BACKGROUND:The mechanisms underlying heat stroke(HS)-induced hippocampal injury remain unclear.This study aimed to evaluate the HS-induced metabonomics of hippocampal and cerebellar transmitters.METHODS:The HS model w...BACKGROUND:The mechanisms underlying heat stroke(HS)-induced hippocampal injury remain unclear.This study aimed to evaluate the HS-induced metabonomics of hippocampal and cerebellar transmitters.METHODS:The HS model was established with male Sprague-Dawley rats subjected to heat exposure of up to 42℃ at a humidity of(55.0±5.0)%.The hippocampal and cerebellar transmitters and metabolites of rats were tested via ultra-high-performance liquid chromatography–mass spectrometry(UPLC-MS/MS).The primary transmitters and metabolites were identified by principal component analysis(PCA)and orthogonal partial least square-discriminant analysis(OPLS-DA).The major metabolic pathways for HS were selected after enrichment.The brain injury was evaluated by histological tests.RESULTS:HS induced hippocampal and cerebellar injuries in rats.HS upregulated the protein levels of hippocampal glutamate,glutamine,gamma-aminobutyric acid,L-tryptophan(Trp),5-hydroxy-indoleacetic acid,and kynurenine;however,it downregulated asparagine,tryptamine,5-hydroxytryptophan,melatonin,3,4-dihydroxyphenylalanine(L-DOPA),and vanillylmandelic acid.HS also sharply elevated the protein levels of cerebellar methionine and Trp,and decreased the levels of serotonin,L-alanine,L-asparagine,L-aspartate,cysteine,norepinephrine,spermine,spermidine,and tyrosine.Hippocampal glutamate,monoamine transmitters,cerebellar aspartate acid,and catecholamine transmitters’metabolic pathways were identified as the main metablic pathways in HS.CONCLUSION:The hippocampus and cerebellum were injured in rats with HS,possibly induced the disorder of hippocampal glutamate and serotonin metabolism,cerebellar aspartate acid and catecholamine transmitter metabolism,and related metabolic pathways.展开更多
We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool(AABT),which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and ...We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool(AABT),which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and field tests to verify the AABT tool.The numerical simulation results showed that the radiation direction of the subarray corresponding to the maximum amplitude of the first arrival matches the azimuth of the channeling when it is behind the casing.With larger channeling size in the circumferential direction,the amplitude difference of the casing wave at different azimuths becomes more evident.The test results showed that the AABT can accurately locate the casing collars and evaluate the cement bond quality with azimuthal resolution at the casing-cement interface,and can visualize the size,depth,and azimuth of channeling.In the case of good casingcement bonding,the AABT can further evaluate the cement bond quality at the cementformation interface with azimuthal resolution by using the amplitude map and the velocity of the formation wave.展开更多
2.5 Gbit/s monolithic integrated circuits (ICs) for optical fiber transmitter and receiver in 0.35 μm CMOS (complementary metal-oxide-semiconductor transistor) process are presented. The transmitter, which includ...2.5 Gbit/s monolithic integrated circuits (ICs) for optical fiber transmitter and receiver in 0.35 μm CMOS (complementary metal-oxide-semiconductor transistor) process are presented. The transmitter, which includes a 4: 1 multiplexer and a laser diode driver (LDD), has four 622 Mbit/s random signals as its inputs and gets a 2.5 Gbit/s driving signal as its output; the receiver detects a 2.5 Gbit/s random signal and gets four 622 Mbit/s signals at the output. The main circuits include a trans-impedance amplifier (TIA), a limiting amplifier, a clock and data recovery (CDR) unit, and a 1: 4 demultiplexer (DEMUX). Test results prove the logic functions of the transmitter to be right, and the 10% to 90% rise and fall times of transmitter's output data eye diagram are 211.1 ps and 200 ps, respectively. The sensitivity of the receiver is measured to be better than 20 mV. The root mean square jitter of the DEMUX's output data is 15.6 ps and that of the clock after 1: 4 frequency dividing is 1.9 ps. Two chips are both applicable to 2.5 Gbit/s optical fiber communication systems.展开更多
A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodiffere...A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts: a 20MHz ASK modulator based on a constant amplitude phase lock loop (PLL) and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.展开更多
The dopaminergic system controls several vital central nervous system functions, including the control of movement, reward behaviors and cognition. Alterations of dopaminergic signaling are involved in the pathogenesi...The dopaminergic system controls several vital central nervous system functions, including the control of movement, reward behaviors and cognition. Alterations of dopaminergic signaling are involved in the pathogenesis of neurodegenerative and psychiatric disorders, in particular Parkinson’s disease, which are associated with a subtle and chronic inflammatory response. A substantial body of evidence has demonstrated the non-neuronal expression of dopamine, its receptors and of the machinery that governs synthesis, secretion and storage of dopamine across several immune cell types. This review aims to summarize current knowledge on the role and expression of dopamine in immune cells. One of the goals is to decipher the complex mechanisms through which these cell types respond to dopamine, in order to address the impact this has on neurodegenerative and psychiatric pathologies such as Parkinson’s disease. A further aim is to illustrate the gaps in our understanding of the physiological roles of dopamine to encourage more targeted research focused on understanding the consequences of aberrant dopamine production on immune regulation. These highlights may prompt scientists in the field to consider alternative functions of this important neurotransmitter when targeting neuroinflammatory/neurodegenerative pathologies.展开更多
Multi-lane integrated transmitter chips are key components in future compact optical modules to realize high-speed optical interconnects.Thin-film lithium niobate(TFLN)photonics have emerged as a promising platform fo...Multi-lane integrated transmitter chips are key components in future compact optical modules to realize high-speed optical interconnects.Thin-film lithium niobate(TFLN)photonics have emerged as a promising platform for achieving high-performance chip-scale optical systems.Combining a coarse wavelength-division multiplexing(CWDM)devices using fabrication-tolerant angled multimode interferometer structure and high-performance electro-optical modulators,we demonstrate monolithic on-chip four-channel CWDM transmitter on the TFLN platform for the first time.The four-channel CWDM transmitter enables high-speed transmissions of 100 Gb/s data rate per wavelength channel(i.e.,an aggregated date rate of 400 Gb/s).展开更多
An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling envir...An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling environments with high temperature and pressure, as well as strong collar drilling vibration during the drilling process. Aimed to improve the transmitting performance, numerical and experimental studies for the transducer optimization are conducted. The impact of location and length of the piezoelectric stack on resonance characteristics arid effective electromeehanical coupling coefficient is calculated and analyzed. Admittance and transmitting performance of the proposed transducer are measured in laboratory experiments, and the results are compared with simulated ones. It is shown that the newly proposed transducer has higher transmitting performance with lower resonance frequencies. This work provides theoretical and experimental bases for transducer designing and acoustic wave measurements in acoustic logging, especially in acoustic logging while drilling.展开更多
The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware...The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware resources and have long la-tency.To further meet the 5G and future 6G commu-nication requirements,this paper proposes a novel di-rect digital synthesis(DDS)based OFDM transmitter structure that can replace these modules.Due to the strong parallelism of the system structure,it is very suitable for implementation on field programable gate array(FPGA)platform.After making two special sim-plifications to the primary structure,the refined struc-ture becomes very simple compared with the tradi-tional structures.Most attractively,the proposed struc-ture has the following three advantages that i)the data transformation from frequency domain to time domain has zero latency,ii)the transformation length does not need to be an integer power of 2 and iii)the struc-ture does not even need to use any multiplier,thus leading to low implementation complexity and high speed.Comparative experiments are carried out on Intel FPGA platform which show that our DDS based structure can save more than half of the resources com-pared with the traditional structures and can provide the same bit error rate(BER)performance under the condition without using any LPSF.展开更多
Non-collaborative radio transmitter recognition is a significant but challenging issue, since it is hard or costly to obtain labeled training data samples. In order to make effective use of the unlabeled samples which...Non-collaborative radio transmitter recognition is a significant but challenging issue, since it is hard or costly to obtain labeled training data samples. In order to make effective use of the unlabeled samples which can be obtained much easier, a novel semi-supervised classification method named Elastic Sparsity Regularized Support Vector Machine (ESRSVM) is proposed for radio transmitter classification. ESRSVM first constructs an elastic-net graph over data samples to capture the robust and natural discriminating information and then incorporate the information into the manifold learning framework by an elastic sparsity regularization term. Experimental results on 10 GMSK modulated Automatic Identification System radios and 15 FM walkie-talkie radios show that ESRSVM achieves obviously better performance than KNN and SVM, which use only labeled samples for classification, and also outperforms semi-supervised classifier LapSVM based on manifold regularization.展开更多
In this paper,we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory.In this work,to study the small range of tempera...In this paper,we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory.In this work,to study the small range of temperature(40-100℃)although different temperature sensors can be used still,we have used here a K-type thermocouple as the measuring temperature sensor.The analog output voltage of thermocouple is amplified by instrumentation amplifier and the amplified signal is fed to the analog input of NI myRIO device which converts the analog input voltage signal as per the algorithm developed with virtual instrumentation based programming and provides the corresponding 4-20 mA output current signal in the analog output terminal of the device.Results show that input-output i.e.temperature-current relationship is linear.This low cost developed transmitter is very simple and it can be recommended for academic,scientific and industrial development of data acquisition systems,control and analysis of instruments.展开更多
This paper presents the experimental results of a low-power RF transmitter for 2.4-GHz-band IEEE 802.15.4 standard in 0.18-μm CMOS technology. In order to make an adaptive RF transmitter, several factors must be cons...This paper presents the experimental results of a low-power RF transmitter for 2.4-GHz-band IEEE 802.15.4 standard in 0.18-μm CMOS technology. In order to make an adaptive RF transmitter, several factors must be considered. The most important factors are performances, power consumption, output power, noise factor, and cost. The RF transmitter comprises a quadrature passive mixer, and a power amplifier. The proposed RF transmitter consumes only 10.8-mW under a supply voltage of 1.8-V.展开更多
This study compared three surgical techniques to implant acoustic transmitters in rainbow trout (</span><i><span style="font-family:Verdana;">Oncorhynchus mykiss</span></i><s...This study compared three surgical techniques to implant acoustic transmitters in rainbow trout (</span><i><span style="font-family:Verdana;">Oncorhynchus mykiss</span></i><span style="font-family:Verdana;">): 1</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">)</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> acoustic transmitter insertion via a ventral incision closed with two sutures, 2</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">)</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> insertion via a ventral incision with no sutures, 3</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">)</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> insertion via a lateral incision with no sutures. A control group consisting of fish that were only anesthetized and handled was also included. Tag retention, wound healing, inflammation, growth, and survival were recorded over a 12</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">week period. Tag retention was significantly different among the treatments, at 100% in the unsutured ventral incision group, 89% in the lateral incision group, and 63% in the sutured ventral incision group. Surgical wounds in the unsutured treatment groups showed significantly less inflammation than the sutured treatment. Wound closure occurred significantly faster in the ventral incision groups compared to the lateral incision group. The results of this study show the utility of using unsutured surgical methods for implanting acoustic transmitters in rainbow trout.展开更多
The present work deals with 12-bit Nyquist current-steering CMOS digital-to-analog converter (DAC) which is an essential part in baseband section of wireless transmitter circuits. Using oversampling ratio (OSR) for th...The present work deals with 12-bit Nyquist current-steering CMOS digital-to-analog converter (DAC) which is an essential part in baseband section of wireless transmitter circuits. Using oversampling ratio (OSR) for the proposed DAC leads to avoid use of an active analog reconstruction filter. The optimum segmentation (75%) has been used to get the best DNL and reduce glitch energy. This segmentation ratio guarantees the monotonicity. Higher performance is achieved using a new 3-D thermometer decoding method which reduces the area, power consumption and the number of control signals of the digital section. Using two digital channels in parallel, helps reach 1-GSample/s frequency. Simulation results show that the spurious- free-dynamic-range (SFDR) in Nyquist rate is better than 64 dB for sampling frequency up to 1-GSample/s. The analog voltage supply is 3.3 V while the digital part of the chip operates with only 2.4 V. Total power consumption in Nyquist rate measurement is 144.9 mW. The chip has been processed in a standard 0.35 μm CMOS technology. Active area of chip is 1.37 mm2.展开更多
The implantation of acoustic transmitters into the peritoneal cavity of fish is typically performed by experienced surgeons. This study compared the effectiveness of an experienced and inexperienced surgeon performing...The implantation of acoustic transmitters into the peritoneal cavity of fish is typically performed by experienced surgeons. This study compared the effectiveness of an experienced and inexperienced surgeon performing two different types of transmitter insertion techniques on rainbow trout (<i>Oncorhynchus</i> <i>mykiss</i>). The methods used were either a traditional sutured ventral incision or a novel unsutured lateral incision. There was no significant difference in surgical duration, tag retention, or fish survival between the experienced and na<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">ï</span>ve surgeon. The time to complete surgical wound closure was not significantly different between the fish operated on by an experienced or na<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">ï</span>ve surgeon, and surgeon experience had no significant effect on the duration of inflammation. However, there were significant differences between the two surgical techniques, regardless of surgeon experience. The ventral incision with sutures method took approximately three times longer to complete than the lateral incision-only method. However, complete wound closure was significantly faster in the sutured ventral incision treatment compared to the unsutured lateral treatment. Post-surgery inflammation was over seven times longer in the fish with sutures compared to those only receiving a lateral incision. Tag retention was not significantly different between the two surgical methods. The results of this study indicate that the unsutured lateral surgical technique used in this experiment can be completed with minimal training and surgical experience in contrast to the standard technique requiring su<span>tures. These results also provide additional support to the use of sutureless</span> surgical techniques for acoustic transmitter implantation.展开更多
In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice ...In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice with "yang deficiency" were studied. 30 mice were randomly divided into three groups: the normal group, the peng deficiency control group and the moxibustion treated group. Our study found out that in the mice of yang deficienly, the atrophy of the immunt organs was prevented, the reactivity of the splenocyte and the reactivity to IL - 2 were heightened, the amounts of the DA, NE and E in brain were increased significantly after moxibustion on the Point Shengshu. It can be held that moxibustion may protect the immune organs and regulate the immunity of the mouse with yang deficienly, and the effects may be contributed to the increase of the nervous transmitters in the brain.展开更多
The present study aimed at the investigation of the changes of electrocardiogram (ECG) and monoamine transmitters in brainstem of rats with acute myocardial ischemia (AMl) with electroacupuncture (EA) at Neiguan (PC 6...The present study aimed at the investigation of the changes of electrocardiogram (ECG) and monoamine transmitters in brainstem of rats with acute myocardial ischemia (AMl) with electroacupuncture (EA) at Neiguan (PC 6) and Jianshi (PC 5) treated by means of physiologic and histofluorescent and immunofluorescent methods. The results are as follows: 1. EA couId prevent ST segrnent and T wave from elevating during acute myocardial ischemia (P < 0. 05 ). 2. Monoamine-containing neurons with clear figure and bright fluoreasence, pre-and terminal axons were seen in Iocus coeruleus,lateral horn of splnal cord in two groups by the high specific sensitivity histofluorescence technique.The reaction of fluorescence was stronger in EA group than that in control one. The serotonin (5-HT) immunoreactive (ir) cells appeared in nucleus raphe (B 1, B 2). The 5-HT ir grains were more intense in EA group than that in control group. Tyrosine hydrotylase (TH) immunoreactive (ir) cell bodies were found within confines of catecholaminergic nuclei (A 1, A 2 ) of medulla. The immunofluorescence was weaker in EA group than that in control one. The results suggest that EA may regulate acute myocardial ischemia through brain stem.展开更多
An Ion Cyclotron Range of Frequency (ICRF) system with a radio frequency (RF) power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak (EAST). High RF power transmitters were de...An Ion Cyclotron Range of Frequency (ICRF) system with a radio frequency (RF) power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak (EAST). High RF power transmitters were designed as a part of the research and development (R^D) for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz. Studies presented in this paper cover the following parts of the high power transmitter: the three staged high power amplifier, which is composed of a 5 kW wide- band solid state amplifier, a 100 kW tetrode drive stage amplifier and a 1.5 MW tetrode final stage amplifier, and the DC high voltage power supply (HVPS). Based on engineering design and static examinations, the RF transmitters were tested using a matched dummy load where an RF output power of 1.5 MW was achieved. The transmitters provide 6 MW RF power in primary phase and will reach a level up to 12 MW after a later upgrade. The transmitters performed successfully in stable operations in EAST and HT-7 devices. Up to 1.8 MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved.展开更多
The structural composition, scheme selection and component design of a five-channel transmitter combiner for 800MHz trucking mobile communication system (TMC) is proposed. More attentions have been paid to the analysi...The structural composition, scheme selection and component design of a five-channel transmitter combiner for 800MHz trucking mobile communication system (TMC) is proposed. More attentions have been paid to the analysis and design of the high-Q microwave resonant cavity with accurate tuning structure. Also, a model transmitter combiner designed by the authors is proposed. Test results of the combiner are given. It has been proved that the technical specifications of the combiner have reached an advanced technical level compared with the products of the same kind imported from abroad.展开更多
In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fib...In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical isolator.The whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output efficiency.After a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was obtained.The optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured.展开更多
A 2.4 GHz high efficiency radio frequency (RF) transmitter for wireless body area network (WBAN) in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is prop...A 2.4 GHz high efficiency radio frequency (RF) transmitter for wireless body area network (WBAN) in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is proposed to achieve a high data rate with low power consumption. In conventional transmitters, the oscillator and power amplifier are turned off when the transmitter sends 0. The required time for turning oscillator ON/OFF is longer than the other blocks of the transmitter. In the proposed transmitter, the low power oscillator is on all the time while the power amplifier and modulator are turned off when"0"data is sent. The transmitter consumes 3.2 mW at 0.5 dBm output by 285 Mbps data rate and the energy consumption per transmitted bit with 0.5 dBm output power is 10 pJ/(bit-mW). The proposed transmitter was designed in 0.18 μm CMOS technology.展开更多
基金supported by the grants from Zhejiang Provincial Natural Science Foundation(LGF19H150004)Zhejiang Provincial Medical Science and Technology project(2022RC258)。
文摘BACKGROUND:The mechanisms underlying heat stroke(HS)-induced hippocampal injury remain unclear.This study aimed to evaluate the HS-induced metabonomics of hippocampal and cerebellar transmitters.METHODS:The HS model was established with male Sprague-Dawley rats subjected to heat exposure of up to 42℃ at a humidity of(55.0±5.0)%.The hippocampal and cerebellar transmitters and metabolites of rats were tested via ultra-high-performance liquid chromatography–mass spectrometry(UPLC-MS/MS).The primary transmitters and metabolites were identified by principal component analysis(PCA)and orthogonal partial least square-discriminant analysis(OPLS-DA).The major metabolic pathways for HS were selected after enrichment.The brain injury was evaluated by histological tests.RESULTS:HS induced hippocampal and cerebellar injuries in rats.HS upregulated the protein levels of hippocampal glutamate,glutamine,gamma-aminobutyric acid,L-tryptophan(Trp),5-hydroxy-indoleacetic acid,and kynurenine;however,it downregulated asparagine,tryptamine,5-hydroxytryptophan,melatonin,3,4-dihydroxyphenylalanine(L-DOPA),and vanillylmandelic acid.HS also sharply elevated the protein levels of cerebellar methionine and Trp,and decreased the levels of serotonin,L-alanine,L-asparagine,L-aspartate,cysteine,norepinephrine,spermine,spermidine,and tyrosine.Hippocampal glutamate,monoamine transmitters,cerebellar aspartate acid,and catecholamine transmitters’metabolic pathways were identified as the main metablic pathways in HS.CONCLUSION:The hippocampus and cerebellum were injured in rats with HS,possibly induced the disorder of hippocampal glutamate and serotonin metabolism,cerebellar aspartate acid and catecholamine transmitter metabolism,and related metabolic pathways.
基金supported by the National Natural Science Foundation of China(Nos.11204380,11374371,61102102,and11134011)National Science and Technology Major Project(No.2011ZX05020-009)+1 种基金China National Petroleum Corporation(Nos.2014B-4011,2014D-4105,and 2014A-3912)PetroChina Innovation Foundation(No.2014D-5006-0307)
文摘We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool(AABT),which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and field tests to verify the AABT tool.The numerical simulation results showed that the radiation direction of the subarray corresponding to the maximum amplitude of the first arrival matches the azimuth of the channeling when it is behind the casing.With larger channeling size in the circumferential direction,the amplitude difference of the casing wave at different azimuths becomes more evident.The test results showed that the AABT can accurately locate the casing collars and evaluate the cement bond quality with azimuthal resolution at the casing-cement interface,and can visualize the size,depth,and azimuth of channeling.In the case of good casingcement bonding,the AABT can further evaluate the cement bond quality at the cementformation interface with azimuthal resolution by using the amplitude map and the velocity of the formation wave.
基金The National High Technology Research and Develop-ment Program of China (863 Program) (No.2001AA312010).
文摘2.5 Gbit/s monolithic integrated circuits (ICs) for optical fiber transmitter and receiver in 0.35 μm CMOS (complementary metal-oxide-semiconductor transistor) process are presented. The transmitter, which includes a 4: 1 multiplexer and a laser diode driver (LDD), has four 622 Mbit/s random signals as its inputs and gets a 2.5 Gbit/s driving signal as its output; the receiver detects a 2.5 Gbit/s random signal and gets four 622 Mbit/s signals at the output. The main circuits include a trans-impedance amplifier (TIA), a limiting amplifier, a clock and data recovery (CDR) unit, and a 1: 4 demultiplexer (DEMUX). Test results prove the logic functions of the transmitter to be right, and the 10% to 90% rise and fall times of transmitter's output data eye diagram are 211.1 ps and 200 ps, respectively. The sensitivity of the receiver is measured to be better than 20 mV. The root mean square jitter of the DEMUX's output data is 15.6 ps and that of the clock after 1: 4 frequency dividing is 1.9 ps. Two chips are both applicable to 2.5 Gbit/s optical fiber communication systems.
文摘A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts: a 20MHz ASK modulator based on a constant amplitude phase lock loop (PLL) and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.
基金supported by a Research Development Fund(UTS Start-Up Grant 2018)from the University of Technology Sydney to AC。
文摘The dopaminergic system controls several vital central nervous system functions, including the control of movement, reward behaviors and cognition. Alterations of dopaminergic signaling are involved in the pathogenesis of neurodegenerative and psychiatric disorders, in particular Parkinson’s disease, which are associated with a subtle and chronic inflammatory response. A substantial body of evidence has demonstrated the non-neuronal expression of dopamine, its receptors and of the machinery that governs synthesis, secretion and storage of dopamine across several immune cell types. This review aims to summarize current knowledge on the role and expression of dopamine in immune cells. One of the goals is to decipher the complex mechanisms through which these cell types respond to dopamine, in order to address the impact this has on neurodegenerative and psychiatric pathologies such as Parkinson’s disease. A further aim is to illustrate the gaps in our understanding of the physiological roles of dopamine to encourage more targeted research focused on understanding the consequences of aberrant dopamine production on immune regulation. These highlights may prompt scientists in the field to consider alternative functions of this important neurotransmitter when targeting neuroinflammatory/neurodegenerative pathologies.
基金This work is supported partially by the National Major Research and Development Program(2019YFB1803902)National Natural Science Foundation of China(NSFC)(62135012,62105107)+3 种基金Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(2021R01001)Guangdong Basic and Applied Basic Research Foundation(2021A 1515012215,2021B1515120057)Science and Technology Planning Project of Guangdong Province(2019A050510039)Fundamental Research Funds for the Central Universities(2021QNA5001).
文摘Multi-lane integrated transmitter chips are key components in future compact optical modules to realize high-speed optical interconnects.Thin-film lithium niobate(TFLN)photonics have emerged as a promising platform for achieving high-performance chip-scale optical systems.Combining a coarse wavelength-division multiplexing(CWDM)devices using fabrication-tolerant angled multimode interferometer structure and high-performance electro-optical modulators,we demonstrate monolithic on-chip four-channel CWDM transmitter on the TFLN platform for the first time.The four-channel CWDM transmitter enables high-speed transmissions of 100 Gb/s data rate per wavelength channel(i.e.,an aggregated date rate of 400 Gb/s).
基金Supported by the National Natural Science Foundation of China under Grant Nos 41474160 and 11304347
文摘An optimized transducer prototype with a sandwich structure vibrated longitudinally is proposed for a transmitter in acoustic logging, especially in acoustic logging while drilling, 5y taking account of drilling environments with high temperature and pressure, as well as strong collar drilling vibration during the drilling process. Aimed to improve the transmitting performance, numerical and experimental studies for the transducer optimization are conducted. The impact of location and length of the piezoelectric stack on resonance characteristics arid effective electromeehanical coupling coefficient is calculated and analyzed. Admittance and transmitting performance of the proposed transducer are measured in laboratory experiments, and the results are compared with simulated ones. It is shown that the newly proposed transducer has higher transmitting performance with lower resonance frequencies. This work provides theoretical and experimental bases for transducer designing and acoustic wave measurements in acoustic logging, especially in acoustic logging while drilling.
基金the Natural Science Foun-dation of Hubei Province under Grant 2019CFB593National Natural Science Foundation of China un-der Grant 61961016Starting Fund for Doc-toral Research in Hubei Minzu University under Grant MY2018B018.
文摘The traditional orthogonal frequency divi-sion multiplexing(OFDM)transmitter is implemented by inverse fast Fourier transform(IFFT),up-sampling and low pass shaping filter(LPSF),which occupy a large number of hardware resources and have long la-tency.To further meet the 5G and future 6G commu-nication requirements,this paper proposes a novel di-rect digital synthesis(DDS)based OFDM transmitter structure that can replace these modules.Due to the strong parallelism of the system structure,it is very suitable for implementation on field programable gate array(FPGA)platform.After making two special sim-plifications to the primary structure,the refined struc-ture becomes very simple compared with the tradi-tional structures.Most attractively,the proposed struc-ture has the following three advantages that i)the data transformation from frequency domain to time domain has zero latency,ii)the transformation length does not need to be an integer power of 2 and iii)the struc-ture does not even need to use any multiplier,thus leading to low implementation complexity and high speed.Comparative experiments are carried out on Intel FPGA platform which show that our DDS based structure can save more than half of the resources com-pared with the traditional structures and can provide the same bit error rate(BER)performance under the condition without using any LPSF.
基金Supported by the Hi-Tech Research and Development Program of China (No. 2009AAJ130)
文摘Non-collaborative radio transmitter recognition is a significant but challenging issue, since it is hard or costly to obtain labeled training data samples. In order to make effective use of the unlabeled samples which can be obtained much easier, a novel semi-supervised classification method named Elastic Sparsity Regularized Support Vector Machine (ESRSVM) is proposed for radio transmitter classification. ESRSVM first constructs an elastic-net graph over data samples to capture the robust and natural discriminating information and then incorporate the information into the manifold learning framework by an elastic sparsity regularization term. Experimental results on 10 GMSK modulated Automatic Identification System radios and 15 FM walkie-talkie radios show that ESRSVM achieves obviously better performance than KNN and SVM, which use only labeled samples for classification, and also outperforms semi-supervised classifier LapSVM based on manifold regularization.
文摘In this paper,we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory.In this work,to study the small range of temperature(40-100℃)although different temperature sensors can be used still,we have used here a K-type thermocouple as the measuring temperature sensor.The analog output voltage of thermocouple is amplified by instrumentation amplifier and the amplified signal is fed to the analog input of NI myRIO device which converts the analog input voltage signal as per the algorithm developed with virtual instrumentation based programming and provides the corresponding 4-20 mA output current signal in the analog output terminal of the device.Results show that input-output i.e.temperature-current relationship is linear.This low cost developed transmitter is very simple and it can be recommended for academic,scientific and industrial development of data acquisition systems,control and analysis of instruments.
文摘This paper presents the experimental results of a low-power RF transmitter for 2.4-GHz-band IEEE 802.15.4 standard in 0.18-μm CMOS technology. In order to make an adaptive RF transmitter, several factors must be considered. The most important factors are performances, power consumption, output power, noise factor, and cost. The RF transmitter comprises a quadrature passive mixer, and a power amplifier. The proposed RF transmitter consumes only 10.8-mW under a supply voltage of 1.8-V.
文摘This study compared three surgical techniques to implant acoustic transmitters in rainbow trout (</span><i><span style="font-family:Verdana;">Oncorhynchus mykiss</span></i><span style="font-family:Verdana;">): 1</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">)</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> acoustic transmitter insertion via a ventral incision closed with two sutures, 2</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">)</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> insertion via a ventral incision with no sutures, 3</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">)</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> insertion via a lateral incision with no sutures. A control group consisting of fish that were only anesthetized and handled was also included. Tag retention, wound healing, inflammation, growth, and survival were recorded over a 12</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">week period. Tag retention was significantly different among the treatments, at 100% in the unsutured ventral incision group, 89% in the lateral incision group, and 63% in the sutured ventral incision group. Surgical wounds in the unsutured treatment groups showed significantly less inflammation than the sutured treatment. Wound closure occurred significantly faster in the ventral incision groups compared to the lateral incision group. The results of this study show the utility of using unsutured surgical methods for implanting acoustic transmitters in rainbow trout.
文摘The present work deals with 12-bit Nyquist current-steering CMOS digital-to-analog converter (DAC) which is an essential part in baseband section of wireless transmitter circuits. Using oversampling ratio (OSR) for the proposed DAC leads to avoid use of an active analog reconstruction filter. The optimum segmentation (75%) has been used to get the best DNL and reduce glitch energy. This segmentation ratio guarantees the monotonicity. Higher performance is achieved using a new 3-D thermometer decoding method which reduces the area, power consumption and the number of control signals of the digital section. Using two digital channels in parallel, helps reach 1-GSample/s frequency. Simulation results show that the spurious- free-dynamic-range (SFDR) in Nyquist rate is better than 64 dB for sampling frequency up to 1-GSample/s. The analog voltage supply is 3.3 V while the digital part of the chip operates with only 2.4 V. Total power consumption in Nyquist rate measurement is 144.9 mW. The chip has been processed in a standard 0.35 μm CMOS technology. Active area of chip is 1.37 mm2.
文摘The implantation of acoustic transmitters into the peritoneal cavity of fish is typically performed by experienced surgeons. This study compared the effectiveness of an experienced and inexperienced surgeon performing two different types of transmitter insertion techniques on rainbow trout (<i>Oncorhynchus</i> <i>mykiss</i>). The methods used were either a traditional sutured ventral incision or a novel unsutured lateral incision. There was no significant difference in surgical duration, tag retention, or fish survival between the experienced and na<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">ï</span>ve surgeon. The time to complete surgical wound closure was not significantly different between the fish operated on by an experienced or na<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">ï</span>ve surgeon, and surgeon experience had no significant effect on the duration of inflammation. However, there were significant differences between the two surgical techniques, regardless of surgeon experience. The ventral incision with sutures method took approximately three times longer to complete than the lateral incision-only method. However, complete wound closure was significantly faster in the sutured ventral incision treatment compared to the unsutured lateral treatment. Post-surgery inflammation was over seven times longer in the fish with sutures compared to those only receiving a lateral incision. Tag retention was not significantly different between the two surgical methods. The results of this study indicate that the unsutured lateral surgical technique used in this experiment can be completed with minimal training and surgical experience in contrast to the standard technique requiring su<span>tures. These results also provide additional support to the use of sutureless</span> surgical techniques for acoustic transmitter implantation.
文摘In the present paper, the effects of moxibustion on the immune organs, on the multiplication reactivity of the splenic lymphocyte and the reactivity to the IL - 2, and on the transmitters in brain tissues of the mice with "yang deficiency" were studied. 30 mice were randomly divided into three groups: the normal group, the peng deficiency control group and the moxibustion treated group. Our study found out that in the mice of yang deficienly, the atrophy of the immunt organs was prevented, the reactivity of the splenocyte and the reactivity to IL - 2 were heightened, the amounts of the DA, NE and E in brain were increased significantly after moxibustion on the Point Shengshu. It can be held that moxibustion may protect the immune organs and regulate the immunity of the mouse with yang deficienly, and the effects may be contributed to the increase of the nervous transmitters in the brain.
文摘The present study aimed at the investigation of the changes of electrocardiogram (ECG) and monoamine transmitters in brainstem of rats with acute myocardial ischemia (AMl) with electroacupuncture (EA) at Neiguan (PC 6) and Jianshi (PC 5) treated by means of physiologic and histofluorescent and immunofluorescent methods. The results are as follows: 1. EA couId prevent ST segrnent and T wave from elevating during acute myocardial ischemia (P < 0. 05 ). 2. Monoamine-containing neurons with clear figure and bright fluoreasence, pre-and terminal axons were seen in Iocus coeruleus,lateral horn of splnal cord in two groups by the high specific sensitivity histofluorescence technique.The reaction of fluorescence was stronger in EA group than that in control one. The serotonin (5-HT) immunoreactive (ir) cells appeared in nucleus raphe (B 1, B 2). The 5-HT ir grains were more intense in EA group than that in control group. Tyrosine hydrotylase (TH) immunoreactive (ir) cell bodies were found within confines of catecholaminergic nuclei (A 1, A 2 ) of medulla. The immunofluorescence was weaker in EA group than that in control one. The results suggest that EA may regulate acute myocardial ischemia through brain stem.
基金supported by National Magnetic Confinement Fusion Science Program of China (No.2010GB110000)partly by Knowledge Innovation Program of the Chinese Academy of Sciences (No.Y05FCQ1126)partly supported by the Japan Society for the Promotion of Science-Chinese Academy of Sciences (JSPS-CAS) Core University Program on Plasma Physics and Nuclear Fusion
文摘An Ion Cyclotron Range of Frequency (ICRF) system with a radio frequency (RF) power of 4×1.5 MW was developed for the Experimental Advanced Superconducting Tokamak (EAST). High RF power transmitters were designed as a part of the research and development (R^D) for an ICRF system with long pulse operation at megawatt levels in a frequency range of 25 MHz to 70 MHz. Studies presented in this paper cover the following parts of the high power transmitter: the three staged high power amplifier, which is composed of a 5 kW wide- band solid state amplifier, a 100 kW tetrode drive stage amplifier and a 1.5 MW tetrode final stage amplifier, and the DC high voltage power supply (HVPS). Based on engineering design and static examinations, the RF transmitters were tested using a matched dummy load where an RF output power of 1.5 MW was achieved. The transmitters provide 6 MW RF power in primary phase and will reach a level up to 12 MW after a later upgrade. The transmitters performed successfully in stable operations in EAST and HT-7 devices. Up to 1.8 MW of RF power was injected into plasmas in EAST ICRF heating experiments during the 2010 autumn campaign and plasma performance was greatly improved.
文摘The structural composition, scheme selection and component design of a five-channel transmitter combiner for 800MHz trucking mobile communication system (TMC) is proposed. More attentions have been paid to the analysis and design of the high-Q microwave resonant cavity with accurate tuning structure. Also, a model transmitter combiner designed by the authors is proposed. Test results of the combiner are given. It has been proved that the technical specifications of the combiner have reached an advanced technical level compared with the products of the same kind imported from abroad.
基金This work was supported by National Key Research and Development Program of China(2018YFB2201101)the Strategic Priority Research Program of Chinese Academy of Sciences,Grant No.XDB43000000Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park No.Z201100004020004。
文摘In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical isolator.The whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output efficiency.After a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was obtained.The optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured.
文摘A 2.4 GHz high efficiency radio frequency (RF) transmitter for wireless body area network (WBAN) in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is proposed to achieve a high data rate with low power consumption. In conventional transmitters, the oscillator and power amplifier are turned off when the transmitter sends 0. The required time for turning oscillator ON/OFF is longer than the other blocks of the transmitter. In the proposed transmitter, the low power oscillator is on all the time while the power amplifier and modulator are turned off when"0"data is sent. The transmitter consumes 3.2 mW at 0.5 dBm output by 285 Mbps data rate and the energy consumption per transmitted bit with 0.5 dBm output power is 10 pJ/(bit-mW). The proposed transmitter was designed in 0.18 μm CMOS technology.