Neuromodulatory Research Articles

Design of a high-power harmonic waveguide filter for radar transmitter

In this article, we present the research results on the designing and manufacturing method of a high-power harmonic filter applied in the X-band transmitter system. The harmonic filter utilizes Waffle-iron filters and quarter-wavelength converters on the waveguide. As a result, the loss and ripple within the passband are improved, while meeting the requirements of cutting off high-order harmonics. Based on the application of microwave theory and simulation software tools, the research team have calculated, designed and manufactured a harmonic filter that meets all the requested specifications for application in X-band transmitter systems: Loss ≤ 0,12dB@8,9-9,6GHz; Reflection coefficient ≤ -20dB@8,9-9,6GHz; Frequency selectivity ≤ -40dB@2nd harmonic, 3rd harmonic, 4th harmonic.

Contribution of hypothalamic orexin (hypocretin) circuits to pathologies of motivation.

The orexin (also known as hypocretin) system, consisting of neuropeptides orexin-A and orexin-B, was discovered over 25 years ago and was immediately identified as a central regulator of sleep and wakefulness. These peptides interact with two G-protein coupled receptors, orexin 1 (OX1) and orexin 2 (OX2) receptors which are capable of coupling to all heterotrimeric G-protein subfamilies, but primarily transduce increases in calcium signalling. Orexin neurons are regulated by a variety of transmitter systems and environmental stimuli that signal reward availability, including food and drug related cues. Orexin neurons are also activated by anticipation, stress, cues predicting motivationally relevant information, including those predicting drugs of abuse, and engage neuromodulatory systems, including dopamine neurons of the ventral tegmental area (VTA) to respond to these signals. As such, orexin neurons have been characterized as motivational activators that coordinate a range of functions, including feeding and arousal, that allow the individual to respond to motivationally relevant information, critical for survival. This review focuses on the role of orexins in appetitive motivation and highlights a role for these neuropeptides in pathologies characterized by inappropriately high levels of motivated arousal (overeating, anxiety and substance use disorders) versus those in which motivation is impaired (depression).

Lifting With Neuromodulators.

The use of botulinum toxins for facial rejuvenation and improvement of dynamic wrinkles has become a mainstay in the aesthetic treatment armamentarium. However, using these same neuromodulators (NMs) for lifting the structures of the face, is a newer addition to antiaging protocols. The muscles of facial animation all interplay with each other. Lifting can be accomplished by treating those muscles that are responsible for depression, leaving the elevators unopposed and resulting in a rejuvenated, lifted outcome. Brow lifting, cheek lifting, and even contouring of the lower face and jawline are all possibilities using NMs. To review the literature and current practices in techniques for lifting the different anatomic facial zones. The authors present and discuss the published data and personal experiences of using NM for lifting and retraining of the facial musculature. This article will discuss the effects and approaches to lifting with botulinum toxin injections, including the potential success and side effects associated with these off-label injections. The use of botulinum toxins has expanded beyond its traditional use as a reducer of dynamic wrinkles. A significant amount of published data now exists for the off-label use of botulinum toxins for lifting and shaping the face. These can be considered advanced techniques as each region has its own anatomic intricacies and side effects can occur. More placebo-controlled objective data would also help elucidate exact dosing strategies for each region.

Dangerous Intersection of Alcoholism and Othello Syndrome: A Comprehensive Review of Delusional Jealousy and Treatment Strategies.

The modern pace of life, increased susceptibility to stressors, and easy access to psychoactive substances have contributed to the increase in the number of people addicted to alcohol. Alcoholism has serious and life-threatening consequences, one of which is brain damage causing morbid jealousy, otherwise known as Othello syndrome. The disease, currently classified as a subtype of delusional disorder, manifests itself in groundless and dangerous judgments about a partner's sexual infidelity. People with Othello syndrome constantly believe in their partner's infidelity despite inadequate evidence of it. Patients become aggressive toward their partners as well as themselves, which is why in a fit of anger they can commit murder or suicide. Othello syndrome can occur as a symptom of an underlying mental illness, but it is most often associated with brain damage caused by chronic alcohol use. Antipsychotic drugs and serotonin reuptake inhibitors are used in pharmacotherapy. Targeted treatment using the neuropeptide oxytocin, which modulates the transmitter systems responsible for disease symptoms, is also being considered. The use of oxytocin seems groundbreaking, but it remains at the research stage. The treatment of addictions and primary diseases, as well as long-term cognitive-analytic psychotherapy, also have a huge impact. Othello syndrome is a life-threatening disease with an insidious course and serious consequences. This article aims to review the manifestations of morbid jealousy, including delusional disorder, and the association with alcoholism.

Narrow-Band, Band-Stop Filter Designs with Different Numbers of L-Resonators

Filters have an important place in RF and microwave engineering. Filtering certain frequencies is one of the most basic needs in receiver and transmitter systems. Today, microstrip filters are used in many areas of microwave engineering such as radar systems, cellular communications, test/measurement systems, wireless modems, radio and television receivers, and remote control systems. In these filter structures; high performance, low loss, small size, and low-cost requirements are sought. In this study, narrow-band, band-stop filter designs with different numbers of L-resonators at a frequency of 2.45 Hz were realized. The main goal of this study is to design filters with higher performance, lower return loss, and more compact and useful sizes. Thanks to these filter designs, undesirable signals are filtered and targeted signals are transmitted appropriately.

D2-like dopamine receptors blockade within the dentate gyrus shows a greater effect on stress-induced analgesia in the tail-flick test compared to D1-like dopamine receptors.

Acute stress, as a protective mechanism to respond to an aversive stimulus, can often be accompanied by suppressing pain perception via promoting consistent burst firing of dopamine neurons. Besides, sensitive and advanced research techniques led to the recognition of the mesohippocampal dopaminergic terminals, particularly in the hippocampal dentate gyrus (DG). Moreover, previous studies have shown that dopamine receptors within the hippocampal DG play a critical role in induced antinociceptive responses by forced swim stress (FSS) in the presence of inflammatory pain. Since different pain states can trigger various mechanisms and transmitter systems, the present experiments aimed to investigate whether dopaminergic receptors within the DG have the same role in the presence of acute thermal pain. Ninety-seven adult male albino Wistar rats underwent stereotaxic surgery, and a stainless steel guide cannula was unilaterally implanted 1 mm above the DG. Different doses of SCH23390 or sulpiride as D1- and D2-like dopamine receptor antagonists were microinjected into the DG 5-10 min before exposure to FSS, and 5 min after FSS exposure, the tail-flick test evaluated the effect of stress on the nociceptive response at the time-set intervals. The results demonstrated that exposure to FSS could significantly increase the acute pain perception threshold, while intra-DG administration of SCH23390 and sulpiride reduced the antinociceptive effect of FSS in the tail-flick test. Additionally, it seems the D2-like dopamine receptor within the DG plays a more prominent role in FSS-induced analgesia in the acute pain model.

Future Directions for Developing Non-dopaminergic Strategies for the Treatment of Parkinson's Disease.

The symptomatic treatment of Parkinson's disease (PD) has been dominated by the use of dopaminergic medication, but significant unmet need remains, much of which is related to non-motor symptoms and the involvement of non-dopaminergic transmitter systems. As such, little has changed in the past decades that has led to milestone advances in therapy and significantly improved treatment paradigms and patient outcomes, particularly in relation to symptoms unresponsive to levodopa. This review has looked at how pharmacological approaches to treatment are likely to develop in the near and distant future and will focus on two areas: 1) novel non-dopaminergic pharmacological strategies to control motor symptoms; and 2) novel non-dopaminergic approaches for the treatment of non-motor symptoms. The overall objective of this review is to use a 'crystal ball' approach to the future of drug discovery in PD and move away from the more traditional dopamine-based treatments. Here, we discuss promising non-dopaminergic and 'dirty drugs' that have the potential to become new key players in the field of Parkinson's disease treatment.

A fixed‐frequency second‐order generalized integrator phase‐locked loop‐based phase synchronization control in multisegment wireless power transfer systems

SummaryMultisegment wireless power transfer (MSWPT) technology provides a solution to the challenges of dust‐free environments and automation faced by automated material handling systems (AMHS) in current semiconductor wafer factories. However, variations in track current frequency and phase offset on the transmitting side of the MSWPT technology may lead to significant deficits in energy transmission capability. This paper introduces a method based on the fixed‐frequency second‐order generalized integrator phase‐locked loop (FFSOGI‐PLL) structure for frequency and phase synchronization among multiple transmitters in a MSWPT system. By synchronizing the track currents of multiple transmitters, this method significantly enhances the energy harvesting capacity of the H‐type pickup in the overhead hoist transport (OHT) system, ensuring stable voltage at the receiver (Rx) load. Both theoretical simulations and experiments confirm that the proposed method can effectively capture the phase difference of track current and achieve frequency locking and phase tracking. Building on this theoretical foundation, we constructed three transmitter (Tx) systems and a 1.5 kW Rx equipped with an H‐type pickup. This setup is capable of real‐time monitoring and phase‐synchronization control of track currents with varying phase offsets. The results convincingly demonstrate the strong performance and stability of the proposed method.

Interactions of catecholamines and GABA+ in cognitive control: Insights from EEG and 1H-MRS

Catecholamines and amino acid transmitter systems are known to interact, the exact links and their impact on cognitive control functions have however remained unclear. Using a multi-modal imaging approach combining EEG and proton-magnetic resonance spectroscopy (1H-MRS), we investigated the effect of different degrees of pharmacological catecholaminergic enhancement onto theta band activity (TBA) as a measure of interference control during response inhibition and execution. It was central to our study to evaluate the predictive impact of in-vivo baseline GABA+ concentrations in the striatum, the anterior cingulate cortex (ACC) and the supplemental motor area (SMA) of healthy adults under varying degrees of methylphenidate (MPH) stimulation. We provide evidence for a predictive interrelation of baseline GABA+ concentrations in cognitive control relevant brain areas onto task-induced TBA during response control stimulated with MPH. Baseline GABA+ concentrations in the ACC, the striatum, and the SMA had a differential impact on predicting interference control-related TBA in response execution trials. GABA+ concentrations in the ACC appeared to be specifically important for TBA modulations when the cognitive effort needed for interference control was high – that is when no prior task experience exists, or in the absence of catecholaminergic enhancement with MPH. The study highlights the predictive role of baseline GABA+ concentrations in key brain areas influencing cognitive control and responsiveness to catecholaminergic enhancement, particularly in high-effort scenarios.

Local age-dependent neuromodulation in Rhodnius prolixus antennae.

Kissing bugs do not respond to host cues when recently molted and only exhibit robust host-seeking several days after ecdysis. Behavioral plasticity has peripheral correlates in antennal gene expression changes through the week after ecdysis. The mechanisms regulating these peripheral changes are still unknown, but neuropeptide, G-protein coupled receptor, nuclear receptor, and takeout genes likely modulate peripheral sensory physiology. We evaluated their expression in antennal transcriptomes along the first week postecdysis of Rhodnius prolixus 5th instar larvae. Besides, we performed clustering and co-expression analyses to reveal relationships between neuromodulatory (NM) and sensory genes. Significant changes in transcript abundance were detected for 50 NM genes. We identified 73 sensory-related and NM genes that were assigned to nine clusters. According to their expression patterns, clusters were classified into four groups: two including genes up or downregulated immediately after ecdysis; and two with genes with expression altered at day 2. Several NM genes together with sensory genes belong to the first group, suggesting functional interactions. Co-expression network analysis revealed a set of genes that seem to connect with sensory system maturation. Significant expression changes in NM components were described in the antennae of R. prolixus after ecdysis, suggesting that a local NM system acts on antennal physiology. These changes may modify the sensitivity of kissing bugs to host cues during this maturation interval.

Optical proximity sensors using multiple quantum well didoes

InGaN/GaN multiple quantum well (MQW) diodes perform multiple functions, such as optical emission, modulation and reception. In particular, the partially overlapping spectral region between the electroluminescence (EL) and responsivity spectra of each diode results in each diode being able to sense light from another diode of the same MQW structure. Here, we present a noncontact, optical proximity sensing system by integrating an MQW-based light transmitter and detector into a tiny GaN-on-sapphire chip. Changes in the external environment modulate the light emitted from the transmitter. Reflected light is received by the on-chip MQW detector, wherein the carried external modulation information is converted into electrical signals that can be extracted. The maximum detection proximity is approximately 17 mm, and the displacement detection accuracy is within 1 mm. Based on the detection of distance, we extend the application of the sensor to vibration and pressure detection. This monolithic integration design can replace external discrete light transmitter and detector systems to miniaturize reflective sensor architectures, enabling the development of novel optical sensors.

Predicting the coupling of HPEM waveform with a power amplifier in perforated conductive enclosure using FDDM/VF

AbstractOne of the most common methods to protect electronic and telecommunication systems in a high‐power electromagnetic (HPEM) environment is using a conductive enclosure. Amplifiers are the vital parts in transmitter and receiver systems as the main components of a telecommunication system, so investigating the effects of HPEM waveform on their performance is very important. The Presence of apertures in the body of the conductive enclosure, as well as non‐linear elements such as transistors in amplifiers, adds to the complexity of examining the coupling of electromagnetic fields on the performance of amplifiers. Considering the importance of the topic, in this study, the impact of the HPEM waveform on the power amplifier inside the conductive enclosure has been investigated. By using the finite difference delay modelling (FDDM) numerical method as a stable method followed by the vector fitting (VF) method, the electromagnetic problem has become a circuit problem, which allows examining the response of the power amplifier and any circuit, including non‐linear elements against the interference field. Responses of bipolar linear and non‐linear components in the perforated conductive enclosure by the proposed method have been compared with the results obtained by computer simulation technology microwave studio (CST‐MWS) for verification.

Auditory brainstem responses are resistant to pharmacological modulation in Sprague Dawley wild-type and Neurexin1α knockout rats

Sensory processing in the auditory brainstem can be studied with auditory brainstem responses (ABRs) across species. There is, however, a limited understanding of ABRs as tools to assess the effect of pharmacological interventions. Therefore, we set out to understand how pharmacological agents that target key transmitter systems of the auditory brainstem circuitry affect ABRs in rats. Given previous studies, demonstrating that Nrxn1α KO Sprague Dawley rats show substantial auditory processing deficits and altered sensitivity to GABAergic modulators, we used both Nrxn1α KO and wild-type littermates in our study. First, we probed how different commonly used anesthetics (isoflurane, ketamine/xylazine, medetomidine) affect ABRs. In the next step, we assessed the effects of different pharmacological compounds (diazepam, gaboxadol, retigabine, nicotine, baclofen, and bitopertin) either under isoflurane or medetomidine anesthesia. We found that under our experimental conditions, ABRs are largely unaffected by diverse pharmacological modulation. Significant modulation was observed with (i) nicotine, affecting the late ABRs components at 90 dB stimulus intensity under isoflurane anesthesia in both genotypes and (ii) retigabine, showing a slight decrease in late ABRs deflections at 80 dB stimulus intensity, mainly in isoflurane anesthetized Nrxn1α KO rats. Our study suggests that ABRs in anesthetized rats are resistant to a wide range of pharmacological modulators, which has important implications for the applicability of ABRs to study auditory brainstem physiology.

A portable frequency‐domain electromagnetic detection system

SummaryFrequency‐domain detection stands as a critical method in remote geophysical exploration; however, its practical application is constrained by the considerable size of the requisite instrumentation. In this paper, we present a compact frequency domain electromagnetic detection system. The integration of intelligent power devices and a novel hardware architecture substantially diminishes the system's dimensions, thereby enhancing its portability. Furthermore, the system design incorporates sinusoidal pulse width modulation and digital phase‐locked amplification to ensure the efficacy of the proposed system. Both the transmitter and receiver system are constrained to dimensions smaller than 1.5 m. Subsequent experimental validation attests to the exemplary hardware performance of the proposed system, with the transmitting voltage of the transmitter circuit attaining 500 V, and the receiver circuit exhibiting a sensitivity as low as 10−8 V. Significantly, this design paradigm not only facilitates the integration of transmitter and receiver systems for frequency‐domain electromagnetic detection but also introduces novel prospects for the application of frequency‐domain electromagnetic detection methods across diverse fields.

The Healthy and Diseased Retina Seen through Neuron-Glia Interactions.

The retina is the sensory tissue responsible for the first stages of visual processing, with a conserved anatomy and functional architecture among vertebrates. To date, retinal eye diseases, such as diabetic retinopathy, age-related macular degeneration, retinitis pigmentosa, glaucoma, and others, affect nearly 170 million people worldwide, resulting in vision loss and blindness. To tackle retinal disorders, the developing retina has been explored as a versatile model to study intercellular signaling, as it presents a broad neurochemical repertoire that has been approached in the last decades in terms of signaling and diseases. Retina, dissociated and arranged as typical cultures, as mixed or neuron- and glia-enriched, and/or organized as neurospheres and/or as organoids, are valuable to understand both neuronal and glial compartments, which have contributed to revealing roles and mechanisms between transmitter systems as well as antioxidants, trophic factors, and extracellular matrix proteins. Overall, contributions in understanding neurogenesis, tissue development, differentiation, connectivity, plasticity, and cell death are widely described. A complete access to the genome of several vertebrates, as well as the recent transcriptome at the single cell level at different stages of development, also anticipates future advances in providing cues to target blinding diseases or retinal dysfunctions.

An integrated packaging hybrid power supply modulator for transmitter systems

An integrated packaging hybrid power supply modulator for transmitter systems

Effects of fisetin on ethanol-induced rewarding properties in mice

ABSTRACT Background: Alcohol use disorder (AUD) is a chronic relapsing disorder associated with compulsive drinking of alcohol. Natural flavonoid fisetin affects a variety of transmitter systems relevant to AUD, such as aminobutyric acid, N-methyl-D-aspartate, and dopamine, as well as peroxisome proliferator-activated receptors. Objectives: This study investigated fisetin’s impact on the motivational properties of ethanol using conditioned place preference (CPP) in mice (n = 50). Methods: Mice were conditioned with ethanol (2 g/kg, i.p.) or saline on alternating days for 8 consecutive days and were given intragastric (i.g.) fisetin (10, 20, or 30 mg/kg, i.g.), 45 min before ethanol conditioning. During extinction, physiological saline was injected to the control and ethanol groups, and fisetin was administered to the fisetin groups. To evaluate the effect of fisetin on the reinstatement of ethanol-induced CPP, fisetin was given 45 min before a priming dose of ethanol (0.4 g/kg, i.p.; reinstatement test day). Results: Fisetin decreased the acquisition of ethanol-induced CPP (30 mg/kg, p < .05) and accelerated extinction (20 and 30 mg/kg, p < .05). Furthermore, fisetin attenuated reinstatement of ethanol-induced CPP (30 mg/kg, p < .05). Conclusions: Fisetin appears to diminish the rewarding properties of ethanol, as indicated by its inhibitory effect and facilitation of extinction in ethanol-induced CPP. These findings imply a potential therapeutic application of fisetin in preventing ethanol-seeking behavior, promoting extinction, and reducing the risk of relapse.

Towards the imaging of deep land ore deposits with ERT-IP method – first results from a demonstration survey in Finland

In this study, we conducted a comprehensive geophysical survey near Kuusamo (Finland) to assess the potential of electrical resistivity methods in delineating mineral deposits at depths greater than 1 km. Preliminary investigations, including magnetic and gravity methods as well as drilling, revealed significant anomalous structures in the survey area. We employed multiple electrical and electromagnetic methods at the site, comprising controlled-source electromagnetic (CSEM), magnetotelluric (MT), electrical resistivity tomography (ERT), and induced polarization (IP). To obtain the geophysical data in very large-scale area, we used a total of 25 transmitter dipoles with 1km long using three distinct transmitter systems and recorded data at 119 receiver stations. In this paper, we present the acquisition and preliminary results from ERT-IP. Analysis of the resistivity and IP responses revealed notable IP signals at depths exceeding 1.5 km. Meanwhile, the resistivity data indicated generally very high values, around 10,000 ohm-m, with complex variations observed near the surface.

Similarity and difference in large-scale functional network alternations between behavioral addictions and substance use disorder: a comparative meta-analysis.

Behavioral addiction (BA) and substance use disorder (SUD) share similarities and differences in clinical symptoms, cognitive functions, and behavioral attributes. However, little is known about whether and how functional networks in the human brain manifest commonalities and differences between BA and SUD. Voxel-wise meta-analyses of resting-state functional connectivity (rs-FC) were conducted in BA and SUD separately, followed by quantitative conjunction analyses to identify the common and distinct alterations across both the BA and SUD groups. A total of 92 datasets with 2444 addicted patients and 2712 healthy controls (HCs) were eligible for the meta-analysis. Our findings demonstrated that BA and SUD exhibited common alterations in rs-FC between frontoparietal network (FPN) and other high-level neurocognitive networks (i.e. default mode network (DMN), affective network (AN), and salience network (SN)) as well as hyperconnectivity between SN seeds and the Rolandic operculum in SSN. In addition, compared with BA, SUD exhibited several distinct within- and between-network rs-FC alterations mainly involved in the DMN and FPN. Further, altered within- and between-network rs-FC showed significant association with clinical characteristics such as the severity of addiction in BA and duration of substance usage in SUD. The common rs-FC alterations in BA and SUD exhibited the relationship with consistent aberrant behaviors in both addiction groups, such as impaired inhibition control and salience attribution. By contrast, the distinct rs-FC alterations might suggest specific substance effects on the brain neural transmitter systems in SUD.

Comparative Effects of Extracts from Leaves of Horseradish Tree Species (Moringa oleifera and Moringa stenopetala) on Memory Index, Monoamine Oxidase activity and Tyrosine Hydroxylase mRNA Expression in Paraquat‐induced Model of Parkinson s disease in Fruit Flies (Drosophila melanogaster)

AbstractBackgroundPD is now understood to be a multi‐system brain condition affecting multiple non‐dopaminergic transmitter systems that grow more prominent as the disease develops. Recent epidemiological and experimental studies have connected pesticides, particularly paraquat, to Parkinson’s disease. Even though the horseradish tree (Moringa oleifera) is a very promising ethnobotanical plant with a wealth of medicinal applications, little is known about the bioactive qualities of alkaloid extracts from its leaves.MethodThis study investigated the comparative modulatory effects of alkaloid extracts of Moringa leaves on the survival rate of paraquat‐induced flies, as well as specific biochemical and genetic markers related to Parkinson’s disease in the heads of the fliesResultThe results showed that the alkaloid extract increased fly survivability (p &lt;0.05). M. Stenopetala (50 mg/ml) extract reduced monoamine oxidase and acetylcholinesterase activity more than M. oleifera. Compared to the paraquat‐induced group, M. Stenopetala also increased the amounts of superoxide dismutase, glutathione‐S‐transferase, catalase, and total thiols. Gene expression data show that the induced group had lower levels of catalase and TH mRNA expression compared to the treated groups. It was shown that M. oleifera had a greater ameliorative impact than M. stenopetala on catalase mRNA expression, whereas M. stenopetala had a considerably greater ameliorative effect on TH mRNA expression than M. oleifera.ConclusionIn this research, paraquat‐induced fruit flies were treated with alkaloid extracts from Moringa leaves, and the results showed that the M. Stenopetala variety had a more effective therapeutic effect than M. oleifera.