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This paper presents a single-chip bits-to-antenna transmitter (TX) for >100 Gbps in 45nm CMOS SOI. The construction of the 64QAM constellation is achieved directly in the RF domain by utilizing three QPSK sub-TXs with weighted amplitude. This method significantly reduces the need to address power amplifier nonlinear effects in high-order modulation, thereby creating room for TX enhancements in both bandwidth and output power. To further improve TX performance, multi-step phase alignment strategies, and a local oscillator leakage suppression technique have been incorporated. With 40-GHz RF bandwidth, the RF-64QAM TX prototype is able to achieve a measured data rate of 120 Gbps with 15dBm effective isotropic radiated power (EIRP).

Copyright of Journal of Xi'an Jiaotong University is the property of Editorial Office of Journal of Xi'an Jiaotong University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a modified current-mode vertical-cavity surface-emitting laser (VCSEL) driver as a transmitter for short-range light detection and ranging (LiDAR) sensors, where a stable bias generator is suggested with a regulated cascode current mirror circuit to provide the bias current of 1 mA with a trivial deviation of 5.4%, even at the worst-case process–voltage–temperature (PVT) variations. Also, a modified current-steering logic circuit is exploited with N-type MOSFET (NMOS) switches to deliver the modulation currents of 0.1~10 mApp to the VCSEL diode simultaneously, with no overshoot distortions. Post-layout simulations of the modified current-mode VCSEL driver (m-CMVD), using 180 nm CMOS technology, demonstrate very large and clean output pulses with significantly reduced signal distortions. Hereby, the VCSEL diode is transformed into an equivalent circuit with a 1.6 V DC voltage and a 50 Ω resistor for circuit simulations. The proposed m-CMVD consumes a maximum of 11 mW from a 3.3 V supply voltage and the chip core occupies an area of 0.196 mm2. [ABSTRACT FROM AUTHOR]

Copyright of Informacije MIDEM: Journal of Microelectronics, Electronic Components & Materials is the property of MIDEM Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Marine controlled source electromagnetic (MCSEM) method is widely used to reveal the electrical structure of shallow media below the seafloor. It is an indispensable geophysical means in the exploration of marine oil and gas exploration, natural gas hydrates and seafloor geological structures. The transmitter and receiver in electromagnetic detection equipment need to maintain a high temporal consistency, usually using high-stability pulse-per-second (PPS) generated by GPS or BeiDou navigation modules as a synchronization signal. Coaxial cable is a widely used tow cable, so it is necessary to design a clock synchronization method of marine controlled source electromagnetic transmitter using coaxial cable. This paper proposes a method for synchronizing the internal clocks of the transmitter with PPS using ship-borne power supply when coaxial cable is used as tow cable. In this method, the ship-borne high-power supply outputs a high-voltage AC signal that is synchronized with the 400 Hz signal output from GPS; the coaxial cable transmits AC high power electrical energy and control commands; the AC signal transmitted via the coaxial cable is converted into a stable and continuous 1 Hz signal by step-down, waveform shaping and frequency division for synchronizing the internal time pulses of the transmitter. The test result shows that the 1 Hz signal obtained by this method has a deviation of about 504 ns relative to the PPS. This deviation meets the need of MCSEM transmitter for clock synchronization. [ABSTRACT FROM AUTHOR]

Terahertz waves have the characteristics of low energy and good transmittance, which have broad application prospects in communication, spectral detection of biological samples, radar imaging, and sensing. Conventional materials are difficult to interact with terahertz waves, and metamaterials have emerged as a way to modulate terahertz waves. However, after years of development, the traditional metamaterials are currently facing problems such as difficult to realize multi-functionality and non-tunable. Therefore, in this paper, a multifunctional tunable terahertz metamaterial is designed using the phase change material vanadium dioxide. This device can perform both transmission and absorption functions. Controlling the temperature can realize the functional conversion of the device, and when the temperature is low (20°C), the transmittance of the device is more than 90% when it operates at 0.48 THz, with good performance of the transmission function. And after increasing the temperature above the VO2 phase transition temperature (66°C), it can be used as a narrow-band absorber with an absorption rate as high as 99.3% at 1.247 THz (80°C), which achieves a perfect absorption effect. In addition, the device is tunable, and its absorption and transmission modulation amplitudes can reach 95.3 and 89%, respectively. [ABSTRACT FROM AUTHOR]

Leishmaniasis is one of the dangerous diseases that are widespread in the world. Its vectors are mosquitoes. One of the main reasons for the significant increase in the number of leishmaniasis is that the methods of combating vectors are not widely known. It is very important to prevent the disease and determine its species composition. The article shows various methods used to catch mosquitoes. This methods are widely used in research work. When applying the used methods, care should be taken not to disturb the chemical balance and not cause changes in species composition. In the future, steps should be taken to find safer methods. [ABSTRACT FROM AUTHOR]

Abstract Enterochromaffin (EC) cells located within the intestinal mucosal epithelium release serotonin (5-HT) to regulate motility tones, barrier function and the immune system. Electroanalytical methodologies have been able to monitor steady state basal extracellular 5-HT levels but are unable to provide insight into how these levels are influenced by key regulatory processes such as release and uptake. We established a new measurement approach, amperometry approach curve profiling, which monitors the extracellular 5-HT level at different electrode–tissue (E–T) distances. Analysis of the current profile can provide information on contributions of regulatory components on the observed extracellular 5-HT level. Measurements were conducted from ex vivo murine ileum and colon using a boron-doped diamond (BDD) microelectrode. Amperometry approach curve profiling coupled with classical pharmacology demonstrated that extracellular 5-HT levels were significantly lower in the colon when compared to the ileum. This difference was due to a greater degree of activity of the 5-HT transporter (SERT) and a reduced amount of 5-HT released from colonic EC cells. The presence of an inhibitory 5-HT4 autoreceptor was observed in the colon, where a 40% increase in extracellular 5-HT was the half maximal inhibitory concentration for activation of the autoreceptor. This novel electroanalytical approach allows estimates of release and re-uptake and their contribution to 5-HT extracellular concentration from intestinal tissue be obtained from a single series of measurements.

Abstract Background External tags, such as transmitters and loggers, are often used to study bat movements. However, physiological and behavioural effects on bats carrying tags have rarely been investigated, and recommendations on the maximum acceptable tag mass are rather based on rules of thumb than on rigorous scientific assessment. Methods We conducted a comprehensive three-step assessment of the potential physiological and behavioural effects of tagging bats, using common noctules Nyctalus noctula as a model. First, we examined seasonal changes in body mass. Second, we predicted and then measured potential changes in flight metabolic rate in a wind tunnel. Third, we conducted a meta-analysis of published data to assess effects of different tag masses on the weight and behaviour of bats. Results Individual body mass of common noctules varied seasonally by 7.0 ± 2.6 g (range: 0.5–11.5 g). Aerodynamic theory predicted a 26% increase in flight metabolic rate for a common noctule equipped with a 3.8 g tag, equating to 14% of body mass. In a wind tunnel experiment, we could not confirm the predicted increase for tagged bats. Our meta-analysis revealed a weak correlation between tag mass and emergence time and flight duration in wild bats. Interestingly, relative tag mass (3–19% of bat body mass) was not related to body mass loss, but bats lost more body mass the longer tags were attached. Notably, relatively heavy bats lost more mass than conspecifics with a more average body mass index. Conclusion Because heavy tags (> 3 g) were generally used for shorter periods of time than lighter tags (~ 1 g), the long-term effects of heavy tags on bats cannot be assessed at this time. Furthermore, the effects of disturbance and resource distribution in the landscape cannot be separated from those of tagging. We recommend that tags weighing 5–10% of a bat’s mass should only be applied for a few days. For longer studies, tags weighing less than 5% of a bat's body mass should be used. To avoid adverse effects on bats, researchers should target individuals with average, rather than peak, body mass indices.

Background: External tags, such as transmitters and loggers, are often used to study bat movements. However, physiological and behavioural effects on bats carrying tags have rarely been investigated, and recommendations on the maximum acceptable tag mass are rather based on rules of thumb than on rigorous scientific assessment. Methods: We conducted a comprehensive three-step assessment of the potential physiological and behavioural effects of tagging bats, using common noctules Nyctalus noctula as a model. First, we examined seasonal changes in body mass. Second, we predicted and then measured potential changes in flight metabolic rate in a wind tunnel. Third, we conducted a meta-analysis of published data to assess effects of different tag masses on the weight and behaviour of bats. Results: Individual body mass of common noctules varied seasonally by 7.0 ± 2.6 g (range: 0.5–11.5 g). Aerodynamic theory predicted a 26% increase in flight metabolic rate for a common noctule equipped with a 3.8 g tag, equating to 14% of body mass. In a wind tunnel experiment, we could not confirm the predicted increase for tagged bats. Our meta-analysis revealed a weak correlation between tag mass and emergence time and flight duration in wild bats. Interestingly, relative tag mass (3–19% of bat body mass) was not related to body mass loss, but bats lost more body mass the longer tags were attached. Notably, relatively heavy bats lost more mass than conspecifics with a more average body mass index. Conclusion: Because heavy tags (> 3 g) were generally used for shorter periods of time than lighter tags (~ 1 g), the long-term effects of heavy tags on bats cannot be assessed at this time. Furthermore, the effects of disturbance and resource distribution in the landscape cannot be separated from those of tagging. We recommend that tags weighing 5–10% of a bat's mass should only be applied for a few days. For longer studies, tags weighing less than 5% of a bat's body mass should be used. To avoid adverse effects on bats, researchers should target individuals with average, rather than peak, body mass indices. [ABSTRACT FROM AUTHOR]

Background: GPS-transmitters enable detailed study of animal behaviour but may impact the animals. Impacts vary from short-term stress and habituation to longer-term effects on e.g., migration and reproduction. To study impacts, ideally, true controls (i.e., uncaptured or untagged animals) are used, but unbiased assessments of their migration timing and breeding performance are challenging, especially in remote areas. Alternatively, quasi-controls can be used: individuals tagged longer ago, or the same tagged individuals but in later years. Quasi-controls reveal tagging effects that differ between the first and following years. Results: We captured Pink-footed geese (Anser brachyrhynchus) in spring and summer and deployed GPS-transmitter neckbands. In spring, geese were caught with cannon or clap nets on stopovers in Norway and Finland, 2 weeks before departure to breeding areas in Svalbard and Novaya Zemlya. In summer, geese were rounded up during wing moult in Svalbard. First, we compared geese tagged recently in spring with geese tagged in spring or summer 1–4 years prior. Newly tagged geese migrated significantly later, by 2 days, than previously tagged geese, both at departure from the spring stopover and arrival to the breeding grounds, while migration duration did not differ. Breeding propensity and laying date did not differ, but nesting success tended to be lowered, resulting in a significantly lower annual probability to produce hatchlings in recently tagged geese than in previously tagged geese. Second, within individuals tagged in spring, spring migration advanced in their next year, suggesting delay in their first spring. This was likely not an ageing effect, as geese tagged in summer showed no advancing spring migration timing over the years. Third, in Svalbard, observed brood sizes of geese tagged in summer and untagged geese did not differ 1 year after tagging. Conclusions: The capture and GPS-tagging of geese 2 weeks before spring departure delayed their spring migration and lowered their probability to produce hatchlings in that year. These effects lasted longer than previously reported week-long effects of GPS-tagging on time budgets in summer and of neck-banding on spring body condition. Additional study is needed to evaluate longer-term or permanent effects which remain undetected with quasi-controls. [ABSTRACT FROM AUTHOR]

With the advent of fifth Generation of cellular communication with its key features that superior over all the precedent generations. However, there are some challenges need to be taken into consideration. The main crucial part of communication system is the receiver and as it is known there are two main types of receivers which can be used to demodulate the signals and recover the transmitted data. In this paper, we used those two types of algorithm receivers which are the Non-Coherent and Coherent receivers. They are firstly demonstrated in details in accordance with receiver specification design and then moved to the practical side of implementation. In which novelty of our work is highlighted, by carrying out those different algorithms on the ADSP 21364 SHARC board where initially sampling the received DPSK signal, design the Bandpass and lowpass digital filtering respectively and all to be compiled by Analog Devices VisualDSP + + software that is programmed by C language prior to download to the ADSP Board chip. The same algorithm is followed in the frame synchronization for both of them by detecting the message through distinguishing the preamble of the message " + + + + " data which is before the 72 bytes (real message).Then that actual message will be stored and dumped to the memory and displayed to ensure from the received message whether it is corrupted with errors or not. However, it is clearly noticed that the Coherent receiver is more efficient than the Non-coherent, but it still a bit expensive because used double look-up tables for cosine and sine in IQ converter. Finally, coherent receiver with Costas loop algorithm was implemented as well to improve the previous differential detection scheme. [ABSTRACT FROM AUTHOR]

A low-power transmitter driver for chiplet interconnection was designed and experimentally implemented based on the interchip interconnection standard proposed by the UCIe protocol. The driver circuit adopts a source series terminated (SST) diver, whose power consumption is only 1/4 that of the current mode logic (CML) structure. In add-on, based on adjustable feedforward equalization technology, the driver circuit adjusts the equalization strength for different channel attenuations. By de-emphasizing equalization, it enhances the quality of the transmitted signal, ultimately reducing inter-symbol interference. This circuit was designed under CMOS 28 nm process. The front-end simulation results show that the maximum equalization intensity is --3. 7 dB when the 0. 9 V voltage is supplied. When the 32 Gbps NRZ signal passes through the 21 mm channel (the attenuation at the 16 GHz Nyquist frequency is --2. 37 dB), after adjusting the appropriate equalization intensity, the eye height of the output waveform eye diagram is 253 mV (71.8%), the eye width is 27 ps (87%), and the simulation power consumption is only 4. 0 mW. [ABSTRACT FROM AUTHOR]

Several circuit components can induce bit errors at high-speed wireline interfaces. Hence, accurate identification and correction of error points in various circuits using straightforward techniques are crucial. A serializer in the transmitter may experience abnormal operations due to a timing mismatch between data and clock signals, leading to bit errors. Hence, we propose a debugging circuit to address this challenge for detecting timing mismatches between input data and clock signals within the tri-state inverter-based 2:1 serializer with a half-rate clocking architecture. The debugging circuit uses a true single-phase clocked (TSPC) DFF, TSPC latch, and XOR gate, which are simple complementary metal-oxide-semiconductor (CMOS) logics, and did not necessitate additional pads or experimental equipment, resulting in minimal area occupation and low power consumption. Using identical data and clock signals with the 2:1 serializer, the timing relationship between the data and clock signals can be detected. Unlike complex debugging methods that rely on intricate algorithms and extensive programming, our approach simplifies debugging, reducing test time. We developed a prototype transmitter using a 28-nm CMOS process to validate the effectiveness of our proposed solution. The 2:1 serializer was designed to function correctly or not by manually adjusting the input clock phase for testability. The proposed debugging circuit effectively detected timing mismatches in the serializer at speeds up to 7.5 Gb/s. The circuit occupied only 0.4% of the total area and consumed only 0.2% of the total transmitter power.

Battery management systems (BMS) in electric vehicles (EVs) require robust communication interfaces to accurately monitor and control lithium-ion battery cells. The communication interface of daisy chain architecture has attracted more and more attention because of its lower deployment cost compared with the communication architecture of the controller area network (CAN). However, in automotive electronics, in order to meet safety standards, it is difficult to implement circuits that are highly robust to electromagnetic interference, which has also attracted many practitioners to study it. The problem of partial electromagnetic interference and clock jitter can be addressed not only by employing methods commonly used in the field of analog signals, but also by leveraging algorithms utilized in the domain of digital signals. This paper proposes an EMI-immune daisy chain interface circuit with a PID-based clock-data-recovery (CDR) algorithm, utilizing either a capacitor or a transformer as an isolator. The system includes a transmitter, an active receiver, a wake-up receiver, and the corresponding algorithm digital circuits, achieving a successful transmission under 39-dBm DPI injection. Simulation results demonstrate a CMTI of 100kV/ $\mu $ s and low power consumption. The proposed CDR algorithm enables effective operation in the presence of clock frequency offset and EMI between chips. This paper thoroughly examines the underlying principles of the algorithm, supplemented by comprehensive test environments and accompanying data visuals.

This paper presents a Ka-band beam steering transmitter exploiting a coupled varactor loaded transmission line (VLTL) phase shifter and a CMOS transmitter chip with an integrated frequency multiplier. The short-coupled line couplers placed along a single VLTL provides multi-phase outputs while minimizing the impedance mismatch and unequal power distribution along the VLTLs. The inherent phase-accumulating nature along the VLTL reduces the burden of wide phase control range required for using separate phase shifters for each channel. Additionally, the frequency multiplier with a multiplication ratio of 8 reduces the required amount of phase change at the reference frequency and therefore the tuning range of the varactor, which also minimize a change of line characteristic impedance to ensure the impedance matching of the VLTL. Hence, a 32 GHz phased array transmitter is implemented using a single VLTL phase shifter operating at a low reference frequency of about 4 GHz. The fabricated $1\times 4$ phased array transmitter achieves a continuous beam steering range of ±20° in the E-plane using a single control voltage. The sidelobe level is below -10 dB at all scan angles and the peak effective isotropic radiated power (EIRP) is 38.1 dBm at 31.6 GHz and the 3-dB bandwidth of 2.4 GHz is achieved.

This paper presents a modified current-mode vertical-cavity surface-emitting laser (VCSEL) driver as a transmitter for short-range light detection and ranging (LiDAR) sensors, where a stable bias generator is suggested with a regulated cascode current mirror circuit to provide the bias current of 1 mA with a trivial deviation of 5.4%, even at the worst-case process–voltage–temperature (PVT) variations. Also, a modified current-steering logic circuit is exploited with N-type MOSFET (NMOS) switches to deliver the modulation currents of 0.1~10 mApp to the VCSEL diode simultaneously, with no overshoot distortions. Post-layout simulations of the modified current-mode VCSEL driver (m-CMVD), using 180 nm CMOS technology, demonstrate very large and clean output pulses with significantly reduced signal distortions. Hereby, the VCSEL diode is transformed into an equivalent circuit with a 1.6 V DC voltage and a 50 Ω resistor for circuit simulations. The proposed m-CMVD consumes a maximum of 11 mW from a 3.3 V supply voltage and the chip core occupies an area of 0.196 mm2.

Copyright of Bulletin de la Societe Zoologique de France is the property of Societe Zoologique de France and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The VLSI integration technology is growing at a rapid rate. As a result, there is a need for smart devices with high performance operation. This plays a vital role in the consumer industry at larger scale in day-to-day life. To enhance performance of the new devices, more robust interfacing standards are required. Hence, the proposed paper discusses the design of the I/O standard LVCMOS18 buffer with 0.9V interface at the transmitter with an operating frequency of 150 MHz. The interface I/O design uses 90nm GPDK technology and is tested with various process corners with 4 mA current drive capability. The results obtained are found to be encouraging for all the design specifications of LVCMOS 18 I/O standard for the transmitter. [ABSTRACT FROM AUTHOR]

Background: This study investigates Light Fidelity (Li-Fi) as a possible route for data transmission, particularly given the rapid rise of the Internet of Things (IoT). Given Wi-Fi's vulnerability to interference, hacking, and worries about electromagnetic radiation (EMR) health effects, Li-Fi's potential benefits over regular Wi-Fi were especially appealing. Objective: Determine the effectiveness of Li-Fi in delivering audio data. This included building a rudimentary Li-Fi circuit to carry audio data and testing its speed, security, and dependability. Methods: In the research, audio signals were converted to optical signals using a Li-Fi-based circuit. This was sent across a network. The efficiency and sustainability of solar panels were investigated. To secure transmitted data, advanced encryption was also tried. Results: The findings underlined li-Fi's improved performance, particularly in situations of high network traffic. This advantage is due to Li-Fi's use of light waves for data transport, which are less sensitive to interference than traditional radio frequency-based solutions. This study's basic Li-Fi circuit acted as a proof of concept in audio data transfer, highlighting the potential advantages of enhanced audio quality and increased security. Conclusion: Given the rising needs of IoT, Li-Fi appears as a viable competitor for future Internet infrastructure. The study highlights the benefits of Li-Fi while emphasizing the need for ongoing research and technological advances to fully realize its potential in various applications

The trigger transceiver and timing control system described in this study is developed to generate multiple triggers with varying delays to synchronize various subsystems with plasma discharges in the ADITYA Upgrade (ADITYA-U) tokamak (Ghosh et al., 2016) [1]. The Toroidal Field Power Supply (TFPS) is a fundamental component for each plasma discharge in the ADITYA-U, which generates a master trigger pulse for the particular discharge. The rise time of Toroidal Field Power Supply is 2 s and the loop voltage which is required to initiate the plasma discharge begins at 2.4 s after the master trigger. So the loop voltage is time-stamped at t = 0 and the master trigger from TFPS is time-stamped at t = −2.4 s and considered as a pre-trigger. Apart from this master trigger at t = −2.4 s, two more pre-trigger pulses, one at ∼ −40 ms and another at ∼ −4 ms, prior to the initiation of loop voltage trigger are generated by the power supply. These pre-trigger pulses generated by TFPS constitute the backbone of the entire discharge timing sequence, and they operate/control/initiate numerous ADITYA-U subsystems such as the gas puffing system, data acquisition system, radio frequency pre-ionization and heating system, plasma position control, and so on. So a suitable trigger generator system was needed to be developed in which three pre-trigger pulses (time stamped @ −2.4 s, −40 ms, and −4 ms prior to the loop voltage trigger) arriving from the TFPS may be selected and altered based on the experimental needs. To cater these requirements in ADITYA-U, a trigger transceiver and timing control system has been developed. The system has been successfully operated over ∼6000 discharges of ADITYA-U and functioned satisfactorily in all discharges in daily experiments with no failures. This study will discuss the detailed design elements and implementation of the Trigger Transceiver and Timing Control System for ADITYA-U plasma operations. [ABSTRACT FROM AUTHOR]

This paper presents a novel, digitally configurable, switching oscillator-based impulse radio ultra-wideband (IR-UWB) transmitter that is robust to process variations. The pulse width and pulse position properties of the output waveform are configurable to ensure operation for the desired bandwidth and output pulse energy values. The architecture is based on a cross-coupled LC voltage-controlled oscillator (LC VCO) implemented with a custom-designed on-chip balun at a center frequency of 2.4 GHz. With the usage of this on-chip balun, the need for an extra buffer stage is eliminated, and the highest possible efficiency is achieved with the proper turns ratio selected. The generated digital control pulse signals are also used to ensure fast start-up and UWB operation while maintaining low power consumption with an implemented on/off tail switching scheme. The presented IR-UWB transmitter that occupies a total area of 0.35 mm2 is fabricated in the United Microelectronics Corporation (UMC) 180-nm mixed-mode/radio frequency (RF) CMOS process. The measured output voltage swing of the fabricated transmitter is 0.812 V on a 50- Ω load for the 200 Mb/s data rate, and the bandwidth is measured as 902 MHz. The achieved frequency tuning range is 1 GHz and the fabricated transmitter can drive 50 Ω , 75 Ω and 100 Ω loads with measured efficiency values 4.16%, 5.76%, and 4.05%, respectively. Compared to other works in the literature, this design achieves a higher output pulse energy at a higher data rate while maintaining low power consumption and, thus, high efficiency. • IR-UWB transmitter that features configurable pulse width, pulse position, and center frequency settings, designed to withstand PVT variations. • A custom-designed balun designed for maximum efficiency, eliminating the necessity for an output stage to drive a 50- Ω , 75- Ω , or 100- Ω loads. • Achieving high efficiency through the combination of high data rate and large output voltage swing while maintaining low power consumption. • Fast start-up and shutdown using configurable charge injection and charge removal from the output of the oscillator circuit. [ABSTRACT FROM AUTHOR]

This paper presents a 10 bits low-power direct digital IF to RF digital-to-analog (RF-DAC) fabricated in a 110 nm CMOS technology with a core area of 0.08 mm 2. The DAC uses sixteen current mode double balanced mixers designed without a tail transistor with different weights to convert IF output to RF output. The digital IF signal is modulated by a digital Σ − Δ modulator with 1-bit IF output. The RF-DAC with a bandwidth of 300 KHz consumes 17.3 mA from a 1.5 V supply. [ABSTRACT FROM AUTHOR]

Deuterostome invertebrates, including echinoderms, hemichordates, cephalochordates, and urochordates, exhibit common and species-specific morphological, developmental, physiological, and behavioral characteristics that are regulated by neuroendocrine and nervous systems. Over the past 15 years, omics, genetic, and/or physiological studies on deuterostome invertebrates have identified low-molecular-weight transmitters, neuropeptides and their cognate receptors, and have clarified their various biological functions. In particular, there has been increasing interest on the neuroendocrine and nervous systems of Ciona intestinalis Type A, which belongs to the subphylum Urochordata and occupies the critical phylogenetic position as the closest relative of vertebrates. During the developmental stage, gamma-aminobutylic acid, D-serine, and gonadotropin-releasing hormones regulate metamorphosis of Ciona. In adults, the neuropeptidergic mechanisms underlying ovarian follicle growth, oocyte maturation, and ovulation have been elucidated. This review article provides the most recent and fundamental knowledge of the neuroendocrine and nervous systems of Ciona , and their evolutionary aspects. • Deuterostomes possess a variety of endocrine, neuroendocrine, and nervous systems. • Ciona , a deuterostome invertebrate, is the closest relative of vertebrates. • Metamorphosis is regulated by neurotransmitters and neuropeptides in Ciona larva. • Ovarian follicle development in Ciona adults is regulated by neuropeptides. • Recent studies highlight common and unique neuroendocrine and nervous systems of Ciona in deuterostomes. [ABSTRACT FROM AUTHOR]

Enterochromaffin (EC) cells located within the intestinal mucosal epithelium release serotonin (5-HT) to regulate motility tones, barrier function and the immune system. Electroanalytical methodologies have been able to monitor steady state basal extracellular 5-HT levels but are unable to provide insight into how these levels are influenced by key regulatory processes such as release and uptake. We established a new measurement approach, amperometry approach curve profiling, which monitors the extracellular 5-HT level at different electrode-tissue (E-T) distances. Analysis of the current profile can provide information on contributions of regulatory components on the observed extracellular 5-HT level. Measurements were conducted from ex vivo murine ileum and colon using a boron-doped diamond (BDD) microelectrode. Amperometry approach curve profiling coupled with classical pharmacology demonstrated that extracellular 5-HT levels were significantly lower in the colon when compared to the ileum. This difference was due to a greater degree of activity of the 5-HT transporter (SERT) and a reduced amount of 5-HT released from colonic EC cells. The presence of an inhibitory 5-HT 4 autoreceptor was observed in the colon, where a 40% increase in extracellular 5-HT was the half maximal inhibitory concentration for activation of the autoreceptor. This novel electroanalytical approach allows estimates of release and re-uptake and their contribution to 5-HT extracellular concentration from intestinal tissue be obtained from a single series of measurements., (© 2024. The Author(s).)