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Prachi Patel,1 Maja Green,2 Jennifer Tram,3 Eugene Wang,4 Melissa Murphy,5 Alaa a Abd-Elsayed,6 Krishnan Chakravarthy2 1Houston Methodist Willowbrook Hospital, Neuroscience Centre, Houston, Tx, USA; 2NXTSTIM INC. Department of Pain Medicine, San Diego, CA, USA; 3UCLA David Geffen School of Medicine/VA, Los Angeles, CA, 90095, USA; 4Timothy Growth, Pain Management and Chiropractic Care, Smithtown, NY, USA; 5North Texas Orthopedics and Spine Center, Grapevine, TX, 76051, USA; 6University of Wisconsin School of Medicine and Public Health, Health Sciences Learning Center, Madison, WI, 53705, USACorrespondence: Maja Green, Chief Scientific Officer, NXTSTIM Inc., Department of Pain Medicine, 5362 Sweetwater Trails, San Diego, CA, 92130, USA, Email mgreen@nxtstim.comAbstract: Transcutaneous Electrical Nerve Stimulation (TENS) and Electronic Muscle Stimulation (EMS) are non-invasive therapies widely used for pain relief and neuromuscular adaptation. However, the clinical research supporting the efficacy of TENS in chronic pain management is limited by significant methodological flaws, including small sample sizes and inconsistent reporting of stimulation parameters. TENS modulates pain perception through various techniques, targeting specific nerve fibers and pain pathways. High-frequency TENS is effective for segmental pain control, while low-frequency TENS, reliant on endogenous opioid pathways, may be less effective in opioid-tolerant patients. Additionally, TENS may influence autonomic functions, such as micro-perfusion and sympathetic tone, further broadening its therapeutic potential. EMS, on the other hand, enhances muscle strength and neuromuscular function, particularly in rehabilitation settings, by recruiting additional muscle fibers and improving neuromuscular efficiency. To address the limitations in existing clinical applications, future advancements in TENS and EMS technologies should focus on real-time optimization of stimulation parameters, consistent therapy delivery, and improved accessibility. Integrating automated and personalized adjustments can help streamline treatment, enhance patient compliance, and overcome traditional barriers to the effective implementation of these modalities. Additionally, developing systems that enable remote monitoring and customization of therapy protocols will expand the usability of TENS and EMS in diverse care settings. Future research must focus on rigorous study designs, standardized protocols, and meaningful patient-centered outcomes to fully realize the therapeutic potential of these modalities. Innovations like NXTSTIM EcoAI™ represent a significant advancement in delivering tailored, effective, and patient-friendly pain management and rehabilitation strategies.Keywords: chronic pain, TENS, EMS, neurotransmitters, gate control theory, central sensitization

Background and Objectives Gate control theory and fear-avoidance model of chronic pain posit that biopsychosocial factors can modulate pain. Nonpharmacological interventions are recommended in managing chronic pain, but little information is available regarding their efficacy in older adults. We examined and compared the efficacy of different nonpharmacological intervention approaches for chronic pain management among older adults via meta-analysis and subgroup analysis. Research Design and Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO number CRD42020222767), a systematic search was undertaken using MEDLINE, Embase, and PsycINFO up to March 21, 2022. Randomized controlled trials were included, and data were pooled using a random-effects meta-analysis model. Risk of bias was assessed using a quality rating scale for psychological interventions. Results Twenty-five trials (N = 2,394 participants) were identified. Six types of nonpharmacological interventions were compared with control conditions (sham/attention control and treatment as usual). Nonpharmacological interventions were associated with significant reductions in pain intensity, pain interference, depressive symptoms, catastrophizing beliefs, and improvement in physical performance (standardized mean differences −0.34 to 0.54). Subgroup analyses based on different nonpharmacological approaches revealed the benefits of psychological approaches combined with physical activity. Discussion and Implications Nonpharmacological interventions, particularly those adopting psychological approaches and physical activity, have a small but statistically significant effect on chronic pain management in older adults. Reduction in pain interference may be related to reduced catastrophizing beliefs, thus providing support for the fear-avoidance model. Further research with adequate power is needed to establish the efficacy and mechanism of various intervention modalities for older adults. [ABSTRACT FROM AUTHOR]

Dry needlings primary goal is to alleviate pain by inserting solid filament needles into muscles, tendons, and ligaments to provide a stimulus that inhibits nerve endings to decrease pain. This critically appraised topic investigates the effects dry needling has on patients with various chronic pain conditions and its ability to relieve pain. Articles were selected if patients had a chronic pain condition lasting at least 3 months, pain was reported using the Visual Analog Scale, and were randomized control trials or prospective studies. All selected studies for this critically appraised topic showed significant improvement in chronic pain. With these improvements, dry needling has been shown to be an effective treatment in chronic pain conditions. [ABSTRACT FROM AUTHOR]

Pain is one of the most common symptoms. Clinically, pain can be a symptom of many clinical diseases, or it can occur as a disease alone. At the same time, pain can be used as a warning of injury to the body, causing a series of defensive protective reactions. For the mechanism of pain, researchers in different periods have carried out studies from nerve, body fluid and other aspects. Some hypotheses have been proposed, such as the gate control theory of pain, endogenous pain suppression system and other concepts. With the clinical trial research more deeply, the discussion on the mechanism of pain is becoming more and more diversified and systematic. Acupuncture is a unique treatment of diseases originating in China. It is a therapeutic method to treat diseases in the body through the conduction of channels and acupoints, and the application of certain manipulative methods. Broadly speaking, acupuncture therapy includes acupuncture and moxibustion two major aspects. At the same time, acupuncture and moxibustion are also the important methods for the clinical treatment of pain, especially acupuncture treatment. Acupuncture analgesia has a long history. According to traditional Chinese medicine (TCM), it is regarded that “Causes of pain were mainly in two aspects as obstruction and malnourishment. Obstruction of the channels and collaterals could lead to pain. Failure of nourishing in viscera and bowels could also lead to pain”. Acupuncture therapy has the therapeutic effect of dredging the channels and unblocking the collaterals, harmonizing yin and yang, as well as reinforcing healthy qi and dispelling pathogenic qi. Thus, it has a certain therapeutic effect on different types of pain. Under the continuous in-depth study of modern medicine, the mechanism and principle of acupuncture analgesia have gradually penetrated from the aspect of ancient channels, collaterals and acupoints to the molecular level of nerve cells and neurotransmitters, electrophysiology and so on. The mechanism of acupuncture analgesia is one of the most active fields in medical research. This paper summarizes and discusses the local mechanism of acupuncture participating in pain control from the six aspects, as gate control theory, conduction and regulation of adenosine, inflammatory response, ion channel in acupoint area, mast cell in acupoint area, and connective tissue. [ABSTRACT FROM AUTHOR]

Researchers have been studying the pain sensation extensively in the past few decades. Quantitative simulation and theoretical modeling of pain sensation based on experimental results are necessary for pain research. Many theories have been proposed to explain the mechanism of pain from molecular, cellular, and neuron network perspectives. But some phenomena in pain sensation are not fully understood, including wind-up and ramp-off. This paper focused on the theoretical model of wind-up and ramp-off phenomena in the pain sensation. With the addition of the transduction model, the generation mechanism of wind-up and ramp-off is better explained. The simulations were carried out to analyze the skin pain sensation under the mechanical stimulus, consisting of four different parts: the mechanical model of skin, transduction, transmission, modulation, and perception. The stress distribution on the skin was obtained based on the elastic theory. And the modified Hodgkin and Huxley model and the mathematical model of gate control theory were utilized to analyze the process of transduction, modulation, and perception, respectively. The numerical experiments demonstrated the wind-up occurs with a frequent stimulus of 1 Hz and 2 Hz, and ramp-off appears with the withdrawal of constant mechanical stimulus, which could contribute to the understanding of the pain sensation mechanism. [ABSTRACT FROM AUTHOR]

Skin pain resulting from mechanical compression is one of the most common pains in daily life and the indispensable information for electronic skin to perceive external signals. The external mechanical stimuli are transduced into impulses and transmitted via nerve fiber, and finally, the sensation is perceived via the procession of the nerve system. However, the mathematical mechanism for pain sensation due to mechanical stimuli remains unclear. In this paper, a mathematical model for skin pain sensation under compression is established, in which the Flament solution, the revised Hodgkin–Huxley model, and the mathematical model gate control theory are considered simultaneously. The proposed model includes three parts: a mechanical model of skin compression, a model of transduction, and a model of modulation and perception. It is demonstrated that the pain sensation degree increases with the compression amplitude and decreases with deeper nociceptor location in the skin. With the help of the proposed model, the quantitative relationship between compression pain sensation and external mechanical stimuli is revealed, which has a significant benefit in promoting the design and mechanism research of electronic skin with pain perception function. [ABSTRACT FROM AUTHOR]

The sensory inflow from the periphery that triggers innocuous and painful sensations is highly complex, capturing key elements of the nature of any stimulus, its location, intensity, and duration, and converting this to dynamic action potential firing across a wide population of afferents. While sensory afferents are highly specialized to detect these features, their input to the spinal cord also triggers active processing and modulation there which determines its output, to drive the sensory percept experienced and behavioral responses. Focus on such active spinal modulation was arguably first introduced by Melzack and Wall in their Spinal Cord Gate Control theory. This theory has had a profound influence on our understanding of pain, and especially its processing, as well as leading directly to the development of clinical interventions, and its historical importance certainly needs to be fully recognized. However, the enormous progress we are making in the understanding of the function of the somatosensory system, means that it is time to incorporate these newly discovered features into a more complex and accurate model of spinal sensory modulation.

Background and Aim: To evaluate and compare the efficacy of external cold and a vibrating device in reducing the pain and anxiety amidst children receiving maxillary infiltration anaesthesia over conventional methods. Method: A sum of thirty subjects aged between 5 and 10 years who had undergone dental procedures requiring maxillary infiltration were enrolled in the current split-mouth randomised control study. The control intervention constitutes infiltration of 1.8 mL of 2% lignocaine in addition to 1:100,000 adrenaline (Lox, Neon Laboratories Mumbai, India) whereas, the experimental group used external cold and a vibrating device (Buzzy®, MMJ Labs, Atlanta, GA, USA) in annexation to the control protocol. Simultaneous to LA administration, pulse rate was employed as an objective measure and the subjective measure was recorded using RMS Pictorial Scale (RMS-PS) for the child's discomfort. To document the child's pain as anticipated by the dentist the revised face, limbs, arms, cry and consolability (FLACC-R) scale was employed. Result: Lower pain sensation and anxiety was recorded in the experimental group using Buzzy when compared to control. Conclusion: External cold in adjacent with vibrations might be efficient in lowering pain as well as anxiety in children experiencing infiltration dental anaesthesia though further research work is requisite with a larger sample size.

The superficial dorsal horn (SDH) of the spinal cord represents the first site of integration between innocuous and noxious somatosensory stimuli. According to gate control theory, diverse populations of excitatory and inhibitory interneurons within the SDH are activated by distinct sensory afferents, and their interplay determines the net nociceptive output projecting to higher pain centers. Although specific SDH cell types are ill defined, numerous classifications schemes find that excitatory and inhibitory neurons fundamentally differ in their morphology, electrophysiology, neuropeptides, and pain-associated plasticity; yet little is known about how these neurons respond over a range of natural innocuous and noxious stimuli. To address this question, we applied an in vivo imaging approach in male mice where the genetically encoded calcium indicator GCaMP6s was expressed either in vGluT2-positive excitatory or vIAAT-positive inhibitory neurons. We found that inhibitory neurons were markedly more sensitive to innocuous touch than excitatory neurons but still responded dynamically over a wide range of noxious mechanical stimuli. Inhibitory neurons were also less sensitive to thermal stimuli than their excitatory counterparts. In a capsaicin model of acute pain sensitization, the responses of excitatory neurons were significantly potentiated to innocuous and noxious mechanical stimuli, whereas inhibitory neural responses were only depressed to noxious stimuli. These in vivo findings show that excitatory and inhibitory SDH neurons diverge considerably in their somatosensory responses and plasticity, as postulated by gate control theory. [ABSTRACT FROM AUTHOR]

Neurostimulation therapies are frequently used in patients with chronic pain conditions. They emerged from Gate Control Theory (GCT), which posits that Aβ-fiber activation recruits superficial dorsal horn (SDH) inhibitory networks to "close the gate" on nociceptive transmission, resulting in pain relief. However, the efficacy of current therapies is limited, and the underlying circuits remain poorly understood. For example, it remains unknown whether ongoing stimulation of Aβ-fibers is sufficient to drive activity in SDH neurons. We used multiphoton microscopy in spinal cords extracted from mice expressing the genetically encoded calcium indicator GCaMP6s in glutamatergic and GABAergic populations; activity levels were inferred from deconvolved calcium signals using CaImAn software. Sustained Aβ-fiber stimulation at the dorsal columns or dorsal roots drove robust yet transient activation of both SDH populations. Following the initial increase, activity levels decreased below baseline in glutamatergic neurons and were depressed after stimulation ceased in both populations. Surprisingly, only about half of GABAergic neurons responded to Aβ-fiber stimulation. This subset showed elevated activity for the entire duration of stimulation, while non-responders decreased with time. Our findings suggest that Aβ-fiber stimulation initially recruits both excitatory and inhibitory populations but has divergent effects on their activity, providing a foundation for understanding the analgesic effects of neurostimulation devices. Perspective: This article used microscopy to characterize the responses of mouse spinal cord cells to stimulation of non-painful nerve fibers. These findings deepen our understanding of how the spinal cord processes information and provide a foundation for improving pain-relieving therapies. [ABSTRACT FROM AUTHOR]

Background and Aim: To evaluate and compare the efficacy of external cold and a vibrating device in reducing the pain and anxiety amidst children receiving maxillary infiltration anaesthesia over conventional methods. Method: A sum of thirty subjects aged between 5 and 10 years who had undergone dental procedures requiring maxillary infiltration were enrolled in the current split-mouth randomised control study. The control intervention constitutes infiltration of 1.8 mL of 2% lignocaine in addition to 1:100,000 adrenaline (Lox, Neon Laboratories Mumbai, India) whereas, the experimental group used external cold and a vibrating device (Buzzy®, MMJ Labs, Atlanta, GA, USA) in annexation to the control protocol. Simultaneous to LA administration, pulse rate was employed as an objective measure and the subjective measure was recorded using RMS Pictorial Scale (RMS-PS) for the child's discomfort. To document the child's pain as anticipated by the dentist the revised face, limbs, arms, cry and consolability (FLACC-R) scale was employed. Result: Lower pain sensation and anxiety was recorded in the experimental group using Buzzy when compared to control. Conclusion: External cold in adjacent with vibrations might be efficient in lowering pain as well as anxiety in children experiencing infiltration dental anaesthesia though further research work is requisite with a larger sample size. [ABSTRACT FROM AUTHOR]

Skin pain resulting from mechanical compression is one of the most common pains in daily life and the indispensable information for electronic skin to perceive external signals. The external mechanical stimuli are transduced into impulses and transmitted via nerve fiber, and finally, the sensation is perceived via the procession of the nerve system. However, the mathematical mechanism for pain sensation due to mechanical stimuli remains unclear. In this paper, a mathematical model for skin pain sensation under compression is established, in which the Flament solution, the revised Hodgkin–Huxley model, and the mathematical model gate control theory are considered simultaneously. The proposed model includes three parts: a mechanical model of skin compression, a model of transduction, and a model of modulation and perception. It is demonstrated that the pain sensation degree increases with the compression amplitude and decreases with deeper nociceptor location in the skin. With the help of the proposed model, the quantitative relationship between compression pain sensation and external mechanical stimuli is revealed, which has a significant benefit in promoting the design and mechanism research of electronic skin with pain perception function.

Implantable peripheral nerve stimulation (PNS) currently plays a significant role as a 4th step analgesic treatment in chronic refractory pain. This technique was first developed in the 1960s but it was not until the end of the 20th Century when it grew exponentially with the development of the percutaneous implantation technique. Based on the "Gate Control Theory" described by Dr Melzack and Dr Wall, PNS modulates the nociceptive information transmitted to the medullary posterior horn. Percutaneous implantation of an electrode at the peripheral level using ultrasound imaging or fluoroscopy is simple and minimally invasive. The transmission of electrical signals is performed either through a pulse generator located in a remote reservoir or transdermally by an external transmitter. The prior assessment of patients by a multidisciplinary team is essential to include or exclude those patients who are candidates for therapy. Current scientific evidence offers promising results for the use of this technique in patients with neuropathic refractory pain when compared to other treatments. The following article reviews the action mechanism of peripheral nerve stimulation, the percutaneous implantation technique, as well as the indications in relation to a clinical case in a patient with secondary neuropathic pain to Complex Regional Pain Syndrome (CRPS). [ABSTRACT FROM AUTHOR]

Highlights • Wind-up of spinal cord is an important phenomenon in central sensitization. • We propose a more realistic network model for wind-up. • Short-term synaptic plasticity is used for regulating the weights of our model. • This model might be helpful in developing a therapeutic method for chronic pain. Abstract The treatment of chronic pain depends mainly on our understanding of the mechanisms such as central sensitization which is involved in it. Wind-up of spinal cord is one of the most important phenomena in the study of central sensitization which has received considerable attention in recent years. Wind-up is a form of short-term synaptic plasticity (STP) that can lead to central sensitivity. Although several models have been proposed for wind-up, none of them are based on the experimental evidence. In this study, a new network model is introduced according to the gate control theory of pain. Neuroids are used as neuron models in which their parameters are captured from available experimental data. Adjusting the weights of the network is based on the short-term synaptic plasticity. The results of the time and frequency domain show that the model can well simulate wind-up behavior. This model can be used for analyzing, predicting and controlling chronic pain in the future. [ABSTRACT FROM AUTHOR]

The Gate Control Theory of pain, published more than half a century ago to explain nociceptive modulation of peripheral sensory input, assumes inhibition of incoming nociceptive (pain) information produced by mechanical stimulation. To verify the presence of such a gate control mechanism at the level of the human trigeminal system, we evaluated the effects on pain sensation of a proprioceptive trigeminal stimulation induced by mandibular extension. We found that such a stimulation, applied for 7 min, was effective in increasing both the threshold and tolerance of tooth pain induced by electrical activation of dental nociceptors. Moreover the antinociceptive effect lasted for several minutes after the proprioceptive stimulus had ceased. We also tested whether an exteroceptive palatal stimulation superimposed on the proprioceptive stimulation would increase the effects on tooth pain perception of human volunteers. We observed that the exteroceptive stimulation significantly increased the antinociceptive effect induced by the sole proprioceptive stimulation. The physiological mechanisms and the possible implications of these observations are discussed.

The gate control theory of pain postulates that the sensation of pain can be reduced or blocked by closing a "gate" at the earliest synaptic level in the spinal cord, where nociceptive (pain) afferents excite the ascending interneurons that transmit the signal to the brain. Furthermore, the gate can be induced to close by stimulating touch afferents with receptive fields in the same general area as the trauma that is generating the pain (the "rub it to make it better" effect). A considerable volume of research has substantiated the theory and shown that a key mechanism mediating the gate is pre-synaptic inhibition, and that this inhibition is generated by depolarizing IPSPs in the nociceptor central terminals (primary afferent depolarization; PAD). Both pre-synaptic inhibition and depolarizing IPSPs are topics that students often regard as matters of secondary importance (if they are aware of them at all), and yet they are crucial to a matter of primary importance to us all - pain control. This report describes some simple computer simulations that illustrate pre-synaptic inhibition and explore the importance of the depolarizing aspect of the IPSPs. These concepts are then built into a model of the gate control of pain itself. Finally, the simulations show how a small change in chloride homeostasis can generate the dorsal root reflex, in which nociceptor afferents generate antidromic spikes which may increase neurogenic inflammation and actually exacerbate pain. The hope is that the simulations will increase awareness and understanding of a topic that is important in both basic neuroscience and medical neurology., (Copyright © 2023 Faculty for Undergraduate Neuroscience.)

Spinal cord stimulation (SCS) is a minimally invasive therapy used for the treatment of chronic neuropathic pain. SCS is a safe and effective alternative to medications such as opioids, and multiple randomized controlled studies have demonstrated efficacy for difficult‐to‐treat neuropathic conditions such as failed back surgery syndrome. Conventional SCS is believed mediate pain relief via activation of dorsal column Aβ fibers, resulting in variable effects on sensory and pain thresholds, and measurable alterations in higher order cortical processing. Although potentiation of inhibition, as suggested by Wall and Melzack's gate control theory, continues to be the leading explanatory model, other segmental and supraspinal mechanisms have been described. Novel, non‐standard, stimulation waveforms such as high‐frequency and burst have been shown in some studies to be clinically superior to conventional SCS, however their mechanisms of action remain to be determined. Additional studies are needed, both mechanistic and clinical, to better understand optimal stimulation strategies for different neuropathic conditions, improve patient selection and optimize efficacy. [ABSTRACT FROM AUTHOR]

This paper demonstrates a high-performance black phosphorus nanoribbons field-effect transistor (BPNR-FET) and systematically investigates methods for enhancing its anisotropic carrier transport. The BPNR-FET shows a strong dependence on crystal orientation in which the best mobility performance is achieved in armchair-oriented nanoribbons. A downscaling of nanoribbon width is shown to improve the short-channel effect owing to a better electrostatic gate control. Furthermore, hydrogenation is employed to effectively passivate the dangling bonds and heal the nanoribbon edge defects, leading to nearly hysteresis-free transfer properties. By virtue of bandgap and contact-metal workfunction engineering, n-type BPNR-FET is successfully demonstrated, which enables complementary inverter circuits to be simultaneously realized. This paper unravels the superior performance underscores a conceptually new BPNR-FET, paving the way toward the development of non-planar devices and integrated circuits based on 2-D materials platform. [ABSTRACT FROM AUTHOR]

The Gate Control Theory of pain, published more than half a century ago to explain nociceptive modulation of peripheral sensory input, assumes inhibition of incoming nociceptive (pain) information produced by mechanical stimulation. To verify the presence of such a gate control mechanism at the level of the human trigeminal system, we evaluated the effects on pain sensation of a proprioceptive trigeminal stimulation induced by mandibular extension. We found that such a stimulation, applied for 7 min, was effective in increasing both the threshold and tolerance of tooth pain induced by electrical activation of dental nociceptors. Moreover the antinociceptive effect lasted for several minutes after the proprioceptive stimulus had ceased. We also tested whether an exteroceptive palatal stimulation superimposed on the proprioceptive stimulation would increase the effects on tooth pain perception of human volunteers. We observed that the exteroceptive stimulation significantly increased the antinociceptive effect induced by the sole proprioceptive stimulation. The physiological mechanisms and the possible implications of these observations are discussed. [ABSTRACT FROM AUTHOR]

The Central Governor Model (CGM) ignited a paradigm shift from concepts of catastrophic failure towards central regulation of exercise performance. However, the CGM has focused on the central integration of afferent feedback in homeostatic control. Accordingly, it neglected the important role of volitional self-regulatory control and the integration of affective components inherently attached to all physiological cues. Another limitation is the large reliance on the Gestalt phenomenon of perceived exertion. Thus, progress towards a comprehensive multidimensional model of perceived fatigability and exercise regulation is needed. Drawing on Gate Control Theory of pain, we propose a three-dimensional framework of centrally regulated and goal-directed exercise behaviour, which differentiates between sensory, affective and cognitive processes shaping the perceptual milieu during exercise. We propose that: (A) perceived mental strain and perceived physical strain are primary determinants of pacing behaviour reflecting sensory-discriminatory processes necessary to align planned behaviour with current physiological state, (B) core affect plays a primary and mediatory role in exercise and performance regulation, and its underlying two dimensions hedonicity and arousal reflect affective-motivational processes triggering approach and avoidance behaviour, and (C) the mindset-shift associated with an action crisis plays a primary role in volitional self-regulatory control reflecting cognitive-evaluative processes between further goal-pursuit and goal-disengagement. The proposed framework has the potential to enrich theory development in centrally regulated and goal-directed exercise behaviour by emphasising the multidimensional dynamic processes underpinning perceived fatigability and provides a practical outline for investigating the complex interplay between the psychophysiological determinants of pacing and performance during prolonged endurance exercise. [ABSTRACT FROM AUTHOR]

In this paper we will implement a transcutaneous electrical nerve stimulation (TENS) designed for medical applications in order to reduce acute and chronic pains. This procedure uses electrical currents pulses applied on the skin area via electrodes. Two kinds of stimulation are adopted: the peripheral nerve stimulation (PNS) and the spinal cord stimulation (SCS). In either, a small pulse generator sends electrical pulses to the nerves (in PNS stimulation) or to the spinal cord (SCS stimulation). Previous studies on TENS technique showed that the obtained results are not very satisfactory and depend on the patient’s state, condition, age, and stimulation parameters. In order to optimize the conditions and parameters stimulation during treatments, we present in this paper a new strategy called pulse width modulation stimulation (PWM-TENS) based on a parametric computing of frequency, current intensity, pulse duration of stimuli. To implement our approach, we used an embedded platform under Arduino-Uno with five several programs depending on the pain category and according to international medical standards and specifications. The first tests on 15 volunteer patients showed satisfaction ratio (EVA) after 5-12 days and a pain reduction between 80 and 20 after 1 month of stimulation. This result is important because it prolongs the analgesic effect and reduces therapeutic rehabilitation period. The medical aspect of the subject is to have a medical tool that allows objective evaluations for short and medium periods of pain treatments with dynamic evaluation metrics. [ABSTRACT FROM AUTHOR]

Aim: Pain is highly subjective and it is neurologically proven that stimulation of larger diameter fibers - e.g., using appropriate coldness, warmth, rubbing, pressure or vibration - can close the neural "gate" so that the central perception of itch and pain is reduced. This fact is based upon "gate control" theory of Melzack and Wall. The present study was carried out to investigate the effects of vibration stimuli on pain experienced during local anesthetic injections. Materials and Methods: Thirty patients aged 6-12 years old of both the genders with Frankel′s behavior rating scale as positive and definitely positive requiring bilateral local anesthesia injections for dental treatment were included in the split-mouth cross over design. Universal pain assessment tool was used to assess the pain with and without vibration during the administration of local anesthesia and the results obtained were tabulated and statistically analyzed. Results: Local anesthetic administration with vibration resulted in significantly less pain (P = 0.001) compared to the injections without the use of vibe. Conclusion: The results suggest that vibration can be used as an effective method to decrease pain during dental local anesthetic administration.

A parking management system needs to be designed to improve the efficiency of the management of parking lots in urban business districts that witness difficult parking. In this paper, the overall design of an intelligent parking system is expounded, the architecture of which includes the PXA270 master control platform, ZigBee network, the remote communication section and Android software; the LCD interface circuit is stated and the design philosophy for the analogue camera circuit is described. Meanwhile, the functions of the parking-space detection module and the vehicle identification unit are explained, and the structure diagram of the software in the intelligent parking system is put forward. Also, the design philosophies for the gate control unit and the GPRS communication program are expounded, a detailed definition of the control frame of the gate module is given, the flow charts of the parking-space status detection procedure and the vehicle identification procedure are presented, and the server of the Android system and the software design for the client are described. Furthermore, the flow chart of the network communication thread is put forward, in which data is transferred between the server and the client, the interface design for the intelligent parking system is realized, the display of the system’s main interface is presented, and the parking-space reservation interface and the function of entry guiding animation are realized. [ABSTRACT FROM AUTHOR]

In the setting of injury, myelinated primary afferent fibers that normally signal light touch are thought to switch modality and instead signal pain. In the absence of injury, touch is perceived as more intense when firing rates of A-afferents increase. However, it is not known if varying the firing rates of Aβ afferents have any consequence to the perception of dynamic mechanical allodynia (DMA). We hypothesized that, in the setting of injury, the unpleasantness of DMA would be intensified as the firing rates of Aβ afferents increase. Using a stimulus-response protocol established in normal skin, where an increase in brush velocity results in an increase of Aβ afferent firing rates, we tested if brush velocity modulated the unpleasantness of capsaicin-induced DMA. We analyzed how changes in estimated low-threshold mechanoreceptor firing activity influenced perception and brain activity (functional MRI) of DMA. Brushing on normal skin was perceived as pleasant, but brushing on sensitized skin produced both painful and pleasant sensations. Surprisingly, there was an inverse relationship between Aβ firing rates and unpleasantness such that brush stimuli that produced low firing rates were most painful and those that elicited high firing rates were rated as pleasant. Concurrently to this, we found increased cortical activity in response to low Aβ firing rates in regions previously implicated in pain processing during brushing of sensitized skin, but not normal skin. We suggest that Aβ signals do not merely switch modality to signal pain during injury. Instead, they exert a high- and low-frequency-dependent dual role in the injured state, with respectively both pleasant and unpleasant consequences. [ABSTRACT FROM AUTHOR]

The article discusses the assessment and management of complex pain in children. Topics include impact on pain on children's sleep, mood, school attendance, and social function; assessing the changes in sensory and motor function associated with the pain; and risk of developing persistent pain after surgery in children and adults.

This paper presents a novel compact circuit combining function of gate control and voltage balancing for series-connected silicon carbide (SiC) metal–oxide–semiconductor field-effect transistor (MOSFET). Two series-connected SiC MOSFETs with the proposed circuit only require a single standard gate driver to achieve the gate control and voltage balancing during both steady-state and switching transition. Moreover, the proposed circuit is only composed of ten passive components. Therefore, the proposed circuit provides a low-cost and highly reliable method to increase the blocking voltage of the SiC MOSFET. The operation principles of the proposed circuit are theoretically analyzed. In addition, the high-blocking-voltage device is not only required in switching-mode power supply (SMPS) but also in dc-breaker applications. The proposed circuit is then modified to make it suitable to the dc-breaker applications. The simulation and experimental results validate the effectiveness and superiority of the proposed circuit in both SMPS and dc-breaker applications. [ABSTRACT FROM PUBLISHER]

Background: New psychoactive substances (NPS) continue to emerge; however, few surveys of substance use ask about NPS use. Research is needed to determine how to most effectively query use of NPS and other uncommon drugs. Objective: To determine whether prevalence of self-reported lifetime and past-year use differs depending on whether or not queries about NPS use are preceded by “gate questions.” Gate questions utilize skip-logic, such that only a “yes” response to the use of specific drug class is followed by more extensive queries of drug use in that drug class. Methods: We surveyed 1,048 nightclub and dance festival attendees (42.6% female) entering randomly selected venues in New York City in 2016. Participants were randomized to gate vs. no gate question before each drug category. Analyses focus on eight categories classifying 145 compounds: NBOMe, 2C, DOx, “bath salts” (synthetic cathinones), other stimulants, tryptamines, dissociatives, and non-phenethylamine psychedelics. Participants, however, were asked about specific “bath salts” regardless of their response to the gate question to test reliability. We examined whether prevalence of use of each category differed by gate condition and whether gate effects were moderated by participant demographics. Results: Prevalence of use of DOx, other stimulants, and non-phenethylamine psychedelics was higher without a gate question. Gate effects for other stimulants and non-phenethylamine psychedelics were larger among white participants and those attending parties less frequently. Almost one in ten (9.3%) participants reporting no “bath salt” use via the gate question later reported use of a “bath salt” such as mephedrone, methedrone, or methylone. Conclusion: Omitting gate questions may improve accuracy of data collected via self-report. [ABSTRACT FROM PUBLISHER]