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This study investigates the use of atomic layer deposition (ALD) to mitigate multipacting phenomena inside superconducting radio frequency cavities used in particle accelerators while preserving high quality factors in the 1010 range. The unique ALD capability to control the film thickness down to the atomic level on arbitrary complex shape objects enables the fine-tuning of TiN film resistivity and total electron emission yield (TEEY) from coupons to devices. This level of control allows us to adequately choose a TiN film thickness that provides both high resistivity to prevent Ohmic losses and a low TEEY to mitigate multipacting for the application of interest. The methodology presented in this work can be scaled to other domains and devices subject to RF fields in vacuum and sensitive to multipacting or electron discharge processes with their own requirements in resistivities and TEEY values. [ABSTRACT FROM AUTHOR]

In this paper, a sandwich structure metamaterial was designed, in which the substrate is radio frequency (RF) F4B, and the metal pattern of copper is prepared by the substrate on both sides. Analyzed the transmission of the structure, and the quad-band and reciprocal electromagnetically induced transparency (EIT)-like phenomena of the structure were obtained. The physical mechanism of the EIT-like phenomenon was explained by the electric field distribution. Discussing the size of the structure, the influence of structure parameters on EIT-like phenomena was further illustrated. By comparing the measured results with the calculated results in a microwave anechoic chamber, the results are in good agreement. This structure has potential applications in multi-band filtering, sensing, and other fields. [ABSTRACT FROM AUTHOR]

The evolution of nuclear spin state populations is investigated for the case of a 13C2-labeled triyne in solution, for which the near-equivalent coupled pairs of 13C nuclei experience cross-correlated relaxation mechanisms. Inversion-recovery experiments reveal different recovery curves for the main peak amplitudes, especially when the conversion of population imbalances to observable coherences is induced by a radio frequency pulse with a small flip angle. Measurements are performed over a range of magnetic fields by using a sample shuttle apparatus. In some cases, the time constant TS for decay of nuclear singlet order is more than 100 times larger than the time constant T1 for the equilibration of longitudinal magnetization. The results are interpreted by a theoretical model incorporating cross-correlated relaxation mechanisms, anisotropic rotational diffusion, and an external random magnetic field. A Lindbladian formalism is used to describe the dissipative dynamics of the spin system in an environment of finite temperature. Good agreement is achieved between theory and experiment. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of volume traps intentionally introduced into a silicon-on-insulator (SOI) substrate by inserting a layer of polysilicon beneath buried oxide. In radio frequency applications, this type of substrate, referred to as trap-rich, is known to considerably reduce the generation of harmonics resulting from the parasitic non-linear charge dynamics introduced by the substrate handler under the buried oxide. This analysis focuses on a test vehicle in the form of an integrated coplanar waveguide on two types of substrates, namely, high-resistivity SOI substrates with and without a trap-rich layer. From a modeling point of view, a simulation methodology is implemented in order to convert the 3D simulation of the coplanar waveguide into a 2D treatment that takes into account the wave propagation effect associated with the distributed nature of the transmission line. As a first step, this modeling strategy is implemented to reproduce the effect of increasing substrate resistivity on 2nd and 3rd harmonic reductions, leading to an excellent agreement with experimental data. Building on this validation of the simulation method, we have opted to simulate the non-linear response of the transmission line on the SOI trap-rich substrate by simplifying the trap distribution model. To avoid the adoption of unverified and strongly process-dependent trap distributions across the bandgap, a midgap monovalent trap density has been introduced, either acceptor or donor density. A monovalent density of acceptor traps with a concentration of 1016 cm−3 and a carrier lifetime of 0.1 ns has been shown to reproduce the experimental data very accurately with a substantial reduction in 2nd and 3rd harmonics. A detailed analysis of the displacement current waveforms explains the beneficial role of acceptor traps compared with donor traps. [ABSTRACT FROM AUTHOR]

Standing striations with a unique pattern have been observed in a radio-frequency-generated hydrogen plasma. The striation pattern consists of a sequence of closely spaced bright ring doublets and two types of dark gaps of different widths. The bright and dark regions in striations were spectroscopically resolved with the Balmer series and the Fulcher band emission lines of hydrogen. Temperatures in these fine structures were determined. In general, the wider dark gap has a higher excitation temperature than the nearby narrower ones in the striation pattern sequence. Bright regions are rotationally hotter than the adjacent dark ones. However, for vibrational temperatures, the trends are not so obvious. No clear pressure dependence of temperatures was observed in striations within the pressure range of maintaining stable standing striations in this work. In addition to optical emission spectroscopy, we used graphite granules as in situ probes for plasma conditions in different striation regions. The striated hydrogen plasma-treated graphite granules were analyzed with Raman spectroscopy. The observed hydrogen-graphite interaction was correlated with the measured temperatures and the fine structures of striations in a discharge tube. [ABSTRACT FROM AUTHOR]

The composition and ion energy distributions of the main ion species of an ion beam were recorded and analyzed. The RF-type broad beam ion source was operated with a mixture of CHF 3 and O 2. A plasma bridge neutralizer operating with Ar was employed for ion beam neutralization. The data were collected with an energy-selective mass spectrometer (ESMS). The mass spectrum showed numerous ion species, beginning with ionized molecules, dissociation products of the process gases and products from reactions with background gas and the plasma discharge vessel, and the extraction system. For a quantification of the ion beam composition, the mass dependent transmission functions for two ESMS were determined. The ion energy distributions show that, in comparison to operation with inert gases, there are additional slower ions present. These ions can be related to dissociation processes outside of the ion beam source. As a result of their typically lower etching yield, these slower ions affect the etching behavior. [ABSTRACT FROM AUTHOR]

The composition and ion energy distributions of the main ion species of an ion beam were recorded and analyzed. The RF-type broad beam ion source was operated with a mixture of CHF 3 and O 2. A plasma bridge neutralizer operating with Ar was employed for ion beam neutralization. The data were collected with an energy-selective mass spectrometer (ESMS). The mass spectrum showed numerous ion species, beginning with ionized molecules, dissociation products of the process gases and products from reactions with background gas and the plasma discharge vessel, and the extraction system. For a quantification of the ion beam composition, the mass dependent transmission functions for two ESMS were determined. The ion energy distributions show that, in comparison to operation with inert gases, there are additional slower ions present. These ions can be related to dissociation processes outside of the ion beam source. As a result of their typically lower etching yield, these slower ions affect the etching behavior. [ABSTRACT FROM AUTHOR]

This study explores how magnetization manipulation occurs in a flowing medium over a pipe geometry using nuclear magnetic resonance methods. In particular, the experimental conditions on radio frequency pulsing and the signal detection are studied in an ultra-low frequency regime of a few kilohertz. An analytical model of the magnetization preparation is presented, which calculates the magnetization distribution of an excited flowing segment. The effective flip angle distribution is mapped to simulate the temporal development of the magnetization in the segment. The simulation results are compared to the experimental data from a flow metering setup. As a result, the quantitative impact of the flow profile on the magnetic signal is shown. [ABSTRACT FROM AUTHOR]

Boron carbonitride (BCN) films containing hybridized bonds involving B, C, and N over wide compositional ranges enable an abundant variety of new materials, properties, and applications; however, their electronic performance is still limited by the presence of structural and electronic defects, yielding sluggish mobility and electrical conductivity. This work reports on mechanically stable BCN films and their corresponding optical and electronic properties. The ternary BCN films consisting of hybridized B–C–N bonds have been achieved by varying N2 flow by the radio frequency magnetron sputtering method. The BCN films show a bandgap value ranging from 3.32 to 3.82 eV. Hall effect measurements reveal an n-type conductivity with an improved hall mobility of 226 cm2/V s at room temperature for the optimal film. The n-BCN/p-Si heterojunctions exhibit a nonlinear rectifying characteristic, where the tunneling behavior dominates the injection regimes due to the density of defects, i.e., structural disorder and impurities. Our work demonstrates the tunable electrical properties of BCN/Si p–n diodes and, thus, is beneficial for the potential application in the fields of optics, optoelectronics, and electrics. [ABSTRACT FROM AUTHOR]

In nuclear magnetic resonance, long-lived coherences constitute a class of zero-quantum (ZQ) coherences that have lifetimes that can be longer than the relaxation lifetimes T2 of transverse magnetization. So far, such coherences have been observed in systems with two coupled spins with spin quantum numbers I = 1/2, where a term S 0 T 0 + T 0 S 0 in the density operator corresponds to a coherent superposition between the singlet S 0 and the central triplet T 0 state. Here, we report on the excitation and detection of collective long-lived coherences in AA′MM′XX′ spin systems in molecules containing a chain of at least three methylene (–CH2–) groups. Several variants of excitation by polychromatic spin-lock induced crossing (poly-SLIC) are introduced that can excite a non-uniform distribution of the amplitudes of terms such as S 0 S 0 T 0 S 0 S 0 T 0 , S 0 T 0 S 0 S 0 T 0 S 0 , and T 0 S 0 S 0 T 0 S 0 S 0 . Once the radio frequency fields are switched off, these are not eigenstates, leading to ZQ precession involving all six protons, a process that can be understood as a propagation of spin order along the chain of CH2 groups before the reconversion into observable magnetization by a second poly-SLIC pulse that can be applied to any one or several of the CH2 groups. In the resulting 2D spectra, the ω2 domain shows SQ spectra with the chemical shifts of the CH2 groups irradiated during the reconversion, while the ω1 dimension shows ZQ signals in absorption mode with linewidths on the order of 0.1 Hz that are not affected by the inhomogeneity of the static magnetic field but can be broadened by chemical exchange as occurs in drug screening. The ZQ frequencies are primarily determined by differences ΔJ between vicinal J-couplings. [ABSTRACT FROM AUTHOR]

Recent advances in Rydberg-atom electrometry detail promising applications in radio frequency communications. Presently, most applications use carrier frequencies greater than 1 GHz where resonant Autler–Townes splitting provides the highest sensitivity. This letter documents a series of experiments with Rydberg atomic sensors to collect and process waveforms from the automated identification system (AIS) used in maritime navigation in the very high frequency (VHF) band. Detection in this band is difficult with conventional resonant Autler–Townes based Rydberg sensing and requires a new approach. We show the results of a method called high angular momentum matching excited Raman (HAMMER), which enhances low frequency detection and exhibits superior sensitivity compared to the traditional AC Stark effect. From measurements of electromagnetically induced transparency in rubidium and cesium vapor cells, we show the relationship between incident electric field strength and observed signal-to-noise ratio and find that the sensitivity of the HAMMER scheme in rubidium achieved an equivalent single VHF tone sensitivity of 100 μ V / m / Hz . With these results, we estimate the usable range of the atomic vapor cell antenna for AIS waveforms given current technology and detection techniques. [ABSTRACT FROM AUTHOR]

The nitrogen-vacancy (NV) center is a promising candidate to realize practical quantum sensors with high sensitivity and high spatial resolution at room temperature and atmospheric pressure. In conventional high-frequency AC magnetometry with NV centers, the setup requires a pulse sequence with an appropriate time synchronization and strong microwave power. To avoid these practical difficulties, AC magnetometry using continuous-wave optically detected magnetic resonance (CW-ODMR) was recently demonstrated. That previous study utilized radio frequency (RF)-dressed states generated by the coherent interaction between the electron spin of the NV center and the RF wave. However, the drawback of this method is that the detectable frequency of the AC magnetic fields is fixed. Here, we propose and demonstrate frequency-tunable magnetic field sensing based on CW-ODMR. In the new sensing scheme, we obtain RF double-dressed states by irradiation with RF fields at two different frequencies. One creates the RF-dressed states and changes the frequency of the target AC field. The other is a target AC field that induces a change in the CW-ODMR spectrum by generating the RF double-dressed states through coherent interaction with the RF-dressed states. The sensitivity of our method is estimated to be comparable to or even higher than that of the conventional method based on the RF field with a single frequency. The estimated bandwidth is 7.5 MHz, higher than that of the conventional method using the RF-dressed states. Our frequency-tunable magnetic field sensor based on CW-ODMR paves the way for new applications in diamond devices. [ABSTRACT FROM AUTHOR]

Techniques for enhancing the signals arising from low-γ, insensitive (I) nuclei are central to solid-state nuclear magnetic resonance. One of the leading and best-established methods to sensitize these unreceptive species is Hartmann–Hahn cross polarization (HH-CP), a polarization transfer mechanism often executed under MAS. Herein, we explore the possibility of utilizing the 1H dipolar order created via adiabatic demagnetization in the rotating frame (ADRF), to enhance the unreceptive spins under MAS. It is found that an efficient polarization transfer via ADRF-CPMAS is not only possible but can exceed, at least in some instances involving plastic crystals, the efficiency of an optimized HH-CPMAS transfer. The experiment requires low radiofrequency nutation fields on both the 1H- and the I-spin channels, and displays unusual matching conditions that are reminiscent of the zero- and double-quantum matching conditions arising under CPMAS, albeit centered at zero frequency and demanding the simultaneous involvement of several spins. The origin of these multi-spin transfer processes is analytically derived and numerically simulated in predictions that compare well with experimental 13C and 15N results collected on model compounds at different spinning speeds. These derivations start from descriptions that depart from traditional thermodynamic arguments, and treat instead the ADRF processes in static and spinning solids on the basis of coherent evolutions. The predictions of these analytical derivations are corroborated by numerical simulations. The effects of additional factors, including chemical shift anisotropies, J-couplings, and radiofrequency inhomogeneities, are also theoretically and experimentally explored. [ABSTRACT FROM AUTHOR]

In this study, we developed a hybrid machine learning technique by combining appropriate classification and regression models to address challenges in producing high-mobility amorphous In2O3:Sn (a-ITO) films, which were fabricated by radio-frequency magnetron sputtering with a nitrogen-mediated amorphization method. To overcome this challenge, this hybrid model that was consisted of a support vector machine as a classification model and a gradient boosting regression tree as a regression model predicted the boundary conditions of crystallinity and experimental conditions with high mobility for a-ITO films. Based on this model, we were able to identify the boundary conditions between amorphous and crystalline crystallinity and thin film deposition conditions that resulted in a-ITO films with 27% higher mobility near the boundary than previous research results. Thus, this prediction model identified key parameters and optimal sputtering conditions necessary for producing high-mobility a-ITO films. The identification of such boundary conditions through machine learning is crucial in the exploration of thin film properties and enables the development of high-throughput experimental designs. [ABSTRACT FROM AUTHOR]

Radio frequencies in high-frequency (HF) and very high-frequency (VHF) bands (3–300 MHz) are challenging for Rydberg atom-based detection schemes, as resonant detection requires exciting atoms to extremely high energy states. We demonstrate a method for detecting and measuring radio frequency carriers in these bands via a controlled Autler–Townes line splitting. Using a resonant 18 GHz field, the absorption signal from Townes–Merritt sidebands created by a relatively low-frequency, non-resonant field can be enhanced. Notably, this technique uses a measurement of optical frequency separation of an avoided crossing to determine the amplitude of a non-resonant field. This technique also provides frequency-selective measurements of electric fields in the hundreds of MHz range with resolution of order 10 MHz. To show this, we demonstrate amplitude-modulated signal transduction on a MHz-range carrier. We further demonstrate reception of multiple tones simultaneously, creating a Rydberg "spectrum analyzer." [ABSTRACT FROM AUTHOR]

Epitaxial BaTiO3 integrated on Si or Si-on-insulator using off-axis radio frequency sputtering is a promising material platform for building electro-optic modulators based on the Pockels effect. Barium titanate thin films with c-axis orientation have been epitaxially integrated on silicon-on-insulator wafers. They exhibit excellent structural quality with Pockels coefficient (r33) > 130 pm/V and propagation loss <2 dB/cm. Our results show that off-axis sputtered BaTiO3 films yield electro-optic modulation similar to that of high-quality films grown by molecular beam epitaxy and that the material is suitable for implementation of low-power Mach–Zehnder interferometer electro-optic modulators integrated on silicon in a Z-cut configuration. [ABSTRACT FROM AUTHOR]

We demonstrate similarity rules for inductively coupled plasmas with thermohydrodynamic coupling effects using two-dimensional fluid simulations and theoretical analyses of the gas flow and heat transfer equations. The results confirm the validity of conventional similarity laws, e.g., the similarity relation for electron density, which can be violated by the nonlinear gas heating effects from exothermic and endothermic reactions. The nonlinear gas heating can obviously perturb the invariance of spatial distributions of the gas flow velocity, resulting in the electron density decreasing nonproportionally with different scaling factors. Adding an external heat source can mitigate the violation of the gas temperature scaling law, thus maintaining the validity of similarity relations to some extent. In addition, two kinds of scaling relations for excited-state argon atoms are identified with and without the consideration of nonlinear collisions. [ABSTRACT FROM AUTHOR]

The radio frequency ion thruster (RIT) is an electric propulsion device that utilizes radio frequency (RF) power to ionize propellants; thus, its performance is influenced by the frequency and matching network of the RF. In this study, an L&T type wide-range matching network was employed to experimentally investigate the performance of a miniature RIT with 4 cm diameter at different frequencies. The experimental results show that changing the matching parameters of the L&T network at the same frequency leads to changes in the effective quality factor and varying performances of the thruster; under similar effective quality factors, changing the frequency does not significantly affect the performance of the thruster; however, the plasma resistance exhibits frequency dependence. As the frequency increases, the effective collision frequency increases, leading to an increase in plasma resistance, which is beneficial for improving the performance of the thruster at high frequencies. Finally, a set of methods for quickly comparing the performance of RITs was summarized based on the effective quality factor. These research results are also instructive for improving the ionization of induction-coupled discharge devices of other sizes. [ABSTRACT FROM AUTHOR]

We investigate the sensitivity of co-linear three-photon electromagnetically induced transparency (EIT) in 133 Cs Rydberg atoms to radio frequency electric fields and compare against the conventional two-photon system. Specifically, we model the 4-level and 5-level atomic systems and compare how the transmission of the probe changes with different laser powers and RF field strengths. In this model, we define a sensitivity metric that relates to the current best experimental implementation and assumes photon shot noise limited detection. We find that the three-photon system boasts much narrower linewidths compared to the conventional two-photon EIT. These narrow line features, however, do not align with the regions of the best sensitivity. In addition to this, we calculate the expected sensitivity for the two-photon Rydberg sensor and find that the best achievable sensitivity is over an order of magnitude better than the current measured values of 5 μ Vm − 1 Hz − 1 / 2 . However, by accounting for additional noise sources in the experiment and the quantum efficiency of the photo-detectors, the values are in good agreement. [ABSTRACT FROM AUTHOR]

The growing demand for real-time ultraviolet (UV) monitoring calls for a simple, rapid, and low-cost strategy to prepare UV photodetectors (PDs). We prepare a wearable real-time UV PD based on hydrogenated titanium dioxide film synthesized by radio frequency atmospheric pressure plasma. The conductivity of our hydrogenated titanium dioxide is improved to 10.2 S cm−1, nine orders of magnitude higher than that of pristine titanium dioxide after 10 min plasma treatment. Plasma hydrogenation disrupts the surface crystal structure, introducing oxygen vacancies (OVs) that create self-doped titanium(III) and titanium(II) species. First-principles calculations indicate that the OVs raise the Fermi level of TiO2 and distort the lattice locally. Our optimized film has a distinctive periodic switching characteristic under intermittent illumination; its responsivity is good from 280 to 400 nm, peaking at 632.35 mA W−1 at 365 nm. The fabricated wearable sensor based on the optimized film effectively monitors the daily variation of ambient UV intensity in three typical weather types, transferring its data to a smartphone via Wi-Fi. [ABSTRACT FROM AUTHOR]

An asymmetric system consisting of two coupled radio frequency superconducting quantum interference devices (RF-SQUIDs) with general geometry as nonlinear macroscopic system with mutual inductance under the influence of a time-dependent external field has been investigated numerically. Due to the importance of mutual induction in the construction of such nonlinear asymmetric systems, the dependence of coupling coefficient on the frequency changes, the primary and secondary resonance amplitudes and also the anti-resonances in both squids have been investigated. By changing the geometry of the arrangement of squids, the dynamic behavior parameters of the system have been studied. The eigenvalues of this system have been found and by changing frequency, the stable and unstable states have been studied. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Case Presentation Intervention Results Conclusion Poly‐D,L‐lactic acid (PDLLA) is used for tear trough rejuvenation but can cause complications like nodular reactions. This report describes using a radiofrequency device to manage these nodules.A 42‐year‐old woman developed firm, non‐inflammatory nodules 3 weeks after receiving PDLLA (Juvelook) injections in the tear trough area. The nodules were firm and not associated with erythema or tenderness.The monopolar radiofrequency device was used directly on the nodules with 150 shots at an energy level 115 J, 28.75 J/cm². The treatment resulted in complete resolution of the nodules within 24 hours.The radiofrequency treatment effectively resolved the nodular reaction without recurrence, highlighting the device's compatibility with the unique structure of Juvelook's PDLLA.Radiofrequency therapy is effective for managing nodular reactions following PDLLA injections. Further research is needed to optimise protocols and improve the safety of biostimulator treatments in cosmetic procedures. [ABSTRACT FROM AUTHOR]

In this study, we investigated the capability of the Nakagami transformation to detect changes in vastus lateralis muscle-tendon stiffness (k) during dynamic (and intense) contractions. k was evaluated in eleven healthy males using the gold-standard method (a combination of ultrasound and dynamometric measurements) during maximal and sub-maximal voluntary fixed-end contractions of the knee extensors (20, 40, 60, 80, and 100% of maximum voluntary force), while Nakagami parameters were analysed using the Nakagami transformation during the same contractions. Muscle-belly behaviour was investigated by means of B-mode ultrasound analysis, while Nakagami parameters were obtained in post-processing using radiofrequency data. k was calculated as the slope of the force-muscle-belly elongation relationship. Three contractions at each intensity were performed to calculate the intra-trial reliability and the coefficient of variation (CV) of the Nakagami parameters. At all contraction intensities, high values of intra-trial reliability (range: 0.92–0.96) and low CV (<9%) were observed. k and Nakagami parameters increased as a function of contraction intensity, and significant positive correlations were observed between these variables. These data suggest that changes in mechanical properties (e.g., stiffness) at the muscle level could be investigated by means of Nakagami parameters. [ABSTRACT FROM AUTHOR]

Background: Pulsed radiofrequency (PRF) treatment targeting the greater occipital nerve (GON) has shown efficacy in treating various conditions. This double-blind, randomized controlled study aimed to evaluate the effects of combining PRF therapy with GON block (GONB) therapy in patients with chronic migraine. Methods: The study consisted of two groups: GONB and GONB + PRF, each comprising 16 patients with chronic migraine. Using 0.5-Hz sensorial stimulation, a 5-cm-long radiofrequency needle was inserted under ultrasound guidance in both groups. Subsequently, all patients received a GONB by administering 2 mL of 0.25% bupivacaine. In the GONB + PRF group, patients underwent 4 min of PRF at 42℃, whereas the GONB group did not receive any PRF treatment. Follow-up examinations were performed at 1, 2, 3 and 6 months after the procedure to evaluate the frequency and severity of migraine attacks, number of headache days, and analgesic consumption. Results: In the GONB + PRF group, the visual analog scale (VAS) score, number of migraine attacks, number of headache days, and analgesic consumption were significantly lower compared to the GONB group (P < 0.05). Significant decreases (60%) in mean VAS scores, number of migraine attacks, number of headache days, and consumption of analgesic medications were observed in the GONB + PRF group at the 1-, 2-, 3-, and 6-month follow-ups compared with the pre-treatment period (P < 0.05). Conclusions: The combination of GONB and PRF presents a promising new treatment option for patients with chronic migraine. This approach has demonstrated efficacy in minimizing analgesic use, decreasing the frequency of migraine attacks, reducing the number of headache days and decreasing the severity of migraine attacks. Trial Registration: NCT05464212. [ABSTRACT FROM AUTHOR]

Objective: The success rate of achieving seizure freedom after radiofrequency thermocoagulation surgery for patients with refractory focal epilepsy is about 20-40%. This study aims to enhance the prediction of surgical outcomes based on preoperative decisions through network model simulation, providing a reference for clinicians to validate and optimize surgical plans. Methods: Twelve patients with epilepsy who underwent radiofrequency thermocoagulation were retrospectively reviewed in this study. A coupled model based on model subsets of the neural mass model was constructed by calculating partial directed coherence as the coupling matrix from stereoelectroencephalography (SEEG) signals. Multi-channel time-varying model parameters of excitation and inhibitions were identified by fitting the real SEEG signals with the coupled model. Further incorporating these model parameters, the coupled model virtually removed contacts destroyed in radiofrequency thermocoagulation or selected randomly. Subsequently, the coupled model after virtual surgery was simulated. Results: The identified excitatory and inhibitory parameters showed significant difference before and after seizure onset (p < 0.05), and the trends of parameter changes aligned with the seizure process. Additionally, excitatory parameters of epileptogenic contacts were higher than that of non-epileptogenic contacts, and opposite findings were noticed for inhibitory parameters. The simulated signals of postoperative models to predict surgical outcomes yielded an area under the curve (AUC) of 83.33% and an accuracy of 91.67%. Conclusion: The multi-channel coupled model proposed in this study with physiological characteristics showed a desirable performance for preoperatively predicting patients' prognoses. [ABSTRACT FROM AUTHOR]

Background Aim Methods Conclusions Lasers and other energy‐based devices are increasingly becoming popular in aesthetic practice. Many centers employ doctors or technicians to perform these procedures where treating doctor and operating doctor may be different. Hence the need for standard operative protocols, to be followed while performing these procedures to avoid mistakes, complications and to get optimum results. In the current review article, group of doctors who have worked with these energy‐based devices over many years worked together and suggested the protocols to be followed for the most commonly used energy‐based procedures.To provide Standard operating protocols for the operator and staff to ensure, efficacy, safety, for the patient and for the devices.The following protocols have been drafted based on the best practices followed by the authors in their clinics and reflect their consensus opinion. The objective is to provide operating protocols in a standard format, which can be of use by practicing dermatologists and their staff. The protocols include both general guidelines for the laser room and specific protocols for different machines. The draft follows the following schema: General instructions for all the energy‐based devices. Specific protocols for different devices: Laser hair removal, fractional lasers, Q‐switched lasers, fractional microneedling radiofrequency and cryolipolysis. The protocols proposed help to maintain the uniformity and avoid complications. However, these instructions are generalized and not machine or lesion specific. There may be variations in the protocols depending on the treatment lesion and treating doctor as well as machine. [ABSTRACT FROM AUTHOR]

Integrated sensing and communications (ISAC) based on radio frequency (RF), merging the sensing and communication functionalities into a single platform, can effectively address the increasing demand for spectrums due to the proliferation of wireless devices. However, the ISAC commonly suffers from spectrum scarcity, high power consumption, and limited sensing capabilities. Here flexible self‐powered optical ISAC (O‐ISAC) is proposed and fabricated by preparing a high‐speed near‐infrared organic photodetector (NIR OPD) that exhibits a broad photodetection ranging from 300 to 1100 nm, specific detectivity over 1013 Jones, and −3 dB cutoff frequency over 1 MHz (λ = 1050 nm) in self‐powered mode, ranking as the fastest among self‐powered NIR OPDs in the region above 1000 nm. The device is fabricated by incorporating a narrow‐bandgap non‐fullerene acceptor BTPSV‐4Cl into the PCE‐10:BTPSV‐4F system to finely tune the film morphology and reduce trap states and energetic disorder. The semitransparent and regular NIR OPDs are integrated on one substrate to fabricate flexible O‐ISAC, realizing simultaneous accurate vital signs monitoring and high‐speed data transmission under ambient, sunlight, and NIR lighting conditions. It is envisioned that the proposed O‐ISAC will inspire a new generation of wireless technology to address RF limitations for emerging applications, such as intelligent healthcare, autonomous vehicles, and security. [ABSTRACT FROM AUTHOR]

Background: We discuss the diagnostic benefit of pulsed radiofrequency (PRF) of the dorsal root ganglion (DRG) in a case series of patients with different pathologies. We expand the diagnostic potential of DRG stimulation beyond paresthesia mapping by using DRG stimulation to help determine the role of the DRG in the patient's pain and narrow down the etiology. In some cases, DRG stimulation was also part of the treatment plan. Methods: Six patients underwent DRG radiofrequency as a diagnostic/therapeutic step before considering implantation of a DRG neurostimulator. First, patients underwent a basic bedside neurological evaluation. Next, an electrode was placed in the epidural space through the sacral hiatus or between vertebral laminae. Then, sensory stimulation was applied at 50 Hz and gradually increased from 0.1 V until the patient reported paresthesia or until a maximum intensity of 2 V was reached. Patients were asked to describe where the stimulation was felt and outline the anatomical area the paresthesia covered. Then a motor stimulation was applied at 2 Hz until muscle twitching was reported by the patient or observed by the physician. Results: The information obtained helped diagnose the type of lesion as principally preganglionic, ganglionic, or postganglionic. This information guided patient management. Conclusion: PRF of the DRG can provide valuable diagnostic information and is a useful step before ganglionic electrode implantation. In all cases, PRF of the DRG provided valuable diagnostic information and guided management options. [ABSTRACT FROM AUTHOR]

The noninvasive measurement and sensing of vital bio signs, such as respiration and cardiopulmonary parameters, has become an essential part of the evaluation of a patient's physiological condition. The demand for new technologies that facilitate remote and noninvasive techniques for such measurements continues to grow. While previous research has made strides in the continuous monitoring of vital bio signs using lasers, this paper introduces a novel technique for remote noncontact measurements based on radio frequencies. Unlike laser-based methods, this innovative approach offers the advantage of penetrating through walls and tissues, enabling the measurement of respiration and heart rate. Our method, diverging from traditional radar systems, introduces a unique sensing concept that enables the detection of micro-movements in all directions, including those parallel to the antenna surface. The main goal of this work is to present a novel, simple, and cost-effective measurement tool capable of indicating changes in a subject's condition. By leveraging the unique properties of radio frequencies, this technique allows for the noninvasive monitoring of vital bio signs without the need for physical contact or invasive procedures. Moreover, the ability to penetrate barriers such as walls and tissues opens new possibilities for remote monitoring in various settings, including home healthcare, hospital environments, and even search and rescue operations. In order to validate the effectiveness of this technique, a series of experiments were conducted using a prototype device. The results demonstrated the feasibility of accurately measuring respiration patterns and heart rate remotely, showcasing the potential for real-time monitoring of a patient's physiological parameters. Furthermore, the simplicity and low-cost nature of the proposed measurement tool make it accessible to a wide range of users, including healthcare professionals, caregivers, and individuals seeking to monitor their own health. [ABSTRACT FROM AUTHOR]

The rapid evolution of drone technology has introduced unprecedented challenges in security, particularly concerning the threat of unconventional drone and swarm attacks. In order to deal with threats, drones need to be classified by intercepting their Radio Frequency (RF) signals. With the arrival of Sixth Generation (6G) networks, it is required to develop sophisticated methods to properly categorize drone signals in order to achieve optimal resource sharing, high-security levels, and mobility management. However, deep ensemble learning has not been investigated properly in the case of 6G. It is anticipated that it will incorporate drone-based BTS and cellular networks that, in one way or another, may be subjected to jamming, intentional interferences, or other dangers from unauthorized UAVs. Thus, this study is conducted based on Radio Frequency Fingerprinting (RFF) of drones identified to detect unauthorized ones so that proper actions can be taken to protect the network's security and integrity. This paper proposes a novel method—a Composite Ensemble Learning (CEL)-based neural network—for drone signal classification. The proposed method integrates wavelet-based denoising and combines automatic and manual feature extraction techniques to foster feature diversity, robustness, and performance enhancement. Through extensive experiments conducted on open-source benchmark datasets of drones, our approach demonstrates superior classification accuracies compared to recent benchmark deep learning techniques across various Signal-to-Noise Ratios (SNRs). This novel approach holds promise for enhancing communication efficiency, security, and safety in 6G networks amidst the proliferation of drone-based applications. [ABSTRACT FROM AUTHOR]

The physical properties of lunar regolith are crucial for exploration planning, hazard assessment, and characterizing scientific targets at global and polar scales. The dielectric constant, a key property, offers insights into lunar material distribution within the regolith and serves as a proxy for identifying volatile-rich regoliths. Miniature radio frequency (Mini-RF) on the Lunar Reconnaissance Orbiter (LRO) provides a potential tool for mapping the lunar regolith's physical nature and assessing the lunar volatile repository. This study presents global and polar S-band Mini-RF dielectric signatures of the Moon, obtained through a novel deep learning inversion model applied to Mini-RF mosaics. We achieved good agreement between training and testing of the model, yielding a coefficient of determination (R2 value) of 0.97 and a mean squared error of 0.27 for the dielectric constant. Significant variability in the dielectric constant is observed globally, with high-Ti mare basalts exhibiting lower values than low-Ti highland materials. However, discernibility between the South Pole–Aitken (SPA) basin and highlands is not evident. Despite similar dielectric constants on average, notable spatial variations exist within the south and north polar regions, influenced by crater ejecta, permanently shadowed regions, and crater floors. These dielectric differences are attributed to extensive mantling of lunar materials, impact cratering processes, and ilmenite content. Using the east- and west-looking polar mosaics, we estimated an uncertainty (standard deviation) of 1.01 in the real part and 0.03 in the imaginary part of the dielectric constant due to look direction. Additionally, modeling highlights radar backscatter sensitivity to incidence angle and dielectric constant at the Mini-RF wavelength. The dielectric constant maps provide a new and unique perspective of lunar terrains that could play an important role in characterizing lunar resources in future targeted human and robotic exploration of the Moon. [ABSTRACT FROM AUTHOR]

Changes in spatio-temporal gait parameters and their variability during balance-challenging tasks are markers of motor performance linked to fall risk. Radio frequency (RF) sensors hold great promise towards achieving continuous remote monitoring of these parameters. To establish the concurrent validity of RF-based gait metrics extracted using micro-Doppler (µD) signatures and to determine whether these metrics are sensitive to gait modifications created by multidirectional visual perturbations. Fifteen participants walked overground in a virtual environment (VE) and VE with medio-lateral (ML) and antero-posterior (AP) perturbations. An optoelectronic motion capture system and one RF sensor were used to extract the linear velocity of the trunk and estimate step time (ST), step velocity (SV), step length (SL), and their variability (STV, SVV, and SLV). Intra-class coefficient for consistency (ICC), mean and standard deviation of the differences (MD), 95 % limits of agreement, and Pearson correlation coefficients (r) were used to determine concurrent validity. One-way repeated-measures analysis of variance was used to analyze the main and interaction effects of visual conditions. All outcomes showed good to excellent reliability (r>0.795, ICC>0.886). Average gait parameters showed good to excellent agreement, with values obtained with the RF sensor systematically smaller than the values obtained with the markers (MD of 0.001 s, 0.09 m/s, and 0.06 m). Gait variability parameters showed poor to moderate agreement, with values obtained with the RF sensor systematically larger than those obtained with the markers (MD of 1.9 %-3.9 %). Both measurement systems reported decreased SL and SV during ML perturbations, but the gait variability parameters extracted with the radar were not able to detect the higher STV and SLV during this condition. The radar µD signature is a valid and reliable method for the assessment of average spatio-temporal gait parameters but gait variability measures need to be viewed with caution because of the lower levels of agreement and sensitivity to ML visual perturbations. This work represents an initial investigation for the development of a low-cost system that will facilitate aging-in-place by providing remote monitoring of gait in natural settings. • A Radio Frequency (RF) sensor was used to estimate gait parameters. • A virtual reality headset was used to deliver visual perturbations while walking. • The RF sensor can estimate gait parameters with good to excellent reliability. • The RF sensor can estimate gait parameters with poor to excellent agreement. • The RF gait variability measures need to be viewed with caution. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this study was to investigate the multi‐scale structures, thermal, pasting, and textural properties of starch from different genotypes (dent and flint) of corn with varying moisture content (MC) (0.20, 0.25, and 0.30 kg kg−1 in dry basis) following radio frequency (RF) electromagnetic fields. As the MC increased, the amylose content in dent and flint corn starch rose from 14.60% to 19.70% and 14.80% to 24.63%, respectively, after the hot air (HA)‐RF treatment. With the increase in MC, the enhancement of starch–protein interaction and the change in starch molecule structure caused decreases in the crystallinity, short–range order structure, and enthalpy, while there were increases in the gelatinisation temperature, pasting viscosity, and textural properties of starch. The results showed that the RF treatment is an effective method for improving the processing performance of starch. Our data provide a foundation to expand the application of radio frequency in the food industry. [ABSTRACT FROM AUTHOR]

Summary: Freezing is a widely used method for preserving fresh strawberries, and selecting appropriate thawing technologies is crucial for obtaining high‐quality thawed strawberries. Radio frequency technology provides a promising method owing to its expeditious uniform heating mode with substantial penetration depth. This study investigated the effects of radio frequency thawing (RFT) using electrode gaps of 12, 14, or 16 cm on the quality attributes of frozen strawberries, comparing them with refrigerator thawing (RT) and microwave thawing (MWT). The results illustrated that strawberries thawed by RFT exhibited significantly lower firmness loss and higher levels of anthocyanins and ascorbic acid compared to RT and MWT methods. Specifically, strawberries thawed with a 12‐cm electrode gap under RFT showed faster thawing rates, increased phenolic content, and enhanced antioxidant activity. Overall, radio frequency technology shows great potential in enhancing the quality of thawed strawberries. [ABSTRACT FROM AUTHOR]

Objective: To assess the effectiveness and safety of treating erythematotelangiectatic rosacea using fractional radiofrequency (FRF). Methods: Twenty patients with a confirmed diagnosis of erythema capillaris rosacea were selected, and one side of each patient's face was randomly assigned to receive FRF treatments for three to six times, with an interval of 2 weeks between each treatment. VISIA, dermoscopy, and the Clinician's Erythema Evaluation Scale (CEA) were applied to evaluate the efficacy of the treatment before and after the treatment, to record the VAS scores and adverse reactions, and to conduct a patient satisfaction survey. Results: The characteristic counts and scores of red zone and porphyrin as assessed by VISIA test were significantly decreased, and the difference between the treated side and the pretreatment side was statistically significant (p < 0.05), and the efficacy of the treatment was statistically insignificant compared with the control side, except for the red zone and porphyrin which were statistically significant before and after the treatment (p > 0.05). By CEA score, the difference between the treated side after treatment and the control side was statistically significant (p < 0.05), and the difference between the treated side before and after treatment was statistically significant (p < 0.05); the difference between the control side before and after treatment was not statistically significant (p > 0.05). Dermatoscopic observation showed reduction in pore size, reduction of yellowish‐white and black horn plugs within the pores, lightening of the red background and thinning and blurring of the capillary structure on the treated side of the skin compared to the control side, and the skin on the treated side showed the above mentioned changes before and after the treatment as well. The mean pain score of the subjects was obtained by VAS score 3.67 ± 0.90. Adverse effects included mild edema, erythema, and microscopic crusting; no long‐term adverse effects were seen in all patients. The efficacy of FRF treatment was evaluated 1 month after the final treatment, and 85% of the subjects rated it as satisfactory, very satisfactory, and very satisfactory. Conclusion: FRF for the treatment of erythematous capillary dilatation rosacea is effective, safe, and suitable for clinical promotion. [ABSTRACT FROM AUTHOR]

In this paper, the performance of a dual-hop mixed radio frequency (RF)/underwater wireless optical communication (UWOC) system with amplifying and forwarding (AF) relaying is investigated. The diversity combining technology were combined with unifying Fisher-Snedecor ( $ \mathcal{F} $ F ), extended generalized- $ {\mathcal{K}} $ K (EGK), and $ \alpha - \mu $ α − μ distribution for atmospheric turbulence in foggy conditions to analyze the probability density function (PDF) of RF links. The UWOC link experiences mixed exponential generalized gamma (EGG) fading. By utilizing diversity combination methods and considering the statistical effects of atmospheric turbulence, random fog, and underwater turbulence, we derive the expression for the PDF of the RF/UWOC system. In addition, the tight asymptotic expression for the outage probability and average bit error rate under high signal-to-noise ratio (SNR) is provided. The analytical expressions are verified by Monte Carlo method, and the effects of channel number on RF/UWOC system performance under various atmospheric, underwater and weather conditions are demonstrated. [ABSTRACT FROM AUTHOR]

In the realm of Internet of Things (IoT) networks, Backscatter communication (BackCom) is a promising technique that allows devices to send data through the reflecting surrounding radio frequency (RF) signals. Integrating unmanned aerial vehicles (UAVs) with BackCom technology to establish UAV-assisted BackCom networks presents an opportunity to provide self-generated RF signals for backscatter devices, establishing self-sustaining data collection systems. This paper investigates directional UAV-assisted BackCom networks where UAVs are equipped with directional antennas, which differs from previous studies that mainly consider omni-directional antennas. To ensure the quality of Back- Com, we develop a theoretical model that analyzes the valid altitude range of UAVs, which is often ignored in previous studies. Based on the altitude range of UAVs, we then de-rive the throughput of directional UAV-assisted BackCom networks. Extensive simulations are conducted to verify our theoretical model, revealing correlations between the UAV altitude range, the throughput, directional antennas, and other key parameters. Results indicate that UAVs need to set the proper UAV altitude according to multiple parameters to ensure successful communication. In addition, adjusting the beamwidth of directional antennas can enhance both the altitude range of UAVs and the throughput of networks. [ABSTRACT FROM AUTHOR]

The integration of radar interference is an effective technical path to optimize radio frequency resources and realize directional interference. Radar interference integrated waveform design is a hot spot in radar interference integrated research. This paper presents an radar interference integrated waveform based on Zadoff-Chu sequence and orthogonal frequency division multiplexing (OFDM) architecture, and studies the waveform design and processing methods. The waveform uses OFDM as the modulation mode and time- frequency division multiplexing as the basic architecture. The frequency domain subcarriers are reasonably allocated and modulated through Zadoff-Chu and Mersenne-Twister sequences to achieve the integration of detection and interference functions. In signal processing, the first step in to separate the time and frequency of interference detection, and the second step in to conduct pulse compression and coherent processing, so as to achieve ranging and velocity measurement. Theoretical analysis and simulation test show that the proposed waveform has the advantages of high ratio of main lobe to side lobe of pulse compression, strong Doppler tolerance, flexible frequency alignment and strong interference randomness. [ABSTRACT FROM AUTHOR]

The impact of electrode spacing, power supply voltage, radio frequency, and gas pressure on capacitively coupled plasma discharge under both weak and strong magnetic fields is investigated by using a one-dimensional implicit particle-in-cell/Monte Carlo collision simulation. Simulation results indicate that under both weak and strong magnetic field conditions, plasma density increases with the increase in these discharge parameters. However, the principle of density increase under weak and strong magnetic field conditions is slightly different. The strong magnetic field plays a crucial role in strongly constraining electrons. Under weak magnetic field conditions, the mutual transition between stochastic heating and ohmic heating can be observed, while under strong magnetic field conditions, ohmic heating predominantly prevails. Furthermore, the simulation results also indicate that a strong magnetic field can effectively reduce the voltage threshold for the transition from the α mode to the γ mode. The strong magnetic field strongly confines secondary electrons near the sheath, allowing them to interact multiple times with the sheath and acquire higher energy, thereby making the γ mode more likely to occur. [ABSTRACT FROM AUTHOR]

Developing anode materials with high specific capacity and cycling stability is vital for improving thin‐film lithium‐ion batteries. Thin‐film zinc oxide (ZnO) holds promise due to its high specific capacity, but it suffers from volume changes and structural stress during cycling, leading to poor battery performance. In this research, we ingeniously combined polytetrafluoroethylene (PTFE) with ZnO using a radio frequency (RF) magnetron co‐sputtering method, ensuring a strong bond in the thin‐film composite electrode. PTFE effectively reduced stress on the active material and mitigated volume change effects during Li+ ion intercalation and deintercalation. The composite thin films are thoroughly characterized using advanced techniques such as X‐ray diffraction, scanning electron microscopy, and X‐ray photoelectron spectroscopy for investigating correlations between material properties and electrochemical behaviors. Notably, the ZnO/PTFE thin‐film electrode demonstrated an impressive specific capacity of 1305 mAh g−1 (=7116 mAh cm−3) at a 0.5C rate and a remarkable capacity retention of 82% from the 1st to the 100th cycle, surpassing the bare ZnO thin film (50%). This study provides valuable insights into using binders to stabilize active materials in thin‐film batteries, enhancing battery performance. [ABSTRACT FROM AUTHOR]

The unprecedented exposure of radiofrequency electromagnetic field (RF‐EMF) to humans from mobile communications raises serious public concern about the possibility of unexpected adverse health effects and has stimulated authorities to adopt precautionary exposure limits. These limits are distinctly different across countries, and the causes of these differences are unclear from the literature. This article is the first empirical analysis on the determinants of RF‐EMF exposure legislation, using a novel cross‐sectional database of 164 countries worldwide. The analysis shows that decentralization and mobile competition in countries with low mobile network deployment tend to promote more stringent RF‐EMF exposure limits across the dataset with 164 countries. In more decentralized countries, the regions had a greater influence on national legislation and could accommodate local demands with the advent of mobile technology in the 2000s. In contrast, decentralization and mobile competition in countries with high levels of mobile network deployment tend to relax RF‐EMF exposure limits in the sample of 61 countries with fifth‐generation (5G) technology. Indeed, restrictive RF‐EMF exposure limits are constraining 5G deployment in a context of the widespread adoption of mobile‐broadband technologies. These results should be useful for policymakers and mobile operators alike to anticipate the outcome of legislation in countries that have yet to introduce 5G technology. The results should also be useful when reviewing policies and strategies for the implementation of the upcoming 6G technology in frequency bands that will be increasingly higher (above 6 GHz up to THz for very local usage), and hence where the health effects on humans are less well studied. [ABSTRACT FROM AUTHOR]

Nowadays the efforts of not only companies, but also governments in different countries are aimed at the development of 5G technologies. On the one hand, the introduction of 5G is an expensive process that requires investments in the development, deployment and maintenance of infrastructure, the involvement of a large number of market participants and service providers, the creation of a stimulating and regulatory legislative framework, the provision of radio frequencies of a more efficient spectrum, the solution of patenting issues. On the other hand, the introduction of 5G technologies will be aimed at developing the economy of many industries, creating social benefits, reducing energy intensity, and will create new opportunities for companies. Currently, the benefits of the digital economy can be most used by the United States, the Republic of Korea and China, which have the highest rates of 5G adoption in the world. The countries of the European Union are also interested in the development of 5G technologies. We analysed key 5G technologies for 74,940 related patents for 23 EU countries for the period 2012–2021. It is shown that the leaders in the number of 5G patents were Sweden, Germany, Finland, France, the Netherlands and Ireland. It is noteworthy that countries can either focus on developing a small number of technologies, or develop a wide range of them. Since 2018, France, Estonia and Germany demonstrate the greatest number of technological specializations primarily creating inventions related to 5G data processing. At the same time, the USA, the Republic of Korea and China still retain their competitive advantages in fields of basic electric elements and electric communication technique for fifth generation networks. To improve positions in the global technology market the EU countries need to specialize in rarer and more complex technologies and develop national policies in this area. [ABSTRACT FROM AUTHOR]

Recent progress studies in light of wireless communication systems mainly centred around two focuses: zero-energy consumption and ultra-reliable and low-latency communication (URLLC). Among various cutting-edge areas, exploiting ambient backscatter communication (Backcom) has recently been devised as one of the foremost solutions for achieving zero energy consumption through the viability of ambient radio frequency. Meanwhile, using short-packet communication (SPC) is the cheapest way to reach the goal of URLLCs. Upon these benefits, we investigate the feasibility of Backcom and SPC for symbiotic wireless sensor networks by analyzing the system performance. Specifically, we provide a highly approximated mathematical framework for evaluating the block-error rate (BLER) performance, followed by some useful asymptotic results. These results provide insights into the level of diversity and coding gain, as well as how packet design impacts BLER performance. Numerical results confirm the efficacy of the developed framework and the correctness of key insights gleaned from the asymptotic analyses. [ABSTRACT FROM AUTHOR]

Introduction Methods Results Conclusion Due to its unique features, pulsed field ablation (PFA) could potentially overcome some limitations of current radiofrequency (RF) ventricular tachycardia (VT) ablation. However, data on the use of PFA in this setting are currently scarce.Two patients with ischemic cardiomyopathy and previously failed RF VT ablations were treated with PFA.A total of 18 bipolar applications (case1) and seven bipolar applications (case2) were delivered to the infero‐lateral and infero‐septal areas (case1) and to the apical lateral left ventricular (LV) wall (case2), placing the catheter adjacent to the LV wall in the flower configuration. A rapid cessation of VT and restoration of sinus rhythm were observed during PFA delivery in both cases. Further applications were delivered to achieve complete elimination of late potentials. In case 1, during the in‐hospital stay, ECG monitoring did not show VT recurrences. Six‐month follow‐up was uneventful, with no VT recurrences at ICD interrogation. In case 2, due to postdischarge VT recurrences, a second RF procedure was scheduled 1 month later. The voltage map performed in sinus rhythm showed a low‐voltage zone located at the anterolateral wall, near the previous ablation site. Numerous late potentials were recorded. At the 6‐month follow‐up, no further VT recurrences were documented after RF redo ablation.While the speed of application and potential transmural effect can facilitate the ablation of large diseased endocardial areas, early loss of contact due to difficult pentaspline catheter manipulation in the LV could lead to insufficient contact force and, consequently, inadequate energy penetration. [ABSTRACT FROM AUTHOR]

Practical Application This research aimed to assess the hot air–assisted radio frequency drying (HA‐RFD) of orange slices to evaluate the possibility of producing high‐quality dried orange slices and overcome the problem of the long drying time and the high energy consumption. The effect of electrode distance (60, 70, and 80 mm) and number of slices (1–3 slices; 4 mm thickness per slice) on the HA‐RFD of orange slices was evaluated. Orange slices in three layers with a total thickness of 12 mm and an electrode gap of 70 mm were picked to dry the orange slices in the shortest time. The quality of orange slices dried with HA‐RFD was compared with those of HA‐dried (HAD) and freeze‐dried (FD) samples. HA‐RFD allowed a 67% decrease in the time of drying of the orange slices (from 1170 to 390 min) when compared to HAD. Total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity, and color values were affected by the drying technique. HA‐RFD showed higher TPC, TFC, and antioxidant activity than HAD. The FD samples showed the highest TPC (928 mg GAE/100 g dw), TFC (200 mg rutin/100 g dw), and antioxidant activity (67.58%). Moreover, the samples dried with HA‐RFD resulted in the least color change in comparison to HAD and FD samples. Regarding vitamin C, FD samples were the best, followed by HA‐RFD and HAD, respectively. Considering the final product quality, and the characteristics of drying techniques, especially drying time and drying rate, HA‐RFD proved to be an alternative technique to the HAD for producing dried orange slices.HA‐RFD was applied for the first time as an alternative technology to dry orange slices. The quality of orange samples dried by HA‐RFD was compared with samples that dried by HAD and FD. The results indicated that the HA‐RFD technique is a good method to dry orange slices by considering the drying characteristics and the final product quality. [ABSTRACT FROM AUTHOR]

A feasibility study on cobalt ferrite-barium titanate (CFO-BTO) core-shell nanocomposite as a potential candidate to induce localized hyperthermia is performed through finite element analysis (FEA). The applied field in the radio frequency range (RF) to the simulated nanosized magneto-electric (ME) CFO-BTO core-shell nanocomposites is translated to heat energy due to (i) eddy current loss (ii) hysteresis loss and (iii) relaxation loss. A quantitative estimation of the hysteresis loss and eddy current loss is evaluated. The required temperature for hyperthermia is approximately 315K and the Pennes bioheat equation is used to study the rate of change in the temperature of the surrounding dielectric tissue. The FEA is used to study the temperature gradient as a function of time for four cases: (i) no nanoparticles (ii) using CFO-BTO to generate hyperthermia (iii) using cobalt ferrite (CFO) to generate hyperthermia (iv) increasing the concentration of CFO-BTO to generate hyperthermia. It was evident that the rate of temperature increase is higher for CFO-BTO compared to CFO. This can be attributed to the acoustic translation of energy between the magnetostrictive and piezoelectric shells. The results also indicate that increasing the concentration of CFO-BTO allows a faster rate of applied field energy translation to internal energy due to close interparticle interaction. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions QRS morphology can change during ventricular arrhythmias (VAs) with the appearance of bundle branch block (BBB).We retrospectively investigated 195 consecutive patients who underwent an initial ablation of VA. The study inclusion criteria were VAs that were successfully ablated in the outflow tract (OT) and in whom right bundle branch block (RBBB) was induced by catheter manipulation close to the His bundle area during sinus rhythm, before any radiofrequency application. We analyzed the QRS morphology of the VAs with and without RBBB during sinus beats.Twenty‐four patients (age 59 ± 17 years, female 14) developed RBBB at some point during their procedure. The successful ablation sites of the VAs were the right ventricular outflow tract (RVOT) in 12 patients, pulmonary artery in one, left coronary cusp in five, right coronary cusp in three, right‐left cusp junction in two, and great cardiac vein in two. QRS‐morphology change was observed in five (20%) cases. The successful ablation sites in that group were the left coronary cusp in three cases, right coronary cusp in one, and RVOT septum in one. The QRS duration of the VAs increased during RBBB.There are some cases of OT‐VAs in which the QRS waveform changes with the appearance of catheter induced RBBB. We need to be aware that when QRS morphology changes during an OT‐VA ablation, it does not necessarily mean that the origin or exit of the VA has changed. [ABSTRACT FROM AUTHOR]