Radiofrequency Energy Research Articles

Renal denervation for the treatment of hypertension and kidney disease.

Hypertension is a condition characterized by increased sympathetic activity and the autonomic nervous system. Resistant hypertension, a condition with a prevalence of 10% to 20% in the general hypertensive population, is more likely to experience poor outcomes and adverse cardiovascular events. Renal sympathetic denervation (RDN), a minimally invasive, catheter-based percutaneous intervention, has been considered for treating this condition. Clinical trials have used various catheters, such as the Symplicity Spyral catheter, Vessix Renal Denervation system, and Paradise endovascular ultrasound renal denervation system. After the first randomized clinical trials examining the effectiveness and safety of RDN for lowering blood pressure in hypertensive patients, new clinical trials have used various catheters based on radiofrequency, such as the Spyral catheter, Vessix Renal Denervation system, or based on radiofrequency as the Paradise endovascular ultrasound renal denervation system. Positive results on this trials have shown that endovascular RDN (radiofrequency energy or high focused ultrasound energy) could be considered as a treatment option for uncontrolled resistant hypertension. Therefore, endovascular RDN (radiofrequency energy or high focused ultrasound energy) could be considered as a treatment option for uncontrolled resistant hypertension, which can be considered as an alternative to increasing medication. Nevertheless more data are needed, mainly in cardiovascular outcomes. RDN should be performed in experienced and specialized centers with a multidisciplinary team, and the benefits and risks of RDN should be addressed in a shared-decision-making process.

Optimization of high-power short duration catheter radiofrequency ablation for pulmonary veins isolation in patients with artiral septial defect

Objective ‒ to perform the analysis and biophysical substantiation of a new technique of catheter radiofrequency ablation (RFA) with high power and short duration based on mathematical modeling of own clinical data of the electro-thermodynamic effect of RFA on the myocardium; to investigate the morphological characteristics of the myocardium in different areas of the atrium and to determine the morphometric parameters of the display on the electroanatomical model of the heart of the ablation zone in the EnSite Precision navigation system, necessary for effective and safe high-power and short-duration RFA.Materials and methods. Clinical studies were performed in Amosov National Institute of Cardiovascular Surgery NAMS of Ukraine. Specialized high-tech medical equipment was used for the objectivity of clinical data obtained and used in the work. Morphological characteristics of the myocardium (thickness of the wall of the left atrium, distance from the back wall of the heart to the esophagus, diameters of the pulmonary veins) were evaluated on the computed tomography images of the heart of the patients, which were obtained in the radiology department on a Toshiba device (Japan) using a spiral scanning. The morphometric parameters of the ablation zone, which were later used to evaluate the effectiveness of RFA and which formed the basis of standardized protocols for the operation, were determined for display on the electro-anatomical maps of the patients' hearts in the EnSite Precision system (Abbott, USA). Biophysical substantiation of the RFA technique with high power and short duration was performed using mathematical modeling of the electro-thermodynamic effect of RFA on the myocardium and own clinical data in the Comsol Multiphysics automated simulation of biophysical processes.Results. It is proposed for a group of patients with combined atrial fibrillation with an atrial septal defect to perform RFA using a new ablation technique with high power and short duration at one point of application of radio frequency energy. Achieving transmurality of ablation in a shorter time makes it possible to hold the electrode more precisely and stably in this area when isolating the pulmonary veins in a complex geometry and without support for the electrode in case of a defect. The morphological characteristics of the myocardium were studied and the morphometric parameters of the display on the electroanatomical heart model of the ablation zone, necessary for effective and safe RFA, were determined. These include: the diameter of the point-label of radiofrequency ablation on the anatomical model of the heart, which must correspond to the real data of the size of the destruction; the percentage of overlap of RFA points for the formation of an effective transmural line; estimated number of ablation points to standardize the evaluation of the effectiveness of the procedure.Conclusions. The conducted research made it possible to solve the current problems of catheter radiofrequency ablation in patients with atrial fibrillation and atrial septal defect, namely to increase the efficiency and safety of pulmonary vein isolation. Transmurality and integrity of the isolating line was achieved due to the determined morphological characteristics of the myocardium and the calculated morphometric parameters of the ablation zone. The obtained data are adapted to a real display visible to the surgeon on the electro-anatomical map of the heart in the EnSite Precision navigation system. This system is actively used in clinical practice, but it was necessary to optimize the clinical protocols of RFA with high power and short duration, which was achieved as a result of this work.

A multi-frequency and multi-mode metasurface energy harvester for RF energy harvesting

Metasurface energy harvesters (MEHs) lessen the dependence of wireless communication devices on batteries or other external power sources by capturing untapped electromagnetic energy in the surroundings. In this paper, we propose a multi-frequency and multi-mode microwave metasurface for efficient radio frequency (RF) and microwave energy harvesting. The MEH is comprised of a sub-wavelength resonant ring array, which can harvest RF energy in both Wi-Fi and 5 GHz bands. A feeding network is designed to integrate the TE and TM wave energy collected by the MEH into two separate networks that each gather AC energy and deliver them to the resistive loads. In terms of the simulation’s results, the efficiency of energy harvesting at frequencies of 2.4 GHz, 3.1 GHz, as well as 3.6 GHz is 91.3%, 88.9%, and 73.9%, specifically. We manufactured a 6 × 6 array sample and conducted experiments utilizing a microwave anechoic chamber. The simulation results and results from experiments were approximately identical. The proposed design has potential applications in various fields, such as efficient wireless energy harvesting systems, self-powered devices, which has a significant potential on the environment and the energy sector by reducing carbon emissions and reducing reliance on non-renewable energy sources.

Energy Harvesting for Wireless IoT Use Cases: A Generic Feasibility Model and Tradeoff Study

A battery-less IoT offers a sustainable alternative to battery-powered IoT devices, which produce billions of dead batteries every year. Devices are instead powered by a small supercapacitor, which is recharged by a renewable energy source. However, since IoT devices are often characterized by intermittent periods of high energy consumption followed by periods of reduced activity, conventional average energy consumption models can not be used to assess if an IoT devices can be powered by energy harvesters. Therefore, this paper presents an alternative feasibility evaluation approach that focuses on modeling the worst-case periods with peak energy consumption and short idle times, which pose the highest constraints on the capacitor’s behavior. This approach simplifies the characterization of the wireless technology energy consumption as these worst-case periods can be determined by a few parameters. The methodology is then applied to combinations of popular IoT technologies (LoRaWAN, BLE Mesh, and 6TiSCH) and energy sources (solar, kinetic, and radio frequency energy) for two common IoT use cases. We show that the proposed parameters can be successfully extracted with power measurements for different network configurations and that the Power Management Unit configuration has a non-negligible impact on the communication requirements. Finally, we discuss how to apply the model to other technologies and other use cases.

New conception of 3×4 circularly polarized antenna patch network for RF energy harvesting at 2.45 GHz

This paper presents a developed design of a 3×4 circular polarization microstrip antenna patch array whose its resonance frequency is 2.45 GHz in the ISM band. This array is printed on a FR4 substrate of 1.58 mm thickness with a dielectric permittivity of 4.4. The basic antenna patch is a square shape inserted by a rectangular slot inclined positioned diagonally at the center to achieve circular polarization. In addition, a triangular-shaped slit is added at each of the four corners of the patch. The antenna array performance is tested numerically using two different software packages, CST MWS and HFSS. The antenna’s array size is compacted to a 22.7 cm×13.5 cm. The simulated results give good performance results in terms of return loss and gain; directivity is found to be 9.66 dBi at 2.45 GHz; the axial ratio value is 1.69 dB; and total efficiency is about 95.55% at 2.45 GHz. Then, the simulated results obtained by these two programs are in good agreement, which makes this proposed array design very suitable for radio frequency energy harvesting and its various applications to power supply different devices in a clean way for our environment.

Cryothermal energy demonstrates shorter ablation time and lower complication rates compared with radiofrequency in surgical hybrid ablation for recurrent ventricular tachycardia

Recurrent ventricular tachycardia (VT) after prior endocardial catheter ablation(s) presents challenges in the setting of prior cardiac surgery where percutaneous epicardial access may not be feasible. The purpose of this study was to compare the outcomes of cryothermal vs radiofrequency ablation in direct surgical epicardial access procedures. We performed a retrospective study of consecutive surgical epicardial VT ablation cases. Surgical cases using cryothermal vs radiofrequency ablation were analyzed and outcomes were compared. Between 2009 and 2022, 43 patients underwent either a cryothermal (n = 17) or a radiofrequency (n = 26) hybrid epicardial ablation procedure with direct surgical access. Both groups were similarly matched for age, sex, etiology of VT, and comorbidities with a high burden of refractory VT despite previous endocardial and/or percutaneous epicardial ablation procedures. The surgical access site was lateral thoracotomy (76.5%) in the cryothermal ablation group compared with lateral thoracotomy (42.3%) and subxiphoid approach (38.5%) in the radiofrequency group, with the remainder in both groups performed via median sternotomy. The ablation time was significantly shorter in those undergoing cryothermal ablation vs radiofrequency ablation (11.54 ± 15.5 minutes vs 48.48 ± 23.6 minutes; P < .001). There were no complications in the cryothermal ablation group compared with 6 patients with complications in the radiofrequency group. Recurrent VT episodes and all-cause mortality were similar in both groups. Hybrid surgical VT ablation with cryothermal or radiofrequency energy demonstrated similar efficacy outcomes. Cryothermal ablation was more efficient and safer than radiofrequency in a surgical setting and should be considered when surgical access is required.

2.4 GHz Rectifier Antenna for Radiofrequency-based Wireless Power Transfer: Recent Developments, Opportunities, and Challenges

The use of radio frequency (RF) energy for wireless power transfer (WPT) has gained significant attention in recent years due to its potential for powering electronic devices without the need for wires or batteries. A key component of RF-based WPT systems is the rectenna, which converts RF energy into usable DC power. This article provides an overview of recent developments, opportunities, and challenges in the design of 2.4 GHz rectennas for RF-based WPT applications. We have searched major online libraries extensively for studies regarding the 2.4 GHz rectenna. As a result, 35 high-quality studies published between 2010 and 2023 were gathered. In the discussion section, we begin by presenting the basic principles of rectenna design and the key parameters that affect its performance, such as the antenna characteristics, rectifier capabilities, and nonlinearity properties of the rectifier. We then highlighted recent advancements in rectenna design, including novel approaches for improving efficiency and power transfer capability, such as the involvement of hybrid solar cell-rectenna structures, transistor-based rectifiers, and bridge rectifiers. Finally, the article concludes by identifying future opportunities, research directions, and open challenges in the design and optimization of rectennas for RF-based WPT, including the development of compact, low-cost, and high-performance rectennas for a wide range of applications. Overall, this article provides a comprehensive overview of the state-of-the-art of 2.4 GHz rectenna design for RF-based WPT and highlights the exciting opportunities and challenges for this rapidly growing field.

Advancing 5G Connectivity: A Comprehensive Review of MIMO Antennas for 5G Applications

The review focuses on the emergence of 5G wireless communication and the need for multiple-input multiple-output antennas to support high-speed communication systems. The article discusses the advantages of MIMO antennas, including increased channel capacity and the ability to focus radio frequency energy on specific users. However, the challenges of creating compact MIMO antennas with ideal isolation are addressed, including short wavelengths, connection losses, constrained bandwidth, and path losses in the millimeter-wave range. Design techniques and methods to enhance the performance of conventional antennas for 5G applications are discussed, along with potential solutions for upcoming challenges. The article provides an overview of MIMO antennas for 5G applications, covering frequency bands, system architecture, advantages, challenges, advancements, performance enhancement techniques, design techniques, and state-of-the-art developments.

Atrial fibrillation progression after cryoablation vs. radiofrequency ablation: the CIRCA-DOSE trial.

Atrial fibrillation (AF) is a chronic progressive disorder. Persistent forms of AF are associated with increased rates of thromboembolism, heart failure, and death. Catheter ablation modifies the pathogenic mechanism of AF progression. No randomized studies have evaluated the impact of the ablation energy on progression to persistent atrial tachyarrhythmia. Three hundred forty-six patients with drug-refractory paroxysmal AF were enrolled and randomly assigned to contact-force-guided RF ablation (CF-RF ablation, 115), 4 min cryoballoon ablation (CRYO-4, 115), or 2 min cryoballoon ablation (CRYO-2, 116). Implantable cardiac monitors placed at study entry were used for follow-up. The main outcome was the first episode of persistent atrial tachyarrhythmia. Secondary outcomes included atrial tachyarrhythmia recurrence and arrhythmia burden on the implantable monitor. At a median of 944.0 (interquartile range [IQR], 612.5-1104) days, 0 of 115 patients (0.0%) randomly assigned to CF-RF, 8 of 115 patients (7.0%) assigned to CRYO-4, and 5 of 116 patients (4.3%) assigned to CRYO-2 experienced an episode of persistent atrial tachyarrhythmia (P = .03). A documented recurrence of any atrial tachyarrhythmia ≥30 s occurred in 56.5%, 53.9%, and 62.9% of those randomized to CF-RF, CRYO-4, and CRYO-2, respectively; P = .65. Compared with that of the pre-ablation monitoring period, AF burden was reduced by a median of 99.5% (IQR 94.0%, 100.0%) with CF-RF, 99.9% (IQR 93.3%-100.0%) with CRYO-4, and 99.1%% (IQR 87.0%-100.0%) with CRYO-2 (P = .38). Catheter ablation of paroxysmal AF using radiofrequency energy was associated with fewer patients developing persistent AF on follow-up.

An Optimized and Highly Efficient Low Power RF Energy Harvesting System with Current Boost Technique Designed using 45 nm Technology

One of the most significant areas of research is looking for new energy sources and the best way to use them for sustainable applications. A viable approach to using radio frequency energy from environmental sources to power wireless devices is Radio Frequency Energy Harvesting (RFEH). However, the design of a rectifier, which is a crucial component of a RFEH system, presents several inherent difficulties. This paper presents a unique transmission gate-based rectifier design that is further improved with a simplified, novel current boost mechanism for efficient RFEH operation. A standard process technology node with a 45-nm pitch was used to simulate the analytical model. Particle Swarm Optimization (PSO) and Genetic Algorithm (GA), two bio-inspired algorithms, are adopted to optimize different device and circuit parameters of the rectifier so as to obtain the best possible performance. The proposed architecture performs better than contemporary approaches, as validated with different performance parameters. At a higher frequency band and with a negligibly low power consumption of 110nW, it offers 65% power conversion efficiency (PCE) at −20dbm, followed by PCEs of 80% at −15 dBm and 96% at −10 dBm. Eight MOSFETs and two passive components with optimized values are used in the circuit, which reduces the design area and lowers the cost. By raising the power level, the associated converter makes it practically usable for applications like a standalone wireless communication node or a drone-based relay. The designed system is completely batteryless and is capable of providing uninterrupted and consistent power to the intended node.

Nonorthogonal multiple access multiple input multiple output communications with harvested energy: Performance evaluation

AbstractThis paper demonstrates improved throughput and energy efficiency of wireless communications by exploiting nonorthogonal multiple access (NOMA), multiple input–multiple output (MIMO), and radio frequency energy harvesting (EH) technologies. To assess the performance of NOMA MIMO communications with EH (MMe), we consider the nonlinear characteristics of EH devices and propose explicit expressions for throughput and outage probability. Based on our results, the system performance is significantly mitigated by EH nonlinearity and is considerably improved by increasing the number of antennas. Additionally, by appropriately adjusting the system parameters, our NOMA MMe innovation can avert complete outages while optimizing system performance. Moreover, the results demonstrate the superiority of the NOMA MMe over its orthogonal multiple access MMe counterparts.

A multiband radio-frequency energy harvester for self-powered biosensor

This paper presents a novel nano-structure of radio frequency (RF) to direct current (DC) converter for the energy control unit in the biosensor. It is based on the Graëtz Bridge supplied with three-phase power (DP3). This circuit can be considered as the result of the proper combination of a common anode assembly and a common cathode assembly. In fact, the same three-phase converter structure was kept. The diodes have been replaced by six NMOS transistors connected in diodes. A number of capacitors have been added for each stage to boost voltage. The benefit of using this type of circuit is to obtain a powerful DC output signal with the smallest number of stages. The proposed architecture also enables MOS transistors to be driven by external 2.45 GHz voluntary signals originating from the implant's personal assistant. This would allow avoiding the use of transistor control circuits which are already power-consuming. For more power, the proposed converter receives two more involuntary global system for mobile signals (GSM) with 900 MHz and 1800 MHz frequencies bands in order to take advantage of the ambient energy. The proposed RF-DC converter efficiency reaches 62.8% for an input power equal to 10 dbm.

Effect of radio frequency energy on buckwheat quality: An insight into structure and physicochemical properties of protein and starch

Radio frequency (RF) heating as an emerging technology is widely used to improve cereal-based food quality. To further investigate effects of RF treatment on buckwheat quality, structures and physicochemical properties of protein and starch in buckwheat were evaluated under various temperatures (80, 90, and 100 °C) and holding times (0, 5, and 10 min). Results showed that protein-starch complexes were reaggregated with the increases of RF heating temperature and time, as well as the values of R1047/1022, crystallinity, random coil, and α-helix significantly decreased, and the values of β-sheet obviously increased. Moreover, viscosities and rheological properties of buckwheat were reduced by the raised RF treatment intensity. Besides, the RF processing had a mostly positive effect on swelling power at low temperature of 30 °C, but contrary effect at high temperatures of 60 °C and 90 °C. However, changes of water solubility index, emulsifying capacity, and emulsion stability depended on the RF processing intensity. These results of the study suggested that buckwheat quality was affected by multiple RF treatment conditions, which can be tailored to develop a RF process having the potential to improve the function of buckwheat flour.

Discussion to: Septal myectomy for hypertrophic obstructive cardiomyopathy using a pulsed radiofrequency energy soft tissue dissection instrument

Discussion to: Septal myectomy for hypertrophic obstructive cardiomyopathy using a pulsed radiofrequency energy soft tissue dissection instrument

Radiofrequency energy in the treatment of erectile dysfunction-a novel cohort pilot study on safety, applicability, and short-term efficacy.

The erectile mechanism depends, in part on the intactness of the collagen components in the penis. As such, impaired collagen may have a deleterious effect on erectile function. Radiofrequency energy has been shown to renew and restore spatial structural arrangement of collagen fibers; therefore, treatment of erectile dysfunction with radiofrequency could lead to anatomical and physiological changes at the penile tissue level and could lead to improvement in the erectile mechanism. We conducted this study to assess the effect of radiofrequency treatment on erection quality. We evaluated the safety, applicability, and efficacy of a self-applied, handheld, low-intensity radiofrequency device (Vertica®) in men with moderate and mild-to-moderate organic erectile dysfunction. The treatment protocol consisted of 12 treatments (twice a week during the 1st month, and once a week during the 2nd month), and each participant treated himself individually. Treatment outcomes were evaluated using the International Index of Erectile Function, Erection Hardness Scale, Erectile Dysfunction Index of Treatment Satisfaction, Benefit, Satisfaction & Willingness to continue, Quality of Erection Questionnaire, Sexual Quality of Life questionnaires and specific questions addressing side effects and ease of use. Twenty-eight out of 32 men (mean age 59.5 ± 9.8, range: 41-78 years) completed a one-month follow-up after treatment. Mean International Index of Erectile Function (43.7. ± 7.8 vs. 60.9 ± 10.8, p < 0.01), International Index of Erectile Function -Erection Function domain (16.8 ± 3.1 vs. 24.4 ± 4.4, p < 0.001), and Erection Hardness Scores (2.2 ± 0.8 vs. 3.2 ± 0.5, p = 0.01) were all significantly improved. Fifty percent of patients achieved normal erectile function parameters according to the International Index of Erectile Function -Erection Function domain score >25. High mean scores were achieved in the Erectile Dysfunction Index of Treatment Satisfaction (76.8 ± 20.3), Benefit, Satisfaction & Willingness to continue (4.83 ± 1.1), Quality of Erection Questionnaire (73.4 ± 23.8), and Sexual Quality of Life (67 ± 29.4) questionnaires. No side effects were reported and participants rated the device as very comfortable, simple, and easy to operate.

High-power short-duration catheter ablation of atrial fibrillation: is it really a new era? Comparison between new and old radiofrequency contact force-sensing catheters.

The clinical performance of high-power, short-duration (HPSD) pulmonary vein isolation (PVI) with the novel flexible tip TactiFlex™ (TFSE) catheter, as compared to standard-power, long-duration (SPLD) PVI using the TactiCath™ (TCSE) catheter among patients undergoing catheter ablation (CA) of atrial fibrillation (AF) is currently unknown. We conducted a prospective, observational, single-centre study including 40 consecutive patients undergoing PVI for paroxysmal/persistent AF, using HPSD ablation with the novel TFSE catheter (HPSD/TFSE group). Based on propensity score-matching, forty patients undergoing SPLD PVI with the TCSE catheter were identified (SPLD/TCSE group). In the HPSD/TFSE group, RF lesions were performed by delivering 40-50 W for 10-20s, while in the SPLD/TCSE group, RF power was 30-35 W, targeting a lesion size index (LSI) of 4.0-5.5. The co-primary study outcomes were time required to complete PVI and first pass isolation (FPI). PVI was achieved in 100% of patients in both groups, and no major adverse events were observed. Remarkably, PVI time was shorter in the HPSD/TFSE, compared to the SPLD/TCSE group(9 [7-9] min vs. 50 [37-54] min; p < 0.001), while FPI rate was non-significantly higher in the former group(91% [146/160] vs 83% [134/160]; p = 0.063). Shorter procedural (108 [91-120] min vs. 173 [139-187] min, p < 0.001), total RF (9 [7-11] min vs. 43 [32-53] min, p < 0.001), fluoroscopy times(15 [10-19] min vs. 18 [13-26] min, p = 0.014), and lower DAP (1461 [860-2181] vs. 7200 [3400-20,800], p < 0.001) were recorded in the HPSD/TFSE group. A higher average impedance drop was obtained with HPSD/TFSE CA(17[17-18]Ω vs. 16 [15-17] Ω, p < 0.001). In our initial clinical experience, HPSD PVI with the TFSE catheter proved faster than SPLD PVI with the TCSE catheter, at least equally effective in terms of FPI, and it was associated with greater impedance drop.

Performance analysis and optimization of multiple IIoT devices radio frequency energy harvesting NOMA mobile edge computing networks

In this day and age, the Industrial Internet of Things (IIoT) has been considered to revolutionize industrial manufacturing by capturing and accessing massive data sources with incredible speed and efficiency than before. Combined with it, Mobile Edge Computing (MEC) is a comprehensive Digital Transformation tendency to solve the problems Cloud computing faces. However, the fundamental challenges of energy and latency make deploying IIoT MEC networks difficult. Accordingly, this paper considers the efficient design of time allocation for successful computation probability (SCP) maximization for multiple energy-constrained mobile devices (MD) and multiple antennas access point (AP) in uplink radio frequency energy harvesting (RF EH) non-orthogonal multiple access (NOMA) IIoT network. Specifically, multiple MDs need to receive the energy and compute support of a MEC server placed in a multiple antenna wireless AP to complete the task immediately. Accordingly, a four-phase communication protocol is proposed to ensure system performance. The system follows the cluster head (CH) scheme based on the channel state information (CSI) to harvest RF energy from the AP. To ensure the highest system performance, we propose two algorithms for determining the optimal EH time for two CHs: SCPM-GSS and SCPM-GA. In addition, we derive the closed-form expressions for the SCP of the system and each CH. Monte Carlo simulations are used to verify the results of the analysis. The numerical results demonstrate the effects of crucial system parameters of our proposed NOMA scheme with those of conventional orthogonal multiple access (OMA) schemes. Furthermore, the proposed optimization algorithms allow the system to avoid outages like the random parameters setting approach and improve the SCP by 3 to 30% compared to the fixed parameters set when the transmit power is low and medium.

Progress in atrial fibrillation ablation during 25 years of Europace journal.

The first edition of Europace journal in 1999 came right around the time of the landmark publication of the electrophysiologists from Bordeaux, establishing how elimination of ectopic activity from the pulmonary veins (PVs) resulted in a marked reduction of atrial fibrillation (AF). The past 25 years have seen an incredible surge in scientific interest to develop new catheters and energy sources to optimize durability and safety of ablation, as well as study the mechanisms for AF and devise ablation strategies. While ablation in the beginning was performed with classic 4 mm tip catheters that emitted radiofrequency (RF) energy to create tissue lesions, this evolved to using irrigation and contact force (CF) measurement while increasing power. Also, so-called single-shot devices were developed with balloons and arrays to create larger contiguous lesions, and energy sources changed from RF current to cryogenic ablation and more recently pulsed field ablation with electrical current. Although PV ablation has remained the basis for every AF ablation, it was soon recognized that this was not enough to cure all patients, especially those with non-paroxysmal AF. Standardized approaches for additional ablation targets have been used but have not been satisfactory in all patients so far. This led to highly technical mapping systems that are meant to unravel the drivers for the maintenance of AF. In the following sections, the development of energies, strategies, and tools is described with a focus on the contribution of Europace to publish the outcomes of studies that were done during the past 25 years.

The use of radiofrequency in equine orthopedic surgery.

The use of radiofrequency energy (RFE) has become increasingly popular in equine orthopedic surgery in recent years, particularly for the debridement of cartilage lesions and soft tissue resection. However, despite considerable advancements in the technology, the safety and efficacy of RFE have continued to be questioned. While studies investigating the use of RFE for chondroplasty in the equine population are lacking, there is an abundance of research studies in the human literature assessing its effect on healthy chondrocytes, and researchers are seeking to develop guidelines to minimize collateral damage. This review article provides a concise and thorough summary of the current use of RFE in equine orthopedics, in addition to discussing the recent evidence surrounding its use for chondroplasty in both the human and equine populations.

Research on Resource Allocation Strategies for Wireless Powered Sensor Network

Wireless powered sensor network (WPSN) solves the problem of difficult battery replacement of sensor nodes in some environments. The unreasonable distribution of network resources in the energy transmission environment will lead to a sharp decline in the energy collected by sensor nodes, reduce the network life, and cause resource waste. In this paper, by introducing hybrid relay nodes to transmit energy to passive terminals and forward terminal information, the distance between passive terminals and final receiving nodes of information is reduced, and the contradiction between passive terminals’ data transmission requirements and “double path loss” of radio frequency energy transmission in WPSN is alleviated. At the same time, in the relay-powered WPSN, the life span of the relay node is equal to the life span of the whole network. This paper studies the energy efficiency transmission scheme of the relay node to maximize the energy utilization efficiency of the relay node and improve the life span of the WPSN.