Modulation Control Research Articles

Probiotics in Periodontal and Peri-Implant Health Management: Biofilm Control, Dysbiosis Reversal, and Host Modulation.

Periodontitis and peri-implantitis are microbially associated diseases of the tissues supporting the teeth and dental implants that are mediated by host inflammation and eventually lead to tooth and dental implant loss. Given the probiotics' role in biofilm control, dysbiosis reversal, and host modulation, their potential beneficial effects on the improvement of periodontitis and peri-implantitis have been recently investigated. Moreover, probiotics use has also been proposed in periodontal health management in patients undergoing fixed orthodontic therapy. Therefore, the present study aimed to review, considering the periodontal microbiome composition around teeth and dental implants in healthy and pathological conditions, the putative favorable effects of probiotics on gingivitis, periodontitis, and peri-implantitis. The secondary aim of the present narrative review was to synthesize the supporting evidence and proposed protocols for probiotics use as adjuncts in periodontitis and peri-implantitis treatment and the periodontal health management of orthodontic patients with fixed appliances. Contrasting findings from the literature may be due to the different methods, posology, and duration of probiotics prescriptions and due to the heterogeneous biological and clinical measurement methods employed. Thus, no definitive conclusions could be drawn about the effectiveness of probiotics in periodontal management, both in healthy and pathological conditions. Further studies are needed to validate probiotics for periodontal management and provide recommended protocols.

Single-Stage Isolated and Bidirectional Three-Phase Series-Resonant AC–DC Converter: Modulation for Active and Reactive Power Control

Single-stage isolated and bidirectional (SSIB) AC–DC converters have a high potential for future solid-state transformers and smart battery chargers due to their reduced volume and high efficiency. However, there is a research gap for SSIB reactive power injection. This article introduces an SSIB three-phase AC–DC converter composed of three low frequency rectifiers linked by tiny film capacitors with a quad-active-bridge series-resonant (QABSR) DC–DC. A novel QAB modulation is proposed to solve three issues: (1) Three DC inputs with high ripple compensation, (2) active–reactive power injection, and (3) minimization of high-frequency (HF) transformers currents. The rectified grid voltages were modulated by time-variant duty ratio (DR) angles. In contrast, the DC source was modulated by a fixed DR (FDR) angle along with a phase-shift angle which changes according to the grid current amplitude. A constant HF current amplitude with minimum value was obtained. It is shown that the HF current amplitude is increased for reactive power injection. Hence, the FDR angle was used to compensate for this increase. Active and reactive power control were validated in a 2 kW prototype. Compared with other structures, tiny DC-link capacitors and smaller L filters were used. Moreover, higher efficiency (96%) and smaller grid currents THDi (3%) were obtained.

Band-type resonance: non-discrete energetically optimal resonant states

Structural resonance involves the absorption of inertial loads by a tuned structural elasticity: a process playing a key role in a wide range of biological and technological systems, including many biological and bio-inspired locomotion systems. Conventional linear and nonlinear resonant states typically exist at specific discrete frequencies and specific symmetric waveforms. This discreteness can be an obstacle to resonant control modulation: deviating from these states, by modulating waveform asymmetry or drive frequency, generally leads to losses in system efficiency. Here, we demonstrate a new strategy for achieving these modulations at no loss of energetic efficiency. Leveraging fundamental advances in nonlinear dynamics, we characterise a new form of structural resonance: band-type resonance, describing a continuous band of energetically optimal resonant states existing around conventional discrete resonant states. These states are a counterexample to the common supposition that deviation from a linear (or nonlinear) resonant frequency necessarily involves a loss of efficiency. We demonstrate how band-type resonant states can be generated via a spectral shaping approach: with small modifications to the system kinematic and load waveforms, we construct sets of frequency- and asymmetry-modulated resonant states that show equal energetic optimality to their conventional discrete analogues. The existence of these non-discrete resonant states in a huge range of oscillators—linear and nonlinear, in many different physical contexts—is a new dynamical systems phenomenon. It has implications not only for biological and bio-inspired locomotion systems but for a constellation of forced oscillator systems across physics, engineering, and biology.

Molecular Plasmonics with Metamaterials.

Molecular plasmonics, the area which deals with the interactions between surface plasmons and molecules, has received enormous interest in fundamental research and found numerous technological applications. Plasmonic metamaterials, which offer rich opportunities to control the light intensity, field polarization, and local density of electromagnetic states on subwavelength scales, provide a versatile platform to enhance and tune light-molecule interactions. A variety of applications, including spontaneous emission enhancement, optical modulation, optical sensing, and photoactuated nanochemistry, have been reported by exploiting molecular interactions with plasmonic metamaterials. In this paper, we provide a comprehensive overview of the developments of molecular plasmonics with metamaterials. After a brief introduction to the optical properties of plasmonic metamaterials and relevant fabrication approaches, we discuss light-molecule interactions in plasmonic metamaterials in both weak and strong coupling regimes. We then highlight the exploitation of molecules in metamaterials for applications ranging from emission control and optical modulation to optical sensing. The role of hot carriers generated in metamaterials for nanochemistry is also discussed. Perspectives on the future development of molecular plasmonics with metamaterials conclude the review. The use of molecules in combination with designer metamaterials provides a rich playground both to actively control metamaterials using molecular interactions and, in turn, to use metamaterials to control molecular processes.

Current Sensor Fault-Tolerant Control for Five-Phase PMSM Drives Based on Third-Harmonic Space

According to the different forms of back electromotive force, five-phase permanent-magnet synchronous motors (FPMSMs) can be divided into two types: sinusoidal FPMSMs (SFPMSMs) and trapezoidal FPMSMs (TFPMSMs). In field-oriented-controlled FPMSM drives, current sensors may malfunction in harsh working environments. In this article, two current sensor fault-tolerant control (FTC) strategies based on third-harmonic space, respectively, corresponding to SFPMSMs and TFPMSMs are proposed. Different from three-phase motor, the decoupled model of five-phase motor contains two orthogonal subspaces. The key to both strategies is that the third-harmonic space currents are controlled at zero when current sensors malfunction. Thus, the faulty phase current can be estimated with other phase currents by using the constraint equations of current transformation. For SFPMSMs, vector control and sinusoidal pulsewidth modulation technology are used to control the third-harmonic space currents to zero. For TFPMSMs, offset axis transformation and resonant observer are adopted for third-harmonic space current estimation and the third-harmonic space currents are controlled to zero by using the estimated values as feedback of vector control. The experimental results demonstrate that the robustness of both current sensor FTC systems is well performed in the whole speed range.

Synchronous Multi-Zone Modulation for Control of Inverter-Based Power Electronic Systems: Overview of Recent Research

This publication provides a brief overview of the results of recent research works by the author in the field of power electronics, carried out and published mainly in 2019–2021, and awarded with the Premium “Boris Lazarenko” of the Academy of Sciences of Moldova in the field of engineering. The methodological basis of those investigations is an original alternative method of the synchronous multi-zone space-vector modulation of signals of voltage source inverters as the main workhorses of adjustable speed electric drives and renewable energy systems. Therefore, basic strategies, schemes, and algorithms of synchronous multi-zone modulation have been further developed, modernized, modified, and disseminated for the control of novel promising topologies of power conversion systems for variable speed drives and for photovoltaic installations. It is shown that the developed schemes and algorithms of the synchronous space-vector modulation applied for control of inverter-based systems provide continuous synchronization and symmetry of the basic voltage waveforms of systems during the whole control range. It provides minimization of even harmonics and undesirable subharmonics (of the fundamental frequency) in spectra of the basic voltages of systems, leading to reducing the losses in the systems and to increasing their efficiency. Based on a comparative analysis of the integral spectral characteristics of the phase voltage of the systems, recommendations are formulated for the rational choice of schemes and algorithms of the synchronous space-vector modulation for the relevant installations, depending on the modes of their operation.

Phenolic Compounds Present in Yerba Mate Potentially Increase Human Health: A Critical Review.

Yerba Mate (YM) is a food product derived from Ilex paraguariensis whose constituents obtained from its extract, mainly the phenolic fraction, have been linked to numerous health benefits, such as cardiovascular protection, weight reduction, glucose control, and gene modulation. However, evidences linking phenolic compounds (PC) intake and human health are still limited and often contentious. Several researches have shown that key PC elements are poorly absorbed in humans and exist predominantly as conjugates, which may not be bioactive but may play a crucial role when interacting with the gut microbiota (GM). As the intestine is the largest microorganism-populated organ in the human body, GM has been regarded as a “microbial organ”, acting as a second genome for modulating the host’s health phenotype. For this reason, the study of intestinal microbiota has received considerable attention in recent years. Its impact on the development of nutrition-related diseases must motivate broader researches on the interaction between YM’s PC and GM regarding the production of metabolites that may influence human health. This review aimed to gather and assess the available information about how PC from YM may impact host metabolism and the immune system and GM.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11130-022-01008-8.

锂硫电池非均相电催化剂

<p indent="0mm">With the rapid development of electronic transportation and portable electronics, commercial lithium-ion batteries would be unsatisfactory to meet the needs of future markets owing to the relatively low energy density. Seeking a reliable substitution system is becoming imperative. Lithium-sulfur (Li-S) battery has been recognized as a cutting-edge energy storage system because of its high theoretical capacity (1672 mAh g^–1) and cost-effectiveness of sulfur resources. Nevertheless, the severe shuttle effect and sluggish reaction kinetics significantly restrict its further commercialization. In the developing history of Li-S batteries, physical confinement and chemical adsorption have often been employed to achieve the anchoring of polysulfides. However, these strategies are still difficult to fully solve the problems of slow reaction kinetics and poor cycle performance. Recent years have witnessed the introduction of heterogeneous electrocatalysts into the Li-S system, which readily meets with great success in suppressing the shuttle effect and elevating the reaction kinetics. In this review, we introduce the basic reaction of Li-S battery and point out the main challenges in its current development stage, followed by summarizing the effects of electrocatalysts. Firstly, the polar electrocatalyst is able to effectively adsorb polysulfide and inhibit its diffusion in the electrolyte. Secondly, the electrocatalyst can effectively promote the conversion of polysulfide and improve the utilization rate of sulfur species. Thirdly, the uniform distribution of active sites in the electrocatalyst also contributes to the uniform deposition of short-chain polysulfides. In addition, the concepts and comparisons of homogeneous and heterogeneous electrocatalysts are presented, manifesting the essential significance of heterogeneous electrocatalysts in Li-S system. Homogeneous electrocatalysts usually refer to small soluble organic molecules with the same phase state as soluble polysulfides in the reaction system. Homogeneous electrocatalysts have more specific catalytic sites, whilst heterogeneous electrocatalysts have more diverse morphologies and higher possibility of multi-site synergistic catalysis. Then the common regulation strategies for heterogeneous electrocatalysts are classified, including vacancy regulation, doping regulation, heterostructure modulation, size control, and phase modulation. In further contexts, the underlying mechanisms of different regulation strategies for promoting polysulfide conversion are discussed. The introduction of heterogeneous electrocatalysts can effectively promote the reaction kinetics and improve their electrochemical performance. However, there are still many obstacles waiting to be solved in the practicability of Li-S batteries. For instance, there is a lack of highly selective and stable electrocatalysts. The identification of real catalytic sites in the electrocatalysts still remains unclear. Moreover, Li-S batteries have poor performance under lean electrolyte and low lithium consumption. In view of these issues, future development strategy is put forward from four aspects, encompassing material exploration, precise synthesis, characterization methods and practical application, aiming to bridge the gap between the reality and ideal in working Li-S batteries.

Extending Combinatorial Regulatory Network Modeling to Include Activity Control and Decay Modulation

Understanding how the structure of within-system interactions affects the dynamics of the system is important in many areas of science. We extend a network dynamics modeling platform DSGRN, which combinatorializes both dynamics and parameter space to construct finite but accurate summaries of network dynamics, to new types of interactions. While the standard DSGRN assumes that each network edge controls the rate of abundance of the target node, the new edges may control either activity level or a decay rate of its target. While motivated by processes of post-transcriptional modification and ubiquitination in systems biology, our extension is applicable to the dynamics of any signed directed network.

Analysis and Simulation of Overmodulation Modes of a Three-Inverter Block of the Photovoltaic Installation

The purpose of this work is to modernize the control scheme of a transformer-based photovoltaic system with three inverters controlled by the modified algorithms of synchronous spacevector PWM in order to ensure linear regulation of the system in the overmodulation zone of the inverter block in the process of forming a symmetrical and synchronized (with the operating frequency of the system) voltage on the inverter-side windings of a power transformer. This goal is achieved by the fact that the process of two-stage control of the system in the zone of overmodulation of inverters is carried out on the basis of synchronized phase shifts between the control signals of inverters (a constant phase shift, as well as an additional adjustable phase shift between the inverter signals as a function of the duration of clock subintervals), with an appropriate modification of the algorithms of synchronous PWM of inverters due to the inclusion of two specialized correction factors in the basic functional dependencies. The most significant results of the work include the fact that in a system with a modified control scheme and modulation of the inverter block in the overmodulation zone, the resulting voltage on the inverter-side windings of the power transformer is characterized by quarterwave symmetry, and its spectrum contains no even-order harmonics, as well as subharmonics, including regimes of fluctuations in the operating frequency of the system connected to a three-phase network, thereby helping to reduce losses in the transformer windings and improve the efficiency of photovoltaic systems.

Improved Switching Ripple Modulation Strategy for Simultaneous Power Conversion and Data Communication in DC–DC Converters

Switching ripple communication (SRC), which modulates the PWM carrier with digital data and takes the switching ripple as a signal carrier, helps power electronic converters to transfer digital data along with power. This article discusses the theory and implementation of SRC technology. It proves that the modulation using square wave and sinusoidal wave carriers is compatible. The fundamental principles of frequency hopping–differential phase shift keying (FH–DPSK) modulation are then analyzed in detail, and an improved FH–DPSK scheme is proposed to suppress output voltage disturbances, thereby maintaining power quality, reducing communication noise, and separating power control and data modulation. Furthermore, to evaluate the reliability of the communication technique, the effect of power conversion on communication is discussed in detail. Finally, a buck converter with a switching frequency of 100/83.3 kHz is set up, and the experiment achieves a 16.7 kbps bit rate using quaternary modulation, demonstrating the correctness of the scheme.

A triple boost 13‐level switched‐capacitor based multi‐level inverter topology for solar PV applications

AbstractA High Gain High‐Level switched‐capacitor multilevel inverter with low voltage stress requires a lower number of devices at peak output voltage and a reduced number of circuit components along with an increase in voltage boosting capability. The features of the proposed topology include inherent boosting (Gain: 3) and self‐voltage balancing properties. To avoid complex algorithms, calculations and obtain superior quality output voltage the nearest level control (NLC) modulation technique is used. The extension of the topology has also been derived for the higher voltage gain and levels by adding four switches and one capacitor. The proposed topology has been compared with the recently developed topologies. The power loss analysis and simulation analysis has been done with different loading conditions under the environment of PLECS 4.2.18 and MATLAB® 2018a, respectively. A hardware bench has been set up to show the verification of the simulation results with hardware results.

Role of Transposable Elements in Genome Stability: Implications for Health and Disease.

Most living organisms have in their genome a sizable proportion of DNA sequences capable of mobilization; these sequences are commonly referred to as transposons, transposable elements (TEs), or jumping genes. Although long thought to have no biological significance, advances in DNA sequencing and analytical technologies have enabled precise characterization of TEs and confirmed their ubiquitous presence across all forms of life. These findings have ignited intense debates over their biological significance. The available evidence now supports the notion that TEs exert major influence over many biological aspects of organismal life. Transposable elements contribute significantly to the evolution of the genome by giving rise to genetic variations in both active and passive modes. Due to their intrinsic nature of mobility within the genome, TEs primarily cause gene disruption and large-scale genomic alterations including inversions, deletions, and duplications. Besides genomic instability, growing evidence also points to many physiologically important functions of TEs, such as gene regulation through cis-acting control elements and modulation of the transcriptome through epigenetic control. In this review, we discuss the latest evidence demonstrating the impact of TEs on genome stability and the underling mechanisms, including those developed to mitigate the deleterious impact of TEs on genomic stability and human health. We have also highlighted the potential therapeutic application of TEs.

Passively phase-locked Er:fiber source of single-cycle pulses in the near infrared with electro-optic timing modulation for field-resolved electron control.

A single-cycle light source in the near infrared is demonstrated enabling sensitive applications of ultrafast optical field control of electronic transport. The compact Er:fiber system generates passively phase-locked pulses with broadband spectra covering 150 THz to 350 THz at a duration of 4.2 fs and 40 MHz repetition rate. A second output arm is equipped with an electro-optic modulator (EOM) that switches the arrival time of the pulses by 700 ps at arbitrary frequencies up to 20 MHz, enabling timing modulation of the pump pulse without changing the average intensity. As a benchmark demonstration, we investigate the carrier relaxation dynamics in low-temperature-grown InGaAs (LT-InGaAs) using quantum interference currents (QuICs).

Simultaneous enhancement of quantum cutting luminescence in Er-doped NaBaPO4 phosphors by crystal field control and plasmonic modulation

It is of great significance to enhance the quantum-cutting (QC) luminescence for practical applications due to the narrow absorption cross-section and low luminescence efficiency of rare earth ions. In this work, NaBaPO4:Er3+ phosphors doped with Li+ were synthesized through a solid-state reaction. The QC luminescence of NaBaPO4:Er3+ phosphor was enhanced 5.71 times by doping Li+. XRD patterns and Judd-Ofelt calculations demonstrated the crystal field distortion when introduced Li+, which would increase the transition probability of Er3+. Furthermore, NaBaPO4:Er3+, Li+ phosphors were decorated with silver nanoparticles (Ag NPs). The effect of Ag NPs on QC luminescence was studied, and the results showed that QC luminescence was further enhanced up to 1.95 times by Ag NPs. FDTD simulations revealed that Ag NPs generated substantial surface plasmons, which would boost the excitation rate of Er3+. Our studies would provide a useful strategy to enhance QC luminescence, which has potential application in germanium-based solar cells.

On the Development and Experimental Validation of a Novel and Intuitive Interior Permanent Magnet Synchronous Motor Controller for Electric Vehicle Application

This paper discusses the process of developing a novel and robust algorithm for an interior permanent magnet synchronous motor controller. This is necessary for the simplification of the setting of control parameters and maintaining the proper operation of the motor. A 3D torque lookup table was used in which two inputs were considered, i.e., accelerator movements and the motor rotational speed. These two inputs allowed the lookup table to generate a specified torque at any motor rotation, which was then fed-forward to the field-oriented control and space vector pulse width modulation algorithm. Modeling, simulation, and experimental tests were performed to design and validate the proposed controller. The experimental validation shows that the proposed controller worked as intended. This was indicated by its ability to control the motor to obtain a 7% higher torque output than in the simulation in the constant torque region. In the field-weakening region, the controller could make the motor reach a maximum speed of 5500 RPM. There was only an 8% difference compared to the simulation (6500 RPM). In terms of maximum power generated, the controller was able to match the simulation output with only a 5% difference.

Comparison of Proportional and PWM Pneumatic Control in Terms of Positioning and Compressed Air Consumption

In this paper is shown a comparison of proportional pneumatic control and Pulse Width Modulation (PWM) pneumatic control in terms of positioning and compressed air consumption. All experimental tests were performed on a device for lifting and holding of the workpieces, which consists of one vertically mounted rodless cylinder with integrated vacuum gripper. In the case of the proportional pneumatic control, cylinder piston is always positioning in the correct position, but position losses are recurring during the time (in majority of cases, the position loss is 4 mm). As the control system constantly returns the cylinder piston to the desired position, that increases the compressed air consumption. In the case of the PWM pneumatic control, the position error is occurring (in majority of cases, the absolute value of the relative position error is less than 2%), but there is no position loss during the period of workpiece holding, i.e. there is no additional compressed air consumption. The compressed air consumption differential is approximately 18.6%. In addition, in case of Meter-out control in combination with previously defined types of control, the positioning is more accurate but the compressed air consumption slightly increases with decreasing the opening level of the one-way flow control valve.

Vibration Characteristics of the Dual Electric Propulsion System of Vessels under Electromechanical Coupling Excitation

An electromechanical coupling driving system is a commonly used system for large overloading ships. In this paper, a dual input electromechanical coupling model, including an inverter power supply, three-phase induction motor, fixed-axis gear, and load, is established. The influences of the gear error, inverter, and coupling stiffness on the vibration characteristics of the system are studied, and the influences of each parameter on the vibration characteristics are analyzed. The inverter power supply part considers the constant voltage–frequency ratio control and sinusoidal pulse width modulation, as well as the inverter. The motor part uses the dynamic motor model based on the equivalent circuit. The fixed-axis gear section uses a translation–torsion model with time-varying mesh stiffness and damping. The mechanical part and the motor part are coupled with the load torque of the motor. The results show that the greater the error of the gear, the greater the vibration of the system, and the rotation frequency error is the main factor. Secondly, by comparing the influence of error value and accuracy difference on vibration, we found that when an accuracy difference exists, the dominant factor of system vibration is the accuracy difference. Thirdly, the use of an inverter also increases the vibration of the electromechanical coupling system. Finally, we found that the lower stiffness of the elastic coupling reduced the vibration of the system.

Utilization of Mind-Body Intervention for Integrative Health Care of COVID-19 Patients and Survivors.

Recent findings suggest a correlation between COVID-19 and diabetes, although the underlying causes are still little understood. COVID-19 infection tends to induce severe symptoms in patients with underlying diabetes, increasing their mortality rate. Moreover, COVID-19 itself appears to be a diabetogenic factor. In addition, mental health conditions, such as depression due to lockdown and anxiety about infection, were found to affect glycemic control and immunity, highlighting the importance of mental health care during the pandemic. Mind–Body Intervention (MBI), which includes meditation, yoga, and qigong, has emerged as a tool for mental health management due to its effects on stress reduction and the promotion of mental and physical well-being. Here, we review the latest randomized controlled trials to determine the effects of MBI on glycemic control and the immune system and discuss the underlying mechanisms by which MBI facilitates the virtuous cycle of stress management, glycemic control, and immune modulation. Furthermore, we examine the actual utilization of MBI during the COVID-19 pandemic era through recent studies. With proper online education, non-pharmacological MBI may be more widely used as an important tool for self-health care that complements the usual treatment of COVID-19 patients and survivors.

Magnetic Anisotropy Control with Curie Temperature above 400 K in a van der Waals Ferromagnet for Spintronic Device.

The technological appeal of van der Waals ferromagnetic materials is the ability to control magnetism under external fields with desired thickness toward novel spintronic applications. For practically useful devices, ferromagnetism above room temperature or tunable magnetic anisotropy is highly demanded but remains challenging. To date, only a few layered materials exhibit unambiguous ferromagnetic ordering at room temperature via gating techniques or interface engineering. Here, it is demonstrated that the magnetic anisotropy control and dramatic modulation of Curie temperature (Tc ) up to 400 K are realized in layered Fe5 GeTe2 via the high-pressure diamond-anvil-cell technique. Magnetic phases manifesting with in-plane anisotropic, out-of-plane anisotropic and nearly isotropic magnetic states can be tuned in a controllable way, depicted by the phase diagram with a maximum Tc up to 360 K. Remarkably, the Tc can be gradually enhanced to above 400 K owing to the Fermi surface evolution during a pressure loading-deloading process. Such an observation sheds light on the understanding and control of emergent magnetic states in practical spintronic applications.