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Heat stroke alters hippocampal and cerebellar transmitter metabonomics
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作者 Guoxin He Ancong Xu +2 位作者 Xichong Yu Fan Huang Lei Su 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第4期287-293,共7页
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
关键词 Heat stroke transmitters Rat HIPPOCAMPUS CEREBELLUM METABONOMICS
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Glass-Ceramics with High Strength and High Transmittance Obtained by Multi-Factor Controlling
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作者 胡云坤 RAO Yu +4 位作者 WANG Mingzhong XU Yinsheng XIA Mengling TAO Haizheng 陆平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期551-560,共10页
The presence of Li_(2)Si_(2)O_(5) and LiAlSi_(4)O_(10) could effectively improve the elastic modulus and transmittance of lithium disilicate(LD)glass-ceramics.Through synergistically modulation of the crystal content ... The presence of Li_(2)Si_(2)O_(5) and LiAlSi_(4)O_(10) could effectively improve the elastic modulus and transmittance of lithium disilicate(LD)glass-ceramics.Through synergistically modulation of the crystal content and grain size,we obtained high strength and high transmittance of LD glass-ceramics.The optimal sample had a high transmittance of 90.3%,the hardness was 7.72 GPa,the fracture toughness was 1.07 MPa·m^(1/2),and the elastic modulus was 103.1 GPa. 展开更多
关键词 lithium disilicate GLASS-CERAMICS transmittANCE mechanical properties
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A novel multi-channel porous structure facilitating mass transport towards highly efficient alkaline water electrolysis
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作者 Xinge Jiang Vasileios Kyriakou +6 位作者 Chen Song Xianbin Wang Sophie Costil Chunming Deng Taikai Liu Tao Jiang Hanlin Liao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期511-518,I0013,共9页
An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport mechanisms.This effect becomes even more pronounced w... An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport mechanisms.This effect becomes even more pronounced when aiming to achieve elevated current densities.Herein,we employed a rapid and scalable laser texturing process to craft novel multi-channel porous electrodes.Particularly,the obtained electrodes exhibit the lowest Tafel slope of 79 mV dec^(-1)(HER)and 49 mV dec^(-1)(OER).As anticipated,the alkaline electrolyzer(AEL)cell incorporating multi-channel porous electrodes(NP-LT30)exhibited a remarkable improvement in cell efficiency,with voltage drops(from 2.28 to 1.97 V)exceeding 300 mV under 1 A cm^(-1),compared to conventional perforated Ni plate electrodes.This enhancement mainly stemmed from the employed multi-channel porous structure,facilitating mass transport and bubble dynamics through an innovative convection mode,surpassing the traditional convection mode.Furthermore,the NP-LT30-based AEL cell demonstrated exceptional durability for 300 h under 1.0 A cm^(-2).This study underscores the capability of the novel multi-channel porous electrodes to expedite mass transport in practical AWE applications. 展开更多
关键词 Alkaline water electrolysis Mass transport Bubble dynamics Innovative convection mode multi-channel porous structure
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Design of Cold-Junction Compensation and Disconnection Detection Circuits of Various Thermocouples and Implementation of Multi-Channel Interfaces Using Them-A Secondary Publication
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作者 Hyeong-Woo Cha 《Journal of Electronic Research and Application》 2024年第1期93-105,共13页
Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC... Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain. 展开更多
关键词 R-type thermocouple(TC) Cold-junction compensation(CJC) TC disconnection detection multi-channel interface circuit Sensor interface
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SEMI-SUPERVISED RADIO TRANSMITTER CLASSIFICATION BASED ON ELASTIC SPARSITY REGULARIZED SVM 被引量:2
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作者 Hu Guyu Gong Yong +2 位作者 Chen Yande Pan Zhisong Deng Zhantao 《Journal of Electronics(China)》 2012年第6期501-508,共8页
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
关键词 Radio transmitter recognition Cyclic spectrum density Semi-supervised classification Elastic Sparsity Regularized Support Vector Machine (ESRSVM)
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Dopamine: an immune transmitter 被引量:5
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作者 Sarah Thomas Broome Krystal Louangaphay +3 位作者 Kevin AKeay Gian Marco Leggio Giuseppe Musumeci Alessandro Castorina 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第12期2173-2185,共13页
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
关键词 ASTROCYTE autoimmune disease DOPAMINE dopamine receptors D3R immune transmitter MICROGLIA multiple sclerosis NEUROINFLAMMATION Parkinson’s disease
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A 2.4-GHz-Low-Power CMOS RF Transmitter for IEEE 802.15.4 Standard 被引量:2
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作者 Mohen Nasri Amina Msolli +1 位作者 Abdelhamid Helali Hassen Maaref 《Wireless Sensor Network》 2012年第6期173-176,共4页
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
关键词 IEEE 802.15.4 transmitter CMOS LOW COST LOW Power Wireless Sensor Network
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Novel DDS Based OFDM Transmitter Structure without IFFT and Interpolation Filter 被引量:2
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作者 Sanjun Liu Guangming Gan 《China Communications》 SCIE CSCD 2021年第12期219-229,共11页
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
关键词 OFDM transmitter direct digital synthe-sis(DDS) fast Fourier transform(FFT)
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Optimization Design for the Sandwich Piezoelectric Transmitters in Acoustic Logging 被引量:1
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作者 魏倩 王秀明 +1 位作者 车承轩 丛健生 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期102-104,共3页
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
关键词 of on in Optimization Design for the Sandwich Piezoelectric transmitters in Acoustic Logging IS for
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Assessment of a Novel Surgical Technique for Acoustic Transmitter Insertion 被引量:1
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作者 Ashley N. Kelican Nathan Huysman +2 位作者 Lauren Van Ryssleberge Jill M. Voorhees Michael E. Barnes 《Open Journal of Veterinary Medicine》 2021年第7期247-257,共11页
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
关键词 Rainbow Trout Acoustic transmitter SURGERY Unsutured
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Novel Surgical Technique for Acoustic Transmitter Insertion in Rainbow Trout Reduces the Need for Surgical Training 被引量:1
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作者 Nathan Huysman Ashley Kelican +3 位作者 Lauren Van Rysselberge Jeremy Kientz Jill M. Voorhees Michael E. Barnes 《Advances in Bioscience and Biotechnology》 2021年第9期275-285,共11页
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;">&#239;</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;">&#239;</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
关键词 SURGERY Acoustic transmitter Rainbow Trout Oncorhynchus mykiss
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A 12-Bit 1-Gsample/s Nyquist Current-Steering DAC in 0.35 µm CMOS for Wireless Transmitter 被引量:1
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作者 Peiman Aliparast Hossein B. Bahar +2 位作者 Ziaadin D. Koozehkanani Jafar Sobhi Gader Karimian 《Circuits and Systems》 2011年第2期74-84,共11页
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
关键词 Wireless transmitter 3-D THERMOMETER DECODING Current STEERING DAC WLAN Integrated Circuits CMOS
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EFFECTS OF MOXIBUSTION ON THE IMMUNITY AND THE CENTRAL NERVOUS TRANSMITTERS IN MICE WITH YANG DEFICIENCY
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作者 宋小鸽 唐照亮 +4 位作者 侯正明 陈全珠 袁静 章复清 朱舜丽 《World Journal of Acupuncture-Moxibustion》 1999年第4期47-50,共4页
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
关键词 IMMUNITY CENTRAL nervous transmitter MOXIBUSTION Yang DEFICIENCY
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INFLUENCE OF EA ON ELECTROCARDIOGRAM AND MONOAMINE TRANSMITTER AND c-Fos OF BRAIN STEM OF ACUTE MYOCARDIAL ISCHEMIA IN RATS
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作者 罗明富 高永辉 +3 位作者 王志英 王平 刘俊岭 曹庆淑 《World Journal of Acupuncture-Moxibustion》 1997年第3期50-53,共4页
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
关键词 Acute ISCHEMIC MYOCARDIUM ECG C-FOS MONOAMINE transmitter
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High Power RF Transmitters for ICRF Applications on EAST
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作者 毛玉周 袁帅 +9 位作者 赵燕平 张新军 陈根 R.KUMAZAWA 程艳 王磊 琚松青 邓旭 秦成明 杨磊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第3期261-265,共5页
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
关键词 power amplifier RF transmitter ICRF system EAST
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Outage performance of cognitive multisource multidestination relay networks with imperfect channel state information and interference from primary transmitter
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作者 刘帅 Sun Dechun +3 位作者 Liu Zujun Yi Kechu Yang Hong Wang Kan 《High Technology Letters》 EI CAS 2019年第4期369-377,共9页
Given imperfect channel state information(CSI)and considering the interference from the primary transmitter,an underlay cognitive multisource multidestination relay network is proposed.A closed-form exact outage proba... Given imperfect channel state information(CSI)and considering the interference from the primary transmitter,an underlay cognitive multisource multidestination relay network is proposed.A closed-form exact outage probability and asymptotic outage probability are derived for the secondary system of the network.The results show that the outage probability is influenced by the source and destination number,the CSI imperfection as well as the interference from the primary transmitter,while the diversity order is independent of the CSI imperfection and the interference from the primary transmitter,yet it is equal to the minimum of the source and destination number.Moreover,extensive simulations are conducted with different system parameters to verify the theoretical analysis. 展开更多
关键词 OUTAGE performance COGNITIVE network channel state information(CSI) primary transmitter
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A LOW EVM ZERO-IF RF TRANSMITTER FOR COGNITIVE RADIO APPLICATION
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作者 Zhang Xiaodong Zhu Xiaowei Liu Jing You Changjiang 《Journal of Electronics(China)》 2010年第5期723-727,共5页
A zero-IF transmitter for Cognitive Radio(CR) application is presented.To effectively reduce the interference between Power Amplifier(PA) and Voltage Controlled Oscillator(VCO),two VCOs are adopted,one is 450 MHz and ... A zero-IF transmitter for Cognitive Radio(CR) application is presented.To effectively reduce the interference between Power Amplifier(PA) and Voltage Controlled Oscillator(VCO),two VCOs are adopted,one is 450 MHz and the other is from 1148 MHz to 1252 MHz with an 8 MHz step,so the frequency of them are different from the operational frequency of PA.The Local Oscillator(LO) of the modulator generated by mixing the signals of the two VCOs has a low phase noise of-82 dBc/Hz with an offset of 1 kHz.The measurement result of the transmitter shows that the Adjacent Channel Power Ratio(ACPR) is less than-47.5 dBc at 27 dBm output,and the Error Vector Magnitude(EVM) is less than 1.7%. 展开更多
关键词 Cognitive Radio (CR) ZERO-IF transmitter Error Vector Magnitude (EVM)
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Receiver Power Allocation and Transmitter Power Control Analysis for Multiple-Receiver Wireless Power Transfer Systems
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作者 Zhi-Hao Guo Shi-Er Dong 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第4期291-299,共9页
As different power has its own receivers,this paper analyzes and designs a multiple-receiver wireless power transfer(WPT)system systematically.The equivalent circuit model of the system is established to analyze the k... As different power has its own receivers,this paper analyzes and designs a multiple-receiver wireless power transfer(WPT)system systematically.The equivalent circuit model of the system is established to analyze the key parameters including transmitter power,receiver power,transmission efficiency,and each receiver power allocation.A control circuit is proposed to achieve the maximum transmission efficiency and transmitter power control and arbitrary receiver power allocation ratios for different receivers.Through the proposed control circuit,receivers with different loads can allocate appropriate power according to its power demand,the transmitter power and system efficiency do not vary with the change of the number of receivers.Finally,this control circuit is validated using a 130-kHz WPT system with three receivers whose power received is 3:10:12,and the overall system efficiency can reach as high as 55.5%. 展开更多
关键词 Multiple-receiver receiver power allocation transmitter power control wireless power transfer(WPT).
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Improved time-interleaved error feedback delta sigma modulator for digital transmitter application
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作者 花再军 Fan Xiangning Liao Yilong 《High Technology Letters》 EI CAS 2018年第4期337-342,共6页
Time-interleaved structure can promote the equivalent processing speed of a digital signal processing system. An improved time-interleaved error feedback delta sigma modulator( TI-EF-DSM)for digital transmitter applic... Time-interleaved structure can promote the equivalent processing speed of a digital signal processing system. An improved time-interleaved error feedback delta sigma modulator( TI-EF-DSM)for digital transmitter application is presented in this paper. Two TI-EF-DSMs are compared,one is a conventional directly implemented and the other is the improved. The processing speed of the proposed two-channel improved time-interleaved error feedback delta sigma modulator( ITI-EF-DSM) is higher than the conventional directly implemented TI-EF-DSM for shortened critical path. A digital transmitter based on the ITI-EF-DSM is implemented on field progrmmable gate array( FPGA). The long term evolution( LTE) signals with different bandwidths of 5 MHz,10 MHz and 20 MHz are used as the signal source to evaluate the transmitter. The achieved SNR is 41 dB for the 20 MHz LTE signal with the processing clock of only 184 MHz. 展开更多
关键词 time-interleaved error feedback delta SIGMA modulator(EF-DSM) digital transmitter long term evolution(LTE)
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RESEARCH ON TECHNOLOGY OF CONTROLLED SOURCE RADIO MAGNETOTELLURIC SYSTEM'S TRANSMITTER
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作者 Xu Yongfeng Liu Lihua +2 位作者 Wu Kai Geng Zhi Fang Guangyou 《Journal of Electronics(China)》 2014年第6期609-618,共10页
The basic theory and principle of the artificial Controlled Source Radio Magneto Telluric(CSRMT) method is studied and a novel CSRMT transmitter in kH z frequency band is designed. The specific circuit and measured re... The basic theory and principle of the artificial Controlled Source Radio Magneto Telluric(CSRMT) method is studied and a novel CSRMT transmitter in kH z frequency band is designed. The specific circuit and measured results of some key modules in transmitter are presented, and some outdoor experimental tests have been carried out, which shows that the completed prototype of transmitter can generate a continuous sine current with frequency up to 35.33 k Hz, peak-to-peak amplitude up to 40 A, and realize a reliable transmitting mode with multi-frequency and high-current. The transmitter has a wide operating band, large magnetic moment and high waveform fidelity, and can meet the requirements of shallow geological exploration with high-resolution. 展开更多
关键词 Controlled Source Radio Magneto Telluric(CSRMT) transmitter technology Sine wave source Large current BROADBAND
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