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AB013.The effects of monocular deprivation on the Pulfrich phenomenon
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作者 Sasha Novozhilova Alexandre Reynaud Robert F.Hess 《Annals of Eye Science》 2019年第1期188-188,共1页
Background:Short term monocular deprivation allows for the modulation of ocular dominance,such that the previously deprived eye contribution will increase,while that of non-deprived eye will decrease.This study examin... Background:Short term monocular deprivation allows for the modulation of ocular dominance,such that the previously deprived eye contribution will increase,while that of non-deprived eye will decrease.This study examines the effects of short monocular occlusion on the Pulfrich phenomenon,an illusory perception of a horizontally moving object moving in an elliptical orbit in depth.In addition,we will explore whether the modulation of the Pulfrich effect is produced in the magnocellular pathway or the parvocellular pathway,by comparing two protocols,each designed to activate one pathway at a time.Methods:The stimulus used throughout the experiment is made up of elements defining a cylinder rotating in depth,allowing to measure interocular delay.The task consists of reporting the direction of rotation of the stimulus presented.There are two different stimuli:the P stimulus is composed of small elements oscillating slowly,which stimulates the parvocellular pathway,and the M stimulus which is composed of large elements oscillating rapidly which stimulates the magnocellular pathway.One experimental session consists of pre-patch testing,one hour of patching,and a post-patch testing.Each participant performs four sessions,both stimuli for each eye.Results:The point of subjective equivalence(PSE)is extracted from psychometric functions obtained during pre-testing and post-testing.Following deprivation of the left eye the PSE shifts negatively,whereas deprivation of the right eye shifts the PSE positively on the psychometric function.This indicated that monocular deprivation slows the perceptual processes of the previously patched eye.The amplitude of this effect is larger for the M protocol than it is for the P protocol.Conclusions:Contrary to expectations,results showed that effects of monocular deprivation are not exclusively mediated by contrast gain mechanisms,as suggested by Zhou and colleagues(2014).The amplitude of the differences observed for the M protocole suggest that the plasticity induced by short term deprivation is equally subjected to dynamic components. 展开更多
关键词 monocular deprivation PLASTICITY Pulfrich phenomenon binocular vision
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AB066. Duration dependent visual plasticity via monocular deprivation
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作者 Seung Hyun Min Alex Baldwin +1 位作者 Alexandre Reynaud Robert F.Hess 《Annals of Eye Science》 2018年第1期472-472,共1页
Background:Short-term monocular deprivation has been recently shown to temporarily increase the sensitivity of the patched eye.Many studies have patched subjects for an arbitrary period of 2.5 hours,but for no princip... Background:Short-term monocular deprivation has been recently shown to temporarily increase the sensitivity of the patched eye.Many studies have patched subjects for an arbitrary period of 2.5 hours,but for no principled reason.Our goal is to show a relationship,if any,between the length of patching duration and the strength of its effect.Methods:We tested nine subjects with three different patching durations:1-,2-,3-hour.Four of the nine subjects were patched for 5-hour.Monocular deprivation was achieved by the use of a translucent eyepatch.A session included two rounds of baseline testing of interocular eye balance,patching,and post-patching tests.Each post-patching test occurred at 0,3,6,12,24,48,60 and 96 minutes after patching to track the patching effect over time.Every subject performed two sessions per condition.Results:One-hour patching produced a small shift in ocular dominance.A larger shift occurred from 2-hour patching,but 3-hour patching produced a comparable effect to the one measured after 2-hour patching.Conclusions:These results show a saturation of the patching effect beyond 2-hour patching.Hence,we believe that 2-hour patching duration is the optimal duration for eye dominance changes induced by monocular deprivation. 展开更多
关键词 NEUROPLASTICITY ocular dominance monocular deprivation
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AB012. The effects of monocular deprivation do not accumulate across days in adults with normal vision
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作者 Seung Hyun Min Alex S.Baldwin Robert F.Hess 《Annals of Eye Science》 2019年第1期187-187,共1页
Background:We investigate whether changes in visual plasticity induced by monocular deprivation can be maintained across multiple days.It has been known that monocular deprivation strengthens the deprived eye in adult... Background:We investigate whether changes in visual plasticity induced by monocular deprivation can be maintained across multiple days.It has been known that monocular deprivation strengthens the deprived eye in adults with normal vision for a short period of time(30-60 minutes).This has been shown through a variety of visual tasks such as binocular combination and rivalry.Methods:Ten subjects were recruited and patched for five consecutive days for two hours.We used a binocular phase combination task to measure the subjects’sensory eye balances.We initially measured their baseline of sensory eye balance,patched their dominant eye,and then conducted post-patching measurements at 0,3,6,12,24 and 48 minutes after patching.Results:We performed a 2-way ANOVA(Before vs.after patching×Day);we found that although the effect of monocular deprivation on the deprived eye was significant,F(1,9)=17.32,P=0.002,the effect of Day was not.Conclusions:Hence we found no accumulation of the patching effect across five days in healthy adults.This suggests that the degree of remnant neural plasticity in adult primary visual cortex may be too limited to be exploited therapeutically. 展开更多
关键词 monocular deprivation neural plasticity binocular vision
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Influences of levodopa on expression of N-methyl-D-aspartate receptor-1-subunit in the visual cortex of monocular deprivation rats 被引量:2
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作者 Xiao-Nan Sun Jin-Song Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第1期50-54,共5页
AIM: Many studies have demonstrated N-methyl-D- aspartate receptor-1-subunit (NMDAR1) is associated with amblyopia. The effectiveness of levodopa in improving the visual function of the children with amblyopia has als... AIM: Many studies have demonstrated N-methyl-D- aspartate receptor-1-subunit (NMDAR1) is associated with amblyopia. The effectiveness of levodopa in improving the visual function of the children with amblyopia has also been proved. But the mechanism is undefined. Our study was to explore the possible mechanism.METHODS: Sixty 14-day-old healthy SD rats were randomly divided into 4 groups, including normal group, monocular deprivation group, levodopa group and normal saline group, 15 rats each. We sutured all the rats' unilateral eyelids except normal group to establish the monocular deprivation animal model and raise them in normal sunlight till 45-day-old. NMDAR1 was detected in the visual cortex with immunohistochemistry methods, Western Blot and Real time PCR. LD and NS groups were gavaged with levodopa(40mg/kg) and normal saline for 28 days respectively. NMDAR1 was also detected with the methods above.RESULTS: NMDAR1 in the visual cortex of MD group was less than that of normal group. NMDAR1 in the visual cortex of LD group was more than that of NS group.CONCLUSION: NMDAR1 is associated with the plasticity of visual development. Levodopa may influence the expression of NMDAR1 and improve visual function, and its target may lie in the visual cortex. 展开更多
关键词 LEVODOPA N-METHYL-D-ASPARTATE receptor monocular deprivation
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A Dynamic and Quantitative Study of Pattern Visual Evoked Potentials and Gamma-Aminobutyric Acid Neurones in the Lateral Geniculate Nucleus and the Visual Cortex of Monocular Deprivation Cats 被引量:2
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作者 Hong Yan, Donggao Zhang, Xingguang Yang, Dan Ma, Qide JiaDepartment of Ophthalmology, Tangdu Hospital, The Fourth Military Medical University P.L.A. Institute of Neuroscience, Xian, 710038, China 《Eye Science》 CAS 1996年第3期126-134,共9页
Purpose: To assess the effects of monocular lid closure during critical period on cortical activity.Method: Pattern visual evoked potentials (PVEP) of the normal and the monocular deprivation (MD) cats were dynamicall... Purpose: To assess the effects of monocular lid closure during critical period on cortical activity.Method: Pattern visual evoked potentials (PVEP) of the normal and the monocular deprivation (MD) cats were dynamically measured and the number of gam-maaminobutyric acid immunopositive (GABA-IP) neurones of the area 17 of the visual cortex and the lateral geniculate nucleus (LGN) was quantitatively compared by using immunohistochemical method (ABC).Result: The amplitude of the N1-P1 attenuated in deprived eyes (DE) , NE/DE at postnatal week (PNW) 7-8 (P【0. 05), NE/DE at PNW 15-16 (P【0. 01); while P1 latency delayed, NE/DE at PNW 7-8 (P】0. 05), NE/DE at PNW 15 - 16(P【0. 05). The numbers of GABA-IP neurones in layer A1 of the ipsilateral LGN and in layer A of the contralateral LGN, compared to those in the corresponding normal laminae, were not significant at PNW 7 - 8 and PNW 11 - 12 (P 】0. 05), while in the same cats a reduction in the number of GABA-IP neurcnes was found in layer IV of area 17 at PNW 展开更多
关键词 monocular deprivation PVEP GABA cat
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Depth-Guided Vision Transformer With Normalizing Flows for Monocular 3D Object Detection
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作者 Cong Pan Junran Peng Zhaoxiang Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期673-689,共17页
Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input t... Monocular 3D object detection is challenging due to the lack of accurate depth information.Some methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input to augment the RGB images.Depth-based methods attempt to convert estimated depth maps to pseudo-LiDAR and then use LiDAR-based object detectors or focus on the perspective of image and depth fusion learning.However,they demonstrate limited performance and efficiency as a result of depth inaccuracy and complex fusion mode with convolutions.Different from these approaches,our proposed depth-guided vision transformer with a normalizing flows(NF-DVT)network uses normalizing flows to build priors in depth maps to achieve more accurate depth information.Then we develop a novel Swin-Transformer-based backbone with a fusion module to process RGB image patches and depth map patches with two separate branches and fuse them using cross-attention to exchange information with each other.Furthermore,with the help of pixel-wise relative depth values in depth maps,we develop new relative position embeddings in the cross-attention mechanism to capture more accurate sequence ordering of input tokens.Our method is the first Swin-Transformer-based backbone architecture for monocular 3D object detection.The experimental results on the KITTI and the challenging Waymo Open datasets show the effectiveness of our proposed method and superior performance over previous counterparts. 展开更多
关键词 monocular 3D object detection normalizing flows Swin Transformer
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Alterations of sleep deprivation on brain function:A coordinatebased resting-state functional magnetic resonance imaging metaanalysis
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作者 Qin Zhang Yong-Zhe Hou +6 位作者 Hui Ding Yan-Ping Shu Jing Li Xi-Zhao Chen Jia-Lin Li Qin Lou Dai-Xing Wang 《World Journal of Psychiatry》 SCIE 2024年第2期315-329,共15页
BACKGROUND Sleep deprivation is a prevalent issue that impacts cognitive function.Although numerous neuroimaging studies have explored the neural correlates of sleep loss,inconsistencies persist in the reported result... BACKGROUND Sleep deprivation is a prevalent issue that impacts cognitive function.Although numerous neuroimaging studies have explored the neural correlates of sleep loss,inconsistencies persist in the reported results,necessitating an investigation into the consistent brain functional changes resulting from sleep loss.AIM To establish the consistency of brain functional alterations associated with sleep deprivation through systematic searches of neuroimaging databases.Two metaanalytic methods,signed differential mapping(SDM)and activation likelihood estimation(ALE),were employed to analyze functional magnetic resonance imaging(fMRI)data.METHODS A systematic search performed according to PRISMA guidelines was conducted across multiple databases through July 29,2023.Studies that met specific inclusion criteria,focused on healthy subjects with acute sleep deprivation and reported whole-brain functional data in English were considered.A total of 21 studies were selected for SDM and ALE meta-analyses.RESULTS Twenty-one studies,including 23 experiments and 498 subjects,were included.Compared to pre-sleep deprivation,post-sleep deprivation brain function was associated with increased gray matter in the right corpus callosum and decreased activity in the left medial frontal gyrus and left inferior parietal lobule.SDM revealed increased brain functional activity in the left striatum and right central posterior gyrus and decreased activity in the right cerebellar gyrus,left middle frontal gyrus,corpus callosum,and right cuneus.CONCLUSION This meta-analysis consistently identified brain regions affected by sleep deprivation,notably the left medial frontal gyrus and corpus callosum,shedding light on the neuropathology of sleep deprivation and offering insights into its neurological impact. 展开更多
关键词 Sleep deprivation Resting-state-functional magnetic resonance imaging Activation likelihood estimation-meta Signed differential mapping-meta
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Relationship between monocularly deprivation and amblyopia rats and visual system development 被引量:6
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作者 Yu Ma 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第7期568-571,共4页
Objective:To explore the changes of lateral geniculate body and visual cortex in monocular strabismus and form deprived amblyopic rat,and visual development plastic stage and visual plasticity in adult rats.Methods:A ... Objective:To explore the changes of lateral geniculate body and visual cortex in monocular strabismus and form deprived amblyopic rat,and visual development plastic stage and visual plasticity in adult rats.Methods:A total of 60 SD rats ages 13 d were randomly divided into A,B,C three groups with 20 in each group,group A was set as the normal control group without any processing,group B was strabismus amblyopic group,using the unilateral extraocular rectus resection to establish the strabismus amblyopia model,group C was monocular form deprivation amblyopia group using unilateral eyelid edge resection+lid suture.At visual developmental early phase(P2S),meta phase(P3S),late phase(P45)and adult phase(P120),the lateral geniculate body and visual cortex area 17 of five rats in each group were exacted for C-fos Immunocytochemistry.Neuron morphological changes in lateral geniculate body and visual cortex was observed,the positive neurons differences of C-fos expression induced by light stimulation was measured in each group,and the condition of radiation development of P120 amblyopic adult rats was observed.Results:In groups B and C,C-fos positive cells were significantly lower than the control group at P25(P<0.05),there was no statistical difference of C-fos protein positive cells between group B and group A(P>0.05),C-fos protein positive cells level of group B was significantly lower than that of group A(P<0.05).The binoculus C-fos protein positive cells level of groups B and C were significantly higher than that of control group at P35,P4S and P120 with statistically significant differences(P<0.05).Conclusions:The increasing of C-fos expression in geniculate body and visual cortex neurons of adult amblyopia suggests the visual cortex neurons exist a certain degree of visual plasticity. 展开更多
关键词 deprivation AMBLYOPIA monocular STRABISMUS Visual development C-FOS
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Overexpression of Sirt6 ameliorates sleep deprivation induced-cognitive impairment by modulating glutamatergic neuron function 被引量:1
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作者 Jinpiao Zhu Chang Chen +15 位作者 Zhen Li Xiaodong Liu Jingang He Ziyue Zhao Mengying He Binbin Nie Zili Liu Yingying Chen Kuanpin Su Xiang Li Juxiang Chen Hongbing Xiang Fuqiang Xu Kangguang Lin Zongze Zhang Jie Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2449-2458,共10页
Sleep benefits the restoration of energy metabolism and thereby suppo rts neuronal plasticity and cognitive behaviors.Sirt6 is a NAD+-dependent protein deacetylase that has been recognized as an essential regulator of... Sleep benefits the restoration of energy metabolism and thereby suppo rts neuronal plasticity and cognitive behaviors.Sirt6 is a NAD+-dependent protein deacetylase that has been recognized as an essential regulator of energy metabolism because it modulates various transcriptional regulators and metabolic enzymes.The aim of this study was to investigate the influence of Sirt6 on cerebral function after chronic sleep deprivation(CSD).We assigned C57BL/6J mice to control or two CSD groups and subjected them to AAV2/9-CMV-EGFP or AAV2/9-CMV-Sirt6-EGFP infection in the prelimbic cortex(PrL).We then assessed cerebral functional connectivity(FC) using resting-state functional MRI,neuron/astrocyte metabolism using a metabolic kinetics analysis;dendritic spine densities using sparse-labeling;and miniature excitato ry postsynaptic currents(mEPSCs) and action potential(AP) firing rates using whole-cell patchclamp recordings.In addition,we evaluated cognition via a comprehensive set of behavioral tests.Compared with controls,Sirt6 was significantly decreased(P<0.05) in the PrL after CSD,accompanied by cognitive deficits and decreased FC between the PrL and accumbens nucleus,piriform cortex,motor co rtex,somatosensory co rtex,olfactory tubercle,insular cortex,and cerebellum.Sirt6 ove rexpression reve rsed CSD-induced cognitive impairment and reduced FC.Our analysis of metabolic kinetics using [1-13C] glucose and [2-13C] acetate showed that CSD reduced neuronal Glu4and GABA2synthesis,which could be fully restored via forced Sirt6 expression.Furthermore,Sirt6 ove rexpression reversed CSD-induced decreases in AP firing rates as well as the frequency and amplitude of mEPSCs in PrL pyramidal neurons.These data indicate that Sirt6 can improve cognitive impairment after CSD by regulating the PrL-associated FC network,neuronal glucose metabolism,and glutamatergic neurotransmission.Thus,Sirt6 activation may have potential as a novel strategy for treating sleep disorder-related diseases. 展开更多
关键词 chronic sleep deprivation cognitive impairment functional connectivity glutamatergic neurons metabolic kinetics neuronal-astrocytic glucose metabolism prelimbic cortex REM sleep Sirt6 synaptic function
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Neuroprotective effects of neural stem cells pretreated with neuregulin1β on PC12 cells exposed to oxygen-glucose deprivation/reoxygenation 被引量:1
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作者 Qiu-Yue Zhai Yuan-Hua Ye +4 位作者 Yu-Qian Ren Zhen-Hua Song Ke-Li Ge Bao-He Cheng Yun-Liang Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期618-625,共8页
Studies on ischemia/reperfusion(I/R)injury suggest that exogenous neural stem cells(NSCs)are ideal candidates for stem cell therapy reperfusion injury.However,NSCs are difficult to obtain owing to ethical limitations.... Studies on ischemia/reperfusion(I/R)injury suggest that exogenous neural stem cells(NSCs)are ideal candidates for stem cell therapy reperfusion injury.However,NSCs are difficult to obtain owing to ethical limitations.In addition,the survival,differentiation,and proliferation rates of transplanted exogenous NSCs are low,which limit their clinical application.Our previous study showed that neuregulin1β(NRG1β)alleviated cerebral I/R injury in rats.In this study,we aimed to induce human umbilical cord mesenchymal stem cells into NSCs and investigate the improvement effect and mechanism of NSCs pretreated with 10 nM NRG1βon PC12 cells injured by oxygen-glucose deprivation/reoxygenation(OGD/R).Our results found that 5 and 10 nM NRG1βpromoted the generation and proliferation of NSCs.Co-culture of NSCs and PC12 cells under condition of OGD/R showed that pretreatment of NSCs with NRG1βimproved the level of reactive oxygen species,malondialdehyde,glutathione,superoxide dismutase,nicotinamide adenine dinucleotide phosphate,and nuclear factor erythroid 2-related factor 2(Nrf2)and mitochondrial damage in injured PC12 cells;these indexes are related to ferroptosis.Research has reported that p53 and solute carrier family 7 member 11(SLC7A11)play vital roles in ferroptosis caused by cerebral I/R injury.Our data show that the expression of p53 was increased and the level of glutathione peroxidase 4(GPX4)was decreased after RNA interference-mediated knockdown of SLC7A11 in PC12 cells,but this change was alleviated after co-culturing NSCs with damaged PC12 cells.These findings suggest that NSCs pretreated with NRG1βexhibited neuroprotective effects on PC12 cells subjected to OGD/R through influencing the level of ferroptosis regulated by p53/SLC7A11/GPX4 pathway. 展开更多
关键词 ferroptosis p53 SLC7A11 GPX4 human umbilical cord-mesenchymal stem cells neural stem cells neuregulin1β NEUROPROTECTION oxygen-glucose deprivation/reoxygenation PC12 cell
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Local digital lending development and the incidence of deprivation in Kenya
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作者 Godsway Korku Tetteh 《Financial Innovation》 2023年第1期2856-2881,共26页
In the developing world,vulnerable communities often lack access to regular income sources to cope with unforeseen events.Recent advancements in financial technology have enabled microcredit to be delivered via digita... In the developing world,vulnerable communities often lack access to regular income sources to cope with unforeseen events.Recent advancements in financial technology have enabled microcredit to be delivered via digital platforms.Although digital credit may quicken remote access to consumer credit without the need for collateral,little is known about its contribution to the welfare of underserved communities.This study examines the effects of local digital lending development on deprivation and explores the implications of these effects on rural inhabitants.The results show a negative association between local digital lending development and food deprivation on one hand and health deprivation on the other.The evidence suggests that local digital lending development can reduce the probability of food and health deprivation.Furthermore,the evidence reveals that inhabitants of rural communities benefit more from digital lending development.This study recommends the decentralization of financial inclusion policies as a pathway to promote digital lending at the local level. 展开更多
关键词 MICROFINANCE Fintech Digital lending deprivation
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Salidroside attenuates oxygen and glucose deprivation-induced neuronal injury by inhibiting ferroptosis
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作者 Ying-Zhi Li Ai-Ping Wu +2 位作者 Dan-Dan Wang Pan-Pan Yang Bin Sheng 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第2期70-79,共10页
Objective: To evaluate the effect of salidroside on oxygen and glucose deprivation(OGD)-treated NT2 cells and its underlying mechanisms of action.Methods: Retinoic acid was used to induce the differentiation of NT2 ce... Objective: To evaluate the effect of salidroside on oxygen and glucose deprivation(OGD)-treated NT2 cells and its underlying mechanisms of action.Methods: Retinoic acid was used to induce the differentiation of NT2 cells into neurons. The effects of salidroside on survival, apoptosis, inflammatory response, and oxidative stress of neurons undergoing OGD were evaluated. Using precursor cells as controls, the effect of salidroside on the differentiation progression of OGDtreated cells was evaluated. In addition, the effect of erastin, a ferroptosis inducer, on NT2 cells was examined to investigate the underlying mechanisms of neuroprotective action of salidroside.Results: Salidroside alleviated the effects of OGD on neuronal survival, apoptosis, inflammation, and oxidative stress, and promoted NT2 cell differentiation. Moreover, salidroside prevented ferroptosis of OGD-treated cells, which was abolished following erastin treatment, indicating that ferroptosis mediated the regulatory pathway of salidroside.Conclusions: Salidroside attenuates OGD-induced neuronal injury by inhibiting ferroptosis and promotes neuronal differentiation. 展开更多
关键词 SALIDROSIDE Rhodiola rosea Ferroptosis Oxygen and glucose deprivation Neuronal differentiation Ischemic stroke
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Monocular 3D object detection with Pseudo-LiDAR confidence sampling and hierarchical geometric feature extraction in 6G network
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作者 Jianlong Zhang Guangzu Fang +3 位作者 Bin Wang Xiaobo Zhou Qingqi Pei Chen Chen 《Digital Communications and Networks》 SCIE CSCD 2023年第4期827-835,共9页
The high bandwidth and low latency of 6G network technology enable the successful application of monocular 3D object detection on vehicle platforms.Monocular 3D-object-detection-based Pseudo-LiDAR is a low-cost,lowpow... The high bandwidth and low latency of 6G network technology enable the successful application of monocular 3D object detection on vehicle platforms.Monocular 3D-object-detection-based Pseudo-LiDAR is a low-cost,lowpower solution compared to LiDAR solutions in the field of autonomous driving.However,this technique has some problems,i.e.,(1)the poor quality of generated Pseudo-LiDAR point clouds resulting from the nonlinear error distribution of monocular depth estimation and(2)the weak representation capability of point cloud features due to the neglected global geometric structure features of point clouds existing in LiDAR-based 3D detection networks.Therefore,we proposed a Pseudo-LiDAR confidence sampling strategy and a hierarchical geometric feature extraction module for monocular 3D object detection.We first designed a point cloud confidence sampling strategy based on a 3D Gaussian distribution to assign small confidence to the points with great error in depth estimation and filter them out according to the confidence.Then,we present a hierarchical geometric feature extraction module by aggregating the local neighborhood features and a dual transformer to capture the global geometric features in the point cloud.Finally,our detection framework is based on Point-Voxel-RCNN(PV-RCNN)with high-quality Pseudo-LiDAR and enriched geometric features as input.From the experimental results,our method achieves satisfactory results in monocular 3D object detection. 展开更多
关键词 monocular 3D object detection Pseudo-LiDAR Confidence sampling Hierarchical geometric feature extraction
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Monocular Depth Estimation with Sharp Boundary
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作者 Xin Yang Qingling Chang +2 位作者 Shiting Xu Xinlin Liu Yan Cui 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期573-592,共20页
Monocular depth estimation is the basic task in computer vision.Its accuracy has tremendous improvement in the decade with the development of deep learning.However,the blurry boundary in the depth map is a serious pro... Monocular depth estimation is the basic task in computer vision.Its accuracy has tremendous improvement in the decade with the development of deep learning.However,the blurry boundary in the depth map is a serious problem.Researchers find that the blurry boundary is mainly caused by two factors.First,the low-level features,containing boundary and structure information,may be lost in deep networks during the convolution process.Second,themodel ignores the errors introduced by the boundary area due to the few portions of the boundary area in the whole area,during the backpropagation.Focusing on the factors mentioned above.Two countermeasures are proposed to mitigate the boundary blur problem.Firstly,we design a scene understanding module and scale transformmodule to build a lightweight fuse feature pyramid,which can deal with low-level feature loss effectively.Secondly,we propose a boundary-aware depth loss function to pay attention to the effects of the boundary’s depth value.Extensive experiments show that our method can predict the depth maps with clearer boundaries,and the performance of the depth accuracy based on NYU-Depth V2,SUN RGB-D,and iBims-1 are competitive. 展开更多
关键词 monocular depth estimation object boundary blurry boundary scene global information feature fusion scale transform boundary aware
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Protective effect of ginsenoside Rg1 on 661W cells exposed to oxygen-glucose deprivation/reperfusion via keap1/nrf2 pathway
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作者 Ming Zhou Xin-Qi Ma +4 位作者 Yi-Yu Xie Jia-Bei Zhou Xie-Lan Kuang Huang-Xuan Shen Chong-De Long 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第7期1026-1033,共8页
AIM:To construct an in vitro model of oxygen-glucose deprivation/reperfusion(OGD/R)induced injury to the optic nerve and to study the oxidative damage mechanism of ischemia-reperfusion(I/R)injury in 661W cells and the... AIM:To construct an in vitro model of oxygen-glucose deprivation/reperfusion(OGD/R)induced injury to the optic nerve and to study the oxidative damage mechanism of ischemia-reperfusion(I/R)injury in 661W cells and the protective effect of ginsenoside Rg1.METHODS:The 661W cells were treated with different concentrations of Na2S2O4 to establish OGD/R model in vitro.Apoptosis,intracellular reactive oxygen species(ROS)levels and superoxide dismutase(SOD)levels were measured at different time points during the reperfusion injury process.The injury model was pretreated with graded concentrations of ginsenoside Rg1.Real-time polymerase chain reaction(PCR)was used to measure the expression levels of cytochrome C(cyt C)/B-cell lymphoma-2(Bcl2)/Bcl2 associated protein X(Bax),heme oxygenase-1(HO-1),caspase9,nuclear factor erythroid 2-related factor 2(nrf2),kelch-like ECH-associated protein 1(keap1)and other genes.Western blot was used to detect the expression of nrf2,phosphorylated nrf2(pnrf2)and keap1 protein levels.RESULTS:Compared to the untreated group,the cell activity of 661W cells treated with Na2S2O4 for 6 and 8h decreased(P<0.01).Additionally,the ROS content increased and SOD levels decreased significantly(P<0.01).In contrast,treatment with ginsenoside Rg1 reversed the cell viability and SOD levels in comparison to the Na_(2)S_(2)O_(4)treated group(P<0.01).Moreover,Rg1 reduced the levels of caspase3,caspase9,and cyt C,while increasing the Bcl2/Bax level.These differences were all statistically significant(P<0.05).Western blot analysis showed no significant difference in the protein expression levels of keap1 and nrf2 with Rg1 treatment,however,Rg1 significantly increased the ratio of pnrf2/nrf2 protein expression compared to the Na_(2)S_(2)O_(4)treated group(P<0.001).CONCLUSION:The OGD/R process is induced in 661W cells using Na_(2)S_(2)O_(4).Rg1 inhibits OGD/R-induced oxidative damage and alleviates the extent of apoptosis in 661W cells through the keap1/nrf2 pathway.These results suggest a potential protective effect of Rg1 against retinal I/R injury. 展开更多
关键词 oxygen-glucose deprivation/reoxygenation ginsenoside Rg1 oxidative stress phosphorylated nrf2
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Dual Branch PnP Based Network for Monocular 6D Pose Estimation
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作者 Jia-Yu Liang Hong-Bo Zhang +2 位作者 Qing Lei Ji-Xiang Du Tian-Liang Lin 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3243-3256,共14页
Monocular 6D pose estimation is a functional task in the field of com-puter vision and robotics.In recent years,2D-3D correspondence-based methods have achieved improved performance in multiview and depth data-based s... Monocular 6D pose estimation is a functional task in the field of com-puter vision and robotics.In recent years,2D-3D correspondence-based methods have achieved improved performance in multiview and depth data-based scenes.However,for monocular 6D pose estimation,these methods are affected by the prediction results of the 2D-3D correspondences and the robustness of the per-spective-n-point(PnP)algorithm.There is still a difference in the distance from the expected estimation effect.To obtain a more effective feature representation result,edge enhancement is proposed to increase the shape information of the object by analyzing the influence of inaccurate 2D-3D matching on 6D pose regression and comparing the effectiveness of the intermediate representation.Furthermore,although the transformation matrix is composed of rotation and translation matrices from 3D model points to 2D pixel points,the two variables are essentially different and the same network cannot be used for both variables in the regression process.Therefore,to improve the effectiveness of the PnP algo-rithm,this paper designs a dual-branch PnP network to predict rotation and trans-lation information.Finally,the proposed method is verified on the public LM,LM-O and YCB-Video datasets.The ADD(S)values of the proposed method are 94.2 and 62.84 on the LM and LM-O datasets,respectively.The AUC of ADD(-S)value on YCB-Video is 81.1.These experimental results show that the performance of the proposed method is superior to that of similar methods. 展开更多
关键词 6D pose monocular RGB edge enhancement dual-branch PnP 2D-3D correspondence
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Establishment of oxygen glucose deprivation reperfusion model of senescent SH-SY5Y cells
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作者 ZHANG Qiao-tian JIANG Chang-yue +3 位作者 ZHU GE Xiang-zhen LI De-li HU Wan-Xiang XIE Lu 《Journal of Hainan Medical University》 CAS 2023年第6期1-7,共7页
Obejective:To explore the establishment of an oxygen glucose deprivation/reperfusion model of senescent SH-SY5Y cells.Methods:SH-SY5Y cells were randomly divided into control(D-galactose 0 mmol/L group),D-galactose(25... Obejective:To explore the establishment of an oxygen glucose deprivation/reperfusion model of senescent SH-SY5Y cells.Methods:SH-SY5Y cells were randomly divided into control(D-galactose 0 mmol/L group),D-galactose(25 mmol/L,50 mmol/L,100 mmol/L,200 mmol/L,400 mmol/L)groups,and treated with corresponding concentrations of D-galactose for 48 h.The changes of cell morphology,β-galactosidase,the cell morphology,β-galactosidase activity by microscopic observation,cell proliferation rate by EdU kit and cell survival rate by CCK-8 assay were used to determine the decaying concentration of D-galactose and to establish the senescence model.The senescent SH-SY5Y cells were randomly divided into control group(oxygen glucose deprivation without treatment group),oxygen glucose deprivation treatment(0.5 h,1 h,1.5 h,2 h)group,followed by re-glucose reoxygenation for 24 h,and CCK-8 assay for the survival rate of senescent SH-SY5Y cells.Results:There were no significant changes in cell morphology and β-gal activity in the 25 mmol/L and 50 mmol/L groups compared with the control group(P>0.05),cytosolic hypertrophy was seen in the cells of the 100 mmol/L group,chromatin fixation in the cells of the 200 mmol/L group,and massive vacuolization in the cells of the 400 mmol/L group;the positive rate ofβ-galactosidase staining in the cells of the(100-400 mmol/L)group was significantly higher compared with the control group(P<0.05),with little difference between the 100 mmol/L and 200 mmol/L groups(P>0.05);the cell proliferation ability of the(100-400 mmol/L)group was significantly decreased in a concentration-dependent manner(P<0.05);the cell survival rate was decreased in a concentration-dependent manner(P<0.05),with IC_(50) between 100 mmol/L and 200 mmol/L.The survival of senescent SH-SY5Y cells showed a time-dependent decrease in oxygen-glucose deprivation(P<0.05),with an IC_(50) close to 1 h.Conclusion:D-gal concentration of 100 mmoL/L and 48 h of cell action could establish a survival rate of about 50%of senescent SH-SY5Y cells,and oxygen glucose deprivation of senescent SH-SY5Y cells for 1 h and reperfusion for 24 h could establish an oxygen glucose deprivation/reperfusion model of senescent SH-SY5Y cells with a survival rate close to 50%. 展开更多
关键词 Cerebral ischemia-reperfusion injury Oxygen glucose deprivation reperfusion AGING D-GALACTOSE SH-SY5Y cell
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壳三糖和壳五糖对睡眠剥夺小鼠学习记忆障碍的影响
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作者 王斌 顾娟 +6 位作者 闫华 赵宁静 刘楠晖 张澎竹 姜启兴 许艳顺 夏文水 《食品与发酵工业》 CAS CSCD 北大核心 2024年第7期32-38,共7页
各种原因引起的睡眠时间减少已成为生活常态,睡眠剥夺会降低机体的学习记忆能力,影响生活质量。该研究对C57BL/6J小鼠进行21 d睡眠剥夺,同时每天对小鼠灌胃壳三糖(chitotriose,COS3)和壳五糖(chitopentaose,COS5),通过体重、新物体识别... 各种原因引起的睡眠时间减少已成为生活常态,睡眠剥夺会降低机体的学习记忆能力,影响生活质量。该研究对C57BL/6J小鼠进行21 d睡眠剥夺,同时每天对小鼠灌胃壳三糖(chitotriose,COS3)和壳五糖(chitopentaose,COS5),通过体重、新物体识别实验、病理学染色、氧化应激和凋亡相关蛋白表达评估COS3和COS5的保护作用。结果显示,COS3和COS5干预能够缓解小鼠体重下降和海马神经细胞坏死变形,显著提高海马组织中超氧化物歧化酶水平和总抗氧化能力,显著降低海马丙二醛含量。COS3和COS5干预能够显著提升海马p-PI3K(phospho-phosphotylinosital 3 kinase)和p-Akt(phospho-protein kinase B)蛋白的相对表达量,激活PI3K/Akt信号通路,缓解神经细胞凋亡。研究表明,COS3和COS5能够明显改善睡眠剥夺引起的学习记忆能力下降,其机制可能与COS3和COS5能够缓解海马组织氧化应激和神经细胞凋亡有关,其中COS3的效果优于COS5。 展开更多
关键词 壳寡糖 睡眠剥夺 学习记忆 氧化应激 凋亡
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一种四轴飞行器单目视觉测距算法
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作者 顾兆军 韩强 +2 位作者 王家亮 陈辉 董楷 《小型微型计算机系统》 CSCD 北大核心 2024年第1期199-206,共8页
为解决四轴飞行器在执行目标检测与跟踪任务时无法判断机身与障碍物或跟踪目标之间安全距离问题,提出一种四轴飞行器单目视觉测距算法,算法融合基于帧间差分技术的水平测距模型与基于小孔成像的垂直测距模型.首先,算法可利用基于YOLOV4-... 为解决四轴飞行器在执行目标检测与跟踪任务时无法判断机身与障碍物或跟踪目标之间安全距离问题,提出一种四轴飞行器单目视觉测距算法,算法融合基于帧间差分技术的水平测距模型与基于小孔成像的垂直测距模型.首先,算法可利用基于YOLOV4-Tiny的目标检测算法识别视频帧中的物体类别,并可在视频帧中框选出被测物体,依据现场环境选择最佳的测距方法进行测距;其次,系统终端执行测距方法,基于被测物体的视频帧成像位置与设定参数之间的差值控制四轴飞行器飞行,并记录飞行数据;最后,通过测距模型对飞行数据进行处理,计算出四轴飞行器在初始位置和最终位置与被测物体之间的距离.通过在特洛(Tello)飞行器平台上的实际飞行验证,实验结果表明所提出的四轴飞行器单目视觉测距算法可以有效分析出视频帧中各物体的景深,测距误差百分比均值为4.07%.在四轴飞行器与障碍物或跟踪目标之间距离较近,却无法评估此距离是否处于安全距离时,所提出的算法可为搭载单目摄像头的四轴飞行器提供可靠的测距技术支持. 展开更多
关键词 单目视觉 四轴飞行器 目标跟踪 帧间差分 测距
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应用激光跟踪仪和单目视觉检测三维水模体定位精度方法研究
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作者 韩连福 褚芃 +3 位作者 罗明哲 白娴靓 李加福 朱小平 《中国测试》 CAS 北大核心 2024年第2期14-21,共8页
针对三维水模体检测方法较少、检测过程复杂等问题,提出基于激光跟踪仪和单目视觉的三维水模体定位精度检测方法。激光跟踪仪三维水模体定位精度检测对比实验验证三维水模体在有水和无水的情况下定位精度一致。单目视觉三维水模体定位... 针对三维水模体检测方法较少、检测过程复杂等问题,提出基于激光跟踪仪和单目视觉的三维水模体定位精度检测方法。激光跟踪仪三维水模体定位精度检测对比实验验证三维水模体在有水和无水的情况下定位精度一致。单目视觉三维水模体定位精度检测实验结果表明:X轴、Y轴、Z轴和空间对角线的定位误差均在0.050 mm以内,重复性分别为0.030 mm,0.064 mm,0.056 mm,0.140 mm,X轴和Y轴的垂直度为0.800 mm,Y轴和Z轴的垂直度为0.761 mm,X轴和Z轴的垂直度为0.503 mm,与激光跟踪仪的测量精度在一个量级。最后,经不确定度分析得到相邻点距离测量误差的标准差为0.0187 mm,满足检测要求。两种方法都能实现非接触测量,简化冗杂的检测过程,可满足医院对医用直线加速器的日常检测需求。 展开更多
关键词 三维水模体 激光跟踪仪 单目视觉 定位精度
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