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Exploiting the Direct Link in IRS Assisted NOMA Networks with Hardware Impairments
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作者 Ziwei Liu Xinwei Yue +3 位作者 Shuo Chen Xuliang Liu Yafei Wang Wanwei Tang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期767-785,共19页
Hardware impairments(HI)are always present in low-cost wireless devices.This paper investigates the outage behaviors of intelligent reflecting surface(IRS)assisted non-orthogonal multiple access(NOMA)networks by takin... Hardware impairments(HI)are always present in low-cost wireless devices.This paper investigates the outage behaviors of intelligent reflecting surface(IRS)assisted non-orthogonal multiple access(NOMA)networks by taking into account the impact of HI.Specifically,we derive the approximate and asymptotic expressions of the outage probability for the IRS-NOMA-HI networks.Based on the asymptotic results,the diversity orders under perfect self-interference cancellation and imperfect self-interference cancellation scenarios are obtained to evaluate the performance of the considered network.In addition,the system throughput of IRS-NOMA-HI is discussed in delay-limited mode.The obtained results are provided to verify the accuracy of the theoretical analyses and reveal that:1)The outage performance and system throughput for IRS-NOMA-HI outperforms that of the IRS-assisted orthogonal multiple access-HI(IRS-OMA-HI)networks;2)The number of IRS elements,the pass loss factors,the Rician factors,and the value of HI are pivotal to enhancing the performance of IRS-NOMAHI networks;and 3)It is recommended that effective methods of reducing HI should be used to ensure system performance,in addition to self-interference cancellation techniques. 展开更多
关键词 hardware impairments imperfect SIC intelligent reflecting surface non-orthogonal multiple access outage probability
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System Outage Probability and Diversity Analysis of a SWIPT Based Two-Way DF Relay Network Under Transceiver Hardware Impairments
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作者 Guangyue Lu Zhipeng Liu +1 位作者 Yinghui Ye Xiaoli Chu 《China Communications》 SCIE CSCD 2023年第10期120-135,共16页
This paper investigates the system outage performance of a simultaneous wireless information and power transfer(SWIPT)based two-way decodeand-forward(DF)relay network,where potential hardware impairments(HIs)in all tr... This paper investigates the system outage performance of a simultaneous wireless information and power transfer(SWIPT)based two-way decodeand-forward(DF)relay network,where potential hardware impairments(HIs)in all transceivers are considered.After harvesting energy and decoding messages simultaneously via a power splitting scheme,the energy-limited relay node forwards the decoded information to both terminals.Each terminal combines the signals from the direct and relaying links via selection combining.We derive the system outage probability under independent but non-identically distributed Nakagami-m fading channels.It reveals an overall system ceiling(OSC)effect,i.e.,the system falls in outage if the target rate exceeds an OSC threshold that is determined by the levels of HIs.Furthermore,we derive the diversity gain of the considered network.The result reveals that when the transmission rate is below the OSC threshold,the achieved diversity gain equals the sum of the shape parameter of the direct link and the smaller shape parameter of the terminalto-relay links;otherwise,the diversity gain is zero.This is different from the amplify-and-forward(AF)strategy,under which the relaying links have no contribution to the diversity gain.Simulation results validate the analytical results and reveal that compared with the AF strategy,the SWIPT based two-way relaying links under the DF strategy are more robust to HIs and achieve a lower system outage probability. 展开更多
关键词 decode-and-forward relay diversity gain hardware impairments simultaneous wireless information and power transfer system outage probability
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Secrecy Outage Probability for Two-Way Integrated Satellite Unmanned Aerial Vehicle Relay Networks with Hardware Impairments
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作者 Xiaoting Ren Kefeng Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2515-2530,共16页
In this paper,we investigate the secrecy outage performance for the two-way integrated satellite unmanned aerial vehicle relay networks with hardware impairments.Particularly,the closed-form expression for the secrecy... In this paper,we investigate the secrecy outage performance for the two-way integrated satellite unmanned aerial vehicle relay networks with hardware impairments.Particularly,the closed-form expression for the secrecy outage probability is obtained.Moreover,to get more information on the secrecy outage probability in a high signalto-noise regime,the asymptotic analysis along with the secrecy diversity order and secrecy coding gain for the secrecy outage probability are also further obtained,which presents a fast method to evaluate the impact of system parameters and hardware impairments on the considered network.Finally,Monte Carlo simulation results are provided to show the efficiency of the theoretical analysis. 展开更多
关键词 Integrated satellite unmanned aerial vehicle relay networks two-way unmanned aerial vehicle relay hardware impairments secrecy outage probability(SOP) asymptotic SOP
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Spectral Efficiency of Superimposed Pilots in Cell-Free Massive MIMO Systems with Hardware Impairments 被引量:1
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作者 Yao Zhang Meng Zhou +2 位作者 Haitao Zhao Longxiang Yang Hongbo Zhu 《China Communications》 SCIE CSCD 2021年第6期146-161,共16页
In this paper,the spectral efficiency(SE)of an uplink hardware-constrained cell-free massive multi-input multi-output(MIMO)system with maximal ratio combining(MRC)receiver filters in the context of superimposed pilots... In this paper,the spectral efficiency(SE)of an uplink hardware-constrained cell-free massive multi-input multi-output(MIMO)system with maximal ratio combining(MRC)receiver filters in the context of superimposed pilots(SPs)is investigated.Tractable closed-form SE expressions for the considered system are derived,which share us with opportunities to explore the impacts of the hardware quality coefficient,the length of coherence interval,and the power balance factor between pilot and data signals.Numerical results indicate that the achievable SE deteriorates as the hardware quality decreases and is more susceptible to the hardware impairments at the user equipments(UEs).Besides,we observe that SPs outperform regular pilots(RPs)in terms of SE and this performance gain is heavily dependent on the values of power balance factor and coherence interval.However,the superiorities of SPs over RPs have vanished when severe hardware imperfections are considered. 展开更多
关键词 cell-free massive MIMO hardware impairments superimposed pilots spectral efficiency
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Performance analysis and low complexity receiver design for extra-large scale MIMO systems with residual hardware impairments
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作者 Lu Chang Fang Yuan +1 位作者 Qiu Ling Liang Xiaowen 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2023年第2期18-25,35,共9页
The research purpose of this paper is focused on investigating the performance of extra-large scale massive multiple-input multiple-output(XL-MIMO)systems with residual hardware impairments.The closed-form expression ... The research purpose of this paper is focused on investigating the performance of extra-large scale massive multiple-input multiple-output(XL-MIMO)systems with residual hardware impairments.The closed-form expression of the achievable rate under the match filter(MF)receiving strategy was derived and the influence of spatial non-stationarity and residual hardware impairments on the system performance was investigated.In order to maximize the signal-to-interference-plus-noise ratio(SINR)of the systems in the presence of hardware impairments,a hardware impairments-aware minimum mean squared error(HIA-MMSE)receiver was proposed.Furthermore,the stair Neumann series approximation was used to reduce the computational complexity of the HIA-MMSE receiver,which can avoid matrix inversion.Simulation results demonstrate the tightness of the derived analytical expressions and the effectiveness of the low complexity HIA-MMSE(LC-HIA-MMSE)receiver. 展开更多
关键词 extra-large scale massive multiple-input multiple-output(XL-MIMO) hardware impairments spatial non-stationarity linear receiver stair Neumann series
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Molecular biomarkers for vascular cognitive impairment and dementia:the current status and directions for the future
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作者 Satoshi Hosoki Perminder SSachdev 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2579-2580,共2页
Dementia is a syndrome with various underlying pathologies acting independently or in concert to cause cognitive dysfunction.The development of disease-specific treatments and targeted prevention strategies requires p... Dementia is a syndrome with various underlying pathologies acting independently or in concert to cause cognitive dysfunction.The development of disease-specific treatments and targeted prevention strategies requires precise clinical sub-typing via etiology and pathophysiological processes.Furthermore,recent research advances in biomarkers,especially for Alzheimer's disease(AD)diagnosis,have improved diagnostic precision for dementia. 展开更多
关键词 PREVENTION DIAGNOSIS impairment
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Factors Associated with Renal Impairment in Patients on Tenofovir for Chronic Hepatitis B in Yaoundé (Cameroon)
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作者 Antonin Wilson Ndjitoyap Ndam Sonia Charlsia Ewuo Shu +6 位作者 Mahamat Maimouna Winnie Bekolo Nga Isabelle Dang Babagna Paul Talla Mathurin Kowo Firmin Ankouane Andoulo Gloria Enow Ashuntantang 《Open Journal of Gastroenterology》 CAS 2024年第1期18-30,共13页
Background: Tenofovir (TFV) is widely used to treat patients with hepatitis B virus (HBV) infection. But kidney abnormalities are the main concern using this drug. Few studies have described the renal impairment due t... Background: Tenofovir (TFV) is widely used to treat patients with hepatitis B virus (HBV) infection. But kidney abnormalities are the main concern using this drug. Few studies have described the renal impairment due to the TFV in chronic hepatitis B (CHB) in Sub-Saharan Africa. The objective was to evaluate factors associated with renal impairment observed in patients on TFV for CHB. Method: It was a hospital based cross sectional prospective study carried out from June 2023 to July 2023 in Yaoundé (Cameroon) and included any patient treated with TFV for CHB during at least a period of 6 months. For each participant, we collected in the medical report socio-demographic data, clinical data, baseline creatinine, treatment information (type of TFV which was Disoproxil Fumarate (TDF) or Alafenamide (TAF), duration). Then, we collected blood samples to measure serum creatinine and phosphate levels and urine dipstick analysis. Factors associated with renal impairment were assessed with the Odds Ratio. A p value of Results: A total of 60 participants were included. The median age was 44 years [36-55] and median duration of TFV therapy was 17.5 months [11.7-25.7]. The prevalence of reduced eGFR (Conclusion: Kidney function was impaired in some patients receiving TFV for CHB. It should be monitored, particularly after 36 months and for those receiving TDF prodrug. 展开更多
关键词 Chronic Hepatitis B TENOFOVIR Factors Associated Renal impairment Cameroon
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Glyphosate as a direct or indirect activator of pro-inflammatory signaling and cognitive impairment
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作者 Yukitoshi Izumi Kazuko A.O'Dell Charles F.Zorumski 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2212-2218,共7页
Glyphosate-based herbicides are widely used around the world, making it likely that most humans have significant exposure. Because of habitual exposure, there are concerns about toxicity including neurotoxicity that c... Glyphosate-based herbicides are widely used around the world, making it likely that most humans have significant exposure. Because of habitual exposure, there are concerns about toxicity including neurotoxicity that could result in neurological, psychiatric, or cognitive impairment. We recently found that a single injection of glyphosate inhibits long-term potentiation, a cellular model of learning and memory, in rat hippocampal slices dissected 1 day after injection, indicating that glyphosate-based herbicides can alter cognitive function. Glyphosate-based herbicides could adversely affect cognitive function either indirectly and/or directly. Indirectly, glyphosate could affect gut microbiota, and if dysbiosis results in endotoxemia(leaky gut), infiltrated bacterial by-products such as lipopolysaccharides could activate pro-inflammatory cascades. Glyphosate can also directly trigger pro-inflammatory cascades. Indeed, we observed that acute glyphosate exposure inhibits long-term potentiation in rat hippocampal slices. Interestingly, direct inhibition of long-term potentiation by glyphosate appears to be similar to that of lipopolysaccharides. There are several possible measures to control dysbiosis and neuroinflammation caused by glyphosate. Dietary intake of polyphenols, such as quercetin, which overcome the inhibitory effect of glyphosate on long-term potentiation, could be one effective strategy. The aim of this narrative review is to discuss possible mechanisms underlying neurotoxicity following glyphosate exposure as a means to identify potential treatments. 展开更多
关键词 cognitive impairment GLYPHOSATE microglia NEUROINFLAMMATION ROUNDUP toll-like receptor 4 zinc chelation
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Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population
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作者 WANG Dan Dan WANG An Xin +3 位作者 ZHANG Xiao Li WEI Wen Bin WU Shou Ling ZHAO Xing Quan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第2期196-203,共8页
Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship betwee... Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular status.Methods We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or older.Logistic regression was used to analyze the relationship between retinal metrics and cognitive function.Subgroups stratified by different vascular statuses were also analyzed.Results RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel stenosis.The underlying small vessel change in RNFL and CI should be investigated in the future. 展开更多
关键词 Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality
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Garcinia Kola and Kolaviron Attenuates Bisphenol A-Induced Memory Impairment and Hippocampal Neuroinflammation in Male Wistar Rats
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作者 Nazizi Adamu Kayinu Bernard Omokheshi Adele Abayomi Oluwatosin Ige 《Journal of Biosciences and Medicines》 2024年第2期111-130,共20页
Bisphenol A (BPA), a toxicant which can leach into food from plastic containers, is reported to induce neurotoxicity among others via oxidative mechanisms. However, antioxidant compounds have been suggested to mitigat... Bisphenol A (BPA), a toxicant which can leach into food from plastic containers, is reported to induce neurotoxicity among others via oxidative mechanisms. However, antioxidant compounds have been suggested to mitigate BPA-induced toxicities. Garcinia kola (GK) and its bioactive compound, kolaviron, are well-established natural antioxidants, which can exert protective effects against BPA-induced toxicities. This study was designed to investigate the likely mitigating effect of GK and kolaviron on BPA-induced memory impairment and hippocampal neuroinflammation in male Wistar rats. Thirty-five rats were equally grouped and treated as follows: I and II received distilled water and corn oil, respectively at 0.2 mL, while III - VII received BPA (50 mg/kg), BPA + GK (200 mg/kg), BPA + kolaviron (200 mg/kg), GK and kolaviron, respectively for 28 days p.o. Thereafter, behavioral studies were done using the Novel Object Recognition and Y maze tests. Subsequently under anaesthesia, the hippocampus in each animal was dissected out, homogenized and analysed for malondialdehyde, superoxide dismutase, catalase, reduced glutathione, glutathione transferase, nitrites, interleukin-6, tumour necrosis factor-α, acetylcholinesterase, glutamate acid decarboxylase, and arginase activity. Data were analyzed by ANOVA and Tukey Post-hoc test at p p Garcinia kola and Kolaviron mitigate bisphenol A-induced memory impairment and neuroinflammation via antioxidant potentiation and neurotransmitter balance. 展开更多
关键词 Bisphenol A Memory impairment NEUROINFLAMMATION NEUROPROTECTION Garcinia Kola KOLAVIRON ANTIOXIDANT
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Prevalence of visual impairment and estimation of refractive errors among school children in Kakamega,Kenya
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作者 Isabel Signes-Soler Alfred Ragot +2 位作者 Sheilah Nangena Andrew Wekesa Raúl Montalbán Llamusí 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期932-939,共8页
AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was... AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry students as a community service.METHODS:The study was cross-sectional.Totally 3343 participants were included in the study.The initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D lens.The inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVA<0.6 decimal(0.20 logMAR)and/or a VA with+2.00 D≥0.8 decimal(0.96 logMAR).RESULTS:The sample had a mean age of 10.92±2.13y(range 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to 14y.Among the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye examination.The estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total sample.While around 0.18%of the total sample had hyperopia value exceeding+1.75 D.Refractive astigmatism(cil<-0.75 D)was found in 0.21%(7/3343)of the children.The VI prevalence was 1.26%of the total sample.Among our cases of VI,76.2%could be attributed to uncorrected refractive error.Amblyopia was detected in 0.66%(22/3343)of the screened children.There was no statistically significant correlation observed between age or gender and refractive values.CONCLUSION:The primary cause of VI is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error observed.These findings underscore the significance of early identification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI. 展开更多
关键词 visual impairment refractive errors MYOPIA AMBLYOPIA sustainable development goals
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Risk factors for cognitive impairment in patients with chronic kidney disease
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作者 Xiao-Hui Wang Yong He +3 位作者 Huan Zhou Ting Xiao Ran Du Xin Zhang 《World Journal of Psychiatry》 SCIE 2024年第2期308-314,共7页
BACKGROUND Chronic kidney disease(CKD)patients have been found to be at risk of concurrent cognitive dysfunction in previous studies,which has now become an important public health issue of widespread concern.AIM To i... BACKGROUND Chronic kidney disease(CKD)patients have been found to be at risk of concurrent cognitive dysfunction in previous studies,which has now become an important public health issue of widespread concern.AIM To investigate the risk factors for concurrent cognitive dysfunction in patients with CKD.METHODS This is a prospective cohort study conducted among patients with CKD between October 2021 and March 2023.A questionnaire was formulated by literature review and expert consultation and included questions about age,sex,education level,per capita monthly household income,marital status,living condition,payment method,and hypertension.RESULTS Logistic regression analysis showed that patients aged 60-79 years[odds ratio(OR)=1.561,P=0.015]and≥80 years(OR=1.760,P=0.013),participants with middle to high school education(OR=0.820,P=0.027),divorced or widowed individuals(OR=1.37,P=0.032),self-funded patients(OR=2.368,P=0.008),and patients with hypertension(OR=2.011,P=0.041)had a higher risk of cognitive impairment.The risk of cognitive impairment was lower for those with a college degree(OR=0.435,P=0.034)and married individuals.CONCLUSION The risk factors affecting cognitive dysfunction are age,60-79 years and≥80 years;education,primary school education or less;marital status,divorced or widowed;payment method,selffunded;hypertension;and CKD. 展开更多
关键词 Cognitive impairment Cognitive dysfunction Chronic kidney disease
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Novel insights into immune-related genes associated with type 2 diabetes mellitus-related cognitive impairment
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作者 Jing Gao Ying Zou +2 位作者 Xiao-Yu Lv Li Chen Xin-Guo Hou 《World Journal of Diabetes》 SCIE 2024年第4期735-757,共23页
BACKGROUND The cognitive impairment in type 2 diabetes mellitus(T2DM)is a multifaceted and advancing state that requires further exploration to fully comprehend.Neu-roinflammation is considered to be one of the main m... BACKGROUND The cognitive impairment in type 2 diabetes mellitus(T2DM)is a multifaceted and advancing state that requires further exploration to fully comprehend.Neu-roinflammation is considered to be one of the main mechanisms and the immune system has played a vital role in the progression of the disease.AIM To identify and validate the immune-related genes in the hippocampus associated with T2DM-related cognitive impairment.METHODS To identify differentially expressed genes(DEGs)between T2DM and controls,we used data from the Gene Expression Omnibus database GSE125387.To identify T2DM module genes,we used Weighted Gene Co-Expression Network Analysis.All the genes were subject to Gene Set Enrichment Analysis.Protein-protein interaction network construction and machine learning were utilized to identify three hub genes.Immune cell infiltration analysis was performed.The three hub genes were validated in GSE152539 via receiver operating characteristic curve analysis.Validation experiments including reverse transcription quantitative real-time PCR,Western blotting and immunohistochemistry were conducted both in vivo and in vitro.To identify potential drugs associated with hub genes,we used the Comparative Toxicogenomics Database(CTD).RESULTS A total of 576 DEGs were identified using GSE125387.By taking the intersection of DEGs,T2DM module genes,and immune-related genes,a total of 59 genes associated with the immune system were identified.Afterward,machine learning was utilized to identify three hub genes(H2-T24,Rac3,and Tfrc).The hub genes were associated with a variety of immune cells.The three hub genes were validated in GSE152539.Validation experiments were conducted at the mRNA and protein levels both in vivo and in vitro,consistent with the bioinformatics analysis.Additionally,11 potential drugs associated with RAC3 and TFRC were identified based on the CTD.CONCLUSION Immune-related genes that differ in expression in the hippocampus are closely linked to microglia.We validated the expression of three hub genes both in vivo and in vitro,consistent with our bioinformatics results.We discovered 11 compounds associated with RAC3 and TFRC.These findings suggest that they are co-regulatory molecules of immunometabolism in diabetic cognitive impairment. 展开更多
关键词 Bioinformatics analysis Type 2 diabetes mellitus Cognitive impairment HIPPOCAMPUS IMMUNE MICROGLIA
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Estimating High-Order Functional Connectivity Networks for Mild Cognitive Impairment Identification Based on Topological Structure
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作者 Guangyi Zhang Kunpeng Zhang Mengxue Pang 《Journal of Computer and Communications》 2024年第3期14-31,共18页
Functional connectivity networks (FCNs) are important in the diagnosis of neurological diseases and the understanding of brain tissue patterns. Recently, many methods, such as Pearson’s correlation (PC), Sparse repre... Functional connectivity networks (FCNs) are important in the diagnosis of neurological diseases and the understanding of brain tissue patterns. Recently, many methods, such as Pearson’s correlation (PC), Sparse representation (SR), and Sparse low-rank representation have been proposed to estimate FCNs. Despite their popularity, they only capture the low-order connections of the brain regions, failing to encode more complex relationships (i.e. , high-order relationships). Although researchers have proposed high-order methods, like PC + PC and SR + SR, aiming to build FCNs that can reflect more real state of the brain. However, such methods only consider the relationships between brain regions during the FCN construction process, neglecting the potential shared topological structure information between FCNs of different subjects. In addition, the low-order relationships are always neglected during the construction of high-order FCNs. To address these issues, in this paper we proposed a novel method, namely Ho-FCN<sub>Tops</sub>, towards estimating high-order FCNs based on brain topological structure. Specifically, inspired by the Group-constrained sparse representation (GSR), we first introduced a prior assumption that all subjects share the same topological structure in the construction of the low-order FCNs. Subsequently, we employed the Correlation-reserved embedding (COPE) to eliminate noise and redundancy from the low-order FCNs. Meanwhile, we retained the original low-order relationships during the embedding process to obtain new node representations. Finally, we utilized the SR method on the obtained new node representations to construct the Ho-FCN<sub>Tops</sub> required for disease identification. To validate the effectiveness of the proposed method, experiments were conducted on 137 subjects from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database to identify Mild Cognitive Impairment (MCI) patients from the normal controls. The experimental results demonstrate superior performance compared to baseline methods. 展开更多
关键词 Ho-FCN Sparse Representation Mild Cognitive impairment Disease Recognition
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Cognitive impairment in cerebral small vessel disease induced by hypertension
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作者 Weipeng Wei Denglei Ma +1 位作者 Lin Li Lan Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1454-1462,共9页
Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension a... Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular disease.Howeve r,the causal relationship between hypertension and cerebral small vessel disease remains unclear.Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease.Chronic hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and stroke.Hypertension is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of hypertension.This review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive ability.We also discuss drugs to treat cerebral small vessel disease and cognitive impairment. 展开更多
关键词 blood-brain barrier cerebral small vessel disease cognitive impairment DEMENTIA endothelial dysfunction enlarged perivascular space HYPERTENSION lacunar infarction NEUROINFLAMMATION TREATMENT white matter high signal intensity
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A High Efficiency Hardware Implementation of S-Boxes Based on Composite Field for Advanced Encryption Standard
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作者 Yawen Wang Sini Bin +1 位作者 Shikai Zhu Xiaoting Hu 《Journal of Computer and Communications》 2024年第4期228-246,共19页
The SubBytes (S-box) transformation is the most crucial operation in the AES algorithm, significantly impacting the implementation performance of AES chips. To design a high-performance S-box, a segmented optimization... The SubBytes (S-box) transformation is the most crucial operation in the AES algorithm, significantly impacting the implementation performance of AES chips. To design a high-performance S-box, a segmented optimization implementation of the S-box is proposed based on the composite field inverse operation in this paper. This proposed S-box implementation is modeled using Verilog language and synthesized using Design Complier software under the premise of ensuring the correctness of the simulation result. The synthesis results show that, compared to several current S-box implementation schemes, the proposed implementation of the S-box significantly reduces the area overhead and critical path delay, then gets higher hardware efficiency. This provides strong support for realizing efficient and compact S-box ASIC designs. 展开更多
关键词 Advanced Encryption Standard (AES) S-BOX Tower Field hardware Implementation Application Specific Integration Circuit (ASIC)
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Multipair two-way massive MIMO AF relaying with ZFR/ZFT and hardware impairments over high-altitude platforms 被引量:1
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作者 SUN Xiaoli XU Kui +1 位作者 XU Youyun MA Wenfeng 《Journal of Communications and Information Networks》 2016年第3期105-114,共10页
HAPs(High-Altitude Platforms)are one of the most promising alternative infrastructures for providing wireless communications to overcome the shortcomings of terrestrial-tower-based and satellite systems.This paper inv... HAPs(High-Altitude Platforms)are one of the most promising alternative infrastructures for providing wireless communications to overcome the shortcomings of terrestrial-tower-based and satellite systems.This paper investigates a multipair two-way MM-AF(Massive MIMO Amplify-and-Forward)relay system over HAPs,where multiple user pairs exchange information within a pair through a relay with a very large number of antennas,and a HAP channel is modeled to follow a Rician fading distribution because of the presence of a line-of-sight path.First,the effect of hardware impairments on a multipair two-way MM-AF system is taken into consideration and is modeled using transmit and receive distortion noises.Then,ZFR/ZFT(Zero-Forcing Reception/Zero-Forcing Transmission)processing matrices of HDR(Half-Duplex Relaying)and FDR(Full-Duplex Relaying)with imperfect channel state information are presented.Finally,the asymptotic expressions of an end-to-end SINR are derived.Theoretical analyses and simulation results show that when the number of relay antennas grows very large,the SE(Spectral Efficiency)of an MM-AF relay system is limited by hardware impairments at the users instead of those at the relay,or by other types of interference.Thus,the quality of the hardware at a relay can be decreased without significantly degrading performance. 展开更多
关键词 massive MIMO HALF-DUPLEX full-duplex Rician fading channels hardware impairments
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Mechanism of Learning and Memory Impairment in Rats Exposed to Arsenic and/or Fluoride Based on Microbiome and Metabolome 被引量:2
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作者 ZHANG Xiao Li YU Sheng Nan +12 位作者 QU Ruo Di ZHAO Qiu Yi PAN Wei Zhe CHEN Xu Shen ZHANG Qian LIU Yan LI Jia GAO Yi LYU Yi YAN Xiao Yan LI Ben REN Xue Feng QIU Yu Lan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第3期253-268,共16页
Objective Arsenic(As) and fluoride(F) are two of the most common elements contaminating groundwater resources. A growing number of studies have found that As and F can cause neurotoxicity in infants and children, lead... Objective Arsenic(As) and fluoride(F) are two of the most common elements contaminating groundwater resources. A growing number of studies have found that As and F can cause neurotoxicity in infants and children, leading to cognitive, learning, and memory impairments. However, early biomarkers of learning and memory impairment induced by As and/or F remain unclear. In the present study, the mechanisms by which As and/or F cause learning memory impairment are explored at the multi-omics level(microbiome and metabolome).Methods We stablished an SD rats model exposed to arsenic and/or fluoride from intrauterine to adult period.Results Arsenic and/fluoride exposed groups showed reduced neurobehavioral performance and lesions in the hippocampal CA1 region. 16S rRNA gene sequencing revealed that As and/or F exposure significantly altered the composition and diversity of the gut microbiome, featuring the Lachnospiraceae_NK4A136_group, Ruminococcus_1, Prevotellaceae_NK3B31_group, [Eubacterium]_xylanophilum_group. Metabolome analysis showed that As and/or F-induced learning and memory impairment may be related to tryptophan, lipoic acid, glutamate, gamma-aminobutyric acidergic(GABAergic) synapse, and arachidonic acid(AA) metabolism. The gut microbiota, metabolites, and learning memory indicators were significantly correlated.Conclusion Learning memory impairment triggered by As and/or F exposure may be mediated by different gut microbes and their associated metabolites. 展开更多
关键词 ARSENIC FLUORIDE Learning and memory impairment MICROBIOME METABOLOME
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BI-D1870 Causes the Rats’ Learning and Memory Acquisition Ability Impairment 被引量:1
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作者 Chaojie Zhang Ke He +1 位作者 Caixia Li Yazhen Shang 《Journal of Biosciences and Medicines》 CAS 2023年第1期82-97,共16页
Aim: To observe the rats’ learning and memory acquisition ability disturbance induced by BI-D1870. Methods: Male SD rats were randomly divided into control group, solvent control group and BI-D1870 group. The rats in... Aim: To observe the rats’ learning and memory acquisition ability disturbance induced by BI-D1870. Methods: Male SD rats were randomly divided into control group, solvent control group and BI-D1870 group. The rats in the control group were intraperitoneally injected with saline, while those in the solvent control group were intraperitoneally injected with DMSO + sulfobutyl-β-cyclodextrin solvent, and those in the BI-D1870 group were intraperitoneally injected with BI-D1870. All the rats’ appearance and behavior were daily observed, and body weight was recorded on the day 15, 30, 45, 60, 75 and 82 of BI-D1870 injected. Morris water maze was used to screen the rats’ learning and memory acquisition ability on the day 22 - 25, 52 - 55, and 82 - 85 of training by BI-D1870 treated. The successful rates of the rats’ memory impairment were respectively calculated for three times screening. Results: During the whole experiment, there was no obvious difference in appearance and fur color in all rats. The rats’ agitation began to appear on the day 10th of BI-D1870 given. The agitation rats’ number and rats’ body weight gradually increased along with BI-D1870 treated (P P Conclusion: Intraperitoneal injection of BI-D1870 can induce the rats’ learning and memory acquisition ability disorder. 展开更多
关键词 BI-D1870 Learning and Memory Acquisition impairment Morris Water Maze RSK Inhibitor
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β2-Microglobulin exacerbates neuroinflammation,brain damage,and cognitive impairment after stroke in rats 被引量:3
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作者 Feng Chen Jing Liu +5 位作者 Fa-Qiang Li Shuai-Shuai Wang Yan-Yan Zhang Yun-Yun Lu Fang-Fang Hu Rui-Qin Yao 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期603-608,共6页
β2-Microglobulin(β2M),a component of the major histocompatibility complex class I molecule,is associated with aging-related cognitive impairment and Alzheimer’s disease.Although upregulation ofβ2M is considered to... β2-Microglobulin(β2M),a component of the major histocompatibility complex class I molecule,is associated with aging-related cognitive impairment and Alzheimer’s disease.Although upregulation ofβ2M is considered to be highly related to ischemic stroke,the specific role and underlying mechanistic action ofβ2M are poorly understood.In this study,we established a rat model of focal cerebral ischemia by occlusion of the middle cerebral artery.We found thatβ2M levels in the cerebral spinal fluid,serum,and brain tissue were significantly increased in the acute period but gradually decreased during the recovery period.RNA interference was used to inhibitβ2M expression in the acute period of cerebral stroke.Tissue staining with 2,3,5-triphenyltetrazolium chloride and evaluation of cognitive function using the Morris water maze test demonstrated that decreasedβ2M expression in the ischemic penumbra reduced infarct volume and alleviated cognitive deficits,respectively.Notably,glial cell,caspase-1(p20),and Nod-like receptor pyrin domain containing 3(NLRP3)inflammasome activation as well as production of the inflammatory cytokines interleukin-1β,interleukin-6,and tumor necrosis factor-αwere also effectively inhibited byβ2M silencing.These findings suggest thatβ2M participates in brain injury and cognitive impairment in a rat model of ischemic stroke through activation of neuroinflammation associated with the NLRP3 inflammasome. 展开更多
关键词 cognitive impairment cognitive improvement glial activation infarct volume ISCHEMIA middle cerebral artery occlusion NEUROINFLAMMATION NLRP3 inflammasome STROKE β2 microglobulin
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