System of Implantable Electrodes for Neural Signal Acquisition and Stimulation for Wirelessly Connected Forearm Prosthesis.

There is great interest in the development of prosthetic limbs capable of complex activities that are wirelessly connected to the patient's neural system. Although some progress has been achieved in this area, one of the main problems encountered is the selective acquisition of nerve impulses and the closing of the automation loop through the selective stimulation of the sensitive branches of the patient. Large-scale research and development have achieved so-called "cuff electrodes"; however, they present a big disadvantage: they are not selective. In this article, we present the progress made in the development of an implantable system of plug neural microelectrodes that relate to the biological nerve tissue and can be used for the selective acquisition of neuronal signals and for the stimulation of specific nerve fascicles. The developed plug electrodes are also advantageous due to their small thickness, as they do not trigger nerve inflammation. In addition, the results of the conducted tests on a sous scrofa subject are presented.

Pig Sedation and Anesthesia for Medical Research.

In clinical veterinary practice, proper training and expertise in anesthesia administration and monitoring are essential. Pigs are suitable experimental animals for many surgical techniques because they are similar in size to humans and have a short reproductive cycle. This makes them ideal for research concerning organ transplantation, cardiovascular surgery, and other procedures that require a large animal model. Sedation and premedication should be administered at the lowest dose to be effective with predictable results and reduced adverse effects, to ensure the safety of both the animal and the team involved in the procedure, with a fast onset and optimizing the induction and maintenance of anesthesia. The goal of induction is to achieve a safe and effective level of anesthesia that ensures patient safety and facilitates research. Most of the time, inhalation anesthesia with endotracheal intubation is the ideal choice for maintenance of anesthesia. The difficulties related to endotracheal intubation of pigs can be overcome by knowing the anatomical peculiarities. Effective analgesia tailored to the specific procedure, the pig's condition, and individual responses to medications should complete the maintenance and recovery protocols, reducing perioperative complications.

Decision Levels and Resolution for Low-Power Winner-Take-All Circuit.

Sensors in many applications must select the largest element in a sequence of currents. This can be performed in an analog way by the Winner-Take-All (WTA) circuit. This paper considers the classic version of the WTA Lazzaro circuit, working with MOS devices in a subthreshold regime. Since the separation of the gainer by analytically computable "decision levels" has recently been introduced, this paper aims to numerically verify and discuss these levels and their dependence on circuit and device parameters. For VT, the threshold voltage of MOS devices, which is primarily responsible for differences between components (mismatch), its relationship with the output voltages is theoretically demonstrated and numerically checked.

Remote Sensing System for Motor Nerve Impulse.

In this article, we present our research achievements regarding the development of a remote sensing system for motor pulse acquisition, as a first step towards a complete neuroprosthetic arm. We present the fabrication process of an implantable electrode for nerve impulse acquisition, together with an innovative wirelessly controlled system. In our study, these were combined into an implantable device for attachment to peripheral nerves. Mechanical and biocompatibility tests were performed, as well as in vivo testing on pigs using the developed system. This testing and the experimental results are presented in a comprehensive manner, demonstrating that the system is capable of accomplishing the requirements of its designed application. Most significantly, neural electrical signals were acquired and transmitted out of the body during animal experiments, which were conducted according to ethical regulations in the field.

The Impact of COVID-19 Pandemic During Lockdown on the Veterinary Profession in Romania: A Questionnaire-Based Survey.

The lockdown period in Romania lasted for 60 days and had the purpose of limiting the spread of SARS-CoV-2 virus outbreak and manage its consequences through emergency measures on many important areas of activity. This study aimed to gather, assess, analyze and disseminate relevant social, economic, and medical aspects on the impact of COVID-19 pandemic during lockdown on the veterinary profession in Romania. A survey was created using an online questionnaire platform, and disseminated. The survey was completed by a total of 409 individuals. A high number of respondents (71.64%; n = 293) felt exposed to medium or high risk of infection with SARS-CoV-2 at their workplace and many (56.97%; n = 233) felt that their professional environment was more stressful than usual during lockdown. Almost all respondents (89.73%; n = 367) declared the implementation of several control measures recommended by FECAVA and FVE (e.g., social distancing, wearing protective equipment, hand washing), but few mentioned the opportunity of remote work or visiting restrictions. Overall, the results show that the impact of lockdown lies directly on four main categories of importance on veterinarian professional's life-human resource, activity management, relationship between veterinarian and authorities, and continuing education.

A Consistent Model for Lazzaro Winner-Take-All Circuit With Invariant Subthreshold Behavior.

This paper considers the basic Lazzaro winner-take-all analog computing circuit with N current inputs, N voltage outputs, and a bias current. Motivated by low-power applications, we find a mathematical accurate model of the network when all MOS devices remain inside the subthreshold region all along the transient. This involves analytical inequalities relating the range of admissible input currents to transistor parameters, to supply voltage, and to bias current. The restrictions are sufficiently weak to allow extra demands of functionality or performance. The technical novelty here is that by a slight cut of the maximal subthreshold domain and by choosing proper coordinates, we get a ordinary differential equation invariance problem on a rectangle of ℜN+1 space which is analytically tractable. A more precise localization of the asymptotically stable steady state inside the region of interest is also inferred. Although the work is mainly theoretical, an effort to infer simple, interpretable formulas useful for synthesis has been made. The results are numerically verified and their feasibility is discussed in detail. The subject matter is new and it is worth extending it to larger classes of circuits with regional behavior.

New accurate and flexible design procedure for a stable KWTA continuous time network.

The classical continuous time recurrent (Hopfield) network is considered and adapted to K -winner-take-all operation. The neurons are of sigmoidal type with a controllable gain G, an amplitude m and interconnected by the conductance p. The network is intended to process one by one a sequence of lists, each of them with N distinct elements, each of them squeezed to [0,I] admission interval, each of them having an imposed minimum separation between elements z(min). The network carries out: 1) a matching dynamic process between the order of list elements and the order of outputs, and 2) a binary type steady-state separation between K and K+1 outputs, the former surpassing a +ξ threshold and the later falling under the -ξ threshold. As a result, the machine will signal the ranks of the K largest elements of the list. To achieve 1), the initial condition of processing phase has to be placed in a computable θ -vicinity of zero-state. This requires a resetting procedure after each list. To achieve 2) the bias current M has to be within a certain interval computable from circuit parameters. In addition, the steady-state should be asymptotically stable. To these goals, we work with high gain and exploit the sigmoid properties and network symmetry. The various inequality type constraints between parameters are shown to be compatible and a neat synthesis procedure, simple and flexible, is given for the tanh sigmoid. It starts with the given parameters N, K, I, z(min), m and computes simple bounds of p, G, ξ, θ, and M. Numerical tests and comments reveal qualities and shortcomings of the method.