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Mean-based reconstruction is a fundamental, natural approach to worst-case trace reconstruction over channels with synchronization errors. It is known that $\exp(O(n^{1/3}))$ traces are necessary and sufficient for mean-based worst-case trace reconstruction over the deletion channel, and this result was also extended to certain channels combining deletions and geometric insertions of uniformly random bits. In this work, we use a simple extension of the original complex-analytic approach to show that these results are examples of a much more general phenomenon: $\exp(O(n^{1/3}))$ traces suffice for mean-based worst-case trace reconstruction over any memoryless channel that maps each input bit to an arbitrarily distributed sequence of replications and insertions of random bits, provided the length of this sequence follows a sub-exponential distribution.

This paper describes the fabrication of silicon neural probes based on low-cost semiconductor technologies, such as photolithography, thin-films deposition and blade dicing. Each 8 mm long fabricated neural probe has 13 platinum recording sites (microelectrodes) with different dimensions, ranging from 50 × 50 μm2 to 300 × 300 μm2. The platinum microelectrodes impedance were characterized through electrochemical impedance spectroscopy with results ranging from 5 kΩ to 600 kΩ at 1 kHz. Local field potentials were recorded when performing in-vivo electrophysiological recordings on an adult mouse. The results demonstrate the functionality of the neural probe, by acquiring local field potentials activity even with a microelectrode area of 50 × 50 μm2. Moreover, the results suggest a robust and versatile fabrication process avoiding etching processes.

This paper presents a capacitive modulator design and modeling using poly-si and silicon technologies. We propose a methodology involving the entire modulator design process, from the optical design, charge distribution calculation and small-signal RF analysis. Thus, in the case of silicon photonics modulators, the paper proposes means to optimize the trade-offs among several figures of merit. It is shown that high bandwidth operation (>30 GHz) can be achieved by sacrificing a little the modulation efficiency. info:eu-repo/semantics/publishedVersion

We present new capacity upper bounds for the discrete-time Poisson channel with no dark current and an average-power constraint. These bounds are a simple consequence of techniques developed by one of the authors for the seemingly unrelated problem of upper bounding the capacity of binary deletion and repetition channels. Previously, the best known capacity upper bound in the regime where the average-power constraint does not approach zero was due to Martinez (JOSA B, 2007), which we re-derive as a special case of our framework. Furthermore, we instantiate our framework to obtain a closed-form bound that noticeably improves the result of Martinez everywhere.

Medical devices have a great impact but rigorous production and quality norms to meet, which pushes manufacturing technology to its limits in several fields, such as electronics, optics, communications, among others. This paper briefly explores how the medical industry is absorbing many of the technological developments from other industries, and making an effort to translate them into the healthcare requirements. An example is discussed in depth: implantable neural microsystems used for brain circuits mapping and modulation. Conventionally, light sources and electrical recording points are placed on silicon neural probes for optogenetic applications. The active sites of the probe must provide enough light power to modulate connectivity between neural networks, and simultaneously ensure reliable recordings of action potentials and local field activity. These devices aim at being a flexible and scalable technology capable of acquiring knowledge about neural mechanisms. Moreover, this paper presents a fabrication method for 2-D LED-based microsystems with high aspect-ratio shafts, capable of reaching up to 20 mm deep neural structures. In addition, PDMS glenses on LEDs top surface are presented for focusing and increasing light intensity on target structures., This work was supported in part by FCT with the reference Project UID/EEA/04436/2013, in part by the FEDER funds through the COMPETE 2020-Programa Operacional Competitividade e Internacionalizaca o (POCI) with the reference Project POCI-01-0145-FEDER-006941, and in part by the ANI through the Brain-Lighting Project by FEDER funds through Portugal 2020, COMPETE 2020 with the reference POCI-01-0247-FEDER-003416. The work of S. B. Goncalves was supported by the Portuguese Foundation for Science and Technology (FCT) under Grant PD/BD/105931/2014, MIT Portugal Program, and in pail by the Luso-American Development Foundation. The associate editor coordinating the review of this paper and approving it for publication was Prof. Octavian Postolache. (Corresponding author: S. B. Goncalves.)

This paper describes the design and development of an autonomous robot for the Robot@Factory league at “Festival Nacional de Robótica 2016”, held in Bragança, Portugal. This paper describes all the hardware and software components developed for a localization and performance of the robot according to the rules. The challenge consists of a table setup that recreates an industrial environment where a robot has to successfully transport boxes from an initial warehouse to the final warehouse. The destination to which the robot has to carry each box, depends on the state of the box, i.e., depending on the box LED color, even though in some cases the robot has to leave the box temporarily in the called processing machines (which are intermediate stations). The most significant innovation feature of this robot prototype consists of the possibility of carrying up to three boxes simultaneously while being able to select which box to drop. This project was developed with great success, since the team managed to reach the 3rd place in the competition., (undefined), info:eu-repo/semantics/publishedVersion

Minimally invasive medical devices are widely investigated, because of their advantages for in-situ medical examination in real time with highly reduced risk and patient discomfort, as compared to more traditional approaches. Optical biopsy is a prominent example of this trend and provides essential diagnostic information on tissue histopathology in the gastrointestinal tract. Micro-electro mechanical system (MEMS) technology is demonstrated in this paper to be highly suitable for fabrication of an optical biopsy microsystem where overall system dimensions and power consumption are key enabling factors. The biopsy microsystem presented is 11.2 mm in diameter and 18.6 mm in length and contains an imaging system with a dedicated image magnification optical microsystem (IMOM) and light emitting diodes (LEDs). Polydimethylsiloxane (PDMS) microlenses have been fabricated using the ‘hanging droplet’ approach and integrated in the IMOM subsystem for achieving an image magnification by a factor 4 and a 30% improvement in optical irradiance from the LED illumination., This work was supported by the Portuguese Foundation for Science and Technology (FCT) with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 - Programa Operacional Competitividade e Internacionalizacão (POCI) with the reference project POCI- 01-0145-FEDER-006941. S. B. Goncalves is fully supported by the FCT under grant PD/BD/105931/2014., info:eu-repo/semantics/publishedVersion

In this paper we provide a generalization of weak oblivious transfer through the constructive cryptography framework. This generalization requires the global order of the inputs and outputs from and to two parties called Alice and Bob to be completely defined, a subtlety which has been overlooked by previous work on the subject. We provide evidence that the order of inputs and outputs in weak oblivious transfer matters. In particular, it may influence the kind and strength of symmetry results which can be obtained about such resources.

Flexible thin-film rechargeable lithium battery was fabricated only by PVD techniques. The Kapton® substrate provides flexibility to the battery and at the same time supports the depositions conditions inside the vacuum chamber. Platinum and titanium were deposited by e-beam and used as cathode and anode current collectors of the battery, respectively. LiCoO2 cathode was deposited by rf-sputtering with 150 W of power source, 40 sccm of Ar and 300°C in the substrate during deposition. The electrolyte LiPON was also deposited by rf-sputtering and the conditions explained before in J. F. Ribeiro, et al., [1]. The anode, lithium, was deposited with 3 μm thickness by thermal evaporation. The open circuit potential, Nyquist diagrams and charge/discharge capacity were used for battery characterization. The modelling of Nyquist equivalent circuit allowed calculating some battery parameters, like, internal resistance, battery charge resistance and battery effective diffusion coefficient. The equivalent circuit and the parameters were calculated with the help of Zview™ software.

Batteries are crucial for most of bio applications. Batteries based on a liquid or polymer electrolyte needs a weight protective packaging which decreases their energy density and increases their size. This paper aims to identify, on the one hand, the efforts performed in thin-film batteries until now, and on the other hand, to provide an overview about the future perspectives in integration of batteries with flexible electronic circuits and energy harvesting systems. The overview highlights the need for an on-going investigation that aims to replace metallic lithium anode of batteries through different approaches. Other materials, namely silicon or germanium, seem promising when combined with nanostructures. Three dimensional and integrated batteries will increase its volumetric capacity.

This paper presents a low-cost technology for fabricating optical filters arrays tuned for the primary colors. The fabrication process presented in this paper is intended for directly printing the optical filters into a transparent flexible substrate (acetate). The target application of these optical filters is for enabling the acquisition of multicolor stereoscopic images with a sensor made in CMOS technology.

Microelectrodes are widely used to record biological signals from living tissue, namely in neuroscience where researches need to record brain signals in vivo. Several types of microelectrodes are available in the market. Unfortunately, most of the microelectrode developing processes are time consuming and expensive. This work presents a rapid low-cost prototyping technology for protocol-specific microelectrode designs. The suggested fabrication process combines SU-8 photoresist patterning in multiple layers with the deposition of intermediate conductive layers (Au layer in the presented case). The fabricated microelectrodes were specifically designed for an electrophysiological experiment that required simultaneous recording in the pre-frontal cortex (PFC) and stimulation in the hippocampus of the rat brain. After electrode implantation surgery in an anesthetized rat, local-field potentials (LFP) from the PFC were acquired. The power spectra of the LFPs using the SU-8-based microelectrode and using a commercially available Pt-Ir electrode are comparable in a great extent. Staining of perfusion fixed brain slices showed that the electrodes targeted the correct brain regions. SU-8-based microelectrodes appear to be valuable as a rapid prototyping technology to design low-cost protocol-specific microelectrodes.

This paper presents a implantable wireless microsystem concept for operation in the 433 MHz ISM band. The proposed microsystem is composed by two independent subsystems: the electrostimulation and the radio-frequency (RF) subsystems. The electrostimulation part is a silicon box with groves to pass the nerves to be stimulated. The cover of the silicon box contains electrodes for electrical contacting with the nerves. Wafer-level packaging (WLP) techniques will allow the joining of the RF and the electrostimulation subsystems. The target of this implantable microsystem is for RF reception at 433 MHz of user commands to activate the micturition function and the erection (on males) patients. The expected microsystem area will be of 5×5mm2.

This paper presents a new wireless microsystem for for use in urology. This microsystem is composed by two parts: the electrostimulation and the radio-frequency (RF) subsystems. The electrostimulation part is a silicon box with groves to pass the nerves to be stimulated. Above the stimulation box is putted a cover containing electrodes to do the electrical contacts with the nerves. Using wafer-level packaging (WLP) techniques the RF and the electrostimulation parts are joined together. This implantable microsystem allows the reception of RF signals with user commands to activate the micturition function and the penian erection (on males) patients. The microsystem has an expected area of 5×5 mm2.