Transthyretin (TTR), a carrier protein present in the liver and choroid plexus of the brain, has been shown to be responsible for binding thyroid hormone thyroxin (T4) and retinol in plasma and cerebrospinal fluid (CS...Transthyretin (TTR), a carrier protein present in the liver and choroid plexus of the brain, has been shown to be responsible for binding thyroid hormone thyroxin (T4) and retinol in plasma and cerebrospinal fluid (CSF). TTR aids in sequestering of beta-amyloid peptides Aβ deposition, and protects the brain from trauma, ischemic stroke and Alzheimer disease (AD). Accordingly, hippocampal gene expression of TTR plays a significant role in learning and memory as well as in simulation of spatial memory tasks. TTR via interacting with transcription factor CREB regulates this process and decreased expression leads to memory deficits. By different signaling pathways, like MAPK, AKT, and ERK via Src, TTR provides tropical support through megalin receptor by promoting neurite outgrowth and protecting the neurons from traumatic brain injury. TTR is also responsible for the transient rise in intracellular Ca2+ via NMDA receptor, playing a dominant role under excitotoxic conditions. In this review, we tried to shed light on how TTR is involved in maintaining normal cognitive processes, its role in learning and memory, under memory deficit conditions;by which mechanisms it promotes neurite outgrowth;and how it protects the brain from Alzheimer disease (AD).展开更多
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, bu...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.展开更多
There are presently no in-depth published neuropsychological studies of West Nile Virus (WNV) encephalitis patients that have been well-correlated with high resolution structural MRI. In this study a middleaged male w...There are presently no in-depth published neuropsychological studies of West Nile Virus (WNV) encephalitis patients that have been well-correlated with high resolution structural MRI. In this study a middleaged male who developed West Nile Virus encephalitis five years previously was examined three times over a two year period. We examined him with the Wechsler Adult Intelligence Scales—Fourth Edition and the Wechsler Memory Scale—Fourth Edition (WAIS-IV/WMS-IV) and Advanced Clinical Solutions battery supplemented by tests of attention, executive, motor and sensory functions. Neuroradiological imaging revealed hypodensities within the left hippocampus in the axial and coronal planes with T2-FLAIR MRI. The man was previously high functioning and although he had prior history of well-controlled epilepsy it seems unlikely that the epilepsy could fully account for the neuropathological changes. The patient had previously completed a demanding six year double science degree program before he became ill with WNV and he had been a successful manager and director of a research company. Delayed auditory memory scores were at least two standard deviation units below age expected levels and semantic fluency and Booklet Category Tests of executive function were also in the impaired range. Moreover the illness onset profile of muscle weakness, extreme fatigue, memory complaints as well as inability to carry out research projects involving planning on the job were highly consistent with WNV encephalitis. If the memory and executive function deficits had been premorbid manifestations of epilepsy it is unlikely he would have attained the levels he did educationally and occupationally. This left hippocampal lesion is characteristic of other encephalitic viral infections such as herpes simplex virus. To our knowledge this is the first lateralized WNV encephalitis medial temporal lobe patient in the published literature.展开更多
Oxidative stress is involved in the pathogenesis of vascular dementia. Studies have shown that lycopene can significantly inhibit oxidative stress;therefore, we hypothesized that lycopene can reduce the level of oxida...Oxidative stress is involved in the pathogenesis of vascular dementia. Studies have shown that lycopene can significantly inhibit oxidative stress;therefore, we hypothesized that lycopene can reduce the level of oxidative stress in vascular dementia. A vascular dementia model was established by permanent bilateral ligation of common carotid arteries. The dosage groups were treated with lycopene(50, 100 and 200 mg/kg) every other day for 2 months. Rats without bilateral carotid artery ligation were prepared as a sham group. To test the ability of learning and memory, the Morris water maze was used to detect the average escape latency and the change of search strategy. Hematoxylin-eosin staining was used to observe changes of hippocampal neurons. The levels of oxidative stress factors, superoxide dismutase and malondialdehyde, were measured in the hippocampus by biochemical detection. The levels of reactive oxygen species in the hippocampus were observed by dihydroethidium staining. The distribution and expression of oxidative stress related protein, neuron-restrictive silencer factor, in hippocampal neurons were detected by immunofluorescence histochemistry and western blot assays. After 2 months of drug administration,(1) in the model group, the average escape latency was longer than that of the sham group, and the proportion of straight and tend tactics was lower than that of the sham group, and the hippocampal neurons were irregularly arranged and the cytoplasm was hyperchromatic.(2) The levels of reactive oxygen species and malondialdehyde in the hippocampus of the model group rats were increased, and the activity of superoxide dismutase was decreased.(3) Lycopene(50, 100 and 200 mg/kg) intervention improved the above changes, and the lycopene 100 mg/kg group showed the most significant improvement effect.(4) Neuron-restrictive silencer factor expression in the hippocampus was lower in the sham group and the lycopene 100 mg/kg group than in the model group.(5) The above data indicate that lycopene 100 mg/kg could protect against the learning-memory ability impairment of vascular dementia rats. The protective mechanism was achieved by inhibiting oxidative stress in the hippocampus. The experiment was approved by the Animal Ethics Committee of Fujian Medical University, China(approval No. 2014-025) in June 2014.展开更多
The α5 subunit-containing gamma-amino butyric acid type A receptors(α5 GABAARs) are a distinct subpopulation that are specifically distributed in the mammalian hippocampus and also mediate tonic inhibitory currents ...The α5 subunit-containing gamma-amino butyric acid type A receptors(α5 GABAARs) are a distinct subpopulation that are specifically distributed in the mammalian hippocampus and also mediate tonic inhibitory currents in hippocampal neurons. These tonic currents can be enhanced by low-dose isoflurane, which is associated with learning and memory impairment. Inverse agonists of α5 GABAARs, such as L-655,708, are able to reverse the short-term memory deficit caused by low-dose isoflurane in young animals. However, whether these negative allosteric modulators have the same effects on aged rats remains unclear. In the present study, we mainly investigated the effects of L-655,708 on low-dose(1.3%) isoflurane-induced learning and memory impairment in elderly rats. Young(3-month-old) and aged(24-month-old) Wistar rats were randomly assigned to receive L-655,708 0.5 hour before or 23.5 hours after 1.3% isoflurane anesthesia.The Morris Water Maze tests demonstrated that L-655,708 injected before or after anesthesia could reverse the memory deficit in young rats. But in aged rats, application of L-655,708 only before anesthesia showed similar effects. Reverse transcription-polymerase chain reaction showed that low-dose isoflurane decreased the mRNA expression of α5 GABAARs in aging hippocampal neurons but increased that in young animals. These findings indicate that L-655,708 prevented but could not reverse 1.3% isoflurane-induced spatial learning and memory impairment in aged Wistar rats. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Academy of Military Medical Science of China(approval No. NBCDSER-IACUC-2015128) in December 2015.展开更多
The effect of Batroxobin on spatial memory disorder of left temporal ischemic rats and the expression of HSP32 and HSP70 were investigated with Morri`s water maze and immunohistochemistry methods. The results show... The effect of Batroxobin on spatial memory disorder of left temporal ischemic rats and the expression of HSP32 and HSP70 were investigated with Morri`s water maze and immunohistochemistry methods. The results showed that the mean reaction time and distance of temporal ischemic rats in searching a goal were significantly longer than those of the sham-operated rats and at the same time HSP32 and HSP70 expression of left temporal ischemic region in rats was significantly increased as compared with the sham-operated rats. However, the mean reaction time and distance of the Batroxobin-treated rats were shorter and they used normal strategies more often and earlier than those of ischemic rats. The number of HSP32 and HSP70 immune reactive cells of Batroxobin-treated rats was also less than that of the ischemic group. In conclusion, Batroxobin can improve spatial memory disorder of temporal ischemic rats; and the down-regulation of the expression of HSP32 and HSP70 is probably related to the attenuation of ischemic injury.展开更多
Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memor...Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.展开更多
Haze-fog,which is an atmospheric aerosol caused by natural or man-made factors,seriously affects the physical and mental health of human beings.PM2.5(a particulate matter whose diameter is smaller than or equal to 2.5...Haze-fog,which is an atmospheric aerosol caused by natural or man-made factors,seriously affects the physical and mental health of human beings.PM2.5(a particulate matter whose diameter is smaller than or equal to 2.5 microns)is the chief culprit causing aerosol.To forecast the condition of PM2.5,this paper adopts the related the meteorological data and air pollutes data to predict the concentration of PM2.5.Since the meteorological data and air pollutes data are typical time series data,it is reasonable to adopt a machine learning method called Single Hidden-Layer Long Short-Term Memory Neural Network(SSHL-LSTMNN)containing memory capability to implement the prediction.However,the number of neurons in the hidden layer is difficult to decide unless manual testing is operated.In order to decide the best structure of the neural network and improve the accuracy of prediction,this paper employs a self-organizing algorithm,which uses Information Processing Capability(IPC)to adjust the number of the hidden neurons automatically during a learning phase.In a word,to predict PM2.5 concentration accurately,this paper proposes the SSHL-LSTMNN to predict PM2.5 concentration.In the experiment,not only the hourly precise prediction but also the daily longer-term prediction is taken into account.At last,the experimental results reflect that SSHL-LSTMNN performs the best.展开更多
The objective of this paper is to model the size-dependent thermo-mechanical behaviors of a shape memory polymer (SMP) microbeam.Size-dependent constitutive equations,which can capture the size effect of the SMP,are p...The objective of this paper is to model the size-dependent thermo-mechanical behaviors of a shape memory polymer (SMP) microbeam.Size-dependent constitutive equations,which can capture the size effect of the SMP,are proposed based on the modified couple stress theory (MCST).The deformation energy expression of the SMP microbeam is obtained by employing the proposed size-dependent constitutive equation and Bernoulli-Euler beam theory.An SMP microbeam model,which includes the formulations of deflection,strain,curvature,stress and couple stress,is developed by using the principle of minimum potential energy and the separation of variables together.The sizedependent thermo-mechanical and shape memory behaviors of the SMP microbeam and the influence of the Poisson ratio are numerically investigated according to the developed SMP microbeam model.Results show that the size effects of the SMP microbeam are significant when the dimensionless height is small enough.However,they are too slight to be necessarily considered when the dimensionless height is large enough.The bending flexibility and stress level of the SMP microbeam rise with the increasing dimensionless height,while the couple stress level declines with the increasing dimensionless height.The larger the dimensionless height is,the more obvious the viscous property and shape memory effect of the SMP microbeam are.The Poisson ratio has obvious influence on the size-dependent behaviors of the SMP microbeam.The paper provides a theoretical basis and a quantitatively analyzing tool for the design and analysis of SMP micro-structures in the field of biological medicine,microelectronic devices and micro-electro-mechanical system (MEMS) self-assembling.展开更多
Mild intrauterine hypoperfusion(MIUH)is a serious pathological event that affects the growth and development of fetuses and offspring.MIUH can lead to growth restriction,low birth weight,neurodevelopmental disorders,a...Mild intrauterine hypoperfusion(MIUH)is a serious pathological event that affects the growth and development of fetuses and offspring.MIUH can lead to growth restriction,low birth weight,neurodevelopmental disorders,and other adverse clinical outcomes.To study the effects of MIUH on learning and memory function in offspring,a model of MIUH was established by placing a coil(length 2.5 mm,diameter 0.24 mm)on the uterine artery and ovarian uterine artery of Sprague-Dawley rats in the second trimester of pregnancy(day 17).Next,120 mg/kg lithium chloride(the MIUH+Li group)or normal saline(the MIUH group)was injected intraperitoneally into these rats.In addition,120 mg/kg lithium chloride(the Li group)or normal saline(the SHAM group)was injected intraperitoneally into pregnant rats without coil placement.The Morris water maze was used to detect changes in learning and memory ability in the offspring at 4 weeks after birth.In the MIUH group,the escape latency and journey length before reaching the platform were both increased,and the number of times that the platform was crossed and the activity time in the target quadrant within 90 seconds were both decreased compared with the SHAM group.Immunofluorescence double staining and western blot assays demonstrated that hippocampal nestin and Ki67(both cell-proliferation-related proteins)expression was significantly downregulated in the MIUH group compared with the SHAM group.Furthermore,western blot assays were conducted to investigate changes in related signaling pathway proteins in the brains of offspring rats,and revealed that glycogen synthase kinase 3β(GSK3β)expression was upregulated andβ-catenin expression was downregulated in the MIUH group compared with the SHAM group.In addition,compared with the MIUH group,the expression levels of p-GSK3βandβ-catenin were upregulated in the MIUH+Li group.These results suggest that MIUH may affect learning and memory function in rat offspring by regulating the GSK3βsignaling pathway.The experimental procedures were approved by Animal Ethics Committee of Shengjing Hospital of China Medical University(approval No.2018 PS07 K)in June 2018.展开更多
The tooth belongs to the trigeminal sensory pathway. Dental damage has been associated with impairments in the central nervous system that may be mediated by injury to the trigeminal nerve. In the present study, we in...The tooth belongs to the trigeminal sensory pathway. Dental damage has been associated with impairments in the central nervous system that may be mediated by injury to the trigeminal nerve. In the present study, we investigated the effects of damage to the inferior alveolar nerve, an important peripheral nerve in the trigeminal sensory pathway, on learning and memory be-haviors and structural changes in related brain regions, in a mouse model of Alzheimer’s disease. Inferior alveolar nerve transection or sham surgery was performed in middle-aged （4-month-old） or elderly （7-month-old） senescence-accelerated mouse prone 8 （SAMP8） mice. When the middle-aged mice reached 8 months （middle-aged group 1） or 11 months （middle-aged group 2）, and the elderly group reached 11 months, step-down passive avoidance and Y-maze tests of learn-ing and memory were performed, and the cholinergic system was examined in the hippocampus （Nissl staining and acetylcholinesterase histochemistry） and basal forebrain （choline acetyltrans-ferase immunohistochemistry）. In the elderly group, animals that underwent nerve transection had fewer pyramidal neurons in the hippocampal CA1 and CA3 regions, fewer cholinergic ifbers in the CA1 and dentate gyrus, and fewer cholinergic neurons in the medial septal nucleus and vertical limb of the diagonal band, compared with sham-operated animals, as well as showing impairments in learning and memory. Conversely, no signiifcant differences in histology or be-havior were observed between middle-aged group 1 or group 2 transected mice and age-matched sham-operated mice. The present ifndings suggest that trigeminal nerve damage in old age, but not middle age, can induce degeneration of the septal-hippocampal cholinergic system and loss of hippocampal pyramidal neurons, and ultimately impair learning ability. Our results highlight the importance of active treatment of trigeminal nerve damage in elderly patients and those with Alzheimer’s disease, and indicate that tooth extraction should be avoided in these populations.展开更多
As a typical in-memory computing hardware design, nonvolatile ternary content-addressable memories(TCAMs) enable the logic operation and data storage for high throughout in parallel big data processing. However,TCAM c...As a typical in-memory computing hardware design, nonvolatile ternary content-addressable memories(TCAMs) enable the logic operation and data storage for high throughout in parallel big data processing. However,TCAM cells based on conventional silicon-based devices suffer from structural complexity and large footprintlimitations. Here, we demonstrate an ultrafast nonvolatile TCAM cell based on the MoTe2/hBN/multilayergraphene (MLG) van der Waals heterostructure using a top-gated partial floating-gate field-effect transistor(PFGFET) architecture. Based on its ambipolar transport properties, the carrier type in the source/drain andcentral channel regions of the MoTe2 channel can be efficiently tuned by the control gate and top gate, respectively,enabling the reconfigurable operation of the device in either memory or FET mode. When working inthe memory mode, it achieves an ultrafast 60 ns programming/erase speed with a current on-off ratio of ∼105,excellent retention capability, and robust endurance. When serving as a reconfigurable transistor, unipolar p-typeand n-type FETs are obtained by adopting ultrafast 60 ns control-gate voltage pulses with different polarities.The monolithic integration of memory and logic within a single device enables the content-addressable memory(CAM) functionality. Finally, by integrating two PFGFETs in parallel, a TCAM cell with a high current ratioof ∼10^(5) between the match and mismatch states is achieved without requiring additional peripheral circuitry.These results provide a promising route for the design of high-performance TCAM devices for future in-memorycomputing applications.展开更多
This study investigates the application of Learnable Memory Vision Transformers(LMViT)for detecting metal surface flaws,comparing their performance with traditional CNNs,specifically ResNet18 and ResNet50,as well as o...This study investigates the application of Learnable Memory Vision Transformers(LMViT)for detecting metal surface flaws,comparing their performance with traditional CNNs,specifically ResNet18 and ResNet50,as well as other transformer-based models including Token to Token ViT,ViT withoutmemory,and Parallel ViT.Leveraging awidely-used steel surface defect dataset,the research applies data augmentation and t-distributed stochastic neighbor embedding(t-SNE)to enhance feature extraction and understanding.These techniques mitigated overfitting,stabilized training,and improved generalization capabilities.The LMViT model achieved a test accuracy of 97.22%,significantly outperforming ResNet18(88.89%)and ResNet50(88.90%),aswell as the Token to TokenViT(88.46%),ViT without memory(87.18),and Parallel ViT(91.03%).Furthermore,LMViT exhibited superior training and validation performance,attaining a validation accuracy of 98.2%compared to 91.0%for ResNet 18,96.0%for ResNet50,and 89.12%,87.51%,and 91.21%for Token to Token ViT,ViT without memory,and Parallel ViT,respectively.The findings highlight the LMViT’s ability to capture long-range dependencies in images,an areawhere CNNs struggle due to their reliance on local receptive fields and hierarchical feature extraction.The additional transformer-based models also demonstrate improved performance in capturing complex features over CNNs,with LMViT excelling particularly at detecting subtle and complex defects,which is critical for maintaining product quality and operational efficiency in industrial applications.For instance,the LMViT model successfully identified fine scratches and minor surface irregularities that CNNs often misclassify.This study not only demonstrates LMViT’s potential for real-world defect detection but also underscores the promise of other transformer-based architectures like Token to Token ViT,ViT without memory,and Parallel ViT in industrial scenarios where complex spatial relationships are key.Future research may focus on enhancing LMViT’s computational efficiency for deployment in real-time quality control systems.展开更多
Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering technique.The influence of sintering parameters on porosity reduction,microstructure,phase transformatio...Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering technique.The influence of sintering parameters on porosity reduction,microstructure,phase transformation temperatures,and mechanical properties were investigated by optical microscopy,field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD),differential scanning calorimetry(DSC),compression tests,and microhardness tests.Varying the microwave temperature and holding time was found to strongly affect the density of porosity,presence of precipitates,transformation temperatures,and mechanical properties.The lowest density and smallest pore size were observed in the Ti–51at%Ni samples sintered at 900°C for 5 min or at 900°C for 30 min.The predominant martensite phases of β2 and β19′ were observed in the microstructure of Ti–51at%Ni,and their existence varied in accordance with the sintering temperature and the holding time.In the DSC thermograms,multi-transformation peaks were observed during heating,whereas a single peak was observed during cooling;these peaks correspond to the presence of the β2,R,and β19′ phases.The maximum strength and strain among the Ti–51at%Ni SMAs were 1376 MPa and 29%,respectively,for the sample sintered at 900°C for 30 min because of this sample's minimal porosity.展开更多
The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and e...The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and existence of uniform attractor under some suitable assumptions on the nonlinear term g(u),the nonlinear damping f(u_(t))and the external force h(x,t).Specifically,the asymptotic compactness of the semigroup is verified by the energy reconstruction method.展开更多
Isoflurane and sevoflurane are both inhalation anesthetics,but in clinical application,sevoflurane has been considered to be less suitable for long-term anesthesia because of its catabolic compounds and potential neph...Isoflurane and sevoflurane are both inhalation anesthetics,but in clinical application,sevoflurane has been considered to be less suitable for long-term anesthesia because of its catabolic compounds and potential nephrotoxicity.Nevertheless,recent studies have shown that these two inhalation anesthetics are similar in hepatorenal toxicity,cost,and long-term anesthetic effect.Moreover,sevoflurane possibly has less cognitive impact on young mice.In this study,C57BL/6 mice aged 8–10 weeks were exposed to 1.2%isoflurane or 2.4%sevoflurane for 6 hours.Cognitive function and memory were examined in young mice using the novel object recognition,contextual fear conditioning,and cued-fear extinction tests.Western blot assay was performed to detect expression levels of D1 dopamine receptor,catechol-O-methyltransferase,phospho-glycogen synthase kinase-3β,and total glycogen synthase kinase-3βin the hippocampus.Our results show that impaired performance was not detected in mice exposed to sevoflurane during the novel object recognition test.Contextual memory impairment in the fear conditioning test was shorter in the sevoflurane group than the isoflurane group.Long-term sevoflurane exposure did not affect memory consolidation,while isoflurane led to memory consolidation and reduced retention.Downregulation of hippocampal D1 dopamine receptors and phosphorylated glycogen synthase kinase-3β/total glycogen synthase kinase-3βand upregulation of catechol-O-methyltransferase may be associated with differing memory performance after exposure to isoflurane or sevoflurane.These results confirm that sevoflurane has less effect on cognitive impairment than isoflurane,which may be related to expression of D1 dopamine receptors and catechol-O-methyltransferase and phosphorylation of glycogen synthase kinase-3βin the hippocampus.This study was approved by the Institutional Animal Care and Use Committee,Nanjing University,China on November 20,2017(approval No.20171102).展开更多
Eleutheroside B or E, the main component of Acanthopanax, can relieve fatigue, enhance memory, and improve human cognition. Numerous studies have confirmed that high doses of acetylcholine significantly attenuate clin...Eleutheroside B or E, the main component of Acanthopanax, can relieve fatigue, enhance memory, and improve human cognition. Numerous studies have confirmed that high doses of acetylcholine significantly attenuate clinical symptoms and delay the progression of Alzheimer＇s disease. The present study replicated a rat model of aging induced by injecting quinolinic acid into the hippocampal CA1 region. These rats were intraperitoneally injected with low, medium and high doses of eleutheroside B or E （50, 100, 200 mg/kg）, and rats injected with Huperzine A or PBS were used as controls. At 4 weeks after administration, behavioral tests showed that the escape latencies and errors in searching for the platform in a Morris water maze were dose-dependently reduced in rats treated with medium and high-dose eleutheroside B or E. Hematoxylin-eosin staining showed that the number of surviving hippocampal neurons was greater and pathological injury was milder in three eleutheroside B or E groups compared with model group. Hippocampal homogenates showed enhanced cholinesterase activity, and dose-dependent increases in acetylcholine content and decreases in choline content following eleutheroside B or E treatment, similar to those seen in the Huperzine A group. These findings indicate that eleutheroside B or E improves learning and memory in aged rats. These effects of eleutheroside B or E may be mediated by activation of cholinesterase or enhanced reuse of choline to accelerate the synthesis of acetylcholine in hippocampal neurons.展开更多
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 ...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.展开更多
N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis a...N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be attributed to the timespecific nature of m^(6)A and its varying effects on distinct brain regions and in different environments.展开更多
文摘Transthyretin (TTR), a carrier protein present in the liver and choroid plexus of the brain, has been shown to be responsible for binding thyroid hormone thyroxin (T4) and retinol in plasma and cerebrospinal fluid (CSF). TTR aids in sequestering of beta-amyloid peptides Aβ deposition, and protects the brain from trauma, ischemic stroke and Alzheimer disease (AD). Accordingly, hippocampal gene expression of TTR plays a significant role in learning and memory as well as in simulation of spatial memory tasks. TTR via interacting with transcription factor CREB regulates this process and decreased expression leads to memory deficits. By different signaling pathways, like MAPK, AKT, and ERK via Src, TTR provides tropical support through megalin receptor by promoting neurite outgrowth and protecting the neurons from traumatic brain injury. TTR is also responsible for the transient rise in intracellular Ca2+ via NMDA receptor, playing a dominant role under excitotoxic conditions. In this review, we tried to shed light on how TTR is involved in maintaining normal cognitive processes, its role in learning and memory, under memory deficit conditions;by which mechanisms it promotes neurite outgrowth;and how it protects the brain from Alzheimer disease (AD).
基金supported by the National Natural Science Foundation of China,No.81171191(to LYZ)the Shenzhen Special Fund Project on Strategic Emerging Industry Development of China,No.JCYJ20160422170522075(to LYZ)the Shenzhen Healthcare Research Project of China,No.201601015(to LYZ)
文摘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.
文摘There are presently no in-depth published neuropsychological studies of West Nile Virus (WNV) encephalitis patients that have been well-correlated with high resolution structural MRI. In this study a middleaged male who developed West Nile Virus encephalitis five years previously was examined three times over a two year period. We examined him with the Wechsler Adult Intelligence Scales—Fourth Edition and the Wechsler Memory Scale—Fourth Edition (WAIS-IV/WMS-IV) and Advanced Clinical Solutions battery supplemented by tests of attention, executive, motor and sensory functions. Neuroradiological imaging revealed hypodensities within the left hippocampus in the axial and coronal planes with T2-FLAIR MRI. The man was previously high functioning and although he had prior history of well-controlled epilepsy it seems unlikely that the epilepsy could fully account for the neuropathological changes. The patient had previously completed a demanding six year double science degree program before he became ill with WNV and he had been a successful manager and director of a research company. Delayed auditory memory scores were at least two standard deviation units below age expected levels and semantic fluency and Booklet Category Tests of executive function were also in the impaired range. Moreover the illness onset profile of muscle weakness, extreme fatigue, memory complaints as well as inability to carry out research projects involving planning on the job were highly consistent with WNV encephalitis. If the memory and executive function deficits had been premorbid manifestations of epilepsy it is unlikely he would have attained the levels he did educationally and occupationally. This left hippocampal lesion is characteristic of other encephalitic viral infections such as herpes simplex virus. To our knowledge this is the first lateralized WNV encephalitis medial temporal lobe patient in the published literature.
基金financially supported by the National Innovation and Entrepreneurship Training Project of China in 2013,No.201310392009(to XZZ)the Innovation and Entrepreneurship Training Project of Fujian Province of China in 2014,No.201410392058(to XZZ)
文摘Oxidative stress is involved in the pathogenesis of vascular dementia. Studies have shown that lycopene can significantly inhibit oxidative stress;therefore, we hypothesized that lycopene can reduce the level of oxidative stress in vascular dementia. A vascular dementia model was established by permanent bilateral ligation of common carotid arteries. The dosage groups were treated with lycopene(50, 100 and 200 mg/kg) every other day for 2 months. Rats without bilateral carotid artery ligation were prepared as a sham group. To test the ability of learning and memory, the Morris water maze was used to detect the average escape latency and the change of search strategy. Hematoxylin-eosin staining was used to observe changes of hippocampal neurons. The levels of oxidative stress factors, superoxide dismutase and malondialdehyde, were measured in the hippocampus by biochemical detection. The levels of reactive oxygen species in the hippocampus were observed by dihydroethidium staining. The distribution and expression of oxidative stress related protein, neuron-restrictive silencer factor, in hippocampal neurons were detected by immunofluorescence histochemistry and western blot assays. After 2 months of drug administration,(1) in the model group, the average escape latency was longer than that of the sham group, and the proportion of straight and tend tactics was lower than that of the sham group, and the hippocampal neurons were irregularly arranged and the cytoplasm was hyperchromatic.(2) The levels of reactive oxygen species and malondialdehyde in the hippocampus of the model group rats were increased, and the activity of superoxide dismutase was decreased.(3) Lycopene(50, 100 and 200 mg/kg) intervention improved the above changes, and the lycopene 100 mg/kg group showed the most significant improvement effect.(4) Neuron-restrictive silencer factor expression in the hippocampus was lower in the sham group and the lycopene 100 mg/kg group than in the model group.(5) The above data indicate that lycopene 100 mg/kg could protect against the learning-memory ability impairment of vascular dementia rats. The protective mechanism was achieved by inhibiting oxidative stress in the hippocampus. The experiment was approved by the Animal Ethics Committee of Fujian Medical University, China(approval No. 2014-025) in June 2014.
文摘The α5 subunit-containing gamma-amino butyric acid type A receptors(α5 GABAARs) are a distinct subpopulation that are specifically distributed in the mammalian hippocampus and also mediate tonic inhibitory currents in hippocampal neurons. These tonic currents can be enhanced by low-dose isoflurane, which is associated with learning and memory impairment. Inverse agonists of α5 GABAARs, such as L-655,708, are able to reverse the short-term memory deficit caused by low-dose isoflurane in young animals. However, whether these negative allosteric modulators have the same effects on aged rats remains unclear. In the present study, we mainly investigated the effects of L-655,708 on low-dose(1.3%) isoflurane-induced learning and memory impairment in elderly rats. Young(3-month-old) and aged(24-month-old) Wistar rats were randomly assigned to receive L-655,708 0.5 hour before or 23.5 hours after 1.3% isoflurane anesthesia.The Morris Water Maze tests demonstrated that L-655,708 injected before or after anesthesia could reverse the memory deficit in young rats. But in aged rats, application of L-655,708 only before anesthesia showed similar effects. Reverse transcription-polymerase chain reaction showed that low-dose isoflurane decreased the mRNA expression of α5 GABAARs in aging hippocampal neurons but increased that in young animals. These findings indicate that L-655,708 prevented but could not reverse 1.3% isoflurane-induced spatial learning and memory impairment in aged Wistar rats. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Academy of Military Medical Science of China(approval No. NBCDSER-IACUC-2015128) in December 2015.
文摘 The effect of Batroxobin on spatial memory disorder of left temporal ischemic rats and the expression of HSP32 and HSP70 were investigated with Morri`s water maze and immunohistochemistry methods. The results showed that the mean reaction time and distance of temporal ischemic rats in searching a goal were significantly longer than those of the sham-operated rats and at the same time HSP32 and HSP70 expression of left temporal ischemic region in rats was significantly increased as compared with the sham-operated rats. However, the mean reaction time and distance of the Batroxobin-treated rats were shorter and they used normal strategies more often and earlier than those of ischemic rats. The number of HSP32 and HSP70 immune reactive cells of Batroxobin-treated rats was also less than that of the ischemic group. In conclusion, Batroxobin can improve spatial memory disorder of temporal ischemic rats; and the down-regulation of the expression of HSP32 and HSP70 is probably related to the attenuation of ischemic injury.
基金supported by grants from the National Natural Science Foundation of China, No. 30872132
文摘Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.
文摘Haze-fog,which is an atmospheric aerosol caused by natural or man-made factors,seriously affects the physical and mental health of human beings.PM2.5(a particulate matter whose diameter is smaller than or equal to 2.5 microns)is the chief culprit causing aerosol.To forecast the condition of PM2.5,this paper adopts the related the meteorological data and air pollutes data to predict the concentration of PM2.5.Since the meteorological data and air pollutes data are typical time series data,it is reasonable to adopt a machine learning method called Single Hidden-Layer Long Short-Term Memory Neural Network(SSHL-LSTMNN)containing memory capability to implement the prediction.However,the number of neurons in the hidden layer is difficult to decide unless manual testing is operated.In order to decide the best structure of the neural network and improve the accuracy of prediction,this paper employs a self-organizing algorithm,which uses Information Processing Capability(IPC)to adjust the number of the hidden neurons automatically during a learning phase.In a word,to predict PM2.5 concentration accurately,this paper proposes the SSHL-LSTMNN to predict PM2.5 concentration.In the experiment,not only the hourly precise prediction but also the daily longer-term prediction is taken into account.At last,the experimental results reflect that SSHL-LSTMNN performs the best.
基金Project supported by the National Key Research and Development Program of China(No.2017YFC0307604)the Talent Foundation of China University of Petroleum(No.Y1215042)the Graduate Innovation Program of China University of Petroleum(East China)(No.YCX2019084)
文摘The objective of this paper is to model the size-dependent thermo-mechanical behaviors of a shape memory polymer (SMP) microbeam.Size-dependent constitutive equations,which can capture the size effect of the SMP,are proposed based on the modified couple stress theory (MCST).The deformation energy expression of the SMP microbeam is obtained by employing the proposed size-dependent constitutive equation and Bernoulli-Euler beam theory.An SMP microbeam model,which includes the formulations of deflection,strain,curvature,stress and couple stress,is developed by using the principle of minimum potential energy and the separation of variables together.The sizedependent thermo-mechanical and shape memory behaviors of the SMP microbeam and the influence of the Poisson ratio are numerically investigated according to the developed SMP microbeam model.Results show that the size effects of the SMP microbeam are significant when the dimensionless height is small enough.However,they are too slight to be necessarily considered when the dimensionless height is large enough.The bending flexibility and stress level of the SMP microbeam rise with the increasing dimensionless height,while the couple stress level declines with the increasing dimensionless height.The larger the dimensionless height is,the more obvious the viscous property and shape memory effect of the SMP microbeam are.The Poisson ratio has obvious influence on the size-dependent behaviors of the SMP microbeam.The paper provides a theoretical basis and a quantitatively analyzing tool for the design and analysis of SMP micro-structures in the field of biological medicine,microelectronic devices and micro-electro-mechanical system (MEMS) self-assembling.
基金supported by the National Key Research&Department Program of China,No.2018YFC1002902(to CXL)。
文摘Mild intrauterine hypoperfusion(MIUH)is a serious pathological event that affects the growth and development of fetuses and offspring.MIUH can lead to growth restriction,low birth weight,neurodevelopmental disorders,and other adverse clinical outcomes.To study the effects of MIUH on learning and memory function in offspring,a model of MIUH was established by placing a coil(length 2.5 mm,diameter 0.24 mm)on the uterine artery and ovarian uterine artery of Sprague-Dawley rats in the second trimester of pregnancy(day 17).Next,120 mg/kg lithium chloride(the MIUH+Li group)or normal saline(the MIUH group)was injected intraperitoneally into these rats.In addition,120 mg/kg lithium chloride(the Li group)or normal saline(the SHAM group)was injected intraperitoneally into pregnant rats without coil placement.The Morris water maze was used to detect changes in learning and memory ability in the offspring at 4 weeks after birth.In the MIUH group,the escape latency and journey length before reaching the platform were both increased,and the number of times that the platform was crossed and the activity time in the target quadrant within 90 seconds were both decreased compared with the SHAM group.Immunofluorescence double staining and western blot assays demonstrated that hippocampal nestin and Ki67(both cell-proliferation-related proteins)expression was significantly downregulated in the MIUH group compared with the SHAM group.Furthermore,western blot assays were conducted to investigate changes in related signaling pathway proteins in the brains of offspring rats,and revealed that glycogen synthase kinase 3β(GSK3β)expression was upregulated andβ-catenin expression was downregulated in the MIUH group compared with the SHAM group.In addition,compared with the MIUH group,the expression levels of p-GSK3βandβ-catenin were upregulated in the MIUH+Li group.These results suggest that MIUH may affect learning and memory function in rat offspring by regulating the GSK3βsignaling pathway.The experimental procedures were approved by Animal Ethics Committee of Shengjing Hospital of China Medical University(approval No.2018 PS07 K)in June 2018.
基金supported by the National Natural Science Foundation of China,No.81371107,81470760the Natural Science Foundation of Guangdong Province in China,No.S2013010015888+1 种基金the Foundation of Open Laboratory of Sun Yat-sen University in China,No.KF201312a grant from Translational Medicine Center,Guangdong Department of Science&Technology,No.2011A080300002
文摘The tooth belongs to the trigeminal sensory pathway. Dental damage has been associated with impairments in the central nervous system that may be mediated by injury to the trigeminal nerve. In the present study, we investigated the effects of damage to the inferior alveolar nerve, an important peripheral nerve in the trigeminal sensory pathway, on learning and memory be-haviors and structural changes in related brain regions, in a mouse model of Alzheimer’s disease. Inferior alveolar nerve transection or sham surgery was performed in middle-aged （4-month-old） or elderly （7-month-old） senescence-accelerated mouse prone 8 （SAMP8） mice. When the middle-aged mice reached 8 months （middle-aged group 1） or 11 months （middle-aged group 2）, and the elderly group reached 11 months, step-down passive avoidance and Y-maze tests of learn-ing and memory were performed, and the cholinergic system was examined in the hippocampus （Nissl staining and acetylcholinesterase histochemistry） and basal forebrain （choline acetyltrans-ferase immunohistochemistry）. In the elderly group, animals that underwent nerve transection had fewer pyramidal neurons in the hippocampal CA1 and CA3 regions, fewer cholinergic ifbers in the CA1 and dentate gyrus, and fewer cholinergic neurons in the medial septal nucleus and vertical limb of the diagonal band, compared with sham-operated animals, as well as showing impairments in learning and memory. Conversely, no signiifcant differences in histology or be-havior were observed between middle-aged group 1 or group 2 transected mice and age-matched sham-operated mice. The present ifndings suggest that trigeminal nerve damage in old age, but not middle age, can induce degeneration of the septal-hippocampal cholinergic system and loss of hippocampal pyramidal neurons, and ultimately impair learning ability. Our results highlight the importance of active treatment of trigeminal nerve damage in elderly patients and those with Alzheimer’s disease, and indicate that tooth extraction should be avoided in these populations.
基金supported by the National Key Research&Development Projects of China(Grant No.2022YFA1204100)National Natural Science Foundation of China(Grant No.62488201)+1 种基金CAS Project for Young Scientists in Basic Research(YSBR-003)the Innovation Program of Quantum Science and Technology(2021ZD0302700)。
文摘As a typical in-memory computing hardware design, nonvolatile ternary content-addressable memories(TCAMs) enable the logic operation and data storage for high throughout in parallel big data processing. However,TCAM cells based on conventional silicon-based devices suffer from structural complexity and large footprintlimitations. Here, we demonstrate an ultrafast nonvolatile TCAM cell based on the MoTe2/hBN/multilayergraphene (MLG) van der Waals heterostructure using a top-gated partial floating-gate field-effect transistor(PFGFET) architecture. Based on its ambipolar transport properties, the carrier type in the source/drain andcentral channel regions of the MoTe2 channel can be efficiently tuned by the control gate and top gate, respectively,enabling the reconfigurable operation of the device in either memory or FET mode. When working inthe memory mode, it achieves an ultrafast 60 ns programming/erase speed with a current on-off ratio of ∼105,excellent retention capability, and robust endurance. When serving as a reconfigurable transistor, unipolar p-typeand n-type FETs are obtained by adopting ultrafast 60 ns control-gate voltage pulses with different polarities.The monolithic integration of memory and logic within a single device enables the content-addressable memory(CAM) functionality. Finally, by integrating two PFGFETs in parallel, a TCAM cell with a high current ratioof ∼10^(5) between the match and mismatch states is achieved without requiring additional peripheral circuitry.These results provide a promising route for the design of high-performance TCAM devices for future in-memorycomputing applications.
基金funded by Woosong University Academic Research 2024.
文摘This study investigates the application of Learnable Memory Vision Transformers(LMViT)for detecting metal surface flaws,comparing their performance with traditional CNNs,specifically ResNet18 and ResNet50,as well as other transformer-based models including Token to Token ViT,ViT withoutmemory,and Parallel ViT.Leveraging awidely-used steel surface defect dataset,the research applies data augmentation and t-distributed stochastic neighbor embedding(t-SNE)to enhance feature extraction and understanding.These techniques mitigated overfitting,stabilized training,and improved generalization capabilities.The LMViT model achieved a test accuracy of 97.22%,significantly outperforming ResNet18(88.89%)and ResNet50(88.90%),aswell as the Token to TokenViT(88.46%),ViT without memory(87.18),and Parallel ViT(91.03%).Furthermore,LMViT exhibited superior training and validation performance,attaining a validation accuracy of 98.2%compared to 91.0%for ResNet 18,96.0%for ResNet50,and 89.12%,87.51%,and 91.21%for Token to Token ViT,ViT without memory,and Parallel ViT,respectively.The findings highlight the LMViT’s ability to capture long-range dependencies in images,an areawhere CNNs struggle due to their reliance on local receptive fields and hierarchical feature extraction.The additional transformer-based models also demonstrate improved performance in capturing complex features over CNNs,with LMViT excelling particularly at detecting subtle and complex defects,which is critical for maintaining product quality and operational efficiency in industrial applications.For instance,the LMViT model successfully identified fine scratches and minor surface irregularities that CNNs often misclassify.This study not only demonstrates LMViT’s potential for real-world defect detection but also underscores the promise of other transformer-based architectures like Token to Token ViT,ViT without memory,and Parallel ViT in industrial scenarios where complex spatial relationships are key.Future research may focus on enhancing LMViT’s computational efficiency for deployment in real-time quality control systems.
基金financial support under the University Research Grant No.Q.J130000.3024.00M57
文摘Ti–51at%Ni shape memory alloys(SMAs) were successfully produced via a powder metallurgy and microwave sintering technique.The influence of sintering parameters on porosity reduction,microstructure,phase transformation temperatures,and mechanical properties were investigated by optical microscopy,field-emission scanning electron microscopy(FE-SEM),X-ray diffraction(XRD),differential scanning calorimetry(DSC),compression tests,and microhardness tests.Varying the microwave temperature and holding time was found to strongly affect the density of porosity,presence of precipitates,transformation temperatures,and mechanical properties.The lowest density and smallest pore size were observed in the Ti–51at%Ni samples sintered at 900°C for 5 min or at 900°C for 30 min.The predominant martensite phases of β2 and β19′ were observed in the microstructure of Ti–51at%Ni,and their existence varied in accordance with the sintering temperature and the holding time.In the DSC thermograms,multi-transformation peaks were observed during heating,whereas a single peak was observed during cooling;these peaks correspond to the presence of the β2,R,and β19′ phases.The maximum strength and strain among the Ti–51at%Ni SMAs were 1376 MPa and 29%,respectively,for the sample sintered at 900°C for 30 min because of this sample's minimal porosity.
基金Supported by the National Natural Science Foundation of China(Grant Nos.11961059,1210502)the University Innovation Project of Gansu Province(Grant No.2023B-062)the Gansu Province Basic Research Innovation Group Project(Grant No.23JRRA684).
文摘The goal of this paper is to investigate the long-time dynamics of solutions to a Kirchhoff type suspension bridge equation with nonlinear damping and memory term.For this problem we establish the well-posedness and existence of uniform attractor under some suitable assumptions on the nonlinear term g(u),the nonlinear damping f(u_(t))and the external force h(x,t).Specifically,the asymptotic compactness of the semigroup is verified by the energy reconstruction method.
基金supported by the National Natural Science Foundation of China,No.81730033(to XPG),No.81701371(to TJX)
文摘Isoflurane and sevoflurane are both inhalation anesthetics,but in clinical application,sevoflurane has been considered to be less suitable for long-term anesthesia because of its catabolic compounds and potential nephrotoxicity.Nevertheless,recent studies have shown that these two inhalation anesthetics are similar in hepatorenal toxicity,cost,and long-term anesthetic effect.Moreover,sevoflurane possibly has less cognitive impact on young mice.In this study,C57BL/6 mice aged 8–10 weeks were exposed to 1.2%isoflurane or 2.4%sevoflurane for 6 hours.Cognitive function and memory were examined in young mice using the novel object recognition,contextual fear conditioning,and cued-fear extinction tests.Western blot assay was performed to detect expression levels of D1 dopamine receptor,catechol-O-methyltransferase,phospho-glycogen synthase kinase-3β,and total glycogen synthase kinase-3βin the hippocampus.Our results show that impaired performance was not detected in mice exposed to sevoflurane during the novel object recognition test.Contextual memory impairment in the fear conditioning test was shorter in the sevoflurane group than the isoflurane group.Long-term sevoflurane exposure did not affect memory consolidation,while isoflurane led to memory consolidation and reduced retention.Downregulation of hippocampal D1 dopamine receptors and phosphorylated glycogen synthase kinase-3β/total glycogen synthase kinase-3βand upregulation of catechol-O-methyltransferase may be associated with differing memory performance after exposure to isoflurane or sevoflurane.These results confirm that sevoflurane has less effect on cognitive impairment than isoflurane,which may be related to expression of D1 dopamine receptors and catechol-O-methyltransferase and phosphorylation of glycogen synthase kinase-3βin the hippocampus.This study was approved by the Institutional Animal Care and Use Committee,Nanjing University,China on November 20,2017(approval No.20171102).
基金supported by the Foundation from Department of Education of Hubei Province,No.D20111903
文摘Eleutheroside B or E, the main component of Acanthopanax, can relieve fatigue, enhance memory, and improve human cognition. Numerous studies have confirmed that high doses of acetylcholine significantly attenuate clinical symptoms and delay the progression of Alzheimer＇s disease. The present study replicated a rat model of aging induced by injecting quinolinic acid into the hippocampal CA1 region. These rats were intraperitoneally injected with low, medium and high doses of eleutheroside B or E （50, 100, 200 mg/kg）, and rats injected with Huperzine A or PBS were used as controls. At 4 weeks after administration, behavioral tests showed that the escape latencies and errors in searching for the platform in a Morris water maze were dose-dependently reduced in rats treated with medium and high-dose eleutheroside B or E. Hematoxylin-eosin staining showed that the number of surviving hippocampal neurons was greater and pathological injury was milder in three eleutheroside B or E groups compared with model group. Hippocampal homogenates showed enhanced cholinesterase activity, and dose-dependent increases in acetylcholine content and decreases in choline content following eleutheroside B or E treatment, similar to those seen in the Huperzine A group. These findings indicate that eleutheroside B or E improves learning and memory in aged rats. These effects of eleutheroside B or E may be mediated by activation of cholinesterase or enhanced reuse of choline to accelerate the synthesis of acetylcholine in hippocampal neurons.
基金supported by grants from the Ministerio de Economia y Competitividad(BFU2013-43458-R)Junta de Andalucia(P12-CTS-1694 and Proyexcel-00422)to ZUK。
文摘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.
基金supported by the Natural Science Foundation of Heilongjiang Province of China,Outstanding Youth Foundation,No.YQ2022H003 (to DW)。
文摘N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be attributed to the timespecific nature of m^(6)A and its varying effects on distinct brain regions and in different environments.
