Repetitive transcranial magnetic stimulation during a spatial memory task leads to a decrease in brain metabolic activity.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neuromodulation technique that is able to generate causal-based interferences between brain networks and cognitive or behavioral responses. It has been used to improve cognition in several disease models. However, although its exploration in healthy animals is essential to attribute its pure effect in learning and memory processes, studies in this regard are scarce. We aimed to evaluate whether rTMS leads to memory facilitation in healthy rats, and to explore the brain-related oxidative metabolism. We stimulated healthy Wistar rats with a high-frequency (100 Hz) and low-intensity (0.33 T) protocol during three consecutive days and evaluated the effect on the performance of an allocentric spatial reference learning and memory task. Following the last day of learning, we assessed oxidative brain metabolism through quantitative cytochrome c oxidase (CCO) histochemistry. The results showed that rTMS did not improve spatial memory in healthy rats, but the behavioral outcome was accompanied by a CCO reduction in the prefrontal, retrosplenial, parietal, and rhinal cortices, as well as in the striatum, amygdala, septum, mammillary bodies, and the hippocampus, reflecting a lower metabolic activity. In conclusion, rTMS induces a highly efficient use of brain regions associated with spatial memory.

Estimation of Blockage Position, Geometry, and Solidity in Molten Salt Pipelines.

In solar thermal plants, the use of molten salt as a heat transfer fluid is an advantageous alternative, although it has some disadvantages such as the formation of salt plugs in the pipes due to possible stratification of the salt or its solidification. The aim of this study was to implement an electromagnetic acoustic transducer (EMAT) not only capable of identifying the position of the plug, but also of determining whether the plug blocks the entire conductive surface or, on the contrary, is partial, allowing the fluid to pass through a smaller section. The proposed transducer is intended to be minimally invasive, allowing it to be used in the same way as a temperature probe. To do so, it creates torsional waves in the pipe, which are then used for a combination of measurements: pulse-echo and attenuation of the acoustic waves. Two materials with different densities (silicone and cement) were used in the tests carried out, which made it possible to check that for a given size of blockage, it is possible to identify the type of material from which it is formed.

Equipment for Repetitive Transcranial Magnetic Stimulation.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neuromodulation technique used for the treatment of a great variety of neurological disorders. The technique involves applying a magnetic field in certain areas of the cerebral cortex in order to modify neuronal excitability outside the skull. However, the exact brain mechanisms underlying rTMS effects are not completely elucidated. For that purpose, and in order to generate a pulsed magnetic field, a half-bridge converter controlled by a microcontroller has been designed to apply rTMS in small animals. Moreover, the small size of the rodent head makes it necessary to design a magnetic transducer, with the aim of focusing the magnetic field on selected brain areas using a specific and a small magnetic head. Using such devices, our purpose was to compare the effects of five different rTMS dosages on rat brain metabolic activity. The experimental results showed that one day of stimulation leads to an enhancement of brain metabolic activity in cortical areas, meanwhile with three days of stimulation it is possible to also modify subcortical zones, results that were not found when extending the number of rTMS applications up to seven days. In consequence, the number of pulses delivered might be an important parameter in rTMS protocols, highlighting its importance in rTMS impact.

Current State of Transcranial Magnetic Stimulation and its use in Psychiatry.

INTRODUCTION: Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation technique that could be used as a therapeutic intervention in order to treat psychiatric disorders. AIM: Reviewing the effectiveness of TMS in the modulation of cognitive functions and also detailing its potential applications in psychiatric treatments. DEVELOPMENT: TMS has been traditionally used for the treatment of a great variety of neurological or psychiatric conditions by modulating the activity in brain areas and networks. Therapeutic benefit has been found in depressive disorders, anxiety, schizophrenia, addiction, and neurodevelopmental disorders as well as in brain damage and neurodegenerative disorders. Moreover, TMS is a technique which offers great tolerance and can be used as complement with other therapies. However, it is not easy to define an optimal treatment for every pathology: the parameters of stimulation are variable, and its effects at the cellular level of the nervous system are not well-known. CONCLUSION: While it is true that TMS provides many therapeutic benefits, it requires further investigation. It is necessary to detail the action mechanism of the stimulation and the long-term side effects, if any. This information would allow the design of specific treatment protocols for different psychiatric disorders.

Real-time Automatic Calculation of Euro Coins and Banknotes in a Cash Drawer.

A very interesting and useful complement to classical cash-registers is presented in this paper, coming up with a real-time auto-counting solution for the money inside a cash drawer. The system allows knowing not only the total amount of money but also how many coins and banknotes there are of each value. The embedded solution developed has been intended to become a low-cost solution, allowing better control over the money and helping both owners and workers in the establishments. By using this system, new utilities including automatic final balancing, instant error handling when making operations, and the lack of certain types of banknotes or coins inside the drawer or the excess of some in a certain compartment, could be implemented. Coins-counting solution is based on their weight, and small individual scales made by load cells have been integrated in each coin compartment. With respect to the banknotes, an innovative alternative based on the electrical properties of capacitors is presented. Additionally, considering the relevance of interoperability in today's systems, a Bluetooth module has been integrated into the system, allowing for data to be accessed remotely from any smartphone, tablet or computer within the range of the module. In this work, an Android application to both control and interact with the system has also been designed.

Magnetostrictive Sensor for Blockage Detection in Pipes Subjected to High Temperatures.

The use of solar thermal power plants is considered a cost-effective alternative to produce renewable energy. Unlike other energy installations, in this type of plants the transfer and storage of energy has been solved by using molten salts. These salts run between two tanks through the steam generation system that feeds the turbine. Although the use of salts as a heat transfer fluid is considered an adequate solution, they are not without problems. One of them is the formation of blockages in the pipes due to a partial solidification of the salt, which leads to the shutdown of the installation, with the consequent economic losses. Fast location of these blockages in a minimally intrusive way is the objective pursued in this work. The method to achieve this is based on the use of a new magnetostrictive sensor that simplifies previous designs.

High frequency repetitive transcranial magnetic stimulation improves neuronal activity without affecting astrocytes and microglia density.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive neuromodulation technique capable of producing changes in the electrical potential of neurons. Currently, the application of rTMS in clinical practice and as a neurophysiological tool is increasing. However, the exact cellular mechanisms underlying rTMS-based therapies are not completely clear. Additionally, glial cells have been studied less. Our aim was to investigate the effect of three days of high-frequency rTMS on neuronal metabolism and neuronal activation, in addition to its effect on glial cells. For this purpose, we performed histochemistry and immunohistochemistry procedures: the histochemistry of cytochrome oxidase (COx) to assess neuronal metabolic activity, and the immunohistochemistry of c-Fos (marker of neuronal activity), GFAP (marker of astrocytic reactivity), and Iba1 (selective marker of reactive microglia). Our results showed enhanced metabolic activity after rTMS in the retrosplenial and parietal cortex and CA1 and CA3 subfields of the hippocampus. Moreover, higher c-Fos activity was found in the agranular retrosplenial cortex. Finally, we did not find changes between groups in the induction of astrocyte and microglia reactivity in any of the immunostained regions. In conclusion, we can assume that three days of high-frequency rTMS applied in healthy rats does not alter astroglia reactivity or inflammatory responses, such as microglia proliferation. Because we have shown an upregulation of neuronal metabolic activity in many limbic brain structures, in addition to higher c-Fos levels in the nearest cortical area to the rTMS, our work provides novel insight into the effectiveness and safety of rTMS as a brain modulation therapy.

Development of a wireless sensor network for individual monitoring of panels in a photovoltaic plant.

With photovoltaic (PV) systems proliferating in the last few years due to the high prices of fossil fuels and pollution issues, among others, it is extremely important to monitor the efficiency of these plants and optimize the energy production process. This will also result in improvements related to the maintenance and security of the installation. In order to do so, the main parameters in the plant must be continuously monitored so that the appropriate actions can be carried out. This monitoring should not only be carried out at a global level, but also at panel-level, so that a better understanding of what is actually happening in the PV plant can be obtained. This paper presents a system based on a wireless sensor network (WSN) that includes all the components required for such monitoring as well as a power supply obtaining the energy required by the sensors from the photovoltaic panels. The system proposed succeeds in identifying all the nodes in the network and provides real-time monitoring while tracking efficiency, features, failures and weaknesses from a single cell up to the whole infrastructure. Thus, the decision-making process is simplified, which contributes to reducing failures, wastes and, consequently, costs.