Promotion of structural plasticity in area V2 of visual cortex prevents against object recognition memory deficits in aging and Alzheimer's disease rodents

Memory deficit,which is often associated with aging and many psychiatric,neurological,and neurodegenerative diseases,has been a challenging issue for treatment.Up till now,all potential drug candidates have failed to produce satisfa ctory effects.Therefore,in the search for a solution,we found that a treatment with the gene corresponding to the RGS14414protein in visual area V2,a brain area connected with brain circuits of the ventral stream and the medial temporal lobe,which is crucial for object recognition memory(ORM),can induce enhancement of ORM.In this study,we demonstrated that the same treatment with RGS14414in visual area V2,which is relatively unaffected in neurodegenerative diseases such as Alzheimer s disease,produced longlasting enhancement of ORM in young animals and prevent ORM deficits in rodent models of aging and Alzheimer’s disease.Furthermore,we found that the prevention of memory deficits was mediated through the upregulation of neuronal arbo rization and spine density,as well as an increase in brain-derived neurotrophic factor(BDNF).A knockdown of BDNF gene in RGS14414-treated aging rats and Alzheimer s disease model mice caused complete loss in the upregulation of neuronal structural plasticity and in the prevention of ORM deficits.These findings suggest that BDNF-mediated neuronal structural plasticity in area V2 is crucial in the prevention of memory deficits in RGS14414-treated rodent models of aging and Alzheimer’s disease.Therefore,our findings of RGS14414gene-mediated activation of neuronal circuits in visual area V2 have therapeutic relevance in the treatment of memory deficits.

Role of Cannabinoid CB1 Receptor in Object Recognition Memory Impairment in Chronically Rapid Eye Movement Sleep-deprived Rats

Objective We aimed to investigate whether antagonism of the cannabinoid CB1 receptor(CB1R)could affect novel object recognition(NOR)memory in chronically rapid eye movement sleep-deprived(RSD)rats.Methods The animals were examined for recognition memory following a 7-day chronic partial RSD paradigm using the multiple platform technique.The CB1R antagonist rimonabant(1 or 3 mg/kg,i.p.)was administered either at one hour prior to the sample phase for acquisition,or immediately after the sample phase for consolidation,or at one hour before the test phase for retrieval of NOR memory.For the reconsolidation task,rimonabant was administered immediately after the second sample phase.Results The RSD episode impaired acquisition,consolidation,and retrieval,but it did not affect the reconsolidation of NOR memory.Rimonabant administration did not affect acquisition,consolidation,and reconsolidation;however,it attenuated impairment of the retrieval of NOR memory induced by chronic RSD.Conclusions These findings,along with our previous report,would seem to suggest that RSD may affect different phases of recognition memory based on its duration.Importantly,it seems that the CB1R may,at least in part,be involved in the adverse effects of chronic RSD on the retrieval,but not in the acquisition,consolidation,and reconsolidation,of NOR memory.

Melatonin Enhances Object Recognition Memory through Melatonin MT1 and MT2 Receptor-Mediated and Non-Receptor-Mediated Mechanisms in Male Mice

Melatonin (MEL) has been reported to have acute enhancing effects on some aspects of cognition. Recently, we revealed that N1-acetyl-5-methoxyquinuramine (AMK), a brain metabolite of MEL, is much more potent than MEL in converting short-term memory (STM) to long-term memory (LTM) with a single administration immediately after the acquisition trial of the novel object recognition (NOR) task. These data suggest that the memory-enhancing effects of MEL may be mediated by mechanisms independent of the activation of MEL MT1 and MT2 receptors. In the present study, we examined the contribution of MT1 and MT2 receptor-mediated and non-receptor-mediated mechanisms to the acute memory-enhancing effects of MEL using NOR task. Mice were administered with either MEL, AMK, or a highly selective MT1/MT2 receptor agonist ramelteon (RAM) immediately after the acquisition trial and the effects of varying doses of these drugs on both STM and LTM performance were compared. We found that both AMK and RAM were more potent than MEL in both facilitating STM and promoting LTM formation. We also found that pretreatment with luzindole, a MT1/MT2 receptor antagonist, markedly suppressed only the effects of RAM. These results suggest that acutely administered MEL enhances NOR memory through both MT1 and MT2 receptor-mediated and non-receptor-mediated mechanisms.

Optogenetics-induced activation of glutamate receptors improves memory function in mice with Alzheimer’s disease

Optogenetics is a combination of optics and genetics technology that can be used to activate or inhibit specific cells in tissues. It has been used to treat Parkinson’s disease, epilepsy and neurological diseases, but rarely Alzheimer’s disease. Adeno-associated virus carrying the CaMK promoter driving the optogenetic channelrhodopsin-2 (CHR2) gene (or without the CHR2 gene, as control) was injected into the bilateral dentate gyri, followed by repeated intrahippocampal injections of soluble low-molecular-weight amyloid-β1–42 peptide (Aβ1–42). Subsequently, the region was stimulated with a 473 nm laser (1–3 ms, 10 Hz, 5 minutes). The novel object recognition test was conducted to test memory function in mice. Immunohistochemical staining was performed to analyze the numbers of NeuN and synapsin Ia/b-positive cells in the hippocampus. Western blot assay was carried out to analyze the expression levels of glial fibrillary acidic protein, NeuN, synapsin Ia/b, metabotropic glutamate receptor-1a (mGluR-1a), mGluR-5, N-methyl-D-aspartate receptor subunit NR1, glutamate receptor 2, interleukin-1β, interleukin-6 and interleukin-10. Optogenetic stimulation improved working and short-term memory in mice with Alzheimer’s disease. This neuroprotective effect was associated with increased expression of NR1, glutamate receptor 2 and mGluR-5 in the hippocampus, and decreased expression of glial fibrillary acidic protein and interleukin-6. Our results show that optogenetics can be used to regulate the neuronal-glial network to ameliorate memory functions in mice with Alzheimer’s disease. The study was approved by the Animal Resources Committee of Jinan University, China (approval No. LL-KT-2011134) on February 28, 2011.

Conditional Random Field Tracking Model Based on a Visual Long Short Term Memory Network

In dense pedestrian tracking,frequent object occlusions and close distances between objects cause difficulty when accurately estimating object trajectories.In this study,a conditional random field tracking model is established by using a visual long short term memory network in the three-dimensional(3D)space and the motion estimations jointly performed on object trajectory segments.Object visual field information is added to the long short term memory network to improve the accuracy of the motion related object pair selection and motion estimation.To address the uncertainty of the length and interval of trajectory segments,a multimode long short term memory network is proposed for the object motion estimation.The tracking performance is evaluated using the PETS2009 dataset.The experimental results show that the proposed method achieves better performance than the tracking methods based on the independent motion estimation.

Encoding of local and global cues in domestic dogs’ spatial working memory

The current study investigated whether domestic dogs encode local and/or global cues in spatial working memory. Seven dogs were trained to use a source of allocentric information (local and/or global cues) to locate an attractive object they saw move and disappear behind one of the three opaque boxes arrayed in front of them. To do so, after the disappearance of the target object and out of the dogs’ knowledge, all sources of allocentric information were simultaneously shifted to a new spatial position and the dogs were forced to follow a U-shaped pathway leading to the hiding box. Out of the seven dogs that were trained in the detour problem, only three dogs learned to use the cues that were moved from trial to trial. On tests, local (boxes and experimenter) and/or global cues (walls of the room) were systematically and drastically shifted to a new position in the testing chamber. Although they easily succeeded the control trials, the three dogs failed to use a specific source of allocentric information when local and global cues were put in conflict. In discussion, we explore several hypotheses to explain why dogs have difficulties to use allocentric cues to locate a hidden object in a detour problem and why they do not differentiate the local and global cues in this particular experimental setting.

Episodic Learning and Memory in Prodromal Huntington’s Disease: The Role of Multimodal Encoding and Selective Reminding

This study investigated episodic memory in prodromal HD. Three groups were compared (N = 70): mutation carriers with less than 12.5 years to disease onset (n = 16), mutation carriers with 12.5 or more years to disease onset (n = 16), and noncarriers (n = 38). Episodic memory was assessed using the Fuld Object Memory Evaluation, which included multimodal presentation and selective reminding, and the Claeson-Dahl Learning Test which included verbal repeated presentation and recall trials. Both carrier groups demonstrated deficient episodic memory compared to noncarriers. The results suggest deficient episodic memory in prodromal HD, and that inconsistent retrieval contributes to these deficits. Multimodal presentation attenuates the deficits.

Blade of Remembrance： Memory, Objects, and Redemption in Lu Xun

Critics have observed that memory is an important theme in Lu Xun＇s writings. At the same time, memory--more precisely a struggle over the shaping of cultural memory--is a vital component of the iconoclastic May Fourth Movement with which Lu Xun is strongly associated. This article examines the ways in which several of Lu Xun＇s creative writings and memoirs depict memory and its transmission. I argue that, 1） These texts suggest the importance of objects as mnemonic devices that aid the transmission of memory, 2） The agency of the receiver is key in interpreting these texts and in transmitting them onward, and 3） That Lu Xun posits the texts he creates as such mnemonic objects that serve to transmit his interpretation of cultural and personal memory to his readers. Lu Xun＇s texts thus implicate the reader in the author＇s project of transmitting onward his reinterpretation of the past in the hope of redeeming China. Examining these mechanisms of memory transmission I conclude that for Lu Xun redemption lies not in a transcendent future but in reexamining the past.

Novel object recognition is not affected by age despite age-related brain changes

Age-related memory impairments show a progressive decline across lifespan. Studies have demonstrated equivocal results in biological and behavioral outcomes of aging. Thus, in the present study we examined the novel object recognition task at a delay period that has been shown to be impaired in aged rats of two different strains. Moreover, we used a strain of rats, Fisher 344XBrown Norway, which have published age-related biological changes in the brain. Young (10 month old) and aged (28 month old) rats were tested on a standard novel object recognition task with a 50-minute delay period. The data showed that young and aged rats in the strain we used performed equally well on the novel object recognition task and that both young and old rats demonstrated a righthanded side preference for the novel object. Our data suggested that novel object recognition is not impaired in aged rats although both young and old rats have a demonstrated side preference. Thus, it may be that genetic differences across strains contribute to the equivocal results in behavior, and genetic variance likely influences the course of cognitive aging.

IoT-Driven Optimal Lightweight RetinaNet-Based Object Detection for Visually Impaired People

Visual impairment is one of the major problems among people of all age groups across the globe.Visually Impaired Persons(VIPs)require help from others to carry out their day-to-day tasks.Since they experience several problems in their daily lives,technical intervention can help them resolve the challenges.In this background,an automatic object detection tool is the need of the hour to empower VIPs with safe navigation.The recent advances in the Internet of Things(IoT)and Deep Learning(DL)techniques make it possible.The current study proposes IoT-assisted Transient Search Optimization with a Lightweight RetinaNetbased object detection(TSOLWR-ODVIP)model to help VIPs.The primary aim of the presented TSOLWR-ODVIP technique is to identify different objects surrounding VIPs and to convey the information via audio message to them.For data acquisition,IoT devices are used in this study.Then,the Lightweight RetinaNet(LWR)model is applied to detect objects accurately.Next,the TSO algorithm is employed for fine-tuning the hyperparameters involved in the LWR model.Finally,the Long Short-Term Memory(LSTM)model is exploited for classifying objects.The performance of the proposed TSOLWR-ODVIP technique was evaluated using a set of objects,and the results were examined under distinct aspects.The comparison study outcomes confirmed that the TSOLWR-ODVIP model could effectually detect and classify the objects,enhancing the quality of life of VIPs.

突发自然灾害下的两阶段多目标应急物资中心选址问题研究

针对突发灾害情况下需求不确定的选址问题,构建最小化经济成本和最大化满意度的应急物资中心选址模型。首先,将选址问题划分为初期和后期的两阶段问题;其次,对物资需求量进行模糊需求预测,并使用可信性模糊机会约束规划将其转化为确定型约束;最后,设计改进灰狼优化(Improved Grey Wolf Optimization,IGWO)算法求解问题。IGWO算法采用佳点集初始化种群,对收敛因子进行余弦规律的非线性变化,并在粒子群优化(Particle Swarm Optimization,PSO)算法个体记忆的启发下,设计个体位置更新公式。在用10个标准函数验证IGWO有效性的基础上,通过湖北省新型冠状病毒应急物资中心选址案例分析,表明IGWO算法能有效求解多目标选址问题,在提高满意度的基础上降低经济成本,且多阶段模型在平衡满意度和经济成本方面结果更优。

基于多尺度特征增强与全局-局部特征聚合的视频目标分割算法

针对记忆网络算法中多尺度特征表达能力不足和浅层特征没有充分利用的问题,该文提出一种多尺度特征增强与全局-局部特征聚合的视频目标分割(VOS)算法。首先,通过多尺度特征增强模块融合可参考掩码分支和可参考RGB分支的不同尺度特征信息,增强多尺度特征的表达能力;同时,建立了全局-局部特征聚合模块,利用不同大小感受野的卷积操作来提取特征,并通过特征聚合模块来自适应地融合全局区域和局部区域的特征,这种融合方式可以更好地捕捉目标的全局特征和细节信息,提高分割的准确性;最后,设计了跨层融合模块,利用浅层特征的空间细节信息来提升分割掩码的精度,通过将浅层特征与深层特征融合,能更好地捕捉目标的细节和边缘信息。实验结果表明,在公开数据集DAVIS2016,DAVIS2017和YouTube-2018上,该文算法的综合性能分别达到91.8%、84.5%和83.0%,在单目标和多目标分割任务上都能实时运行。

基于数据驱动660 MW循环流化床锅炉多目标燃烧优化

为降低某电厂循环流化床锅炉污染物排放,同时提高锅炉燃烧运行经济性,本文采用数据驱动技术实现循环流化床锅炉多目标燃烧优化。基于改进粒子群优化长短期记忆神经网络建立循环流化床锅炉NO_(x)/SO_(2)排放数学模型和锅炉排烟温度数学模型,以相对误差为预测性评估指标以确定最佳网络参数;其次,基于改进粒子群优化长短期记忆神经网络(IPSO-LSTM)、长短期记忆神经网络(LSTM)、广义回归神经网络(GRNN)和反向传播神经网络(BPNN)分别构建NO_(x)/SO_(2)排放数学模型和锅炉排烟温度数学模型,通过比较预测性评估指标,证明本文构建预测模型有效性;最后,基于非支配排序遗传算法(NSGA-Ⅱ)获取不同运行工况下循环流化床锅炉燃烧优化调整方案,以降低NO_(x)/SO_(2)排放浓度,同时维持排烟温度稳定性。结果表明:相比优化前,优化后NO_(x)排放浓度平均降低了10.58%,SO_(2)排放浓度平均降低了25.81%,最大降低了650 mg/m^(3),且排烟温度平均降低0.14%。

基于改进VisionTransformer模型的团队体育视频多目标跟踪深度学习框架

多目标跟踪(MOT)技术为团队体育视频监测和分析提供了全新的可能性,能够实时跟踪多个运动员并支持对比赛动态的多维度分析与理解。然而,在复杂的团队运动场景下,诸如运动员之间的相互遮挡、快速移动以及目标身份的频繁变换等问题,都可能降低跟踪性能。为此,本文提出了基于VisionTransformer的端到端深度学习MOT框架,主要包括检测网络和记忆网络两个部分。检测网络由卷积神经网络(CNN)骨干网、VisionTransformer编码器和解码器组成,采用ResNet50作为特征提取器,并引入局部注意力(LA)模块替代传统前馈神经网络(FFN)层。通过全局注意力和局部卷积的结合,得到更全面的特征表示。记忆网络由记忆编码模块和时空记忆解码器组成。记忆编码模块负责聚合目标嵌入信息,其中,短时互注意力(CA)模块关注即时状态,而长时记忆CA模块则挖掘了记忆涵盖的时间跨度内的显著特征,捕捉长时间间隔内的依赖关系和关联,从而有效保留了跟踪对象的时间上下文信息。时空记忆解码器在嵌入融合过程中综合考虑了编码帧、候选嵌入和轨迹嵌入信息,解决了MOT中的多目标检测和身份关联。时空记忆机制能够有效地保留目标历史状态的观察结果,并结合注意力机制对目标状态进行准确预测。实验结果表明,所提框架在团队体育视频公开数据集SportsMOT上实现了75.7%的HOTA和98.5%的MOTA结果,优于其他先进的MOT方法。此外,所提框架在通用公开数据集MOT17和MOT20上的多个指标取得了最优或次优性能,进一步验证了所提方法的有效性和鲁棒性。

情绪唤醒对联结记忆的影响:联结对应关系的作用

在验证Mather(2007)基于客体的框架基础上,采用联结再认范式进一步考查了联结对应关系和情绪唤醒对项目内、项目间联结记忆的影响。实验1在控制联结对应关系为“多对一”的条件下,直接比较了情绪对项目内、项目间联结记忆的影响。结果发现,情绪唤醒对项目内联结记忆产生了增强作用,但有损害项目间联结记忆的趋势。实验2则控制联结对应关系为“一对一”,结果发现情绪唤醒损害项目内联结记忆,不影响项目间联结记忆。这表明,情绪唤醒对联结记忆的不同影响不仅和联结记忆类型有关,还与联结对应关系有关。

人工智能影像时间性危机的理论反思与实践对策

当前,人工智能影像的应用方兴未艾,人们试图通过人工智能影像追寻逝去的时光,但是这样的愿望不仅无法实现,还造成了更深层次的时间性危机。首先,与其说人工智能影像帮助人们封存过去的时间,不如说它通过生动的影像形式把过去的时间固结成了权力的印记。其次,人工智能影像带来的“第四记忆”无法帮助人们更好地记忆过去的时间,却会导致个性化的记忆丧失,算法成为记忆建构的主导性力量,进而形成客体化的记忆体系。最后,平台化使用的前景让人工智能影像具有沦为“时间客体”的风险,将会加剧人们主体身份的迷失、经验的丧失和集体交互的缺失,进而造成资本逻辑对大众欲望的精准算计。已经出现的互动式影像对解决人工智能影像的时间性困境具有一定启发意义,通过影像的差异化重复与启发式中断,人们能够领会自身的主体身份,从而重新创造关于过去的叙事。未来,需要引导人工智能技术成为辅助性的角色,以智能式的互动影像引导公众自主建构生命叙事,从而以现实实践面对当下、创造未来。

基于掩码记忆的无人机电力设备分割跟踪方法研究

无人机巡检是保障新型电力系统安全运行的重要手段,视频目标跟踪技术能够有效提高巡检精度。针对实际电力场景中背景复杂、目标形变大等挑战,提出一种基于掩码记忆的无人机电力设备分割跟踪方法。首先,设计了基于掩码记忆的L2匹配分割方法,使用负平方欧几里得距离来计算帧间亲和度,利用构建的历史掩码信息进行目标匹配,提升设备的粗分割精度。其次,为了减少记忆冗余,提出变化感知的记忆更新机制,通过图像和掩码联合评估目标变化程度,设计变化度置信度阈值,以此决策是否进行记忆更新。最后,将分割技术融入判别式相关滤波的跟踪框架中,实现电力设备鲁棒分割跟踪。该方法分别在通用数据集VOT2018、无人机数据集UAV123和实际电力场景数据集中进行测试。实验结果表明所提方法能有效提升无人机巡检精度,并为电力设备安全运行提供技术参考。

基于编码记忆网络的半监督视频目标分割方法

视频目标分割是计算机视觉中的一项关键任务,在自动驾驶、视频编码等领域具有重要意义。针对视频目标分割任务,提出使用一种高效的编码记忆网络(EMNet)实现半监督视频目标分割任务。该方法包含自适应参考帧选取模块、双路径匹配模块、特征处理模块以及特征聚合模块。自适应参考帧选取模块综合考虑掩码置信度和相似度,选择包含丰富信息的参考帧。双路径匹配模块实现查询帧和参考帧之间的双向和双尺度匹配,提高目标特征匹配准确率。特征处理模块分别包含语义强化模块和特征细化模块,通过低通和高通滤波增强目标的语义和细节信息。并由特征聚合模块对各特征进行融合利用。最后通过在DAVIS2017数据集上的评估,证明所提出模型的有效性。

融合时空记忆网络的无监督视频多目标分割算法

无监督视频多目标分割是一种无需人工干预的技术,能够通过自动化方法在视频中同时识别并分割多个目标对象。在复杂多样的背景下,由于缺乏对主要目标的先验知识,准确识别和分割多个目标是无监督视频分割任务的主要挑战。为了解决这一问题,提出了一种融合时空记忆网络的高效无监督视频多目标分割模型。该模型主要由实例识别网络和时空记忆网络组成。实例识别网络将前景估计与实例分割相结合,通过引入时间指导模块,利用前一帧的结果来指导当前帧的分割。时空记忆网络充分利用视频中的时间信息,弥补了实例识别网络在分割过程中对前后帧关联信息的不足。实例识别网络生成的第一帧分割掩码被用作输入,随后时空记忆网络生成相应帧的目标掩码,通过将两个网络生成的掩码进行融合,得到多目标分割结果。实际应用中需要直观地提取每帧的前景目标和相应的背景图像,精准地识别出视频中的显著目标,并将其与复杂的背景区分开来。对生成的掩码图像进行进一步处理,并将其与原视频帧叠加,从而获取每帧的前景目标和背景图像。在密集标注视频分割2016和密集标注视频分割2017两个数据集上的实验表明,所提出的方法在分割精度等方面优于大多数现有的先进方法。