio-mechanical energy and precisely detect components of environmental humidity and human body motions simultaneously. An industrial mass-fabrication technology, i.e. screen-printing process, was successfully optimized to manufacture graphite-based microscale surface patterns atop polymeric soft substrate to form interdigital electrodes, which was covered by a thin layer of silk fibroin to realize the PS-TENG. The proposed wearable PS-TENG exhibited a remarkable output performance, and the voltage, the current and the power density achieved up to 666 V, 174.6 μA, 412 μW/cm2, respectively. Furthermore, this ultra-thin foldable PS-TENG possesses incredible features for multi-functional wearable sensing. With the help of the unique selective absorption property of silk fibroin, it was firstly reported that the existing states of water molecules (i.e., liquid and gaseous) in the air were successfully distinguished. Moreover, as attractive potential applications, it was demonstrated to accurately discriminate the health situation of human body (i.e., respiratory monitoring and joints motion recognizing) based on the capacitive and the triboelectric principles respectively, which is a novel combination of passive sensing and active sensing mechanisms within a single wearable device.

Many common and inexpensive materials, such as, paper, fabric and thread are currently being explored as alternate substrates for low-cost and field-based sensing applications. While these substrates have primarily been utilized to develop low-cost diagnostic devices, it is important to study whether these materials are suitable for more general chemical sensing applications. Here, we report chemical syntheses (inorganic and organic) and sensing using threads as microchannels. We first characterized the liquid transport through thread channels and then measured typical sample losses due to adsorption and evaporation. Next, we demonstrated synthesis of ferric hydroxide in a Y-geometry thread reactor and detected the product by colorimetry. Our low-cost device gave a product yield of 84% compared to a test tube-based synthesis. We also synthesized (with similar to 72% yield) and detected colorless 2,4-dichloro-N-(2-morpholinoethyl) benzamide in an attempt to demonstrate an organic reaction in a thread device. Finally, we successfully detected bovine serum albumin and the glucose present in blood plasma as examples of detection of chemical substances relevant in diagnostics. Our results indicate that cotton and silk threads are indeed suitable materials for incorporation into field-deployable disposable chemical reaction and sensing systems. (C) 2013 Elsevier B.V. All rights reserved.

Complex refractive index of strongly depolarizing starch acetate is investigated as a function of bulk package density, which is compulsory parameter in analysis of light scattering from nanoscale starch acetate pigments and fillers. The measurements were made using a laser-goniometer and spectrophotometer to gain data for refractive index analysis according to the Brewster’s law and Fresnel equations. The real part of refractive index was verified by microscopic immersion method.